Steel framed fixed gantry draw slide build super cheap

[Steel]

What your doing is joke in terms of real cnc machine and these Important things should be pointed out for the sake of others who are new and thinking this is acceptable way to do things.It isn't correct or accurate and it will cause problems or fail so he's perfectly correct to point it out:

Why do you think its not acceptable to be creative, innovative, and experimentative and do things differently ? after all there's more than one way to make a chocolate cake right !!!

[A_Camera]

Why do you think its not acceptable to be creative, innovative, and experimentative and do things differently ? after all there's more than one way to make a chocolate cake right !!!

Don't worry, experiment and be creative, nobody wants to prevent you from that, but the solution you came up with is not very experimental or innovative at all, been tried many times before and there are plenty YT movies about it as well. I was there once as well, thinking that it may be possible (but quickly realized it won't fit my needs), and yes, it is possible to do the way you want to do it, but like I said, depends on what your goals are. For learning (the hard way) is fine, for making things with it, it is not. At least not if precision is part of the equation...and you are wrong about the motor bearings, they are NOT made for this sort of job, they are just made for supporting the rotation of their own shafts, not the huge forces a CNC is putting on them, so they will fail pretty fast. But of course, you don't have to believe me, I am just an amateur just like you... I also like to experiment and like innovative solutions, and I learn something almost every day and not always listen to what others have to say, so just continue with your project. I just thought that you may be interested in what others may see but you don't. Of course it is acceptable to be creative. Don't be so childish.

[Steel]

please show me one youtube video of a fixed gantry draw slide build made of steel please, you wont find one !!!

your right us armateur's are just that I got no idea how much a thousands of an inch is in mm i have to google it !!

I can tell you none of my stepper bearings will fail due to direct mount and do you want to know how i know ?

[A_Camera]

please show me one youtube video of a fixed gantry draw slide build made of steel please, you wont find one !!!

That's just three, but there were many in my list when I made a search just by entering "CNC drawer slides" in the search text box. Perhaps I am just lucky, I don't know, but if I say this is not new and not an innovative idea at all, or that there are plenty YT video examples I mean it. As you can see, more than one of those three links are about 5 years old links.

The only reason I commented your build was that you seem to have spent time in making a rigid frame, which is very good, and then weld the drawer slides on that frame, which in my opinion is not a good idea at all, since even if you have some exceptionally well made slides with zero play, you will not be able to square your machine properly.

BTW, I seriously doubt you will achieve 1 micron over 12" and can repeat that over and over again. Perhaps you meant 1 thou (0.0254mm), which if you lucky, you might be able to achieve and if you get that you can count yourself really lucky. More likely, you will get 1mm accuracy or even worse, especially over some time of use, when things start to wear out. I think that 1 micron (0.001mm) is a dream for any home made CNC, even more so for one which is welded at home using drawer slides and lead screws hanging on the motor without properly fixed bearings and curtain rods with delrin slides as Z. I know you won't believe me, but like Jazz said, you are not the only one reading this post, so it is important to point out some facts. Even measuring at that accuracy accurately requires better instruments than most DIY CNC builder can ever dream of. I have 0.02mm (20 microns, worst case) on my machine and I think that is excellent, considering the materials I have used and is definitely more than enough for my needs. But of course, I would not say no to 1 micron... if I could make that for a reasonable cost and in reasonable time (maybe when I retire in a few years time). Having that accuracy on each component is one thing, but once everything is assembled and you start to square... well, that's a completely different thing all together.

Again, that's just my experience and don't let me discourage you, but others who consider making something similar and expecting getting 1 micron accuracy should know that it will be a real challenge with those parts.

Edit:

One link was pasted twice, so only three links are unique so I removed one of the four.

[Clive S]

I think you have one one vid repeated so three shown.

[A_Camera]

I think you have one one vid repeated so three shown.

Fixed. Thanks.

[Zeeflyboy]

What has been pointed out is entirely correct.

If you are just looking for a cheap machine to mill e.g. foam or something then this probably works fine, as pointed out though the bearings on steppers are radial bearings designed for radial loads. They will be experiencing axial loads when trying to drive the screws which is something radial bearings aren't particularly great at... That will result in excessive play, premature wear and eventually failure.

Given that the drawer slides won't allow you to machine anything hard anyway, you will probably be ok on the X and Y (although they will still wear out and develop slop more quickly, and are more difficult to replace than in a separate fixed bearing block for the screw), but given the weight of the router being pulled up repeatedly the Z-axis will probably suffer more.

It also means you are relying on a rigid coupling between the motor shaft and screw, which translates vibrations and resonance into the motor, which again isn't great news. With direct drive really the idea is to have a jaw type coupling with a rubber/flexible insert that provides some protection to the motor. You can't do that however unless the screw is supported by its own bearing set.

I know you think people are being negative or crushing your creativity but there's a reason why things are done a certain way, and it's not creative to go and do things the wrong way just for the sake of being different. To come up with a new solution that actually addresses the reason why things were done in a certain way (e.g. the fact that radial bearings aren't designed for axial loads, and vibration decoupling) whilst doing it better/cheaper/differently is what being creative or innovative would be... just ignoring the issues that cause things to be done a certain way and then doing it poorly to save money is not innovative, it's poor engineering.

You clearly aim to create a cheap machine, on that front you are succeeding. Though how anyone on here is supposed to know what your end goals are when you haven't stated them is ridiculous. Hopefully it's just a fun project for you, and you enjoy making stuff - which is great imo. If you are expecting any sort of accuracy or ability beyond carving some foam into interesting shapes then you are probably going about it in the wrong way.

By the way were you actually trying to infer that your creation will be capable of holding 0.001mm over a 12 inch disc or did I misunderstand that?

[JAZZCNC]

Why do you think its not acceptable to be creative, innovative, and experimentative and do things differently ? after all there's more than one way to make a chocolate cake right !!!

I don't think it's unacceptable to be creative, innovative or experimental. However your not being creative or innovative.? You are being Tightfisted and cheap which are not to be confussed with the latter.! . . . . . If you took the same approach in baking Cake the outcome would be the same.? . . . It would taste Shite and end up in Bin.!

Experimenting is fine and something I fully encourage. But your not inventing or creating anything that hasn't been tried before by others dabbling in CNC. So please don't try to tell others that what your doing is OK and will work fine for CNC machine.! . . . It's not, it's complete rubbish and by the very nature of innapropriate components used along with piss poor engineering is doomed to fail.

So when experienced builders comment don't take it as being negative because they are actually trying to advise YOU and OTHERS against making big mistake.! . . . The time you have wasted on this crap would have been better spent reading the forum and then searching Ebay or selling sites for deals on suitable components. Just like if can't bake Cake better going to ASDA.!

[Steel]

I don't think it's unacceptable to be creative, innovative or experimental. However your not being creative or innovative.? You are being Tightfisted and cheap which are not to be confussed with the latter.! . . . . . If you took the same approach in baking Cake the outcome would be the same.? . . . It would taste Shite and end up in Bin.!

Experimenting is fine and something I fully encourage. But your not inventing or creating anything that hasn't been tried before by others dabbling in CNC. So please don't try to tell others that what your doing is OK and will work fine for CNC machine.! . . . It's not, it's complete rubbish and by the very nature of innapropriate components used along with piss poor engineering is doomed to fail.

So when experienced builders comment don't take it as being negative because they are actually trying to advise YOU and OTHERS against making big mistake.! . . . The time you have wasted on this crap would have been better spent reading the forum and then searching Ebay or selling sites for deals on suitable components. Just like if can't bake Cake better going to ASDA.!

Do you even know why im building this machine and what im using it for ?

[JAZZCNC]

Do you even know why im building this machine and what im using it for ?

Icing Cakes.?