Backlash Compensation

[volcom7114]

Hello, as a machinist and mechanical engineer, I also have the MakerGear M2 (which is a very good solid machine!), I deal with backlash everyday and since we all know what it is already I'll skip that part to give my two cents on this whole thing. I too was a bit worried about the backlash in the 3D printer when I first got it, as I put it together I noticed that the way they are made (M2) they are very rigid machines that were very well thought out. The first thing and one of the most important things is to make sure that the frame is rigid and has not flex to it under normal movement, if it does start there with your problems but as the MakerGear and all the rest that use ribbed belts and ribbed pulleys that have a set screw which screws onto a flat on the stepper motors, check these as I have seen and heard about them coming lose or being lose in fully assembled models, this would be a good time to add some blue Loctite to the set screws. Now I can only speak on the models I have seen and they both have grooves that the stepper motors screws can slide in to tighten the belt, no matter what belt they make they all have a tiny bit of stretch to them even the anylon corded belts will stretch a tiny bit before they stop and that really has to do with the really high "jerk" loads they are put under when changing direction. When it comes to ball screws on an axis there will be some backlash depending what grade they used and they do wear out over time along with the linear rails, so if it's done a lot of printing for a few years now it may be time to replace a few things.

You can set "offset's" in both the firmware (I think) and S3D but I don't think that would fix any to do with backlash simply cuz each movement will be diff and the offsets will stay the same so it would turn out funky looking lol.

Hope something helps!

[hscharke]

Hallo Kathy,

Look at https://printm3d.com/solutions/article.php?id=80 there is a new backlash calibration guide.
Interestingly, this is exacly the trial & error procedure I used in November to calibrate my backlash and also exacly the same calibration.stl file.
Hope this helps...

Rgds

[Incredibert]

You don't need backlash compensation on 3D printers. The belts are designed to have nearly zero backlash and the forces are very low compared to milling operations.

The main sources for error in 3D printers are flexing of components, linear bearing slop (some printers), temperature effects, setup inaccuracy (axes not perpendicular), loose belts or pulleys, wobble in the z-axis due to forces transferred from the z axis lead screw to the bearing system, and inaccuracies in the lead screws themselves depending on what quality your machine uses.

If you use the z axis retract option then a backlash compensation would be helpful. I don't think they've included it in the software though. I never use it so it doesn't matter to me.

Hope that helps,
Tony

You must be kidding!
Backlash compensation is THE most basic and important setting for 3d printers.
The fact, that it's missing on simplify3D unfortunately renders it useless not only for me, but for any application, which requires decent accuracy especially for small parts.
It's a shame... Such a great program except for that.

Developers, why.. please tell me why!

[andrewk72]

Personally I would agree with Tshulthise and the earlier posters. There's about a dozen other factors with my 3D printer that have a far larger affect on print quality than backlash settings. The belts are designed and tested to have very small backlash, and the Z-screw which may have some typically only moves in 1 direction so it's negligible. So I would say backlash is also a very minor thing and probably not an issue for most 3D printers.

As time goes on and the printers become more precise, it may eventually become more important, but there's a lot of other sources of error right now that are making a much bigger impact.

[tenaja]

You don't need backlash compensation on 3D printers. The belts are designed to have nearly zero backlash and the forces are very low compared to milling operations.

The main sources for error in 3D printers are flexing of components, linear bearing slop (some printers), temperature effects, setup inaccuracy (axes not perpendicular), loose belts or pulleys, wobble in the z-axis due to forces transferred from the z axis lead screw to the bearing system, and inaccuracies in the lead screws themselves depending on what quality your machine uses.

If you use the z axis retract option then a backlash compensation would be helpful. I don't think they've included it in the software though. I never use it so it doesn't matter to me.

Hope that helps,
Tony

You must be kidding!
Backlash compensation is THE most basic and important setting for 3d printers.
The fact, that it's missing on simplify3D unfortunately renders it useless not only for me, but for any application, which requires decent accuracy especially for small parts.
It's a shame... Such a great program except for that.

Developers, why.. please tell me why!

The slicer is the LAST place you want backlash compensation!!! If you put it there, then the g-code file cannot be shared amongst machines, and it is only good as long as your machine stays consistent.

And Tony, to assume every 3d printer uses belts is rather presumptive. Especially considering who uses 3d printers.