In my experience with linear rails**** The manufacturers never use the top of the rail as a reference surface. I think you should be measuring flatness by placing your indicator on top of an installed carriage (ground reference surface) and then moving the carriage down the rail taking reference heights. Also, for matched pairs, the manufacturer usually identifies a master and slave rail and carriages as well as indicates which side of the rails and carriages are reference surfaces. Important to take this into account. You'll find that slave rails sometimes aren't even straight in their un mounted forms. Love your videos, doing amazing things by hand!
Another commenter said a similar thing so I am checking the height variation of the second rail with a micrometer. Not as consistent as I was expecting but then it is not used for the functionality. I’m going to do what you suggested by using the top of an installed carriage as that is what counts. I’ll see what I can include in the next video to show the results. To be honest I checked the top out of curiosity to see if the rail measured any better than the 0.05 mm variation of the top of the epoxy. It might have bridged some of the minor undulations but this rough check suggests it was pretty similar to the epoxy. I’ll have another look at the rails and carraiges for master/slave. Don’t remember seeing anything. Thanks for the comments.
@Andrew MacDonald He is just doing the best he can with the tools he has got. I think its awesome how parallel he got the mounting surfaces just using the epoxy and elbow grease. They are decently flat too.
Ok, I watched Episodes 1 - 17 today. I am a retired Tool & Die Maker and I have to say that I really started drooling at the end of Episode 5. That is some wonderful work. I just subscribed so that I can keep up with the build. My plans are to build a CNC router on a simpler plan, but you have given me several ideas. Thanks!
Hi Curtis. Glad you are enjoying the series and thank you for the kind words. As a hobbiest that means a lot coming from a tool and die maker. Good luck with your project and yes you can make it much simpler than mine.
Hi Curtis, me again. I was thinking about your comments, saying you had just watched the whole series, and the fact that you were a Tool & Die maker. I remember somewhere in the build, around episode 8 & 9 that I needed to make the cover plates. I don't have many tools for sheet metal work and had to improvise. Still, it turned out OK in the end but you must have been smiling at my efforts when you watched that bit ! You will get lots of help on the mycncuk forum (UK based), or you can try the Stateside cnczone forum. Good luck with it.
The goal is to end up with the rails parallel to the base plate, but each is subject to different forces. The leveling liquid responds only to gravity, while the base plate's orientation depends upon its own shape, leveling feet, and frame rigidity. The liquid and base may be perfectly flat - separately - but it's doubtful that they're truly parallel. That said, it always comes down to determining what's good enough and stopping there.
Impressive build and really interesting take on leveling the base for the rails, I'm really curious on how epoxy performed over the many years in service? For example maybe some cracks formed from constant vibration, expansion/contraction etc.
It helps keep the holes centralised. If you are doing this a lot you can heat treat the drill guide to stop it wearing out too quick but I just used mild steel as I only had these two rails to do.
Well done and subscribed. 👍🏼 It amazes me how everyone has there own unique way of building their project, design, outcome and so on, and it whether it’s budget, style, or sheer determination to go over the top its all driving force to a finish line and when it turns out to work as fantastic as it looked through that process that’s not just a job well done it’s a good feeling you’ve accomplished a project with all its complexities and challenges.
Thank you Glenn, those are kind words there. It has been a long journey but with all the thought that went into the upfront design it all went together as planned in the end. Been using it for a while now building the electric go-kart for my daughter (see other video) and it has not missed a beat. Very pleased, thanks.
Just found your channel and I am really impressed with your attention to detail. I think I will be binge watching the entire build process so fat a bit later. This is going o be an awsome machine once it is finished and properly tuned.
Thank you. If you start at the beginning you will probably see the video quality improve too! I’m also looking forward to getting it running after 2 years of design and build.
OK - Binge watch over... And I am astounded at your expertise and attention to detail !!! Just one concern but you probably already have it covered and that is your spindle. I hope it is water cooled because we all know how reactive ally is to temperature differences as far as dimensional stability is concerned. And one has to wonder just how many man-hours have gone into this project... It is a fantastic build and will probably become the benchmark for people wanting to really do a decent job of it - you have set the bar real high.
Thank you for those kind words. I’ve been doing this a few years and this is MK4 so contains all the learning from the previous builds plus new ideas I’ve developed or seen on other machines. I’m hoping it’s the last at least for a few years and I can start using it. I wouldn’t like to count the man hours but it started about 2 years ago with the design work and now it is starting to come together at last. Yes the spindle is water cooled. It barely runs warm to the touch and I often don’t run the pump for small jobs. It is a Chinese 1.5kW spindle but if you are thinking of a build then go for 2.2 kW as the dimensions are the same but it has more power and you can go up to 12 mm or so in the collet. I’m limited to about 6mm due to the collet size.
You can get .0002" paper shims (it's called onion shim, you can find it on eBay) or .0005" stainless shims to get it more straight. I am building a machine with 300mm Y and 400mm Z travel and each axis only took me a couple hours. Also, vibrating the machine when it's setting might help if you plan on building a new one.
The reason the surfaces aren't absolutely perfect but follow the original topology is probably shrinkage. Where the resin was thicker the amount of shrinkage was proportionally higher as well. For a single layer of resin the result looks very good. I would've tried to shave off a couple micron with a fine wetstone, but that's just my ocd kicking in. For the usual 2.5D operations a deviation in Z of less than a tenth is acceptable in my book. If it has to be even more precise, one could always probe the workpiece before milling a crutial feature. Keep it up. I'm exited to see all the pieces come together. Btw I know you can "map" the pitch deviation of the spindles in Mach3/4 ... maybe there's a feature that lets you do the same for hight profiles of the guides. Or someone in the forums made an add-on.
I think you could be right on the shrinkage which is why to try to limit that I put the cross channels right out at the ends not 2 runs across the middle like some others have done to minimise any changes in section or direction happening on the main straights. Others on my regular mycncuk have suggested a multi-layer approach why multiple thin layers are put down just waiting for the previous layer to set but still be tacky to create a bond. The idea being if the surface underneath is being telegraphed to the top surface to a degree this would eventually even out with each new layer. No evidence this would work and may end up with shrinkage (if that is the main cause) dominating the final result anyway. The other thing to bare in mind with all this is that my reference plate is a piece of fairly flat marble, that I trust over most of the surface to be good to 0.05 mm. I've compared it to other small known flat items and it checks out to at least this, plus if I put a ground angle plate onto it and pick it up there is an amount of suction that occurs as if the ground block and the marble plate have started to ring together like gauge blocks. However, it is not a calibrated plate and below 0.05 mm I can't really be sure so any chasing to get to 0.01 mm would really be guessing and could actually be making it worse. If I had a calibrated granite plate that was long enough I would definitely try to stone it down and/or shim down to 0.01 mm. But they are not cheap! On the screw mapping yes I'd seen that but never needed to use it. The Z mapping is an interesting idea - seems to ring a bell for guys doing PCB boards where they can probe the surface and get the actual heights as they need to control the track cut away reasonably precisely. Although to be honest this is pretty good as it is and I will go with what I have. Great comments thank you.
Nice build. A lot of care and attention here. A pleasure to watch. I wouldn’t trust that marble or granite piece of bench top but better that’s nothing. Well done and I look forward to seeing more.
Why dont buy a straight granite. It is not expensive for chinese made one. I got a piece together with a triangular and a 400x500 granite platform. The platform is not large enough. I took a scraped tilte but dont know how flat it is.
Still huge improvement. You don't want the sides of your trench to be 90 degrees because of the meniscus curving up. V sides that match viscosity get a flat surface. Also heating the pour surface for better flow and degassing the epoxy with a vacuum gets better results since gas in the epoxy expands as it cures creating uneven surfaces. Your carriage might not be sliding level either. For best results use a laser pointer on a sliding block on a distant wall. draw a dot and if the laser stays on the dot it is level. The further away the wall the greater the accuracy. You can get crazy accurate because just like a rifle a tiny movement of the laser translates to a huge movement on the wall.
I made the epoxy wide enough so the rails sat in the middle. So didn’t need to worry about the miniscus. I did look into vacuuming the epoxy but the kit to do it was fairly expensive and would only be used once. My experience with heating the epoxy to remove bubbles is you can only do it briefly otherwise it brings on the curing rapidly ! Good idea with the laser pointer I could have done that as another check. Thanks
@@routercnc9517 Yea I noticed the width. You can use an old fridge compressor and a big bucket to degas epoxy. You don't need a really strong vacuum. How is the CNC doing now that you have had it for a while? Such an amazing build. Do you know how much you spent?
I’ve been very good pleased with it and have made lots of things to support various projects. An electric kart conversion for my daughter (see series on my channel if interested) and my drill press conversion (current video series). They only thing I could do with is a compressor and mist to cut faster. But accuracy is very good. Cost is hard because I’ve reused parts from older machines and this is the 4th major development but it must be in the £3000 region ($5000?). I try not to add it up !
@@routercnc9517 Wow that is less than I expected. A $5 aquarium pump and some garden misters from the hardware store would be a cheap solution but aliexpress has plenty of cheap options for that. I am guessing the liquid removal is more your problem.
Yes the costs to build from scratch would be higher but I was able to use most of the mechanical parts from the previous build and the spindle. So it was the aluminium, accessories and bits and pieces which all add up ! I really want fog buster style Not flood as can’t contain the liquid. Compressor is on the list . . . one day!
I saw another TH-cam vid where it was suggested that the rails themselves might not be evenly flat to the micron? Perhaps check rail thickness along the length (optionally plus a little hand grinding...) Technique seemed to be to put carriage in vice, then run rail through it and indicate along length
I hadn’t thought about that and yes the top surface looks ground but maybe not as accurate as I was assuming. I was going to put the carraiges on next so will repeat the flatness test but indicate to the top surface of the carriage - in the end that is what matters as the gantry sits on there. Good shout thanks.
Actually I think it will be the bottom surface you grind? Think about clamping the carriage in the vice so that's your absolute zero. Then add you run the rail through you will be observing the effective error being added to your frame surface. You might even find it explains much of your observed rail error right now? I wonder even if the top of the rail is a great proxy for the plane of the carriage on the rail??
Makes sense. What I meant was that I had referenced to the top of the rail for my final test. Your method makes a lot of sense though as I don’t need a surface plate. Not sure I’d be brave enough to grind any ‘error’ away. I’ll do some checks on the second rail as I haven’t fitted that yet. I could also mic up the rail at different points to see the variation. The more I think about it the more rail / rail carraige tests need to be looked at. Keep them coming and if it looks interesting I may put them in the next video.
I was tempted but I don’t trust the marble reference plate to be flat enough to go any further. I’m going to settle at that for the vertical flatness. I’ll be checking the lateral straightness along the rail length next.
It was an old marble hearth surround. I checked it against known flat/ground surfaces and it is fairly flat. I can also put ground plates on top of it and when I lift them up there is a suction effect and it starts to lift the marble plate, which is another check how flat it is. I trust it to at least 0.05 mm, but not sure below that. When funds allow a proper granite plate would be great but they are expensive in that size. Thanks.
How do you ensure parallelism between rails? For it to be accurate. How do you ensure perpendicularity with the gantry? How do you measure the exact distance between the left and right rails, since I do not know of a comparison instrument to measure the parallelism between the two rails. I work, assembled machines with the same structure, only they have, a tank between the rails. My problem has been aligning the rails on each side, to ensure parallelism and squareness. The rails are located at a distance of 3 meters from each other. Do you know any technical and effective alignment system. Well, I do it empirically with a tensioned steel wire.
The first rail is fitted roughly. Then the opposite rail is fitted and a long bar attached to a carriage on the first rail is fitted with a DTI touching the opposite rail carriage. Then the first carriage and DTI is swept along the other rail and the second rail adjusted until it is parallel. For squaring to the gantry this is done later. The gantry is aligned to be square to the X rails. See later in the video series. Thanks
Your thread guide and drill guide should have has a slot cut in the bottom so they would overhang the rail sides and not rotate. If you were going to clamp them you should have used a fork clamp rather than a toe clamp. How do you know your reference surface that the indicator is sliding on is flat or level?
The thread guide mod you suggest would have made it easier. Maybe next time ! The reference surface is flat to at least 0.05mm and typically better along the surface, as tested by reference to other known precision ground items. It is not a surface plate but is all I have. In terms of level I shimmed under the reference surface until the DTI reading deviation was a minimum from end to end as all I wanted to know at this stage was the peak to peak error along the length. I really wanted to see how much flatter this made the surface compared to the bare steel underneath and the answer was quite a bit. Thanks
sorry i'm not trained in tapping, but arn't you suppost to give it a 1/4-1/2 backtwist every 1 or 2 full turns to cut off the material so it doesn't block later on?
Some styles of taps are like that but these are spiral fluted taps which pull the material out behind them so you don't need to break the chip. Of course if you feel the tap starting to jam then you should stop and retract it to clean it but otherwise you can keep going.
Thanks Gavin. I’ve thought about narration but at the moment my video style is mainly documenting my progress with a bit of music and editing to stop it being too boring.
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Another very good one Congrats for the 1000 subs 👍
Cheers Clive. I hope you enjoyed the ToT segment - that guy is a legend ! It was nice to finally put some numbers to the epoxy method. I was very tempted to shim in the last bit but what stopped me in the end was: 1) 0.05 is not too bad, 2) I want to finish this thing, 3) the marble reference bed is probably not flat enough to go any further. I will check the lateral rail straightness in the next video as they are just roughed in for now, but the vertical flatness on the first rail is good to go. Thanks.
Many others on the mycncuk forum have used epoxy this way and had no issues. I think the forces are spread over a large area so the stress is not too high. I would have liked to machined the steel box flat but don’t have anything that large to do it.
May I ask what the dimensions of the extrusions your using in this build? Are they steel or aluminum extrusions? I know the top square tubes are steel.
They are heavy gauge aluminium profiles 80x80 mm. Someone gave them to me many years ago as they were well used and beat up in places. I cut out the good bits and cleaned them up. Thanks
Agreed but I only have that marble plate. I trust it to 0.05 mm flatness based on using it to measure known ground flat objects, but no more. A proper surface plate is on my wish list. Thanks
I had a few goes to get it right. I put my cross channels off the edge of the machine so any shrinkage around the corner would not affect the main rail area. Also I used very slow set epoxy. I’m no epoxy expert but that worked for me.
Yes the rails are Hiwin HGR20 and are 1150mm long. Carriages are HGH20HA. You can also get slightly shorter carriages (HGH20CA), or flanged mounted (HGW20HA/CA). They were from BST Automation on AliExpress. Thanks.
Actually I’ve ordered lots of stuff from Fred at BST as have most of the mycncuk forum. Been reliable for years, any issues are sorted, quality and price is good.
Do you mean 0.2 mm, the error on the raw box section? If so for a router doing wood work this might be just about acceptable, but for machining metal parts (which is also what I need to do) this is far too much. With the epoxy leveling I am now at about 0.05 mm of variation in rail height (using the tools I have to hand) which is OK for a home build. Thanks.
I don’t understand how it is possible to calibrate a plane according to some piece of plastic (?) on which the indicator stand is based, because it must move along a very even reference plane? Even if you put the calibration plate, it will stand on the uneven surface of the aluminum profile and in the end you measure the deviation from the plane of the non-curved profile P.s. possible translation errors google translator, greetings from mother Russia))
It was a piece a granite plate which is quite thick, stiff and fairly flat. I trust it to about 0.05 mm but no more. I shimmed it away from the aluminium until the deviation was minimised just to make the maths easier. Don’t forget I did a best fit line and subtracted this because I only want to know the deviation from straight. Then later I checked that the other rail was in the same plane. Hope this makes sense. Greetings from the UK !
I thought the whole point of the epoxy was to assure the rails were level. Running an indicator across the top tells you that the base is not parallel with the rails, but you need to shim the base to fix it, not the rails. I hope you have not worked yourself into a corner with that epoxy fiasco. I think you should have stuck to building a machine that was straight and parallel to itself then leveled the table, rather than throw the parallelism out the window for the sake of leveling the rails. And if you are just going to shim the rails to bring them parallel to the base, what was the point of the epoxy at all?
I’m not doing what you think I’m doing. Yes the epoxy was to get the rails level in space but I wanted to know how flat they were (ie local undulations). The indicator was used to measure the flatness of the rails not how parallel they are to the base. The reference plate was placed on the base for convenience and shimmed to get the minimum net movement on the DTI so it would just measure the residual flatness of the rails. I’m not interested in the base itself at this point. You don’t have to shim it to take this measurement but then you need to subtract a best fit line. When complete the base will then be machined parallel to the rails by the machine itself so it will all work out. Thanks.
Agree but those were to tools I had. At least I was only getting an idea of the flatness. If I was shimming it in then I would need to do something better. Thanks
I have just bought a precision level to check the absolute level and across to the other rail. You should see it in the next video. Thanks for your comment.
Here is the google translation from Lucy for anyone interested: "precision level. You have to center it, you have no choice, the machine needs absolute horizontal & vertical, you do not know exactly what, where this is based on this method,"
Hi Jason. Thanks for the feedback. I’m still learning on the video creation side and hopefully the later ones are better (up to episode 23 now) but I will keep on trying to improve them. Thanks
Good idea! But, the question is how flat the surface is? Only liquids have flat and horizontal surface. Semi fluids like epoxy... I am not sure. But, there it is like it is... Another thing: too much job and effort and too complicated specially because you made two special supporting tools, too many clamping... Little advice: if it is possible always avoid to do the things on site (cutting, drilling, taping etc). Thinking and planning ahead with the precise work gave the result. Look, just milling the top and bottom surfaces of the supporting tube on one good and precise machine to make them flat and parallel is good enough. Also, drilling the holes for the screws on that same machine is more easier, wright? Also, drilling little bigger holes saves time (ex. for HIWIN HGH20CA rail the screw is M5. You can safely drill 6mm or even 7mm hole into the epoxy+tube to allow the space for the adjustment). To fix the guides you had a far better solution. Look at my solution which is tested many, many times. Video link: th-cam.com/video/YpnX0DQygW0/w-d-xo.html. The steel bar with the tapped holes will do the better job. The bound between the rail and the supporting epoxy+tube is very strong because you have more than enough depth for the thread in the bar unlike in the relatively thin wall of the supporting tube. So, you can tight them strongly. The holes are easier to drill and tap on the bar because you do not have to do it on site but away on some machine. At last, all is easy to mount and easy to adjust the rails.
You are right with those points but I had to do it this way because of a few reasons. I don't have a milling machine so have no way of machining the sections flat, especially at that length. So I thought I would try the epoxy method and measure the results. Flatness to within 0.05 mm is pretty good for a DIY machine made in my garage. Also the original design had supported round rail and I had drilled and tapped the holes for that using the CNC mk3. But during this build I decided to buy the linear profile rails, and the holes are in the centre, not the edges, and because the mk3 machine was in pieces I had to drill and tap by hand. I made the drill guides to make this easier, and really quite enjoyed that part. This is just a hobby for me. On my gantry I did use a reinforcement plate under the rails (as per your method) to make the section much thicker, but on the bed the wall was already 5-6mm which is quite a lot for tapping so just went direct into that. Now I've done one machine with epoxy I would have to seriously think about whether to do it this way again. Maybe pay someone to machine the longer RHS sections that the rails sit on would end up being better overall. Still, glad I've got this far and can share what I learn with others. Thanks for your comments.
Thank you! Yes, I understand. I am DIY man too. My opinion is that this is very, very serious and very strong machine! So to spend few bucks more for the machining is worth. But I forgot to tell you: I really enjoy your work and I am waiting for the next video. Go! Go! Go!
Thanks Pecilije, very encouraging! I'm working on the next video, which should include even more measurements of the rails etc. (using the tools I have to hand), and a bit more progress but not ready yet. I can only get into the workshop at the weekend and usually only an hour or so.
Sorry about that. I just watched it back again and yes it was a bit strong near the beginning. I’ll try to calm it down on the next one so it is less distracting. Thanks
When I saw you building a surface out of epoxy to make a flat surface I thought this guy is just trying to sell epoxy like so many weirdos on the youtube, but when I saw you using a banggood mic I knew you were a shill.
Unfortunately I had to buy the epoxy and it was not cheap. No affiliation or anything there.. If you have access to a large mill that would be quicker and cheaper to level the surface. Epoxy levelling is a popular method on the mycncuk forum, but there are not many videos showing it being used so I thought I would show my first experiences with it. West is a popular choice so I went with that but there are several other brands available. The banggood mic was a free trial item I was sent and in return just had to put links in the description text box. No kick backs, and not in it for that just want to show my progress and share design ideas with others. Thanks.
Why is it that pricks like you can only crap on a guys effort to share his build experience, Some of us hobbyist machinists can only afford Banggood quality gauges and such but dream of starrett. We use what we can afford but at least we're doing something. When you get off your ass and share something besides criticism, maybe someone will watch, until then don't share your worthless opinions. Maybe a flapping gums video would be a hit?
In my experience with linear rails**** The manufacturers never use the top of the rail as a reference surface. I think you should be measuring flatness by placing your indicator on top of an installed carriage (ground reference surface) and then moving the carriage down the rail taking reference heights.
Also, for matched pairs, the manufacturer usually identifies a master and slave rail and carriages as well as indicates which side of the rails and carriages are reference surfaces.
Important to take this into account. You'll find that slave rails sometimes aren't even straight in their un mounted forms.
Love your videos, doing amazing things by hand!
Another commenter said a similar thing so I am checking the height variation of the second rail with a micrometer. Not as consistent as I was expecting but then it is not used for the functionality. I’m going to do what you suggested by using the top of an installed carriage as that is what counts.
I’ll see what I can include in the next video to show the results.
To be honest I checked the top out of curiosity to see if the rail measured any better than the 0.05 mm variation of the top of the epoxy. It might have bridged some of the minor undulations but this rough check suggests it was pretty similar to the epoxy.
I’ll have another look at the rails and carraiges for master/slave. Don’t remember seeing anything. Thanks for the comments.
@Andrew MacDonald He is just doing the best he can with the tools he has got. I think its awesome how parallel he got the mounting surfaces just using the epoxy and elbow grease. They are decently flat too.
Ok, I watched Episodes 1 - 17 today. I am a retired Tool & Die Maker and I have to say that I really started drooling at the end of Episode 5. That is some wonderful work. I just subscribed so that I can keep up with the build. My plans are to build a CNC router on a simpler plan, but you have given me several ideas. Thanks!
Hi Curtis. Glad you are enjoying the series and thank you for the kind words. As a hobbiest that means a lot coming from a tool and die maker. Good luck with your project and yes you can make it much simpler than mine.
Hi Curtis, me again. I was thinking about your comments, saying you had just watched the whole series, and the fact that you were a Tool & Die maker. I remember somewhere in the build, around episode 8 & 9 that I needed to make the cover plates. I don't have many tools for sheet metal work and had to improvise. Still, it turned out OK in the end but you must have been smiling at my efforts when you watched that bit !
You will get lots of help on the mycncuk forum (UK based), or you can try the Stateside cnczone forum. Good luck with it.
Been here only for a few days but everytime I hear that music my tail starts wiggling.
Glad you are enjoying the show ! 🐕🦺
The goal is to end up with the rails parallel to the base plate, but each is subject to different forces. The leveling liquid responds only to gravity, while the base plate's orientation depends upon its own shape, leveling feet, and frame rigidity. The liquid and base may be perfectly flat - separately - but it's doubtful that they're truly parallel. That said, it always comes down to determining what's good enough and stopping there.
Yes you need to skim machine the bed using the spindle once everything is together to get them somewhat parallel. Thanks
Impressive build and really interesting take on leveling the base for the rails, I'm really curious on how epoxy performed over the many years in service? For example maybe some cracks formed from constant vibration, expansion/contraction etc.
It’s been great. No problems or cracking.
Sweet, gonna try it on my future build! Thank you :)
I like the Bushing Idea I saw that somewhere else Definitely going to use that.
It helps keep the holes centralised. If you are doing this a lot you can heat treat the drill guide to stop it wearing out too quick but I just used mild steel as I only had these two rails to do.
good idea indeed
Well done and subscribed. 👍🏼
It amazes me how everyone has there own unique way of building their project, design, outcome and so on, and it whether it’s budget, style, or sheer determination to go over the top its all driving force to a finish line and when it turns out to work as fantastic as it looked through that process that’s not just a job well done it’s a good feeling you’ve accomplished a project with all its complexities and challenges.
Thank you Glenn, those are kind words there. It has been a long journey but with all the thought that went into the upfront design it all went together as planned in the end. Been using it for a while now building the electric go-kart for my daughter (see other video) and it has not missed a beat. Very pleased, thanks.
Just found your channel and I am really impressed with your attention to detail.
I think I will be binge watching the entire build process so fat a bit later.
This is going o be an awsome machine once it is finished and properly tuned.
Thank you. If you start at the beginning you will probably see the video quality improve too! I’m also looking forward to getting it running after 2 years of design and build.
OK - Binge watch over... And I am astounded at your expertise and attention to detail !!!
Just one concern but you probably already have it covered and that is your spindle.
I hope it is water cooled because we all know how reactive ally is to temperature differences as far as dimensional stability is concerned.
And one has to wonder just how many man-hours have gone into this project...
It is a fantastic build and will probably become the benchmark for people wanting to really do a decent job of it - you have set the bar real high.
Thank you for those kind words. I’ve been doing this a few years and this is MK4 so contains all the learning from the previous builds plus new ideas I’ve developed or seen on other machines. I’m hoping it’s the last at least for a few years and I can start using it. I wouldn’t like to count the man hours but it started about 2 years ago with the design work and now it is starting to come together at last. Yes the spindle is water cooled. It barely runs warm to the touch and I often don’t run the pump for small jobs. It is a Chinese 1.5kW spindle but if you are thinking of a build then go for 2.2 kW as the dimensions are the same but it has more power and you can go up to 12 mm or so in the collet. I’m limited to about 6mm due to the collet size.
facing some similar problems this is some good information, thanks + subscribed!
Ok great. Thanks for following along!
You can get .0002" paper shims (it's called onion shim, you can find it on eBay) or .0005" stainless shims to get it more straight. I am building a machine with 300mm Y and 400mm Z travel and each axis only took me a couple hours. Also, vibrating the machine when it's setting might help if you plan on building a new one.
Yes I could have shimmed it further but the granite reference surface is not calibrated and may not be more than 0.05 mm flat everywhere.
The reason the surfaces aren't absolutely perfect but follow the original topology is probably shrinkage. Where the resin was thicker the amount of shrinkage was proportionally higher as well. For a single layer of resin the result looks very good. I would've tried to shave off a couple micron with a fine wetstone, but that's just my ocd kicking in. For the usual 2.5D operations a deviation in Z of less than a tenth is acceptable in my book. If it has to be even more precise, one could always probe the workpiece before milling a crutial feature.
Keep it up. I'm exited to see all the pieces come together.
Btw I know you can "map" the pitch deviation of the spindles in Mach3/4 ... maybe there's a feature that lets you do the same for hight profiles of the guides. Or someone in the forums made an add-on.
I think you could be right on the shrinkage which is why to try to limit that I put the cross channels right out at the ends not 2 runs across the middle like some others have done to minimise any changes in section or direction happening on the main straights.
Others on my regular mycncuk have suggested a multi-layer approach why multiple thin layers are put down just waiting for the previous layer to set but still be tacky to create a bond. The idea being if the surface underneath is being telegraphed to the top surface to a degree this would eventually even out with each new layer. No evidence this would work and may end up with shrinkage (if that is the main cause) dominating the final result anyway.
The other thing to bare in mind with all this is that my reference plate is a piece of fairly flat marble, that I trust over most of the surface to be good to 0.05 mm. I've compared it to other small known flat items and it checks out to at least this, plus if I put a ground angle plate onto it and pick it up there is an amount of suction that occurs as if the ground block and the marble plate have started to ring together like gauge blocks.
However, it is not a calibrated plate and below 0.05 mm I can't really be sure so any chasing to get to 0.01 mm would really be guessing and could actually be making it worse. If I had a calibrated granite plate that was long enough I would definitely try to stone it down and/or shim down to 0.01 mm. But they are not cheap!
On the screw mapping yes I'd seen that but never needed to use it. The Z mapping is an interesting idea - seems to ring a bell for guys doing PCB boards where they can probe the surface and get the actual heights as they need to control the track cut away reasonably precisely. Although to be honest this is pretty good as it is and I will go with what I have.
Great comments thank you.
Nice build. A lot of care and attention here. A pleasure to watch. I wouldn’t trust that marble or granite piece of bench top but better that’s nothing. Well done and I look forward to seeing more.
Thanks.
Why dont buy a straight granite. It is not expensive for chinese made one. I got a piece together with a triangular and a 400x500 granite platform. The platform is not large enough. I took a scraped tilte but dont know how flat it is.
It’s certainly on my wish list but last time I looked at something like that it was quite expensive. I’ll have another look thanks
Still huge improvement. You don't want the sides of your trench to be 90 degrees because of the meniscus curving up. V sides that match viscosity get a flat surface. Also heating the pour surface for better flow and degassing the epoxy with a vacuum gets better results since gas in the epoxy expands as it cures creating uneven surfaces. Your carriage might not be sliding level either. For best results use a laser pointer on a sliding block on a distant wall. draw a dot and if the laser stays on the dot it is level. The further away the wall the greater the accuracy. You can get crazy accurate because just like a rifle a tiny movement of the laser translates to a huge movement on the wall.
I made the epoxy wide enough so the rails sat in the middle. So didn’t need to worry about the miniscus. I did look into vacuuming the epoxy but the kit to do it was fairly expensive and would only be used once. My experience with heating the epoxy to remove bubbles is you can only do it briefly otherwise it brings on the curing rapidly ! Good idea with the laser pointer I could have done that as another check. Thanks
@@routercnc9517 Yea I noticed the width. You can use an old fridge compressor and a big bucket to degas epoxy. You don't need a really strong vacuum. How is the CNC doing now that you have had it for a while? Such an amazing build. Do you know how much you spent?
I’ve been very good pleased with it and have made lots of things to support various projects. An electric kart conversion for my daughter (see series on my channel if interested) and my drill press conversion (current video series). They only thing I could do with is a compressor and mist to cut faster. But accuracy is very good. Cost is hard because I’ve reused parts from older
machines and this is the 4th major development but it must be in the £3000 region ($5000?). I try not to add it up !
@@routercnc9517 Wow that is less than I expected. A $5 aquarium pump and some garden misters from the hardware store would be a cheap solution but aliexpress has plenty of cheap options for that. I am guessing the liquid removal is more your problem.
Yes the costs to build from scratch would be higher but I was able to use most of the mechanical parts from the previous build and the spindle. So it was the aluminium, accessories and bits and pieces which all add up !
I really want fog buster style Not flood as can’t contain the liquid. Compressor is on the list . . . one day!
Subscribed just for the Old Tony tribute :D
Thanks. He is my hero !
I saw another TH-cam vid where it was suggested that the rails themselves might not be evenly flat to the micron? Perhaps check rail thickness along the length (optionally plus a little hand grinding...)
Technique seemed to be to put carriage in vice, then run rail through it and indicate along length
I hadn’t thought about that and yes the top surface looks ground but maybe not as accurate as I was assuming. I was going to put the carraiges on next so will repeat the flatness test but indicate to the top surface of the carriage - in the end that is what matters as the gantry sits on there. Good shout thanks.
Actually I think it will be the bottom surface you grind? Think about clamping the carriage in the vice so that's your absolute zero. Then add you run the rail through you will be observing the effective error being added to your frame surface. You might even find it explains much of your observed rail error right now? I wonder even if the top of the rail is a great proxy for the plane of the carriage on the rail??
Makes sense. What I meant was that I had referenced to the top of the rail for my final test. Your method makes a lot of sense though as I don’t need a surface plate. Not sure I’d be brave enough to grind any ‘error’ away. I’ll do some checks on the second rail as I haven’t fitted that yet. I could also mic up the rail at different points to see the variation. The more I think about it the more rail / rail carraige tests need to be looked at. Keep them coming and if it looks interesting I may put them in the next video.
Are you gonna put shim under the rail where needed in order to level it even better?
I was tempted but I don’t trust the marble reference plate to be flat enough to go any further. I’m going to settle at that for the vertical flatness. I’ll be checking the lateral straightness along the rail length next.
What is the surface on which you were sliding your angle base across? Was it precision ground granite?
It was an old marble hearth surround. I checked it against known flat/ground surfaces and it is fairly flat. I can also put ground plates on top of it and when I lift them up there is a suction effect and it starts to lift the marble plate, which is another check how flat it is. I trust it to at least 0.05 mm, but not sure below that. When funds allow a proper granite plate would be great but they are expensive in that size. Thanks.
I’m so excited to watch this!
Hi Matt
Glad you are enjoying the videos!
routercnc it’s inspiring, keep up the good work!!!
Thanks. Makes the efforts worthwhile.
How do you ensure parallelism between rails? For it to be accurate. How do you ensure perpendicularity with the gantry?
How do you measure the exact distance between the left and right rails, since I do not know of a comparison instrument to measure the parallelism between the two rails.
I work, assembled machines with the same structure, only they have, a tank between the rails. My problem has been aligning the rails on each side, to ensure parallelism and squareness. The rails are located at a distance of 3 meters from each other. Do you know any technical and effective alignment system. Well, I do it empirically with a tensioned steel wire.
The first rail is fitted roughly. Then the opposite rail is fitted and a long bar attached to a carriage on the first rail is fitted with a DTI touching the opposite rail carriage. Then the first carriage and DTI is swept along the other rail and the second rail adjusted until it is parallel. For squaring to the gantry this is done later. The gantry is aligned to be square to the X rails. See later in the video series. Thanks
Your thread guide and drill guide should have has a slot cut in the bottom so they would overhang the rail sides and not rotate. If you were going to clamp them you should have used a fork clamp rather than a toe clamp. How do you know your reference surface that the indicator is sliding on is flat or level?
The thread guide mod you suggest would have made it easier. Maybe next time !
The reference surface is flat to at least 0.05mm and typically better along the surface, as tested by reference to other known precision ground items. It is not a surface plate but is all I have.
In terms of level I shimmed under the reference surface until the DTI reading deviation was a minimum from end to end as all I wanted to know at this stage was the peak to peak error along the length. I really wanted to see how much flatter this made the surface compared to the bare steel underneath and the answer was quite a bit. Thanks
sorry i'm not trained in tapping, but arn't you suppost to give it a 1/4-1/2 backtwist every 1 or 2 full turns to cut off the material so it doesn't block later on?
Some styles of taps are like that but these are spiral fluted taps which pull the material out behind them so you don't need to break the chip. Of course if you feel the tap starting to jam then you should stop and retract it to clean it but otherwise you can keep going.
Nice vid a bit of narration would be nice but looks like it’s gonna be a great cnc
Thanks Gavin. I’ve thought about narration but at the moment my video style is mainly documenting my progress with a bit of music and editing to stop it being too boring.
Another very good one
Congrats for the 1000 subs 👍
Thanks Jeremie
Nice vid as always.
Cheers Clive. I hope you enjoyed the ToT segment - that guy is a legend !
It was nice to finally put some numbers to the epoxy method. I was very tempted to shim in the last bit but what stopped me in the end was: 1) 0.05 is not too bad, 2) I want to finish this thing, 3) the marble reference bed is probably not flat enough to go any further.
I will check the lateral rail straightness in the next video as they are just roughed in for now, but the vertical flatness on the first rail is good to go.
Thanks.
Is the epoxy enough firm to support pressure caused by milling? I'm afraid that it will be deformed by the pressure..
Many others on the mycncuk forum have used epoxy this way and had no issues. I think the forces are spread over a large area so the stress is not too high. I would have liked to machined the steel box flat but don’t have anything that large to do it.
May I ask what the dimensions of the extrusions your using in this build? Are they steel or aluminum extrusions? I know the top square tubes are steel.
They are heavy gauge aluminium profiles 80x80 mm. Someone gave them to me many years ago as they were well used and beat up in places. I cut out the good bits and cleaned them up. Thanks
@@routercnc9517 wow, what a good gift haha. And I've learned a lot from your videos, I appreciate your efforts in recording!
your indicator has to be on a granite or ground plate, I do field service and use a 35lb certified granite
Agreed but I only have that marble plate. I trust it to 0.05 mm flatness based on using it to measure known ground flat objects, but no more. A proper surface plate is on my wish list. Thanks
Did you account for the curvature of the earth when you were pouring epoxy? :D Great work
As the lengths of the rails were only 0.0000094176 % the diameter of the Earth I figured it would be OK :)
But hang on isn't the Earth Flat?
It is in my workshop - not sure about the rest of it . . .
Has anyone else made the epoxy system?
Yes, plenty on the mycncuk forum. Usually takes people 1 or 2 attempts to get to know how to handle it (as I also found out!).
@@routercnc9517I spilled 3 times but their faces were always crooked
I poured epoxy on my machine, but the result was a big disappointment, but I could not understand the reason, it was completely wavy.
I had a few goes to get it right. I put my cross channels off the edge of the machine so any shrinkage around the corner would not affect the main rail area. Also I used very slow set epoxy. I’m no epoxy expert but that worked for me.
8:22 this old tony
Couldn’t resist it !
Couldn’t resist it !
Hello...for tapping you dont need a pilot...????
You are right I should have said clearance. Thanks.
What size rails are those hgr20?
Yes the rails are Hiwin HGR20 and are 1150mm long. Carriages are HGH20HA. You can also get slightly shorter carriages (HGH20CA), or flanged mounted (HGW20HA/CA). They were from BST Automation on AliExpress. Thanks.
is there a reason why you didnt get hiwin rails from a reliable source?
Actually I’ve ordered lots of stuff from Fred at BST as have most of the mycncuk forum. Been reliable for years, any issues are sorted, quality and price is good.
i think 0.02 micron is great why you need more precision ?
Do you mean 0.2 mm, the error on the raw box section? If so for a router doing wood work this might be just about acceptable, but for machining metal parts (which is also what I need to do) this is far too much. With the epoxy leveling I am now at about 0.05 mm of variation in rail height (using the tools I have to hand) which is OK for a home build. Thanks.
thanks for reply :)
I don’t understand how it is possible to calibrate a plane according to some piece of plastic (?) on which the indicator stand is based, because it must move along a very even reference plane?
Even if you put the calibration plate, it will stand on the uneven surface of the aluminum profile and in the end you measure the deviation from the plane of the non-curved profile
P.s. possible translation errors google translator, greetings from mother Russia))
It was a piece a granite plate which is quite thick, stiff and fairly flat. I trust it to about 0.05 mm but no more. I shimmed it away from the aluminium until the deviation was minimised just to make the maths easier. Don’t forget I did a best fit line and subtracted this because I only want to know the deviation from straight. Then later I checked that the other rail was in the same plane. Hope this makes sense. Greetings from the UK !
@@routercnc9517 It seems to be understandable, however, I would use a calibration line + a calibration level of known accuracy. Thanks for the answer.
Congratulations beautiful :-)
Thanks
10:01 classic
Sometimes it works, sometimes not !
I thought the whole point of the epoxy was to assure the rails were level. Running an indicator across the top tells you that the base is not parallel with the rails, but you need to shim the base to fix it, not the rails. I hope you have not worked yourself into a corner with that epoxy fiasco. I think you should have stuck to building a machine that was straight and parallel to itself then leveled the table, rather than throw the parallelism out the window for the sake of leveling the rails. And if you are just going to shim the rails to bring them parallel to the base, what was the point of the epoxy at all?
I’m not doing what you think I’m doing. Yes the epoxy was to get the rails level in space but I wanted to know how flat they were (ie local undulations). The indicator was used to measure the flatness of the rails not how parallel they are to the base. The reference plate was placed on the base for convenience and shimmed to get the minimum net movement on the DTI so it would just measure the residual flatness of the rails. I’m not interested in the base itself at this point. You don’t have to shim it to take this measurement but then you need to subtract a best fit line. When complete the base will then be machined parallel to the rails by the machine itself so it will all work out. Thanks.
Indicating off an overhang!!!, probably not the most accurate.
Agree but those were to tools I had. At least I was only getting an idea of the flatness. If I was shimming it in then I would need to do something better. Thanks
precision levelで心出ししないと駄目だよ、機械には絶対水平＆垂直が必要だよ、この方法じゃ何を、何処を基準にしているか分からないよ、
I have just bought a precision level to check the absolute level and across to the other rail. You should see it in the next video. Thanks for your comment.
Here is the google translation from Lucy for anyone interested:
"precision level. You have to center it, you have no choice, the machine needs absolute horizontal & vertical, you do not know exactly what, where this is based on this method,"
Any here my reply translated to Japanese:
私はちょうど、絶対レベルをチェックして、他のレールにまたがって精度レベルを購入しました。 あなたは次のビデオでそれを見るべきです。 ご意見ありがとうございます。
За базу при установке брать заведомо кривой прокат? ну-ну...
Great videos, but you could speed them up a little.
Hi Jason. Thanks for the feedback. I’m still learning on the video creation side and hopefully the later ones are better (up to episode 23 now) but I will keep on trying to improve them. Thanks
Good idea!
But, the question is how flat the surface is? Only liquids have flat and horizontal surface. Semi fluids like epoxy... I am not sure. But, there it is like it is...
Another thing: too much job and effort and too complicated specially because you made two special supporting tools, too many clamping...
Little advice: if it is possible always avoid to do the things on site (cutting, drilling, taping etc). Thinking and planning ahead with the precise work gave the result.
Look, just milling the top and bottom surfaces of the supporting tube on one good and precise machine to make them flat and parallel is good enough. Also, drilling the holes for the screws on that same machine is more easier, wright?
Also, drilling little bigger holes saves time (ex. for HIWIN HGH20CA rail the screw is M5. You can safely drill 6mm or even 7mm hole into the epoxy+tube to allow the space for the adjustment).
To fix the guides you had a far better solution. Look at my solution which is tested many, many times. Video link: th-cam.com/video/YpnX0DQygW0/w-d-xo.html.
The steel bar with the tapped holes will do the better job. The bound between the rail and the supporting epoxy+tube is very strong because you have more than enough depth for the thread in the bar unlike in the relatively thin wall of the supporting tube. So, you can tight them strongly.
The holes are easier to drill and tap on the bar because you do not have to do it on site but away on some machine.
At last, all is easy to mount and easy to adjust the rails.
You are right with those points but I had to do it this way because of a few reasons. I don't have a milling machine so have no way of machining the sections flat, especially at that length.
So I thought I would try the epoxy method and measure the results. Flatness to within 0.05 mm is pretty good for a DIY machine made in my garage.
Also the original design had supported round rail and I had drilled and tapped the holes for that using the CNC mk3. But during this build I decided to buy the linear profile rails, and the holes are in the centre, not the edges, and because the mk3 machine was in pieces I had to drill and tap by hand. I made the drill guides to make this easier, and really quite enjoyed that part. This is just a hobby for me.
On my gantry I did use a reinforcement plate under the rails (as per your method) to make the section much thicker, but on the bed the wall was already 5-6mm which is quite a lot for tapping so just went direct into that.
Now I've done one machine with epoxy I would have to seriously think about whether to do it this way again. Maybe pay someone to machine the longer RHS sections that the rails sit on would end up being better overall. Still, glad I've got this far and can share what I learn with others. Thanks for your comments.
Thank you! Yes, I understand. I am DIY man too. My opinion is that this is very, very serious and very strong machine! So to spend few bucks more for the machining is worth. But I forgot to tell you: I really enjoy your work and I am waiting for the next video. Go! Go! Go!
Thanks Pecilije, very encouraging!
I'm working on the next video, which should include even more measurements of the rails etc. (using the tools I have to hand), and a bit more progress but not ready yet. I can only get into the workshop at the weekend and usually only an hour or so.
Why the crappy music that's sooooo Loud? Didn't watch because of this!
Sorry about that. I just watched it back again and yes it was a bit strong near the beginning. I’ll try to calm it down on the next one so it is less distracting. Thanks
When I saw you building a surface out of epoxy to make a flat surface I thought this guy is just trying to sell epoxy like so many weirdos on the youtube, but when I saw you using a banggood mic I knew you were a shill.
Unfortunately I had to buy the epoxy and it was not cheap. No affiliation or anything there.. If you have access to a large mill that would be quicker and cheaper to level the surface. Epoxy levelling is a popular method on the mycncuk forum, but there are not many videos showing it being used so I thought I would show my first experiences with it. West is a popular choice so I went with that but there are several other brands available.
The banggood mic was a free trial item I was sent and in return just had to put links in the description text box. No kick backs, and not in it for that just want to show my progress and share design ideas with others. Thanks.
Why is it that pricks like you can only crap on a guys effort to share his build experience, Some of us hobbyist machinists can only afford Banggood quality gauges and such but dream of starrett. We use what we can afford but at least we're doing something. When you get off your ass and share something besides criticism, maybe someone will watch, until then don't share your worthless opinions. Maybe a flapping gums video would be a hit?