I'm a CNC machinist by trade. I program gcode for Haas CNC mills both manually by hand and using cam software to complement more complex features. We cut mostly 6061, and we HOG it. There are a few key things I've learned over the years: 1) RADIAL ENGAGEMENT (this is the #1 source for the difference between a good or bad cut) - the amount of the diameter of the cutter that is engaged with the material being cut. The more the material wraps around the cutter, the less time the cutter has to cool off between cuts, and less opportunity for chips to leave the cutting area. I like between 5-25% engagement depending on diameter of the cutter. Keep in mind that not all cutters are made the same, and the simple act of plunging can ruin some cutters no matter what you try (it's often better to ramp down at an angle or Helix into part instead of plunging in z-axis only) 2) chip evacuation - both in the cutter and on the workpiece. If the cutter begins to re-cut chips it already removed from the material, it will develop premature wear and/or chip a cutting edge or break. If there isn't proper room for the chip to exit the relief area of the cutter, the cutter will clog up and begin the welding process. 2.5) cutter geometry (WOW)... This one is somewhat really important. Aluminum LOVES non-coated high polish solid carbide end mills with a sharp edge and a margin after cutting edge (to prevent the cutter pulling itself into material off-axis of rotation) as well as a high Helix. We run between 30-45deg Helix normally, and the only exception is extra long tooling. we are currently running a job that uses a custom ground .125" dia by 5/8" length of cut end Mill that we will probably have to shorten up because of chatter 3) coolant - well not really. It helps tremendously when you are taking deep and fast cuts with large stepovers, but if you learn from bullet point (1) then you will realize coolant helps but is not a king pin requirement. Coolant allows you to cross that radial/heat buildup issue by transferring heat away. Keeping radial engagement in your mind when programming toolpaths will relegate coolant's job more to long term tool life rather than short term (we have had 1/2" end mills that ran for 2+ years @ 40hrs/WK at a material removal rate of 20+ cubic inches per minute; that's 200,000 cubic inches of material a month as waste material in chips if I did mental math right) 4) rigidity - you mentioned this in your video. Pretty much is a basic tenet of machining. Good clean cuts require rigid machines and tools (most of the time; some operations benefit from some slight flexing but that's another topic). I didn't mean this post to end up so long. I got carried away sharing my knowledge from my passion/profession... Lol Good luck to you, and I hope I helped future endeavors.
All fantastic information. No amount of internet research can replace experience. I'm actually a little curious now about what cases you think tool/machine deflection isn't a purely negative behavior...
when chasing an existing hole, using a rigid tool where the 2nd drill doesn't line up precisely leads to heavier engagement on one side of the tool. Using high speed steel tools (or flex in the machine frame) can allow the tool to flex without breaking. A solid carbide tool (especially a smaller tool size) in a rigid machine could break off in the hole because it is hard yet brittle and does not like flexing. This could swing the other way also, as too much movement could also allow the 2nd tool to bind in the hole. Deflection in carbide tools = breaking, chipping, edge wearing. Simply put, if carbide is engaged with work material and it's not cutting the material, then it's bad news bears. There are cases where a tap would benefit from less rigidity. Google "tapmatic" units (I think I got the spelling right). They have a special tool holding assembly that allows the tool to move off axis while still being straight (like the couplers that connect the stepper motors to the lead screws on other router tables) I can't think of any other situations at the moment. Typically rigidity is best
Comments from passionate professionals are often very good. Dense with information. Yours definitely is well appreciated by me, and I imagine anyone who is thinking about cutting aluminum or has started to and is having difficulty. Its one thing to think you have an idea what is going on, and another to have your suspicions confirmed by a pro.
Great video as usual Winston! I've been cutting quite a bit of Aluminum with my heavily modified Shapeoko 2; I've gone as thick as 3/8 and would feel comfortable going thicker. Also, I use a dust shoe and cut with no lubricant. I found that the lubricant just causes chips to not be picked up by the dust shoe. The thing I noticed in the video that I do differently relates to tabs. Say, on a job where I am making a bracket, which bolts to something, I break the gcode into two files. 1. The bracket bolt holes. 2. The bracket outer profile. Assuming you don't lose 0, 0, 0 (x, y, z) between jobs and there is a waste board below your aluminum, you eliminate the need for tabs. Step 1. Secure your aluminum sheet Step 2. Cut job 1 (the bolt holes) Step 3. Move your gantry clear of the bolt holes cut in Step 2 (retaining 0, 0, 0; but keeping the motors locked) Step 4. Use self-tapping screws to secure what will become the bracket, by putting a self-tapping screw into each of the bolt holes created in Step 2 Step 5. Cut job 2 (the outer profile) I can't stand the little imperfections created by tabs. Though, in the case where you don't have holes in the middle of the piece, you are forced to use tabs :/ Hope this is helpful!
For aluminum in the Linamar Plants in Canada we used Varsol in a spray bottle to cool the carbide cutters while cutting Aluminum Chevy V-6 water pumps. It work very well. I found that the way my Machine was setup the the first month of running it was to slow and could never get a mirror like finish that was needed for Quality Control so i dial indicated the 12 cutter in the cutting head which removed the vibration, it was a old manual machine. I picked the lowest cutter and shimmed all the rest to match it, then i double the feed and RPM's of the tool and that allowed me to double my hourly out put with a mirror like finish. this got me a raise and allowed me to do my own machine setups after that. That was 38 years ago. Try using conventional cutting when using the Shapeoko 3 because the light frame is like having backlash problems when using small flexible cutters Climb cutting pushes the cutting edge away from the stock and conventional draws the tool edge closer to the material which gives a more controlled size and needs less spring cuts do to tool flex.
If you will take smaller cuts you can greatly increase your feed rate. Try doing cuts at .025-.05 I know it seems like deeper cuts would be faster but it's not. You get the highest material removal rate with high feed rate /small DOC(depth of cut) This style is one of the major contributors to high speed machining. You can also save a lot of endmills by cutting your stock to smaller sizes and profile the part instead of the slot cut your doing. Slots and pockets are the hardest on your tools especially when you don't have coolant. Compressed air will serve you better than the oil you are using. Chip removal is more important than heat in this case.
On my CNC router ( my design and build), I also use the Dewalt router as shown in your video and I also run it at about 80% of it Max RPM. But, I use 1/8" single flute end mills that I buy from drillman on eBay, at 20 Inches per minute, and a .030" depth of cut. As you have found, a good blast of air to clear the chips is a must or they will weld to your cutter and break it. I do not use any coolant - just air. I have cut up to 1/2" aluminum this way without cutting a wider channel first for chip clearance.
A good starting point for speeds and feeds is : cutter speed ( you can look up the cutter speed value for any given material in the "Machineries Handbook" ) X 4 divided by diameter . Back off on the speeds and feeds for your first run, then increase to see how much the project / set up can take. The diameter in the equation is whatever is turning. If it's a lathe, then that would be the stock diameter. If it is a milling machine, it would be end mill diameter. Hope this helps. Take care. Keith
Great video, thanks for taking the time to make it, and I'm glad you're making enough off youtube that you have a little more wiggle room in your budget for end mills :)
I see you're cutting on a piece of scrap with lots of cutouts. May I suggest either clamp right to the spoilboard or a flat sheet with no cutouts? The reason being that when you get toward the bottom of the cut the stock can flex downward grabbing the end mill, either breaking it or runing surface finish.
I'd recommend a mister. Basically you are blowing away the chips with compressed air, and adding a tiny amount of lubricant tot he air. Industrial high speed mills (use small cutters) generally use misting. Your biggest problem there will be running a compressor the whole time.
Don't know if this will apply but when I cut openings in aluminum framed doors using a router and special cutter, I found that the aluminum would weld itself to the bit unless sprayed with a substance that would prevent this. What I ended up using was a "lemon scented" spray cleaner. The rotational speed of the bit was also critical. The combination of slower speed and the lemony cleaning solution solved the problem for me.
I attempted to cut out a simple 2.5" diam hole out of 1.25" thick 6061. I indexed, cut thru halfway with a 1/4" carbide tool, flipped the stock and ran the cut again. For a single side I left three 0.015" thick, 0.25" wide tabs (combined tab thickness 0.030"). All would have gone well but on the very last pass the router fought the Al and things got a little hairy. Three 30 thousands tabs are simply not enough. Going back I may have even stepped up to 5 tabs, or even "one continuous" tab and cut out the part by hand. (Setup: About 15ipm, DWP611 at full rpm, 0.05" depth of cut, almost continuous flooding/flushing and vacuuming of chips. I've also removed the waste board and the skeletal structure under, mounting everything to a stiffened 3/16" plate with 1/4-28 drill-tap in a 3" array for solid hold downs.)
+arkayic111 I find that when you're about to break through, upcut endmills tend to grab a bit more aluminum than you'd expect. Probably have to go in and slow down the last few passes, or just bite the bullet and plunge through at that point.
@Winston Moy I would try a single flute endmill with max rpm, light depths of cut .01 or less with with higher feed rate. I would start at .005 per rev and adjust up or down if needed. Also Use a light oil and not a heavy one. Try WD-40 or equivalent. Heavy oil does not remove heat fast enough for aluminum. Or if you can use a water soluble oil with a 8-10% concentrate with a spray bottle that would be best.
I mainly cut carbon fiber on my cnc and I found that when cutting 4mm the back plate that holds the spindle flexes a lot and I have to go really slow. A friend of mine who is a cnc and 3d printer wiz has access to a really big industrial cnc and he offered to cut me a new plate out of something like 1/4in aluminum. That is what I am going to do to fix that issue.
+RCflyer729 A good diy solution to this issue is to bolt (vertically) two strips of 15x15mm aluminium bar either side of the spindle mount clamp. Then also bolt the strips into the spindle mount itself. I have seen this on a few peoples shapeoko 3s and I am going to do it before I start tackling aluminium on mine!
+RCflyer729 I'm going to start in this world of CNC mills now. I intend also to cut carbon fiber and aluminum. How's your exeprience with CF so far? have you tried already aluminum? do you own the Shapeoko 3? are there any other more affordable CNCs out there? I'm starting my research now, sorry for many questions and thank you.
Daniel Souza I do have a shapeoko 3 and it works awesome for cutting cf. I did try aluminum and that worked well also but u just need to make sure and put some oil on the bit or it can bind up and jam. For carbon fiber I use these bits. www.ebay.com/itm/10-1-45mm-0571-DIAMOND-CUT-CARBIDE-ROUTER-BURRS-FT-Kyocera-Tycom-/151600984343?hash=item234c1f7117:m:mjIwpx8UV27UrlkIJgu-BhA personally I think the shapeoko 3 is an awesome machine and I recommend it but you might also want to check out the xcarve. It think the shapeoko 3 is cheaper though. Let me know if you have any more questions I would be glad to help.
Great Video! The Alloy type you use will have a big impact on you finish and how the machine cuts and behaves, some alloys can be a bit 'Gummy' and do tend to glog bits. If you want really nice cuts for parts of higher precision give a cast surface ground aluminium plate a try. Something like MIC6 or ATP-5. It may cost a little more but it's worth it and you get the advantage of having two parallel precision ground surfaces which can be great for mounting other parts onto while maintaining a high level of precision.
Hey Winston, I enjoyed your video. maybe you can do what i do on my industrial lathe and mill and use paraffin as a lubricant. It may be a bit messy at the higher revs but it works well for aluminium.
I used to work with a larger sturdier machine cutting front panels for rack mounted instrumentation. We used to use a mixture of about 3parts liquid paraffin to 1 part motor oil. Pretty messy but worked really well cutting with 3mm cutters through 3mm anodised panels. Same for engraving them. A scattering of sawdust around the shop floor soaked up the spray. Not so good in the home ;)
there is something in germany we call it glueing, if you are to slow the aluminum will "glue" so at work we cut aluminium with a spindle speed at 1800 and cooling (cooling is important against glueing - sorry dont know the english word for that - sticky?) but i think you have to look what kind of aluminum you have by the way NIce Video :)
Use the shortest end mill you can find to reduce vibration and shattering. ALWAYS use a spray mist of air an alcohol to lubricate the end mill and clear the chips from the cutter, this stops recutting of the chips which otherwise will deterate your edge finish. The alcohol stops build up from aluminium on the end mill. The rule is to actually cut aluminium and other soft metals with a high feed rate to avoid heat buildup in the end mill. Heat is the number one enemy of your cutters life. The rigidity of your machine, the power of the spindle and the quality of the end mill are the things determining how fast you can go. Your cuts actually look ok in the end considering the machine you're using. Alcohol and compressed air will make all the difference.
Hi Winston thanks for your videos. Just subscribed. Would you still recommend the Shapeoko 3 in July 2018. I like the size and pricing. This would be my first cnc but want a machine that I can grow into also. I like the XXL because of the size. Any other CNC I should look at? Thanks
Hello Winston, do you have any advise for engraving text on Aluminum. Need to engrave the text to a depth of .003 inches and the text size must be at least 0.125 inches high. I am using a 1/8" V bit. the Amana 45609. Not sure how to add the bit size into the library, Also how to adjust speeds and feeds. I was told that the Carbide Create program can not control the depth of a V cut. Thank you.
Great video. Would you recommend this machine for fabricating small alumnium, carbon fiber and cutting cystal materials? Or do I need a more expensive industrial grade CNC machine?
This will do all of those, though each one has its own requirements. CF, the big one is protecting your lungs. And all of them benefit greatly by using specialized cutters.
As for the chips if you build a vacuum driven dust shoe like the one I gave you a file for awhile back. You shouldn't have any problems with chip collection towards the end of the job. all the chips get sucked up as soon as they are created.
Hey Winston,thank's to sharing your talent,i also have a shapeoko 3 and i need to cut in aluminum but to be honest my english isn't perfect :p , can you give me a resume of what i need to do with the shapeoko, i understand the importance of the end mill,something with carbide would be perfect but the feedrate ? slow ? how much slow are we talking about ? thank's
At 2:24 you say ".01 inches depth-of-cut". At 3:35, "don't do simple profile cuts more than 1/2 diameter of the end mill". For a 1/8" dia end-mill that's a 6x difference. I'm new to CNC and I suspect you were referring to two different operations. But can you explain? Thanks.
Clarification: I meant total depth of cut should not exceed 1/2 EM diameter without extra room cut for chip clearing. Each individual pass should be done a the appropriate depth for your cutting parameters.
5 thousands is going off the far end in my opinion, but given it's a consumer grade machine, it's not bad for your typical DIYer. I may actually pick one of these up. Which size shapeoko do you have? (Or if anyone else knows)
+Marc Schaefermeyer Not yet, after my first few unsuccessful cuts, I went straight for more speed and power. I'll revisit with the DC spindle in the near future.
you could set up an air line with a small gas ball valve to control the pressure so it clears the chips but doesn't throw everything all over the place but with aluminum coolant is really the best option
Thanks for this very informative video! Would a 500W spindle with 15.000 rpm max work for alumnium? What bit/feedrate/spindlespeed etc. would you recommend I try with?
+sttrife difficult to say. The power rating on DC spindles aren't usually a good indication of torque. Aluminum doesn't always cut best at maximum RPM, and if your spindle doesn't have closed loop speed control it can get bogged down and even stall. You could probably get away with the 500W, but you may need to take conservative cuts. Check the Shapeoko wiki regarding materials for suggested feeds and speeds as a starting point (I'd go with the Nomad's settings first, since that assumes a weaker spindle). Most 2-3 flute endmills will work, best if they're designed for aluminum though. 45 degree helix angle and/or ZrN coating.
If you have the possibility to add mist to your machine it would help a lot. In that way you get oil to your cutting tool as well as chip evacuation due to the pressurised air. This will mess up your wood base over time, but alternatively you make another base plate in aluminium !!
Winston, thanks a lot for sharing your knowledge, I would like u to give me some impressions about the x carve, I'm planning to buy, specifically about the spindle, is the default option (dw611) a good one?, powerfull enough to cut alumminum or engraving other metals?, I'm concerned about noise, power and speed rates, thanks a lot for your comments
+Miguel Ideador The spindle has more than enough power to saturate what NEMA 23's are capable of pushing it through, so that won't be a limiting factor. The minimum RPM is around 16k, but so far I haven't had any issues with that being too high. I haven't tried it with plastics though. With wood it's fine. As for noise... well... you're SOL there. This thing wails like a shop vac. And that's before you start cutting into any material.
+Rob Graff With conservative speed settings that put very little stress on the machine, probably a little smaller than 1/8" tall letters. Taking the time to tune your belts and everything, perhaps smaller than 0.1" reliably. It's something I'll be testing in the coming weeks.
makezine.com/2015/11/04/digital-fabrication-shootout-winners/ For wood, any of the CNCs recommended by Make are good, but for metal, especially larger projects, Shapeoko is best value for sure.
thanks for sharing this video! I made my own cnc, but i wasn"t shure if i could do aluminium as well. But i think my design of cnc is even stronger than a shapeoko, so i'm going to try aluminium too. Woul be great if i can do that too. Thanks for the warnings and personal experience. ;-)
it wasn't as hard as i expected. That will be beginner's luck i guess :p . I made a lot of mistakes though and i'm allready thinking of rebuilding my machine with some major corrections. Good thing is now i can use this cnc to do the perfect measurements and cuttings, so it will be easier this time. :-)
:o when i chuck a piece aluminum on my lathe or on the milling machine at work, i use rubbing alcohol as coolant. Compared to oil, it's much less messier and the chips would fly off more easily
I have made slotting cuts with 1/8" cutters as deep as 15mm in aluminium (in small steps of 0,5mm), it helped cooling it with methylated spirits (or something similar). It suspends the chips and cools the part so it doesn't clog up. But the stiffness really seems to be a big problem with this machine, the flex you show in the video is really not tolerable. Maybe it's the chatter, that makes your bits break?
+Klaufmann part of the problem was the machine not being *perfectly* level, and some of it was the weak DC spindle I started with. I have since gotten better results going slow and steady.
Yeah, especially with simple CNC routers that aren't very stiff there are lot's of adjustments to make, I notice that on my machine myself. The leveling and alignment also isn't that trivial, because the components are often not perfectly straight or can sag because of the weight. I can measure a sag of roughly 0,1mm to the middle of the table, because I use 20mm unsupported rails. If I face a part and hold an straight edge (or in my case a metal ruler) against the light on the surface I can make out a clear gap in the middle and a touching spot on each end. However, I use a ~1kW Kress spindle and that makes a huge difference. I also noticed that it is sometimes better to use a bigger endmill because it is more rigid.
Alcohol mixed with water at a ratio of 30% Alcohol and 70% Water works very well for aluminum. The alcohol cools the material much better than water and the water is sufficient to keep from any possible combustion if heat does build up. Plus the alcohol helps evaporate the liquid and reduces oxidization.
urjnlegend ... that would be a nope. many use a much higher alcohol to water ratio and is safe. combustion requires specific fuel to air ratios and wth the introduction of the water it throws that potential out.
Use very short 1 flute bits for aluminum. The single flute improves chip clearing (which you accurately pointed out as a huge priority for routers in aluminum) significantly. And the short bits give you similar rigidity to thicker bits. wcproducts.net sells fantastic single flute bits. You won't regret it.
Hello winston, I am ready to do aluminum cutting. my sock is 3/16" thick - it is not 6061 but 50-52 - I am new never cut anything yet just bought a SO3 XXL and been learning. pls help me tell me what is the speed for spindle and punch rate, how many inch per minute. I have a water cool spindle 800W -1.5 KW
I honestly don't have a good point of reference for you. 5052 isn't supposed to be very good at machining (www.shapeoko.com/wiki/index.php/Materials#Aluminium). I would try the "official" feedrates recommended (www.shapeoko.com/wiki/index.php/Materials#Official_Feeds_and_Speeds), make sure you have a coated endmill, and cutting fluid. If that doesn't work, adjust your cutting parameters from there, faster/slower. I can't advise you which way to go, as you're well and truly in unknown territory. Unless you really need 5052, I would abandon it and get some 6000 or 7000 series material.=
hi m8, working in alu, polish, drilling cutting etc. use methylated spirits... it looks you are using some kind of normal oil there ? :-) thanks for sharing
+Tome4kkkk With the right endmill, likely yes. Check out: th-cam.com/video/iOgS626gK1Y/w-d-xo.html to see someone pushing their machine to the limit. 2" is too deep to cut a straight profile, but for a bowl-like shape, shouldn't be a problem.
Most people will be surprised, but Aluminium needs more cooling and chip removal than steel. It melts already at 660° Celsius and gets soft very quick. Also the chip removal is VERY IMPORTANT!!!
WD40 is great to prevent chip weld. If you have a coolant mister, you can bypass WD40, because you're keeping the endmill, as well as the aluminum cool enough to prevent chip weld.
I also went through a lot of trouble with cutting AL. Here are the main game changers: 1. Single flute endmill. Nothing fancy, $17 for 10: www.amazon.com/gp/product/B07F35WQYG/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 2. Air blower, again nothing fancy, just a regular compressor with a jet blower. 3. Motor with closed-loop, like MKS SERVO42B, so steps are not getting skipped. I can easily cut 5mm thick AL with 1/8" end mill. Speed is 500mm/min, spindle 10000, DOC 0.5mm.
and you can watch my videos where I'm cutting 3/8" thick 6061 aluminum. I'm using a 1/8" carbide 4 flutes endmill at very conservative surface speed and feed. My depth of cut was 1 mm. Which is aggressive compared to yours. LOL
I know this is from a LONG time ago but I saw right off the hop that one issue you had was using a cutter with only 1 flute. Even on wood I have found they suck donkey balls.
Yes, so usually you have to go *very* light is cutting with a 1/8" end mill. But honestly I don't like going larger than a 1/16" if I'm using a Dremel. And even then, you'll be near full power just to get it to work.
As far as i could tell until the end of this video you were conventional cutting everything. It's best to climb cut for the cleanest finish. If you want to climb cut you want to go clockwise on the outside of a part and counterclockwise on the inside of a part (This is assuming that your spindle is spinning clockwise.) this gives you the best finish for any type of job not just aluminum.
Know what works wonderfully well? ATF. Yes, automatic transmission fluid as it is meant to not breakdown with heat like an oil since oil is 3k-5k miles per change and ATF is 50k-100k depending.
Clean cutting aluminium .......... use the better , stiffer grades if you can , they tend to be less chewy & will chip , rather than heat up & fuse to the cutter . If you want small detail , requiring small cutters running a high speed build a plastircine or wax wall round it & use "suds" or milk ( the fat lubricates the cutter , the water cools it ) . Messy , but may save broken cutters . There is silicon spray , which is often used for circular blades , would would help to stop pick up on the cutter . A thought , may be plumber freezing spray ( relatively cheap ) & use candle wax or oil as the lub , less messy than milk .
Increase rigidity anyway you can, maybe you could goto a double gantry design, reduce spindle overhang, use shortest endmil possible, raise work piece and reduce spindle speed.
+Winston Moy it's more than that, less Z travel means more rigidity which means more performance potential, faster feed, faster spindle, deeper, wider cut, it all starts with rigidity.
Get the machinist calculator app. It will tell you that 30-40ipm is your cutting range. Regardless if you have a 20k-30,000rpm spindle it’s too fast. Cutting aluminum doesn’t need to occur over 8000rpm on any machine so if you can’t slow it down without losing torque change the spindle. If your gantry can support it start with a minimum 3kw spindle or beef the gantry up so it can support it. Anything smaller is probably going to chatter, break end mills, or require triple the time simple skimming the part until it’s made. Who’s got the time for that?
Hi Winston, really enjoying your videos, keep it up! I've cut aluminum sheets (3mm) with my shapeoko 2 with relative reliable results. Here is an example of a battery holder for my robot: th-cam.com/video/JGuEo9QiW4s/w-d-xo.html I usually use a 2 flute, 2mm endmill with my Kress 800 fme-q spindle, speed set to 5 (~28000 rpm if I recall correctly). DOC 0.2mm, feedrate 600mm, step over 0.4, and width of cut for a profile cut set to 2.5mm (two passes to clear chips more easily). Also using a bit of WD40 to cool the bit. I lost a couple of bits also, but mostly because of user errors :) Cheers, Alex
Hi sorry for my english. 1 Thing normaly you do not lubricate by cutting aluminium. you have too cool ist for exymple by alkohol. becouse if alu get warm it became smother and clamp your bit
use 2 flutes, i would say use a single flute but they are prone to breaking specially the small ones, I have uses 2 flute and abused it on my tiny machine and got away without breaking anything.
Wow, I find that anything faster than 4 inches per minute on a 1/8" end mill results in a broken bit. On a 1/16 inch end mill,2 inches per minute max. This is with a depth of cut of 0.02 inches and an overlap of 30%. Since I went to these speeds I have been able to produce 30 large intricate pieces for a product of mine, without a single broken bit . why the big discrepancy?
+Tom B Spindle speed could be a big factor. I'm cutting at upwards of 20k RPM, and at about half your depth of cut. So it's kind of an inverse relationship, go fast and shallow, or deeper and slower... #twss
Be careful when Milling aluminum it shrinks .0005 when it cools, I do 2 finishing passes with a higher rpm with less doc to get a nice surface finish i also just use a compressor with an attached air nozzle to cool my part while cutting.
Not when you cool it enough ;) I use methylated spirits for cooling and lubrication. But yes, finishing passes are really good to improve the surface finish.
I'm a CNC machinist by trade. I program gcode for Haas CNC mills both manually by hand and using cam software to complement more complex features. We cut mostly 6061, and we HOG it.
There are a few key things I've learned over the years:
1) RADIAL ENGAGEMENT (this is the #1 source for the difference between a good or bad cut) - the amount of the diameter of the cutter that is engaged with the material being cut. The more the material wraps around the cutter, the less time the cutter has to cool off between cuts, and less opportunity for chips to leave the cutting area. I like between 5-25% engagement depending on diameter of the cutter. Keep in mind that not all cutters are made the same, and the simple act of plunging can ruin some cutters no matter what you try (it's often better to ramp down at an angle or Helix into part instead of plunging in z-axis only)
2) chip evacuation - both in the cutter and on the workpiece. If the cutter begins to re-cut chips it already removed from the material, it will develop premature wear and/or chip a cutting edge or break. If there isn't proper room for the chip to exit the relief area of the cutter, the cutter will clog up and begin the welding process.
2.5) cutter geometry (WOW)... This one is somewhat really important. Aluminum LOVES non-coated high polish solid carbide end mills with a sharp edge and a margin after cutting edge (to prevent the cutter pulling itself into material off-axis of rotation) as well as a high Helix. We run between 30-45deg Helix normally, and the only exception is extra long tooling. we are currently running a job that uses a custom ground .125" dia by 5/8" length of cut end Mill that we will probably have to shorten up because of chatter
3) coolant - well not really. It helps tremendously when you are taking deep and fast cuts with large stepovers, but if you learn from bullet point (1) then you will realize coolant helps but is not a king pin requirement. Coolant allows you to cross that radial/heat buildup issue by transferring heat away. Keeping radial engagement in your mind when programming toolpaths will relegate coolant's job more to long term tool life rather than short term (we have had 1/2" end mills that ran for 2+ years @ 40hrs/WK at a material removal rate of 20+ cubic inches per minute; that's 200,000 cubic inches of material a month as waste material in chips if I did mental math right)
4) rigidity - you mentioned this in your video. Pretty much is a basic tenet of machining. Good clean cuts require rigid machines and tools (most of the time; some operations benefit from some slight flexing but that's another topic).
I didn't mean this post to end up so long. I got carried away sharing my knowledge from my passion/profession... Lol
Good luck to you, and I hope I helped future endeavors.
All fantastic information. No amount of internet research can replace experience.
I'm actually a little curious now about what cases you think tool/machine deflection isn't a purely negative behavior...
when chasing an existing hole, using a rigid tool where the 2nd drill doesn't line up precisely leads to heavier engagement on one side of the tool. Using high speed steel tools (or flex in the machine frame) can allow the tool to flex without breaking. A solid carbide tool (especially a smaller tool size) in a rigid machine could break off in the hole because it is hard yet brittle and does not like flexing. This could swing the other way also, as too much movement could also allow the 2nd tool to bind in the hole.
Deflection in carbide tools = breaking, chipping, edge wearing. Simply put, if carbide is engaged with work material and it's not cutting the material, then it's bad news bears.
There are cases where a tap would benefit from less rigidity. Google "tapmatic" units (I think I got the spelling right). They have a special tool holding assembly that allows the tool to move off axis while still being straight (like the couplers that connect the stepper motors to the lead screws on other router tables)
I can't think of any other situations at the moment. Typically rigidity is best
I just printed this comment out, and posted it on my refrigerator. Highest complements.
Comments from passionate professionals are often very good. Dense with information. Yours definitely is well appreciated by me, and I imagine anyone who is thinking about cutting aluminum or has started to and is having difficulty. Its one thing to think you have an idea what is going on, and another to have your suspicions confirmed by a pro.
Great video as usual Winston!
I've been cutting quite a bit of Aluminum with my heavily modified Shapeoko 2; I've gone as thick as 3/8 and would feel comfortable going thicker. Also, I use a dust shoe and cut with no lubricant. I found that the lubricant just causes chips to not be picked up by the dust shoe.
The thing I noticed in the video that I do differently relates to tabs. Say, on a job where I am making a bracket, which bolts to something, I break the gcode into two files.
1. The bracket bolt holes.
2. The bracket outer profile.
Assuming you don't lose 0, 0, 0 (x, y, z) between jobs and there is a waste board below your aluminum, you eliminate the need for tabs.
Step 1. Secure your aluminum sheet
Step 2. Cut job 1 (the bolt holes)
Step 3. Move your gantry clear of the bolt holes cut in Step 2 (retaining 0, 0, 0; but keeping the motors locked)
Step 4. Use self-tapping screws to secure what will become the bracket, by putting a self-tapping screw into each of the bolt holes created in Step 2
Step 5. Cut job 2 (the outer profile)
I can't stand the little imperfections created by tabs. Though, in the case where you don't have holes in the middle of the piece, you are forced to use tabs :/
Hope this is helpful!
Sounds basic, but real genius re using bolt (or screw) holes to anchor workpiece.
For aluminum in the Linamar Plants in Canada we used Varsol in a spray bottle to cool the carbide cutters while cutting Aluminum Chevy V-6 water pumps. It work very well. I found that the way my Machine was setup the the first month of running it was to slow and could never get a mirror like finish that was needed for Quality Control so i dial indicated the 12 cutter in the cutting head which removed the vibration, it was a old manual machine. I picked the lowest cutter and shimmed all the rest to match it, then i double the feed and RPM's of the tool and that allowed me to double my hourly out put with a mirror like finish. this got me a raise and allowed me to do my own machine setups after that. That was 38 years ago. Try using conventional cutting when using the Shapeoko 3 because the light frame is like having backlash problems when using small flexible cutters Climb cutting pushes the cutting edge away from the stock and conventional draws the tool edge closer to the material which gives a more controlled size and needs less spring cuts do to tool flex.
Winston, I enjoy your video and appreciate your knowledge and talent. You are making a impact on the world.....keep it up.
If you will take smaller cuts you can greatly increase your feed rate. Try doing cuts at .025-.05 I know it seems like deeper cuts would be faster but it's not. You get the highest material removal rate with high feed rate /small DOC(depth of cut) This style is one of the major contributors to high speed machining. You can also save a lot of endmills by cutting your stock to smaller sizes and profile the part instead of the slot cut your doing. Slots and pockets are the hardest on your tools especially when you don't have coolant. Compressed air will serve you better than the oil you are using. Chip removal is more important than heat in this case.
On my CNC router ( my design and build), I also use the Dewalt router as shown in your video and I also run it at about 80% of it Max RPM. But, I use 1/8" single flute end mills that I buy from drillman on eBay, at 20 Inches per minute, and a .030" depth of cut. As you have found, a good blast of air to clear the chips is a must or they will weld to your cutter and break it. I do not use any coolant - just air. I have cut up to 1/2" aluminum this way without cutting a wider channel first for chip clearance.
A good starting point for speeds and feeds is : cutter speed ( you can look up the cutter speed value for any given material in the "Machineries Handbook" ) X 4 divided by diameter .
Back off on the speeds and feeds for your first run, then increase to see how much the project / set up can take.
The diameter in the equation is whatever is turning. If it's a lathe, then that would be the stock diameter. If it is a milling machine, it would be end mill diameter.
Hope this helps.
Take care.
Keith
If you are going to cut Aluminum I would suggest swapping the MDF board out below it and move to a Acrylic waste board and use coolant.
Probably because MDF will absorb the liquid coolant and deform. Wood and liquid doesn't mix!
Great video, thanks for taking the time to make it, and I'm glad you're making enough off youtube that you have a little more wiggle room in your budget for end mills :)
I see you're cutting on a piece of scrap with lots of cutouts. May I suggest either clamp right to the spoilboard or a flat sheet with no cutouts? The reason being that when you get toward the bottom of the cut the stock can flex downward grabbing the end mill, either breaking it or runing surface finish.
I'd recommend a mister. Basically you are blowing away the chips with compressed air, and adding a tiny amount of lubricant tot he air. Industrial high speed mills (use small cutters) generally use misting. Your biggest problem there will be running a compressor the whole time.
Don't know if this will apply but when I cut openings in aluminum framed doors using a router and special cutter, I found that the aluminum would weld itself to the bit unless sprayed with a substance that would prevent this. What I ended up using was a "lemon scented" spray cleaner. The rotational speed of the bit was also critical. The combination of slower speed and the lemony cleaning solution solved the problem for me.
When I see that you got it to work, I know it can be done. Thanks for sharing.
Lots of very useful info for people wanting to get the most out of their desktop hobby CNC machines. Thanks!
I attempted to cut out a simple 2.5" diam hole out of 1.25" thick 6061. I indexed, cut thru halfway with a 1/4" carbide tool, flipped the stock and ran the cut again. For a single side I left three 0.015" thick, 0.25" wide tabs (combined tab thickness 0.030"). All would have gone well but on the very last pass the router fought the Al and things got a little hairy. Three 30 thousands tabs are simply not enough. Going back I may have even stepped up to 5 tabs, or even "one continuous" tab and cut out the part by hand. (Setup: About 15ipm, DWP611 at full rpm, 0.05" depth of cut, almost continuous flooding/flushing and vacuuming of chips. I've also removed the waste board and the skeletal structure under, mounting everything to a stiffened 3/16" plate with 1/4-28 drill-tap in a 3" array for solid hold downs.)
+arkayic111 I find that when you're about to break through, upcut endmills tend to grab a bit more aluminum than you'd expect. Probably have to go in and slow down the last few passes, or just bite the bullet and plunge through at that point.
@Winston Moy I would try a single flute endmill with max rpm, light depths of cut .01 or less with with higher feed rate. I would start at .005 per rev and adjust up or down if needed. Also Use a light oil and not a heavy one. Try WD-40 or equivalent. Heavy oil does not remove heat fast enough for aluminum. Or if you can use a water soluble oil with a 8-10% concentrate with a spray bottle that would be best.
Hey Winston. I just want to say that I really enjoy your channel.
This video was perfectly worded and articulate. Very nice work!
I mainly cut carbon fiber on my cnc and I found that when cutting 4mm the back plate that holds the spindle flexes a lot and I have to go really slow. A friend of mine who is a cnc and 3d printer wiz has access to a really big industrial cnc and he offered to cut me a new plate out of something like 1/4in aluminum. That is what I am going to do to fix that issue.
+RCflyer729 A good diy solution to this issue is to bolt (vertically) two strips of 15x15mm aluminium bar either side of the spindle mount clamp. Then also bolt the strips into the spindle mount itself. I have seen this on a few peoples shapeoko 3s and I am going to do it before I start tackling aluminium on mine!
+RCflyer729 I'm going to start in this world of CNC mills now. I intend also to cut carbon fiber and aluminum. How's your exeprience with CF so far? have you tried already aluminum? do you own the Shapeoko 3? are there any other more affordable CNCs out there? I'm starting my research now, sorry for many questions and thank you.
Daniel Souza
I do have a shapeoko 3 and it works awesome for cutting cf. I did try aluminum and that worked well also but u just need to make sure and put some oil on the bit or it can bind up and jam. For carbon fiber I use these bits.
www.ebay.com/itm/10-1-45mm-0571-DIAMOND-CUT-CARBIDE-ROUTER-BURRS-FT-Kyocera-Tycom-/151600984343?hash=item234c1f7117:m:mjIwpx8UV27UrlkIJgu-BhA
personally I think the shapeoko 3 is an awesome machine and I recommend it but you might also want to check out the xcarve. It think the shapeoko 3 is cheaper though. Let me know if you have any more questions I would be glad to help.
Great Video! The Alloy type you use will have a big impact on you finish and how the machine cuts and behaves, some alloys can be a bit 'Gummy' and do tend to glog bits. If you want really nice cuts for parts of higher precision give a cast surface ground aluminium plate a try. Something like MIC6 or ATP-5. It may cost a little more but it's worth it and you get the advantage of having two parallel precision ground surfaces which can be great for mounting other parts onto while maintaining a high level of precision.
That was a great review. Concise and unbiased.
Hey Winston, I enjoyed your video. maybe you can do what i do on my industrial lathe and mill and use paraffin as a lubricant. It may be a bit messy at the higher revs but it works well for aluminium.
I used to work with a larger sturdier machine cutting front panels for rack mounted instrumentation. We used to use a mixture of about 3parts liquid paraffin to 1 part motor oil. Pretty messy but worked really well cutting with 3mm cutters through 3mm anodised panels. Same for engraving them. A scattering of sawdust around the shop floor soaked up the spray. Not so good in the home ;)
Very well explained with practical problem demo
Winston, awesome video (as always).
Happy Holidays!!!
+TheRangeControl Thank you, sir. Happy holidays to you as well.
why dont you upload any more? i need your content dude
there is something in germany we call it glueing, if you are to slow the aluminum will "glue" so at work we cut aluminium with a spindle speed at 1800 and cooling (cooling is important against glueing - sorry dont know the english word for that - sticky?)
but i think you have to look what kind of aluminum you have by the way NIce Video :)
chip welding
"Gummy."
You are welcome.
Use the shortest end mill you can find to reduce vibration and shattering. ALWAYS use a spray mist of air an alcohol to lubricate the end mill and clear the chips from the cutter, this stops recutting of the chips which otherwise will deterate your edge finish. The alcohol stops build up from aluminium on the end mill. The rule is to actually cut aluminium and other soft metals with a high feed rate to avoid heat buildup in the end mill. Heat is the number one enemy of your cutters life. The rigidity of your machine, the power of the spindle and the quality of the end mill are the things determining how fast you can go. Your cuts actually look ok in the end considering the machine you're using. Alcohol and compressed air will make all the difference.
Hi Winston thanks for your videos. Just subscribed. Would you still recommend the Shapeoko 3 in July 2018. I like the size and pricing. This would be my first cnc but want a machine that I can grow into also. I like the XXL because of the size. Any other CNC I should look at? Thanks
Hello Winston, do you have any advise for engraving text on Aluminum. Need to engrave the text to a depth of .003 inches and the text size must be at least 0.125 inches high. I am using a 1/8" V bit. the Amana 45609. Not sure how to add the bit size into the library, Also how to adjust speeds and feeds. I was told that the Carbide Create program can not control the depth of a V cut. Thank you.
Thank you Winston for a great video, I am learning a lot watching your work!
Great video. Would you recommend this machine for fabricating small alumnium, carbon fiber and cutting cystal materials? Or do I need a more expensive industrial grade CNC machine?
This will do all of those, though each one has its own requirements. CF, the big one is protecting your lungs. And all of them benefit greatly by using specialized cutters.
As for the chips if you build a vacuum driven dust shoe like the one I gave you a file for awhile back. You shouldn't have any problems with chip collection towards the end of the job. all the chips get sucked up as soon as they are created.
Hi winston thanks for the video and information! Again very helpful!
Hey Winston,thank's to sharing your talent,i also have a shapeoko 3 and i need to cut in aluminum but to be honest my english isn't perfect :p , can you give me a resume of what i need to do with the shapeoko, i understand the importance of the end mill,something with carbide would be perfect but the feedrate ? slow ? how much slow are we talking about ? thank's
Good experience & infos shared..thank you bro..thanks to other experience experts chipping the bonus comments 💕love u all.
At 2:24 you say ".01 inches depth-of-cut". At 3:35, "don't do simple profile cuts more than 1/2 diameter of the end mill". For a 1/8" dia end-mill that's a 6x difference. I'm new to CNC and I suspect you were referring to two different operations. But can you explain? Thanks.
Clarification: I meant total depth of cut should not exceed 1/2 EM diameter without extra room cut for chip clearing. Each individual pass should be done a the appropriate depth for your cutting parameters.
How does the number of flutes affect things?
5 thousands is going off the far end in my opinion, but given it's a consumer grade machine, it's not bad for your typical DIYer. I may actually pick one of these up. Which size shapeoko do you have? (Or if anyone else knows)
Did you try using different fluted endmills, and if so did you notice a different in chip clearing, for example with a 4 flute instead of a 2 flute?
+Winston Moy what did you see between the two eighth inch endmills?
Awesome video!
thanks!
thanks for sharing, great video as usual
Did you ever get it to work with the Quite Cut Spindle?
+Marc Schaefermeyer Not yet, after my first few unsuccessful cuts, I went straight for more speed and power. I'll revisit with the DC spindle in the near future.
+Winston Moy awesome. That's what I kind of figured.
you could set up an air line with a small gas ball valve to control the pressure so it clears the chips but doesn't throw everything all over the place but with aluminum coolant is really the best option
Very informative videos Winston. Well done, thank you!
Love your videos..please where can I get that RPM meter,gage..link of where or at least a brand with model
Thanks for this very informative video! Would a 500W spindle with 15.000 rpm max work for alumnium? What bit/feedrate/spindlespeed etc. would you recommend I try with?
+sttrife difficult to say. The power rating on DC spindles aren't usually a good indication of torque. Aluminum doesn't always cut best at maximum RPM, and if your spindle doesn't have closed loop speed control it can get bogged down and even stall. You could probably get away with the 500W, but you may need to take conservative cuts.
Check the Shapeoko wiki regarding materials for suggested feeds and speeds as a starting point (I'd go with the Nomad's settings first, since that assumes a weaker spindle). Most 2-3 flute endmills will work, best if they're designed for aluminum though. 45 degree helix angle and/or ZrN coating.
If you have the possibility to add mist to your machine it would help a lot. In that way you get oil to your cutting tool as well as chip evacuation due to the pressurised air. This will mess up your wood base over time, but alternatively you make another base plate in aluminium !!
Winston, thanks a lot for sharing your knowledge, I would like u to give me some impressions about the x carve, I'm planning to buy, specifically about the spindle, is the default option (dw611) a good one?, powerfull enough to cut alumminum or engraving other metals?, I'm concerned about noise, power and speed rates, thanks a lot for your comments
+Miguel Ideador The spindle has more than enough power to saturate what NEMA 23's are capable of pushing it through, so that won't be a limiting factor.
The minimum RPM is around 16k, but so far I haven't had any issues with that being too high. I haven't tried it with plastics though. With wood it's fine.
As for noise... well... you're SOL there. This thing wails like a shop vac. And that's before you start cutting into any material.
I just watched this dude, thanks for the information.
Great video mate. Great info. I have just started doing cnc video on big scale machine.
@Winston Moy. How small of letter's & number's do you think you could engrave on aluminum with your CNC?
+Rob Graff With conservative speed settings that put very little stress on the machine, probably a little smaller than 1/8" tall letters. Taking the time to tune your belts and everything, perhaps smaller than 0.1" reliably. It's something I'll be testing in the coming weeks.
Which CNC would you prefer for wood as well metal Diy projects. With a better software , however I'm a Architect well know of auto cad and 3ds Max.
makezine.com/2015/11/04/digital-fabrication-shootout-winners/
For wood, any of the CNCs recommended by Make are good, but for metal, especially larger projects, Shapeoko is best value for sure.
thanks for sharing this video! I made my own cnc, but i wasn"t shure if i could do aluminium as well. But i think my design of cnc is even stronger than a shapeoko, so i'm going to try aluminium too. Woul be great if i can do that too. Thanks for the warnings and personal experience. ;-)
Wim Meeus was it hard to build?
it wasn't as hard as i expected. That will be beginner's luck i guess :p . I made a lot of mistakes though and i'm allready thinking of rebuilding my machine with some major corrections. Good thing is now i can use this cnc to do the perfect measurements and cuttings, so it will be easier this time. :-)
do you think gold and silver behave like aluminum? i ask because i still don't have my nomad 4 weeks processing time.
Sometimes yes, but very often no. See: th-cam.com/video/rm-qSytjFnI/w-d-xo.html
:o when i chuck a piece aluminum on my lathe or on the milling machine at work, i use rubbing alcohol as coolant. Compared to oil, it's much less messier and the chips would fly off more easily
I have made slotting cuts with 1/8" cutters as deep as 15mm in aluminium (in small steps of 0,5mm), it helped cooling it with methylated spirits (or something similar). It suspends the chips and cools the part so it doesn't clog up. But the stiffness really seems to be a big problem with this machine, the flex you show in the video is really not tolerable. Maybe it's the chatter, that makes your bits break?
+Klaufmann part of the problem was the machine not being *perfectly* level, and some of it was the weak DC spindle I started with. I have since gotten better results going slow and steady.
Yeah, especially with simple CNC routers that aren't very stiff there are lot's of adjustments to make, I notice that on my machine myself. The leveling and alignment also isn't that trivial, because the components are often not perfectly straight or can sag because of the weight. I can measure a sag of roughly 0,1mm to the middle of the table, because I use 20mm unsupported rails. If I face a part and hold an straight edge (or in my case a metal ruler) against the light on the surface I can make out a clear gap in the middle and a touching spot on each end.
However, I use a ~1kW Kress spindle and that makes a huge difference. I also noticed that it is sometimes better to use a bigger endmill because it is more rigid.
Alcohol mixed with water at a ratio of 30% Alcohol and 70% Water works very well for aluminum. The alcohol cools the material much better than water and the water is sufficient to keep from any possible combustion if heat does build up. Plus the alcohol helps evaporate the liquid and reduces oxidization.
Rodney Reynolds sounds like a recipe for an explosion.
urjnlegend ... that would be a nope. many use a much higher alcohol to water ratio and is safe. combustion requires specific fuel to air ratios and wth the introduction of the water it throws that potential out.
Try using cutting oil with compressed air. Results be just amazing
using polished endmills may work better when using little to no coolant
Use very short 1 flute bits for aluminum. The single flute improves chip clearing (which you accurately pointed out as a huge priority for routers in aluminum) significantly. And the short bits give you similar rigidity to thicker bits. wcproducts.net sells fantastic single flute bits. You won't regret it.
Hello winston, I am ready to do aluminum cutting. my sock is 3/16" thick - it is not 6061 but 50-52 - I am new never cut anything yet just bought a SO3 XXL and been learning. pls help me tell me what is the speed for spindle and punch rate, how many inch per minute. I have a water cool spindle 800W -1.5 KW
I honestly don't have a good point of reference for you. 5052 isn't supposed to be very good at machining (www.shapeoko.com/wiki/index.php/Materials#Aluminium). I would try the "official" feedrates recommended (www.shapeoko.com/wiki/index.php/Materials#Official_Feeds_and_Speeds), make sure you have a coated endmill, and cutting fluid. If that doesn't work, adjust your cutting parameters from there, faster/slower. I can't advise you which way to go, as you're well and truly in unknown territory. Unless you really need 5052, I would abandon it and get some 6000 or 7000 series material.=
Thank You for the info
Climb cuts seem to perform much better than conventional cuts for a good edge finish on aluminium!
For a lubricant try using methylated spirits as cools the bit and lubricants as well apply by a spray bottle.
Sounds like a great way to have a shop fire to me.
hi m8, working in alu, polish, drilling cutting etc. use methylated spirits... it looks you are using some kind of normal oil there ? :-)
thanks for sharing
Do you have a machine like this one for sale?
Can you cut 3D shapes with SO3 in Al? I mean, like an aluminium mold 2 in deep for example. Layer by layer of course.
+Tome4kkkk With the right endmill, likely yes. Check out: th-cam.com/video/iOgS626gK1Y/w-d-xo.html to see someone pushing their machine to the limit.
2" is too deep to cut a straight profile, but for a bowl-like shape, shouldn't be a problem.
Winston Moy Thank you!
Eliminating backlash helps alot too!
Thanks Winston!
Very instructive. Thanks for sharing!!
So is their a way to attach a high power jet to it?
Most people will be surprised, but Aluminium needs more cooling and chip removal than steel. It melts already at 660° Celsius and gets soft very quick. Also the chip removal is VERY IMPORTANT!!!
what exactly is "80% power" in rpm?
WD40 is great to prevent chip weld. If you have a coolant mister, you can bypass WD40, because you're keeping the endmill, as well as the aluminum cool enough to prevent chip weld.
I also went through a lot of trouble with cutting AL. Here are the main game changers: 1. Single flute endmill. Nothing fancy, $17 for 10: www.amazon.com/gp/product/B07F35WQYG/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 2. Air blower, again nothing fancy, just a regular compressor with a jet blower. 3. Motor with closed-loop, like MKS SERVO42B, so steps are not getting skipped. I can easily cut 5mm thick AL with 1/8" end mill. Speed is 500mm/min, spindle 10000, DOC 0.5mm.
and you can watch my videos where I'm cutting 3/8" thick 6061 aluminum. I'm using a 1/8" carbide 4 flutes endmill at very conservative surface speed and feed. My depth of cut was 1 mm. Which is aggressive compared to yours. LOL
I know this is from a LONG time ago but I saw right off the hop that one issue you had was using a cutter with only 1 flute. Even on wood I have found they suck donkey balls.
hi winston i have one quastion : what size of milling bit can i use with dremel 3000
Dremels usually accept anything with a 1/8" shank.
yea but if isnt it power demanding for drill
Yes, so usually you have to go *very* light is cutting with a 1/8" end mill. But honestly I don't like going larger than a 1/16" if I'm using a Dremel. And even then, you'll be near full power just to get it to work.
Excellent video
As far as i could tell until the end of this video you were conventional cutting everything. It's best to climb cut for the cleanest finish. If you want to climb cut you want to go clockwise on the outside of a part and counterclockwise on the inside of a part (This is assuming that your spindle is spinning clockwise.) this gives you the best finish for any type of job not just aluminum.
+Zwcky101 Meshcam defaults to Climb milling, I hadn't bothered setting it for the early jobs in MakerCAM.
try crisco as a cutting fluid. just a light coating on the stock.
Know what works wonderfully well? ATF. Yes, automatic transmission fluid as it is meant to not breakdown with heat like an oil since oil is 3k-5k miles per change and ATF is 50k-100k depending.
Clean cutting aluminium .......... use the better , stiffer grades if you can , they tend to be less chewy & will chip , rather than heat up & fuse to the cutter . If you want small detail , requiring small cutters running a high speed build a plastircine or wax wall round it & use "suds" or milk ( the fat lubricates the cutter , the water cools it ) . Messy , but may save broken cutters . There is silicon spray , which is often used for circular blades , would would help to stop pick up on the cutter . A thought , may be plumber freezing spray ( relatively cheap ) & use candle wax or oil as the lub , less messy than milk .
Increase rigidity anyway you can, maybe you could goto a double gantry design, reduce spindle overhang, use shortest endmil possible, raise work piece and reduce spindle speed.
+Adam Hill All valid points. Never thought about raising the work piece, but when you're chasing every last thou of precision, it makes sense...
+Winston Moy it's more than that, less Z travel means more rigidity which means more performance potential, faster feed, faster spindle, deeper, wider cut, it all starts with rigidity.
I’m about to finish my diy CNC mill. Well I think this video have to watch before I start using it . Very helpful. Thx
Use kerosine as a coolant mix it pipe cutting oil.the endmill melts the aluminum to the cutting edge. This coolant will stop most of that.
Get the machinist calculator app. It will tell you that 30-40ipm is your cutting range. Regardless if you have a 20k-30,000rpm spindle it’s too fast. Cutting aluminum doesn’t need to occur over 8000rpm on any machine so if you can’t slow it down without losing torque change the spindle. If your gantry can support it start with a minimum 3kw spindle or beef the gantry up so it can support it. Anything smaller is probably going to chatter, break end mills, or require triple the time simple skimming the part until it’s made. Who’s got the time for that?
Thanks for the information. Your videos are very informative and succinct (a important trait lost on many youtubers)
First thing I notice is the length of the bit Why so long?
Hi Winston, really enjoying your videos, keep it up!
I've cut aluminum sheets (3mm) with my shapeoko 2 with relative reliable results.
Here is an example of a battery holder for my robot: th-cam.com/video/JGuEo9QiW4s/w-d-xo.html
I usually use a 2 flute, 2mm endmill with my Kress 800 fme-q spindle, speed set to 5 (~28000 rpm if I recall correctly).
DOC 0.2mm, feedrate 600mm, step over 0.4, and width of cut for a profile cut set to 2.5mm (two passes to clear chips more easily). Also using a bit of WD40 to cool the bit.
I lost a couple of bits also, but mostly because of user errors :)
Cheers,
Alex
Thanks!
Why don't you use cutting fluid?
Excellent tutorial, I like the holding tabs, really good idea
Hi sorry for my english. 1 Thing normaly you do not lubricate by cutting aluminium. you have too cool ist for exymple by alkohol. becouse if alu get warm it became smother and clamp your bit
Great video, the machine is over my budget.
use 2 flutes, i would say use a single flute but they are prone to breaking specially the small ones, I have uses 2 flute and abused it on my tiny machine and got away without breaking anything.
Wow, I find that anything faster than 4 inches per minute on a 1/8" end mill results in a broken bit. On a 1/16 inch end mill,2 inches per minute max. This is with a depth of cut of 0.02 inches and an overlap of 30%. Since I went to these speeds I have been able to produce 30 large intricate pieces for a product of mine, without a single broken bit . why the big discrepancy?
+Tom B Spindle speed could be a big factor. I'm cutting at upwards of 20k RPM, and at about half your depth of cut. So it's kind of an inverse relationship, go fast and shallow, or deeper and slower... #twss
YOR VIDEOS ARE GREAT!!
Hi Thanks for sharing.
Be careful when Milling aluminum it shrinks .0005 when it cools, I do 2 finishing passes with a higher rpm with less doc to get a nice surface finish i also just use a compressor with an attached air nozzle to cool my part while cutting.
Not when you cool it enough ;)
I use methylated spirits for cooling and lubrication. But yes, finishing passes are really good to improve the surface finish.
great video!!! very informative... thanks :-)
kerosene or crc works well as a cutting fluid .