Beltless Drive X-Y Axis (Level 2 - Techie) (Page 3 of 5)

lawsy, at least now we know that both axis experience more than 10 lbs torque. That is good to know. Probably want at least 60 lbs just to be safe.

Other than that are the prints coming out better? I'm curious because the mass of the hot end, extruder, extruder motor, extruder motor fan, plus any cooling fans could be the bigger culprit in over/under shoot during prints. But any little bit of improvement helps and that is what I'm looking for.

I cant wait for the results. I am extremely interested in finding out if this is better than GT2 belts.

So, we need a slicer that has a physical model of the machine and can avoid movements that hit any resonant frequencies :-).

Finally fitted the stronger line on the weekend. I'm not sure it's braided line, looks and feels more like a plastic line. It is rated to 80lbs, however.

Interestingly, the steps per mm for each axis stayed the same this time. So far so good, the print that snapped the thin line completed without issue.

In the pic you can see where one line broke and then the other. The good print is with the new fishing line.

It occurs to me that this is a perfect job for an android smart phone with an acceleration sensor.  Use some rubber bands or something to attach the phone to the print bed, use an OTG cable to control the printer from the phone, then have the phone run the printer through different frequency movements in X and Y and generate a table of the amount of bed movement at different frequencies. No model required, just measure what really happens. Then just need a slicer that understands the table :-).

Updated this line length control thing. Was to hard to get fine adjustment with the old design. Old also flexed to easily. This new one is stiffer and has finer adjustment. Would run it through a drill bit to make sure it spins freely.

Same thingiverse link

My last time wrapping these I did 2-3 wraps on the drive pulley and 1 wrap on the idler. I am not sure if there is any benefit to even the 1 wrap on the idler. Looks like your loop around works fine. I will try that next time I have them off.

Nick,

I would suggest that if the belts are working well enough for you then stick with them. However, If your belts break, you have significant backlash, have trouble tightening them evenly or you just want a project then go ahead and try this out.  I'm not sure that the pattern around the corners will be straightened out by this. I think you should adjust your acceleration settings to fix that. The spectra line seems to go from loose to tight with fewer turns. As always, YMMV.

Let us know how it goes for you if you decide to do this.

I've managed to dial my Y backlash down to 0, which I could never achieve with belts.   By the time I got the backlash low enough with belts, I would get Y skips from too much tension.

New line length control washer works great. Takes up extra slack in the line easily so you don't have to be so precise. Link was above.

Nice job!  Looks great.

Small tip that might help get the tension even on Y axis. After setting up the cables and adjusting the tension, I used a free guitar tuner app on my phone to refine the tension. I plucked the cable and used the app to read the frequency of the resulting noise. I then tuned the tension so the lines had the same frequency. I ran the carriage back and forth a few times and then checked the frequencies again. 

And thanks to everyone above for sharing and showing us how to make this mod.