Is flexible coupler helpful? February 02, 2014 08:38PM |
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Re: Is flexible coupler helpful? February 02, 2014 09:44PM |
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Re: Is flexible coupler helpful? February 03, 2014 01:19PM |
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Re: Is flexible coupler helpful? February 03, 2014 01:42PM |
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Re: Is flexible coupler helpful? February 03, 2014 07:22PM |
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Re: Is flexible coupler helpful? February 03, 2014 08:03PM |
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Re: Is flexible coupler helpful? February 03, 2014 08:09PM |
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Quote
Dirty Steve
...The aluminum couplers are usually 5mm motor shaft to 8mm threaded rod. ....
Re: Is flexible coupler helpful? February 04, 2014 01:34PM |
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Re: Is flexible coupler helpful? February 04, 2014 04:54PM |
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Re: Is flexible coupler helpful? February 04, 2014 07:31PM |
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Re: Is flexible coupler helpful? February 04, 2014 07:39PM |
Registered: 11 years ago Posts: 474 |
thank you somebody finally understands the real root of the problem if somebody is building a machine from scratch and uses stronger Z guides supported it would be nice to see. This is part of the frame and doesn't move I would suggest possibly 16mm supported all the way or real linear rail and bearings. The only extra weight would be the bearings the hard part would be lining everything up there would be no forgiveness because nothing is going to spring so would take somebody with some skill to assemble. Shafts would have to be perfectly parallel if somebody had something that was the right size and used as a gauge to make sure they were exactly parallel top to bottom could be done. jpan has put up a couple more posts and he says it's not happening in the in the right direction so I don't know what would be causing his problemQuote
stonedcoldskier
Check this out: [www.thingiverse.com]
For me, making the change to M6 lead screws solved all of my z-wobble and banding issues. The wobble itself, as CNC_Dick pointed out, is the result of the Z-axis not being as rigid as it should be and the thinner lead screws will flex, allowing the 8mm smooth rods to do their job. Additionally, the change to metric threaded rods with 1mm (M6) or 0.8mm (M5) pitch, along with correct layer heights, will remove any banding issues associated with Z moves which are less than one full step.
There are other posts that will explain things much better than I have, but the comments / discussion on Thingiverse illustrate things pretty well.
Re: Is flexible coupler helpful? February 04, 2014 08:44PM |
Registered: 14 years ago Posts: 1,780 |
Quote
cnc dick
The real root of the problem for all of these machines is that the Z is not strong enough the rods should be continually supported and they should be mounted to a stiff frame. The idea is whatever the screw does it should not push the Z back and forth in other words the linear axis should be stronger than the screw
Re: Is flexible coupler helpful? February 06, 2014 05:35PM |
Registered: 13 years ago Posts: 93 |
Re: Is flexible coupler helpful? February 06, 2014 11:47PM |
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Re: Is flexible coupler helpful? March 06, 2014 05:00PM |
Registered: 13 years ago Posts: 93 |
Quote
brnrd
So, the nut trap is large and allows the nut to wander? So, this trades some lag in the z nuts to eliminate wobble? I think the Prusa2 x-ends may have been intentionally made to have oversized nut traps to do the same thing. That's how my Prusa2 works.