SoliForum - 3D Printing Community — Circle diameter vary by 0.3mm. Will the pillow block mod fix this?

Re: Circle diameter vary by 0.3mm. Will the pillow block mod fix this?

2014-06-12T15:36:38Z

I think most of what your seeing is flex in the y-axis drive rod. Try the pillow block and might as well replace those bushings with bearings also. I have a total of 6 bearings on that rod and it made a huge difference. The problem is in finding bearings that nicely fit on that rod. Not because the bearings are hard to find, because the rod is of poor tolerance. I had to spin mine in a drill press and sand it down enough to fit the bearings on.

Re: Circle diameter vary by 0.3mm. Will the pillow block mod fix this?

2014-06-12T14:54:18Z

wardjr wrote:

If your printer is mostly stock in its setup then you are probably just at it's limit for tolerance.

It is very stock, I've only added a glass plate. Does this mean I'm doomed forever to have a part of m circle out by -0.3mm?
I definitely want to replace the jigsaw with lawsy's mod and install the pillow block, but I wanted to have it calibrated as much as possible before I print the parts.
Maybe I need to spend more time and calibrating the y axis IAW the Solidoodle calibration video.

Re: Circle diameter vary by 0.3mm. Will the pillow block mod fix this?

2014-06-12T14:30:12Z

At .3mm it could be anything that is loose or out of adjustment. You can tighten those belts quite a bit without hurting anything but I doubt it will fix your problem. If it is indeed the y-axis you really should try and tweak the steps/mm for that axis. If that doesn't get you what you want then try the pillow block. If your printer is mostly stock in its setup then you are probably just at it's limit for tolerance.

Re: Circle diameter vary by 0.3mm. Will the pillow block mod fix this?

2014-06-12T08:28:25Z

Just how much can I tighten the belts before I see results/risk damaging them. I made 2 full turns of the y axis to tighten the belts and I still have a difference of -0.3mm at 11 o'clock. The rest of the circle is pretty good.

Re: Circle diameter vary by 0.3mm. Will the pillow block mod fix this?

2014-06-12T04:01:47Z

Thanks.
When I print a 5mm stair calibration block, the blocks on the left are 5mm, but the blocks on the right are 5.15mm.
I used the coin belt tension calibrating tool to check the belt tension they both seemed to have the same tension.
My Y-axis motor is pushed down enough to be firm, but not super tight.

Any ideas on whether I should tighten or loosen what components?

Re: Circle diameter vary by 0.3mm. Will the pillow block mod fix this?

2014-06-12T03:32:36Z

It will help some but I would think tweaking your steps/mm for that axis would be the first thing I'd do. Bearings and pillow block on the y-axis drive rod definitely improve accuracy and repeatability. .3 is easily attained just in belt stretch and flex in the drive rod.

Circle diameter vary by 0.3mm. Will the pillow block mod fix this?

2014-06-12T03:22:45Z

Hello,

I've done a few belt tension calibrations and y-axis calibrations and my circle diameters still vary by upto -0.3mm. Would installing the pillow block fix this? Am I asking for too much accuracy from the printer?