<![CDATA[SoliForum - 3D Printing Community — Circle Calibration]]> https://www.soliforum.com/topic/8962/circle-calibration/ Thu, 01 Jan 2015 21:58:03 +0000 PunBB <![CDATA[Re: Circle Calibration]]> https://www.soliforum.com/post/77129/#p77129 need this topic merged with the other already huge similar one

]]> Thu, 01 Jan 2015 21:58:03 +0000 https://www.soliforum.com/post/77129/#p77129 <![CDATA[Re: Circle Calibration]]> https://www.soliforum.com/post/77121/#p77121 I agree on the reduced friction but I don't see the hole being slightly bigger than the rod being a cause of significant backlash on a 3d printer.
The rods aren't perfect either, as well as linear bearings, aren't they?
When you put on and tighten the belts it would be even less likely I think.
Just some thoughts.

]]> Thu, 01 Jan 2015 20:23:07 +0000 https://www.soliforum.com/post/77121/#p77121 <![CDATA[Re: Circle Calibration]]> https://www.soliforum.com/post/76961/#p76961 The makerbot in our lab is old so keep that in mind. It's an early replicator without an enclosure or heated bed.

The makerbot in our lab uses bushings to slide along the X and Y rails. These are not ball bearings (like LM8UUs) and they rely on tolerances and the properties of whatever they're made of (bronze, I think) to slide. This means they have significantly more slack than bearings because the hole is much bigger than the rod to allow sliding. The lack of reciprocating balls also means they have more friction. So each move by the motors to change direction has to pick up the slack, and overcome the high static friction. Beyond that, kinetic friction is also an issue.

]]> Tue, 30 Dec 2014 16:45:59 +0000 https://www.soliforum.com/post/76961/#p76961 <![CDATA[Re: Circle Calibration]]> https://www.soliforum.com/post/76956/#p76956 Wait, Makerbot doesn't use bearings?
And what do you mean by "slop in the linear bushings". Tell me more. At that cost I'd expect more from them.

]]> Tue, 30 Dec 2014 15:58:36 +0000 https://www.soliforum.com/post/76956/#p76956 <![CDATA[Re: Circle Calibration]]> https://www.soliforum.com/post/76952/#p76952 Not sure about the drive system on your particular Makerbot but the one in our lab has about 0.2mm out of round we never could eliminate. I suspect it's either from slop in the linear bushings or a problem with the back rod and/or its drive belt--it is pretty much the same Y axis design used by Solidoodle.

The answer is probably no. Not without modification. Upgrade everything to bearings.

]]> Tue, 30 Dec 2014 15:18:06 +0000 https://www.soliforum.com/post/76952/#p76952 <![CDATA[Circle Calibration]]> https://www.soliforum.com/post/76947/#p76947 I ran the Circle calibration print(link below) and I am out .18mm on X &* Y axis do you think I can get it dialed in closer?
How accurate can you get them?

]]> Tue, 30 Dec 2014 14:33:40 +0000 https://www.soliforum.com/post/76947/#p76947