Workbee Lead 1000x1000 Wheel Clearance too tight

Some of the CAD models may be outdated compared to current part spec, so I wouldn't go by that alone (as designs get tweaked since inception)
- Eccentrics in the open position? (if the eccentrics is all the way tight it will press the wheel too hard. Adjust them properly.
Of if they are in the wide open position and still does that:
- Is it Genuine OpenBuilds Parts? Contact the vendor you purchased from (or http://support.openbuilds.com/support/home if you bought from us directly) for replacements
- If its not genuine, then consider replacing with genuine parts for guaranteed fitment

 

The Openbuilds Delrin (Black) v-wheels are 23.9mm in diameter. A quick look at Amazon and all the black Delrin wheels sold for 3D printers are 24mm in diameter so that may be where the tightness came from. You could try to drill out the bottom eccentric holes with a 9/32 (7.143mm) inch bit if you have access to one. The bottom holes are more forgiving since the eccentric can help cover up any error you may introduce while drilling. That may loosen them enough. If not then drill out the top holes with a 13/64 inch bit (5.159 mm).

 

I would probably just default to drilling out the bottom holes. Routing the grooves will take off the hard smooth layer that the anodizing provides leaving behind a rough soft layer of bare aluminum. This will probably not wear well and will not be kind to the wheels.

Start with the smallest possible increase in drill size and keep testing as you go for proper fit. On final assembly leave the fixed wheels slightly loose and then tighten them with the Cbeam in place where uniform pressure is holding them to their maximum outside position.

 

One of the holes is a little over 7mm for the eccentric nut. Did you account for that?

 

It is and this can be found in a number of threads over the years, most of them 8-10 years ago. There were a lot of problems with manufacturing tolerances of the extrusion during the early years and this lead to a bit of a moving target with wheel spacing. The best number is nominal extrusion depth + 20.0 mm (depth + 12.0 mm for mini-V wheels) as this is pretty much the sweet spot that covers all tolerance variations.

 

Yes. And if in doubt this is fairly easy to check with digital calipers. Set the wheels in place and measure between the inside edges of the bearings and then add 5mm.

 

Yes, as used on the LEAD machines for example:

 

If you’re getting 8.6mm it sounds like your bearings are not properly seated. This is one of those items that is very consistent. A wheel with (2) 5mm wide bearings and a 1mm shoulder inside should be dead on 11.0mm. Anything else says you either got a bad wheel or your bearings aren’t seated.

With a 20mm groove spacing this makes for a 9mm gap in between.

 

Or not OpenBuildsPartstore.com parts (;