[ehfeinberg]

With the new products from VexPro and WCProducts, building a quality WCD can be done really quickly with little to no machining capabilities. Just to put it in some perspective, we used only a chop saw to cut the frame members down to length, and a drill press to drill holes for the bearing blocks. And none of these requires any form of accurate machining.

We have used both types of bearing blocks. Both the new sliding bearing blocks, and the older ones. I would highly suggest you go with the new ones because you just need to drill one oversized hole and clamp the bearing blocks on each side and you are done.

I think you are also a little confused about mounting a gearbox. You said that you would use the Toughbox Minis, but if you are to use those gearboxes you will be unable to build a true WCD. A true WCD has the center axle directly connecting the wheel to the gearbox without any intermediate chain/belts/gears, and I think the only way to build with the Toughbox Minis would be to chain the gearbox output to the middle wheel shaft. The part you linked is actually a part of the WCD versions of the gearboxes. Pic Here and link to gearbox.

If I were you, I would just go with using one of the WCProducts gearboxes as long as you can afford them. They are $90 each for a 3Cim single speed, but they are so much simpler to mount into a WCD and reliable. We used them and had nothing but good things to say about them.

In short, sorry if a come off as to pro WCProducts/VexPro, but their new WCD stuff is just so incredibly good that as long as you have the cash to spend, (we spent about $7000 for a 3 cim single speed including tubing/hex shaft/bearings) I would just go with what works really well.