Belt tensioning and backlash

I am always interested in absolute resolution that can be had, and I am not a pro at such fine details. I do like to pay close attention to those willing to chase zeros as I almost always learn something from it.

I am also thinking about new designs and revisions, so if there is a way to make something better without new hardware I pay extra attention.

1 Like

I found some resources and I don’t know how viable it would be but it seems using either steel or kevlar core belts can make a big difference to the deflaction that i’ve measured.

This video goes into detail (It’s for a shapeoko but i believe it’s a similar setup as what we see in the LR3)

That specific section is about the belts but there’s 3 videos in the series and it seems to me they’re really worth watching (the whole channel really as there’s only 5 videos sadly), quite a good applied engineering class if you ask me.

2 Likes

Sorry about that, in this part of the world there’s only one way of measuring things right XP.

Jokes aside I should have added the units and yeah, I meant 0.06mm and it’s plenty for my needs, I just like to play around and see where that gets me. Originally I built the LR3 as a machine for large parts that dont really need much more than ~0.5mm of precision.

Yeah, I believe the idea is to have the precision at least without load, obviously tolerances come into play since load, speed and ultimately deflaction are what really matter for cutting. Actually the person that opened the ticket in fluidnc refers to name-brand machines using said setting to compensate backlash (coming from wear maybe?) even though their machines probably don’t need it. I guess I find it a nice option to have even if it isn’t a silver bullet.

We can not use steel belts. Those can not handle small radius bends. They fail in minutes to hours.

It is also always best to include the base dimension as well. for example 0.06mm over 1200mm is amazing. 0.06mm over 12mm is still amazing but less so. This gives outside eyes just browsing a frame of reference so they can understand what level of accuracy real users get.

Anything under 0.3mm over a 200mm cut is very good in my opinion.

1 Like