Have you guys encountered Xtreme V-wheels cracking? I'm building an R7 design cnc and followed the instructions. I don't think I tightened them too much because the wheels are still freely moving yet they crack. I also noticed that they are cracking only on one side. If tightened too much, I think they would crack on both sides.
Are those from Openbuilds Part Store, or China? I bought few cheap ones out of curiosity and the precision spacers were not very precise. Also, they cracked like that. In fact they cracked all the way through. So far 7 for 10. At least I was able to re-purpose some of the bearings.
I just had to replace some mini-v-wheels on my router after they had cracked. Two had cracked in half and one other had visible cracks in it. The ones I had were directly from Openbuilds. I think they just can't stand up to the prolonged stress. And I think that the 'mini-wheels' are less robust than normal sized solid v-wheels. I'm redesigning my router right now. And I will be using standard solid v-wheels. No more xtreme mini-wheels for me. -D
Just the mini or all the extreme? I just placed an order for a project. Might have time to change it.
They are from openbuilds. I haven't even used mine, I'm just about to build my cnc. Is it possible that the bearing are slightly over-sized so when I tighten them, the wheels crack? I'm still waiting for supports reply.
Sounds like the parts store may have gotten a bad batch. I have ones nearly two years old that are perfectly fine and in the roughly two years that the Xtreme wheels have been on the market I don't recall any previous issues with the mini-Vs. There were some issues with them getting nicked by the actuator screw collars but that's a mechanical issue not a product deficiency. Best suggestion is to wait for OBPS support to get back with you. They will take care of you but more importantly also trace the problem to the source so it doesn't spread any further.
I'm delaying my build till I get a reply. These wheels are not cheap and i'll be using over 60 wheels for the build.
The wheels that cracked on my machine were the ones under the most stress after about 6 months of heavy use. The other time I somebody posted about this was similar. It happened on wheels under a lot of stress over a long time under heavy use: Strong OX So it sounds like this is a different issue than what aj1 is seeing. They should definitely not have any troubles with you putting the bearings in them for the first time. -D
Yes, the results from the Strong Ox are the reason why the regular Xtreme V-wheels are no longer sold in the parts store. Totally inappropriate use of the material.
So these are regular extreme wheels and not the extreme solid wheels available let at the parts store now?
Yes, the V shaped ones not the solid ones. Polycarbonate is great in compression but the tensile forces created from riding along a pointed edge was splitting them in half.
Thanks, That's a relief. I did a parts store order yesterday. More than a few wheels in that package.
I would like to revisit his issue... I have six of the X-Treme Vwheels that have cracked in half or partially in random locations on my Lead 1010. I would think that if I was over tensioning them they would fail in pairs. Example, one at the eccentric and the one on the opposite side of the Cbeam. Not the case with me. They are in random locations. I even have one failing on the Z axis which in my mind should be the least stressed of all axis’s. I have only had my my machine since October 2019 and used only as a hobbyist. any suggestions or comments welcome. Larry DeSoto
