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I know this is a long shot. I am looking for 2 pcs of a non-std nut. #8-40. that is for a screw (stud actually) 0.164" dia with a 40 TPI pitch. I can find all kinds of taps and thread gauges but no nuts. And I only need 2 pcs.

It appears that the 8-40 size is not so un-common in rifles and sewing machines. FWIW, my need is for a sewing machine.

Can anyone help me find these please?

_________________
Chuck.

“Any suspension will work if you don’t let it.” - Colin Chapman

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My suggestion:

Buy #6-32 hex nuts, #28 drill, and #8-40 tap. Drill out the extant threads in the nuts and re-thread. You'll end up with a hex nut that is 1/32" smaller across the flats and 1/64" thinner than a regular #8 nut. There might be a a couple remnants of the #6-32 internal major diameter left on the ID but that shouldn't be a working surface.

AP

Check bolt depot.com or mcmaster carr.com

BoltDepot and McMaster no go. Kind of a special application I guess.

I had bought some thread tensioners for sewing machines from 2 different suppliers on eBay (from China). This is a change I am making on my wife's embroidery machine to solve a problem. One I bought 4 pcs, the other I bought 2 pcs. I needed 6x. Vendor 1 supplied with the nuts, vendor 2 did not. I expected them to be metric and would be no problem to source nuts here. I was surprised when I received the 4 with nuts. Then was surprised again to find them to be 8-40's! Too much running around for only a few bucks, I just ordered 2 more from the 1st guy today.

I was surprised again to see my modification on a new machine 2 days ago from a different maker. Great minds think alike I guess.

_________________
Chuck.

“Any suspension will work if you don’t let it.” - Colin Chapman

Visit my ongoing MGB Rustoration log: over HERE

Or my Wankel powered Locost log : over HERE

And don't forget my Cushman Truckster resto Locostusa.com/forums/viewtopic.php?f=36&t=17766

You're sure they're #8-40? M4x.7 is awfully close.

AP

I've got both metric and English thread gauges. The 40 tpi matches exactly over 5-10 threads. 0.7 pitch not so well. The OD is of the threaded section 0.164".

_________________
Chuck.

“Any suspension will work if you don’t let it.” - Colin Chapman

Visit my ongoing MGB Rustoration log: over HERE

Or my Wankel powered Locost log : over HERE

And don't forget my Cushman Truckster resto Locostusa.com/forums/viewtopic.php?f=36&t=17766

Ok...that certainly sounds like 8-40. When you said you sourced something from China, my thought was metric and I just wanted to throw it out.

AP

Ok chuck I think i have found some #8-40 mach nuts. Ive got 5 but each one is different thickness. PM or email me your address and I'll send them to you.
Russ (the one who never throws anything away) Amos

_________________
You meet the nicest people in a Locost Se7en.

chuck you have a PM

_________________
You meet the nicest people in a Locost Se7en.

I wanted to close this thread out and share some trivia. trialsmangasgas graciously sent me some 8-40 nuts. Thanks Russ. They were however, too small in diameter to fit my threads as delivered. I ended up buying an 8-40 tap and re-tapped the nuts. They were still tight, but with care, I managed to work them back and for the eventually making them fit. I now have functioning thread tensioners added to the thread guides (fabric thread, not machine thread) on my wife's multi-needle embroidery machine.

As Paul Harvey would say, "And now, for the rest of the story." As it turns out, those threads were not 8-40 size as I once thought. They were not UNF or even UNEF threads. I now believe that they were threads designed specifically for sewing machines. As it turns out, sewing machine manufacturers thought they were very clever back in the day. They made screws in non-standard sizes to ensure that any repair parts would be bought thru them. It also appears that watch/clock makers and camera mfgrs made up their own standards along the way too. Some of those odd thread sized managed to continue on to modern machines.

I now believe that the nuts that I needed are truly 11/64" dia x 40tpi made to Nähnorm 100 sewing machine thread standards.

https://www.gewinde-normen.de/en/sewing ... hread.html

Once I found this out, it was easy to search for 11/64-40 nuts online. But now I don't need them!

Who knew there were so many different ways to SCREW things up?

"Well, that's the news from Lake Wobegon, where all the women are strong, all the men are good-looking, and all the children are above average."

_________________
Chuck.

“Any suspension will work if you don’t let it.” - Colin Chapman

Visit my ongoing MGB Rustoration log: over HERE

Or my Wankel powered Locost log : over HERE

And don't forget my Cushman Truckster resto Locostusa.com/forums/viewtopic.php?f=36&t=17766