3D printing + CNC milling - Worth the effort?
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- เผยแพร่เมื่อ 2 พ.ค. 2024
- 3D printing is accessible, but has its drawbacks. CNC milling for most is harder to set up, butoffers great precision at the cost of inefficient and wasteful subtractive manufacturing. What if we 3D print an oversized model, and then mill it down to the final shape, eliminating layer lines and other imperfections? In this video I experiment with this concept on an F1 in Schools wheel.
I think everything was a win apart from the surface finish. More experimentation with spindle rpm, feed rate and cutting depth could yield better results. Also me having more patience with sanding and polishing at the end would surely help too.
Is this all just a waste of time or are there suitable applications?
0:00 Introduction
0:38 An example of where 3D print plus CNC is needed
Previous F1 in Schools video: • Winning the F1 in Scho...
2:31 The plan
E3D Toolchanger store page: e3d-online.com/products/toolc...
3:21 Sample prints and testing
Previous Apollo X video: • 3D printing functional...
5:15 Model design
6:00 3D printing and machine prep
7:32 CNC milling and toolpath iteration
DeskProto CAM software: www.deskproto.com
CNC toolpath preview: ncviewer.com/
10:17 Evaluating the final parts
12:58 Conclusion
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One of the other advantages of "3D Print then Mill" is that you can print with larger layers and wider nozzle diameters, which increase production speed and part strength. Also, the addition of a coolant spray or water flood to keep the tool and part cool will help with some of the plastics that get grabby when they heat up.
Compressed air works really well with plastic too. Clean and simple.
Good idea! You could also intentionally "squash" your layers to get better layer adhesion. The horizontal expansion doesn't matter if you're intending to mill to dimension.
The layer height is indirect proportional to strength. Smaller layers - - > more strength
@@Taconiteable Look at the results of CNCkitchen for this. He made a whole video of this. It is right to a certain level but not all the way.
Max strenght is just a bit above half of the nozzle-width (so for example .24 or .22 for a .4 nozzle, depending on material and temperatures)
@@Taconiteable It's the ratio of layer width to height that matters. A 1mm layer width and 0.25mm layer height (4:1 ratio) will be stronger than 0.4mm layer width at 0.2mm layer height (2:1 ratio). Strength increases tend to level off above a 4:1 ratio.
Thought this was a 3D printer to CNC mill conversion, but not disappointed one bit! Thank you for your great videos Michael.
In normal 3d use cases the forces on xyz are limited to inertia. I doubt many 3d printers would stand up to the forces of cnc milling. Laser cutting should not be an issue though.
Use a solid rod in the chuck to center parts. Centering on drills/end mills never comes out quite right. And instead of trying to jog the spindle to the part, tighten the clamps to the bed while the part is held centered by the rod. Quick and accurate.
Or you could mount a $20 edge finder……
I use a rod with a 60 degree taper on the end (This works with holes of varying sizes). Use it to force the work against the spoilboard, (or whatever). This centres and holds the work, so you can screw/clamp/glue it according to your preference. The method dates back to hobby lathe work, many years ago... use a centre in the headstock to push the work against a milling slide attachment, then clamp the work. I also used a centre in the tailstock to hold work against a four-jaw chuck, before snugging the chuck jaws up to the workpiece. Equipment moves ever forward, but some of the problems remain the same! :o)
For that specific application, I would ditch the 3d printing altogether and just go with the lathe. Machine it out of POM (Delrin) round stock. That stuff machines very easily, so you'll get an accurate part with a smooth finish. You won't have any of the material waste or heat issues you had with milling acrylic. This addresses all of the points you listed. The only downside is that it requires a bit of manual work, but unless you are mass-producing it's not that much and for students it's a great learning experience.
Agreed - "right materials and tools for the right job". If you just 3D printed a solid rod of material and then machined it on the lathe it would have the same result. Then it is a matter of choosing the right material for the lathe.
Yes, I've been doing this. Works very well and you can get real strong and accurate results.
It might be hard to get it in all colors though which is a positive about 3d printing your base-materials.
I was thinking the same thing watching this. This use case is basically what lathes were born to do.
an alternative way to look at this is that you could use this as a way of recycling your 3D printing waste. Modify a panini press or similar to have a temperature control from a standard PID controller, melt your waste at its lowest plastic temperature (to prevent degrading of the plastic) by heating and folding in the way people recycle PET bottles, then press the molten plastic into moulds CNC milled from wood. Once its cold and you extract the blank, you can mill the part to size from the blank. Probably not suitable for the high tolerance parts you are making, but it would be a great way to reuse your failed prints and prototype parts, since the equipment tor making recycled filament is beyond the reach of most hobbiests. Unfortunately I don't have a CNC or a workshop to try this out, but it might be an idea for a future video?
So glad somebody did a video on this! I've wondered for years about milling thermoplastic.
This is really interesting and coincidentally something I've been thinking about lately! I recently built a beetleweight combat robot out of Billet UHMW and learned a LOT about cutting plastic
A couple thoughts for you to ponder for your application:
-Masking tape and super glue would be ideal work holding here. You've got almost the surface area you need (3 sqin or so) and if you're printing extra to mill away you can probably add a 2mm or 3mm think area to add an extra little bit of surface area if you need. You need the workpiece secured at two points at least to keep it from rotating. Unless it's an engineering plastic you're working with this would be cheap.
-I noticed you're climb milling. I found with UHMW (much more gummy and nylon like than say ASA/ABS) that conventional milling was king. No matter how small a chip load I was trying to run (while remaining a chip still) climb milling was a disaster. As soon as I switched to conventional it milled like butter. The lower cutting force helped tremendously.
Thanks for the video! cool to see it in action!
I use that process for technical model parts.
I use a 0.7mm nozzle, with high extrusion speed and high heat to get good layer adhesion. The optic is not that important. For parts with high stress i cook them in salt to get rid of the layers. I machine them afterwards. I use that process also for lost form casting and then machining. Very useful for parts you have to fit in place. I print and machine the plastic until the result is acceptable and then cast it (aluminum and bronze). The same machining as for the plastic is used to get the exact part i want.
Great video. I use a manual lathe for machining 3D printed parts now but used to regularly machine nylon and other plastics on a VF2 milling machine. Generally, for plastics if you can try increasing your feed rate it is better for getting the cut “over with” and the tool away from the material before it can melt.
Machining from 3D prints is highly effective because you can use more lights-out strategies, save time on complex geometry that would require multiple setups or axis, and so much more. It’s the end game.
I wish i got more time on the millturn with welding additive.... That stuff was awesome
It would be interesting to aneal the wheels and then cnc them. This way you could turn a readily available plastic like petg into a harder, more temperature resistant one. The anealing would compromise dimensional accuracy but then you cnc them to perfection.
I don't think annealing would change the PETG that much. Stefan at CNC Kitchen already did some experiments annealing PLA, PETG, ABS and some high temperature materials. The PETG and ABS had no change in temperature resistance after annealing.
@@Felipeh999 temp resistance perhaps not, but it would probably improve mechanical strength & hardness, which would be more important here
@@Felipeh999 Ah, I missed that video. Thanks for bringing it to my attention :D
Annealing plastics only releases the internal stress created when printing. by evenly heating, then cooling all layers at once you remove the stress.
but the plastic wants to go back to its original shape before it was printed. this means it wants to shrink in the XY direction and grows taller in the Z direction.
Unlike metal where annealing changes the crystalline structure inside the material.
@@awellner3285 it also improves the strength of the bond between the layers- especially correcting any weakened bonds from uneven layer temps during the print
First, this is brilliant and I am going to try this for sure. After 3 years in 3D printing, I've now been using a full size (Onefinity) CNC for the past 6 months and things I can suggest are: 1) 3D print a large block of square material and mill your part out of the middle. Yes there is waste, but when working with both wood and aluminum, I have found it's almost foolproof. This square block also makes setting x-y-z zero very easy using a 3-axis probe or manually. 2) For workpieces that don't allow for traditional clamping, I apply a layer of blue painters tape to the bed and to the underside of the part, then CA (super) glue them together. It holds amazingly well and is extremely easy to remove. 3) I've learned to tell your CNC machine feeds and speeds are correct based on the "chips" produced. You don't want sawdust and you don't want large chunks, but somewhere in the middle. This is because medium size chips actually take a lot of the heat away from both the part and bit as they are being flung off (into the bearings of your machine). 4) In general, the slower your feed, the slower the RPM. And, the larger the bit, the faster your feed. Again, all of this to manage "chipload" (i.e. chips/heat/tool wear). 5) I use Vectric Vcarve software and utilize their "Tabs" feature to prevent parts from flying away when cutting all the way through. You can sometimes skip this step if you use the painters tape trick mentioned as long as there's enough surface contact remaining to counter the torque of milling.
Any advice or recommended resources for someone wanting to move from 3D printing to hobbyist CNC milling?
@@dasgoat76 Here are the channels I've subscribed to that, in order of relevance, should get you started. Please keep in mind that most of this CNC world is based in the realm of wood as the product (and imperial measurements unfortunately), but there are examples out there of people working with everything from aluminum, plastic/acrylic, glass/ceramic, foam, and even concrete/stone. I would say start off using wood and just embrace the fact that you are going to break bits, dust shoes and even clamps as you get used to telling these machines where you want them to move. Good luck!
th-cam.com/users/JamesDeanDesigns
th-cam.com/users/MarkLindsayCNC
th-cam.com/users/IDCWoodcraft
th-cam.com/users/LearnYourCNC
th-cam.com/users/OakHillMillworks
th-cam.com/users/spowerful1250
th-cam.com/users/EigenDesigns
Great information! I had this running through my mind that 3D printing combined with cnc milling could provide results equal to or exceeding casting and milling/machining for making prototypes prior to going into production. Of course my thoughts were involving metals, which I know is now possible to be done with the right equipment.
With Walls Horizontal Expansion 0.2mm I get perfect slip-fit dimensions for 3mm piano wire and 6mm bearings. Very impressed.
I’m glad I’m not the only one thinking about this. I’d like to see how it does making sealed mating surfaces like on an engine or compressor. I’ve been curious about using 3D printing to make small engine parts like cover plates or intake plenums with injection ports for converting carburetor engines.
Time to use my 3018 CNC lathe again!!!
i always thought about a printer that also is a 3 axis cnc but the process of printing and cnc needs to be seperate cuz of hte pressure cnc puts on a printed onto a build plate part. great video. thanks for the food for thought
Great video! ! A few ideas: If you switch to Fusion 360 for CAM, you could use a helical tool path for the outer surface with a tangential exit strategy, it should be smoother. Also, single flute end mills tend to work better for plastics (to keep the chip thick enough with a limites feed rate)
I have succesfully turned functional parts made in eSun PLA+ on my lathe. It cuts surprisingly nice, but doesn't sand well.
I also tried HIPS which machines super well and sands nicely but I didn't have time to dial in the printing for it - irrc I had some warping and layer adhesion issues and even though I did build a simple chamber, I ran out of time so just stuck with PLA+.
My parts were for pneumatic spearguns so they had to hold pressure, tolerances and o-rings had to seal against a smooth surface. Which I could not get straight off of the printer despite it being dialed in super nicely. I did have to make/print some jigs to hold the parts and to counterbalance them. But all in all for my limited parts run (2-3 pieces) this was an OK, educational and fun solution.
I have a resin printer on the way in the hopes that I can skip these secondary machining ops.
As others have mentioned, if you do secondary machining, it also often allows you to print faster and stronger. E.g. I can increase strength and reduce permeability with part cooling fans off, not doing (m)any retractions and printing thicker layers at max temp. But it might lead to a less than perfect surface. Perhaps a price worth paying if you can tidy it up in secondary ops.
(Also, you mentioned acrylic wont work on the CNC. Are you sure, it can't be done...? I mean, I can order CNCed acrylic parts to very good tolerances, which leads me to speculate that you didn't nail the cut parameters. Likely cutting too slow or not with enough engagement).
1) I like your choice of lathe! The Myford Super 7B was their high water mark. :-)
2) For best results always machine 'wet'; i.e. use a spray mist lubrication system and you'll get better finish and no melting.
3) when machining plastic always use new, sharp cutters.
I used petg printed parts on a lathe. This worked perfectly for wheels with ball bearings. A lathe gives a nice finish and everything is centered.
Honestly I'd like to see more of this if it's interesting to you as well. There's a lot of potential for refinement here.
We do this process often with our prototype parts for the drag bikes. We have found that Polymaker PC works the best with all of our testing.
You can mill a flat with the machine itself into the spoil board to make sure the fixture is square to the machine. Using the smooth shank of a worn out endmill flipped upside-down lets you have more reliable surface to align the print from. Roughing down to depth before taking a finishing pass at depth with spring passes completely eliminate any of the bands from the Z steps of the mill. Air blast for plastics is an absolute must.
This is really interesting as I have an E3D Tool Changer and I've built an ASMBL toolhead, but I then read on their site that it's no good with PETG (Which I use for everything) so I never tried it. After seeing your results, I'm going to have to give it a go!
I don't think you mentioned how much you expanded your model by, but you probably want to try to ensure that you'll be milling right through the middle of a layer. (I.e. Expand by 0.5x the line width, or 1.5x, or 2.5x, etc) I think that would give you the best surface finish.
Must say congrats to you and you're students.
Another great video!! I often wondered about the joint use of additive and subtractive techniques. There are situations where using both are applicable. Not sure if this is one of them or if the correct technique was applied. Judging by the very good comments below there are many ways to approach this.
Very Interesting!!!!!
Great video👍
This is part of why I dream of turning a V-Core into a Jubilee. Alas, I have neither the money, nor the skill, nor the time, nor the space for such. Anyway, really cool!
Having been a professional CNC programmer, I can state that these are some ugly tool paths. The cooler tool path options are not available in this type of software though. And tooling choice plays a part in the process as well. Both tool and software that I would recommend are outside of financial feasibility though. A single flute HSS endmill is not super expensive. A 2 flute variable pitch carbide endmill is rather costly. Variable pitch endmills allow for greater cut depth and removes the need to step down.
I haven't looked very closely but I would almost bet that Fusion 360 might have the type of toolpath that would be suitable for excellent results. A spiral cut (no step down) with a lead out (to avoid lifting straight away from the work part and rubbing the entire edge) with a super minimal step over and the use of fluid cooling (water) would be optimal.
Ditto, & agreed. I find hss cutters are generally better than carbide for plastics as long as cooling is up to the task. In this application a flow of compressed air would probably be preferable both for cooling & chip removal. Fusion 360 does indeed have more than adequate tool paths options. It’s the software my present firm uses exclusively for cnc programming (at my recommendation…..)
From my experience machining plastics at work from time to time, you want to cut in the least amount of passes (ideally 1) and to use 1 flute end mills outside the finishing pass. If possible, new mills, sharper, they cut more than drag, reduces heat issues. For the machine I use with ~4mm end mills, I use 12k RPM, with 1000-1200mm/min and it works.
About the screw, mill it in the same direction as the screw threads are in so when forces are applied you don't apply a force that would unscrew the bolt. Most common screws use right handed threads so right hand milling.
As for centering the work, you can first mill a small center hole in your origin, so you know exactly where the center is. Then you attach the part and should be centered by design. Seeing that you require way better precision with good surface finish, I would go buying plastic stock directly once the design is validated with a 3d print and lathe/mill it. It opens more options than just the plastics that are good for 3d printing.
Rails and ball-screws and rigidity is one aspect of accuracy, but runout in the spindle bearing is probably a bigger aspect, ie, the gouged line up the side.
Its nice having both and a laser engraver....and a resin printer. It all works well together. Lets you literally make anything that can be made with the right techniques.
Great video.You have saved me time and effort. When centering holes on a milling machine, I have a rod the same diameter as the cutter I am using that has a 45 deg point. As you lower the point into the hole, adjust the X and Y to get equal space around the hole. The more you lower point the smaller the space and more accurate the position. This method will account for the bump in the wall as the point will touch the bump but the space will be even. Then zero X and Y, change your tool, and Bob’s your uncle. To improve the finish, add a final cut at the minimum depth of cut of the CNC. The roughness is caused by tool chatter and the machine flexing. The lighter the cut the less stress on the machine and vibration. I like the experimentation you do to improve our knowledge. The secret to machining is speeds and feeds and you’ll have to fail before you find the sweet spot.
What end mill are you using?? Great video by the way
I'd be curious to compare that to milling resin printed parts. The nylon like resins seemed to machine really well and I was able to hold a tolerance of .001 inches on printed parts. I was able to thread the parts using a sharp tap as well, so it might be worth looking in to.
Some are saying 'just mill it out of solid plastic' but maybe the biggest advantage here is the reduction of stock variety. I just bought a bar of 50mm delrin because I am prototyping iterations of a 48mm diameter part. Worked fine with minimal waste until a design change means the part now needs to be 52mm diameter!
btw - always a good idea to zero to the spoil board and then add a nominal stock height - gives better finished sizes and allows you to get to the bottom of the part without ever cutting in to the spoil board.
Does the tire surface finish matter much when the vehicle is powered from something like co2 or hpa or something?
With machining of this kind of plastic, depending on the cutter you're using you might get better results with a more agressive helix angle or even a small radius stoned into the corners of the endmil itself (it may address some of the surface tearing).
An interesting aspect to mill an 3dprinted part. In the past I milled things because they were not to print like wood or aluminum. But according to your video I wonder if you would not spend the same time by milling it from a stock material? Also you can choose a less heat sensitive material.
Anyway the milling work in my shop has become rare since autodesk cut more and more functions for the non paying customers. On long term I had to learn cam on freeCad like I done on cad for years successfully.... but that's another story.
I love the concept in using different types of plastics
But really 3d printing is far inexpensive for prototype against cnc of metals
Meaning if you prototype in 3d printing and see the out come then if your happy with the concept
Then one takes it one stage further to cnc in metal.
Thus the cost is far less
No machine cost in wasting time on cnc if one can prove the design via 3d printing
Note one can also print in proper ultrafine metal 3d fililament.
And is a lot quicker begor taking the design project to a commercial cnc metaling machining.
I prefer the the latter.
I prove designers on a 3d printer then go ahead on machining. I save many hours and on tools
That is ideal. A 3D printer may also create the bulk of the part and just the functional surfaces get machined comparatively quickly for the test.
@@Inventorsquare my point exactly
Super slicer have a feature to use a milling cutter.. i guess with additional tool head.. i didn't saw anyone use it
Great video. I'm studying the exact topic of this video in my engineering collage course. I know this is a late message and off topic. I've been using cura, prusa slicer and super slicer, I found that on some models each slicer produced different quality with the exact same print setting's, its why I used all three, BUT as of cura 5.0 all three slicer have removed the PRINT TO USB function from their slicer. From what I can gather a lot of people, myself included, found this feature extremely useful since we only have one printer and print when we need to print. The reasoning for this removal from the devs doesn't make any sense from what I can gather their reasoning is because it was buggy and the devs don't use this feature so the users shouldn't either even though it was very useful to a lot of people and a lot less buggy then the devs made it out. what do you think of this feature being removed.
I find machining reading prints are more dense and rigid the material lines and fused together better
I love experiments
I was thinking about using a lathe to get the tolerances right
great video! but that tool never really gets to cut, it only rubs on the surface, when i machine plastics i programm mostly conventional cuts (because postive tool geometries , like mills made for non ferrous metals tend to "bite" of the corners of the workpiece) but i would still strongly recomment a mill wich has a positive cutting geometry, it generates next to none heat when used correctly. and you maybe wanna try to raise the feedrate significantly, i dont know what your mill is capable of but on "my machine" Hurco VMX 42i i run comparable endmills @ 10000 rpm and 6000-10000 mm/min, with 1-3mm stepdown, if your machine isnt capable of such feedrates try to lower the rpm till you get roundabout 0,05-0,25mm feed per tooth, only conventional cuts, or you will send your piece flying ;D. if the workholding is not strong enough try to lower the stepdown first.
the idea behind this strategy is you wanna be feeding faster than the heat, and move as much heat as possible into the chips, so you always have cool material to machine wich also reduces friction heating by a lot. collant is strictly forbidden, it clogs up the chips, try tool with compressed air instead and if thats not enough consider pure alcohol is an option. i can mail you videos of some programms i wrote if you want some visual context. greetings from austria, not australia:D
I made a very accurate ABS cylinder by 3D printing one slightly oversized with a hex base that I chucked in my CNC lathe and turned to size and then parted it off the base. The surface finish was like it had been polished to a mirror finish.
A lot of people think "ASA is just like ABS," but I've not found that to be true when drilling/sanding (ABS seems superior).
How about taking them to glass temp to fuse them and then coating with epoxy to fill them ? Then mill.
a dial indicator, preferably a coaxial would have been better for locating the part. a 3 jaw chuck would also be better for holding the component in place.
Any reason for not machining with a helical bore toolpath?
I’m curious as to why you went this route instead of just buying a sheet of ABS board, especially since you want the wheel to be solid anyways. Sure, it can be expensive ($60 for a 30x30x2.5 cm board from McMaster Carr), but would be way easier to mill, would take a quarter of the time because you don’t have to worry about 3D printing, and probably costs the same pound for pound as the ABS rolls, and will be stronger due to no layer lines and such. That, on top of not having to fret over making sure your tool alignment is perfect
The combinaison of the 2 technics are really needed when you need accuracy. Thank you Michael!
I feel like perimeters are far weaker than solid infill. I've had some trouble with built in spacers breaking at the layer lines when they're only perimeters.
I always wanted one of these on my doot changer. Got a drill bit but accidentally homed without swtti the offset and killed it after 1 print lol
Maybe one day I can afford to try this
I think without utilizing the benefits of additive manufacturing (parts featuring unmachinable pockets) and more specifically in this application, a solid rod of your chosen material would have served you better. You could order in the correct outer diameter so external machining would not be required and you'd have a nice surface finish already. You could then machine the inside pockets first (center bore, bearing housing, etc). This would allow the pocket wall to be supported by all the outer material; it'd serve to reduce flexing when the endmill engages. You undoubtedly have some flex in the 3D printed part as that wall is only a few mm thick plastic between the bearing/outer pocket. After the bearing area is machined, you could machine the pocket between the wheels internal/external walls since this is a less critical area. I agree with the other commenters on your CAM software. Those paths being generated are making this way more difficult on you; maybe check out Fusion 360 which is free or I think even Solidworks has education packages for $20 or so.
You have more experience so maybe You know the answer. I saw 3 in 1 machines(3d printing, laser engraving, cnc engraving) this cnc module could be used to make some small reliefs? Is it worth buying?
delrin is a machinable plastic that you might try using on the mill.
I wonder if machining one wheel from metal then using it for a urethane mold would be better.
One more layer of process might help with controlling variability and repeatability. I'd be tempted to create one perfected wheel then mold and cast it. It increases materials options and time to reproduce. This way if a wheel is damaged you don't have so many steps to repeat. Powder your silicon mold with graphite before casting and you'll likely have a very low friction wheel. But it does add a variable, it would be fiddly to plan for expected shrinkage of resin during cure.
When you machine any kind of plastic that is vulnerable to heat you need to slow down your cutter and feeds alot. Acrylic does not like fast spindle speed. PET-G is a soft gummy plastic that clogs the cutter flutes causing chip backups and friction thus heating issues on the part.
please give us a review or your thoughts on the Bambu labs Carbon x1 and AMS that's what we all really want from you 😅
Definetly slow the spindle down to about half the rpm you used for that feed rate and stick with the hss end mills over carbide
Some things you need a CNC, like this tungsten/halogen laboratory light source I am building. Tight tolerances, extremely hot temps in the housing. Means no plastic parts, cant use 3D printed metal or lost PLA castings.
This kind of parts (small and revolving) are asking to be resin printed and then machined on the lathe or machined form a solid stock. In 4k resin printed parts there are no naked eye visible layers.
Why did you choose a mill to make round objects instead of a CNC lathe?
Instead of a cutter on the CNC, could we iron the 3d printed part smooth. In fact, why do we need a CNC at all? Could we not have differently shaped heated irons, attached to the 3d printer, and used that to make perfectly smooth 3d printed shapes?
I believe this is something that's being done with titanium in Boeing. Since machining parts is so wasteful for such an expensive material they're printing a rough part with a weld process and then machining down to the finished part
I could easily see the difference sanded and unsanded, also kinda disappointed you didn't do an over-extruded wheel to see if it would machine out perfectly without all of the pits. either way still a great video
Michael do you do any pay phone calls to help with ABL? Maybe 30 min to help get it working. I'll pay before we even start, I'm new at this and can't figure it out. I have an Ender 3 pro with an SKR E3 V3 and a CR touch.
What if you resin printed them?
set your nozzle diameter higher use a 0.4 but set it to 0.5 or .6 this will make wider flat tracks
also in the world on cnc
setting up home switches (i use inductive probes for this)
setup a tool height set point ( mine is a spring loaded steel dowl pin sticking out of my spoil board i have a wire attached to the pin and it checks for contact a simple wingnut under the table compresses the spring so the pin is exactly 0.2500 from the surface using this pin as a datum in all project files with height collars on my tools and a tools preset in my cam software makes it easy to change tools during a job. also i know that Z0 is the surface of the spoil board at any point on the table (i bolt down a 0.5in sheet of MDF and do a surface pass and drill holes counter bores for inserts
Why not just use ABS if you want temperature resistance?
I don't understand why people seem to think ABS is a material that's not actually used anymore. It's far better for functional parts than PLA or PETG.
Have you considered using a resin printer?
Metal 3d printing would make sens. Lets say u have a titanium part. all the waste you have on traditional way and time you waste on roughing it to the shape. A 3d printet part could use less material as a casting or forging so you would safe money on material and a lot of time .
You should try this with some carbon or glass filled nylon. it should allow you to actually print it without warping plus raises the heat deflection temp. I prefer glass bc price and a higher heat deflection temp (friggin 180 degrees celcius). Taulmans GFN is a beast.
Cool, but definitely needs auto calibration for the milling portion.
Also, CNCs definitely need to become smart.
Both probably could be done with strain gauges. Not 100% sure about the calibration, but the smart portion.
If it knows the raw product and the ability of the tool, it could e.g. stop the process /call for help, if it should feel resistance but doesn't.
Or dial back movement rate (when e.g. milling metal) if the strain on the tool comes close to maximum tolerance of the tool. Preventing tool and part damage.
Try to use PETG-CF and add more offset from your zero dimensions at least 0.5mm
👍
Nice video, but you still have a lot to learn about making perfect parts.
I've left some pointers below, good luck.
15mm acrylic could have been cut with CO2 Laser and then you could do the lathe part.
Also, the CNC Milling of acrylic should have been done with a lot of water, slow spindle speed and slow feed rate.
You could also try water jet cutter for acrylic.
7:20 ... Your whole process is wrong.
You should have clamped the Spoil Board to the CNC first.
Then you should have milled a 1mm deep square with a large end mill, now you know that your board or work surface is perpendicular to your Spindle and you also have a good Zero on your Z axis.
Then have the CNC Drill a Hole so that your holding could thread it's way into that hole to hold your part.
I think you need conventional cutting for plastic.
At least for Foam Cutting you have to use Conventional.
And you should have used water.
Spray soap water there like a madman.
I would use a hss mill. Can be sharper than carbide. I don't know how well hss would stand up to carbon.
@Teaching Tech,
You said, "When I was still teaching." I hear that a lot in the U.S. (I'm a teacher there). While I understand the reasons for so many leaving the profession here, I'm curious as to why you left. Are the pressures (and disrespect) faced by Australian teachers as intense as they are here?
Would PEEK or PEKK be good for such an application?
Both are incredibly expensive and brtual to print in the home shop. Marco reps recently managed PEKK with a Qidi X-CF pro that was gcode/firmware modified and had a hell of a time. Pekk is also $600 CAD for 500g.
It absolutley would work but way way out of budget for most things
Really hard to print with a standard 3D Printer.
We have a Intamsys Funmat Pro 410 at work and occasionally print things in PEEK which is not very pleasant to work with, even on a multi thousand dollar industrial printer like this.
It's also not easy to machine, as it tends to warp and crack a lot and requires some machining power. I don't recommend it for a CNC Router, we use real production CNCs (Hermle, Mazak and DMG Mori) and still have problems on some parts.
I'm still blown away that you're old enough to have been a teacher in the past. You barely look like you're old enough to be a student
💕👌👍
When milling plastic I usually use soapy water as a coolant
try POM for the wheel😊
⭐🙂👍
8:21 I ended up laughing, sorry.
Still appreciate the video though. I always wonder what's possible when combining plastic fdm parts with cnc milling.
Maybe I missed it in the video but why 3D print such a simple cylindrical part? Then you used a mill where a lathe would have been way more appropriate and precise. I'm seeing more and more "additive manufacturing bias" all over the 3D printing world. Just because you can 3D print parts doesn't mean you should. In this case if it required plastic parts, you could have acquired some rods of Delrin (a better material) and simply knocked them out on a precise lathe. At least in this case the students got the experience of discovering during development and application that they needed to do something different. That's a good thing.
Wouldn't it just have been easier to mill the wheels from a solid piece of HDPE?
Why not just SLA print?
Check out DMG Mori. They have been building metal 3D printer + 5 axis milling combination machines for a few years now. It's basically a 5 axis milling machine with an added laser welding torch. Mind-blowing to watch.
I am now 2 weeks into trying to get my 3d printer to create something that doesn't suck.
I was close but then I wanted linear advance, uploaded firmware and everything went to shit.
I wanted an easy way to create small helpers, gadgets and jigs... I easily could have made all those out of wood with all the time I've wasted on 3d printing....
I am very close to just chucking the Vyper into a trash can honestly.
No PLA +???
Wrong endmill ... O flute endmills for the win with plastics. Also I would just use POM stock for this I think but ok that was not the purpose of the test.
olso everything round you have to make it on a lathe😊
I saw a Myford lathe. To bad the company went out of business.
Unfortunately having an already thin-wall sort of 3d print that you machined you're forcing an imbalanced wheel. The better idea would be to 3d print a cube 100% infill and then mill a wheel out of it. Why? because in your center homing you're trying to reference an already concentric piece. This is extremely difficult to do on a mill and always results in an imbalanced piece even from microscopic offsets. I have spent countless hours on milling circular objects and getting zeroed dead center (within 1/10,000 of an inch) is crazy hard. Thats why the lathe would have been better. But since you're CNCing this piece you want it to be its own reference and you want the machine to just make its own circular object instead of trying to make an already circular object better.
Wheels should be done on a lathe far better results