Nut Bar (4-pack) - P/N: 276-1748 - $4.99 USD/CDN
The Nut Bar consists of a plastic piece with 20-holes sized such that VEX 8-32 screws will self-tap into them. By mounting these bars onto VEX structural metal, you create a series of holes which can be used as nuts. This allows a set of holes that can be mounted to without having access to the back side of the plate.
http://www.vexrobotics.com/products/accessories/structure/276-1748.html
Looks interesting. A few of those would be quite useful on our current robot. Longer delrin bearing blocks would be a nice addition to the product line as well.
If you drill the holes out, they will work as bearings.
-John
So no more having to reach into the maw of the beast? 
Life has become easier! We use a 1x2x35 long full of those things… 
Ah, very nice. Thanks!
Would these be a viable replacement for nylock nuts when used to secure screws at the pivot points of six bar linkages?
Probably not. They wouldn’t be great in that application.
-John
Alright. Thanks for answering so quickly though!
What type of plastic? Delrin?
Yes, they are made from a form of Delrin. We’ll add this note to the product page.
I’m going to try using polycarb stacked up as a replacement for axle holders (bearing blocks).
I’m not sure what I would ever use a nut bar for. Where would you not be able to just use regular old Keps nuts?
because you cant replace that one fallen nut without taking apart half the robot 
When the bearing is inside a C channel, and the keps nuts would stick out into the rotating parts.
Think of the parts count reduction:
Normal: bearing, 2 screws, 2 nuts = 5 parts
Nutbar: bearing, 2 screws = 3 parts
40% reduction
I didn’t check the thickness, but I assume same as bearing flat.
Probably can double stack them and use as integral block and spacer on your in-facing C channel frames.
Think of the easy of axle stackups now, if you can avoid the need for spacers.
Or stack it with a polycarbonate strip to make a close-end hole to hold your axle in.
No more locking collars needed. Think of how much simpler and more reliable your robot will be without locking collars to tightened.
And rather than drill out the axle hole to use it as a bearing, try polishing down the axle from square to rounder, so that it has less friction in the bearing/nutbar.
I think I would rather carve up a bearing block to make it thinner. How strong are the connections between the segments of the nut bar? And are there the 4 little corner pegs that hold the bearing block square in the holes?
If they are self-tapping, wouldn’t that make them not good for axles? Even if you polished the axles and drilled out some of the self-tapping stuff, it would still be soft plastic/rubber touching the axle?
You mean like the soft plastic bearing blocks Vex currently uses?
I’ve scraped off the 4 pegs of each hole on one side of a normal bearing block, and shaved down the thickness of the outer two holes, so I could double stack them, to avoid the need for an axle spacer. Thats still a lot of work and not as clean, and still 4 pieces.
I think I’ll submit a new product idea for 1/2" thick nutbar,
possibly even with 6-32 sized screw holes instead of 8-32.
That way the plastic alignment pegs (if any) can be thicker and sturdier.
I think they are molded plastic, not composite with different self-tapping materials.
JVN said you can drill them out to use as axle bearings.
Good questions through, I’ll have to get some to see.
Bearing blocks are soft, but hard enough to hold axles. I’m not sure how hard the self-tapping stuff is, but I’ll believe JVN about being able to use them as bearing blocks.
I can see how this product could be useful, but it seems like the cases in which they’re needed are few and semi-easily avoidable with some bearing block shuffling.
What I really would like to see is 1/4" pitch metal, but the sturdiness of bar locks. We’ve drilled out the middle square hole of bar locks before to use the bar lock as a bearing block. Or at least some 1/4" pitch metal 1x pieces that you don’t have to buy with $100 of other parts (that you’ll probably never use) would be nice to hold axles together/in line like these nut bars could.
It is all the same material. We found that the size/geometry of the hole lends it self to self-tapping, not the material itself.
-John
Oh, I was imagining something like the new linear slide sleds.
Thanks!