BillFitzmaurice.info

Made from small aluminum blocks.

Made 16 of them.

Installed.

Using 1/4-20, 2 1/4" Stainless Steel socket caps.

I'll use them for the Titans I'm planning for next summer as well.

That's a good idea. Someone should make and sell those. A bit more margin for error than using the h or t nuts.

Great idea.

Some may find it a mission to get the tapped hole perpendicular though.

Thanks Harley, and yes, doing the threads freehand would be tough to get straight. I used a drill press, with aluminum it's no problem. I also made sure to drill thru the wood straight by making a drill bit guide block out of brass.

Aluminum or brass bar stock and a Bridgeport clone for small scale production. A little NC 3 axis mill for cranking out a bunch of them. Sort of overkill, but overkill and margin is a good thing.

Check these out. http://www.pegasusautoracing.com/produc ... ct=MS21059

wallywally wrote:Check these out. http://www.pegasusautoracing.com/produc ... ct=MS21059

They look interesting. If they came as "non-floating" they'd be perfect.




Hhmmmm




Did a google image search for "nut plate", it seems there's all kinds. For example:

http://www.pegasusautoracing.com/produc ... ct=MS21047

The use of sheetmetal nut plates on wood is a new one.

Here's the catch, they're all self-locking. And the manufacturer isn't kidding...

Note: We recommend a drop of oil on the threads the first time a screw is installed in these self-locking nutplates. This is especially important in the smaller thread sizes. We have seen heads twisted off of screws due to the high installation torque even though the nutplates are coated with a solid lubricant. The initial insertion polishes the threads. This slightly lowers the torque during subsequent insertions.

Putting a bolt through one of these is not like throwing a hot dog down a hallway. They hold really tight for aerospace applications (the "MS" designation). They're designed to be held down with rivets which, for a given diameter, are significantly stronger than wood screws (remember 3/32nds is all you're getting) , and fastened to metal (also much stronger than wood). Given so, they don't really provide significant backing area like a T/H-nut or large washer and they're not cheap at ~$50 for a bag of 100. Overkill if someone wanted to pull it off.

I wish the quality control of the H-nut threads was as nice as nut plates though...I never came across a bad nut plate from bench stock in 8 years of fabrication work

Could you run a finishing tap through a nut plate to take the thread out to bigger tolerance?

Unfortunately, not without destroying the tap. MS nut plates are pressed to give them an oblong hole (just like a self-locking nut), then tempered hard. The deformation is permanent.

WB's idea appears to be ingenious workaround if someone was having that much trouble with the H/T-nuts. IMHO.

Plain house-hold vegetable oil works as a good thread lube / sealant too. It dries to a pasty consistency and is non-toxic.

Ahh well... wb's are still nifty, and with a drill press - even a cheap one - it'd take no time to knock out a batch. Just have to set up stops and away you go.