1 Topic by pcm81 (edited by pcm81 2013-05-11 16:25:54)

  • pcm81
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Topic: Has any one tried...?

Just got my doodle3 this week. Fighting backlash etc. Couple questions:

Has any one tried to mod the doodle to use drive screws for X-Y  axis instead of belts? Results?

How about adding 2nd guide rod on each side of Y axis to make belt centered between rods, like it is on X-Axis?

2 Reply by mconsidine

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Re: Has any one tried...?

I didn't try that.  But I did go through the "perfect circles" adjustment video posted by Solidoodle and found that my backlash dropped significantly.  Measured it (y-axis), uploaded lawsy's latest version of the firmware that has the "hysteresis" module and have gotten excellent results in the couple of tests I've done.

Hope that helps,
Matt

3 Reply by pcm81

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Re: Has any one tried...?

Something i just thought about:
Y-axis is the only motor connected by 2 belts in series. This means the total backlash is twice that of X  axis. Could be an interesting mod to try to get the Y-stepper to drive the rear axis directly; removing the 2nd belt and decreasing backlash by 2x.

I may eventually get to it, but don't want to tear up my doodle just yet; only got it this week...

4 Reply by ronsii

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Re: Has any one tried...?

pcm81 wrote:

Something i just thought about:
Y-axis is the only motor connected by 2 belts in series. This means the total backlash is twice that of X  axis. Could be an interesting mod to try to get the Y-stepper to drive the rear axis directly; removing the 2nd belt and decreasing backlash by 2x.

I may eventually get to it, but don't want to tear up my doodle just yet; only got it this week...

I actually thought about doing just that, the easiest way I figured would be to move the stepper outside the case and put a longer y shaft with a direct coupling... but since I haven't had the time and the parts I print are well within spec it probably won't get done for a while.