Form 3 - more robust roller-holder


#1

It would be great if the roller holder were a bit more robust, or if it were possible to purchase one that is more robust.

The way the roller-holder is currently designed, a very small amount of contamination will result in the roller-holder effectively being destroyed before you have the opportunity to discover there is a problem.

The little v-shaped “nubs” that make contact with the rollers on the top, these appear to be the culprits. My impression is a small amount of resin on the rollers results in friction with the nubs, heating-up the nubs, after which they get worn-down. As the nubs flatten, it results in more friction, eventually causing a vibration to develop as the LPU moves along the rollers. The rollers begin to bind and you get vibration that eventually causes print failures.

Ideally there would be a way to either pre-emptively discover the resin contamination so that you could clean the roller-holder before damage is done, or there would be some way to rebuild the roller-holder after the damage has been done, i.e. have something like replaceable “nubs”.

Perhaps the design can’t be improved significantly. I certainly have to get better at avoiding resin contamination.


#2

My impression is that there is a bit of a non-uniformity in the roller holders. The two rollers in the centre spin with little friction. But the rollers near the ends have considerably more friction. I talked with Formlabs support and they say that’s okay, the rollers are okay sliding along the bottom of the resin tray. That said, why design them as rollers in that case? Presumably some teflon pads would be more effective than binding metal rollers. Teflon pads would be easier to clean after a resin spill, as well.