# PEM Nut Kits and Shear Pins Kits?

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TRF Supporter

#### deandome

##### Well-Known Member
mtnman, where did you get the metal 'countersink reinforcements', and how are they fastened/implanted in the outer tube/nosecone?

#### mtnmanak

##### TRA & NAR L2
TRF Supporter
mtnman, where did you get the metal 'countersink reinforcements', and how are they fastened/implanted in the outer tube/nosecone?
Those are Lumadyne nuts/washers. You can find them at Apogee:

There was a time when you could buy them straight from the manufacturer and I got a whole bunch of them in bulk. Now, it appears you can only get them from Apogee. Too bad, they are pretty slick and Apogee is selling them at a premium.

Once my current supply is gone, I am not sure I will buy them at $5 a pair. I have been looking around for a replacement, but have not found one yet. #### Pete.D ##### Ex Rocket Scientist TRF Supporter 2-56, 4-40, and 6-32? Or is 2-56 too small in your opinion? Pem nuts are real handy, and very durable compared to plastic rivets. I'd be interested in a set of each of those sizes. #### rfjustin ##### Well-Known Member Last call folks.... finalizing order to McMaster this week. #### teepot ##### Well-Known Member TRF Supporter Last call folks.... finalizing order to McMaster this week. How many are you planning to have with each kit? #### rfjustin ##### Well-Known Member How many are you planning to have with each kit? 25 or 50, depends on what quantity said thread/size is sold by Mcmaster. I don't plan to split up quantities if that makes sense. #### teepot ##### Well-Known Member TRF Supporter 25 or 50, depends on what quantity said thread/size is sold by Mcmaster. I don't plan to split up quantities if that makes sense. Depending on the cost I would be interested in the sizes mentioned in a previous post. #### rfjustin ##### Well-Known Member Depending on the cost I would be interested in the sizes mentioned in a previous post. Didn't see your previous post...? What are you needing please? #### teepot ##### Well-Known Member TRF Supporter Didn't see your previous post...? What are you needing please? 25 of 2-56 and 25 of 4-40. If 50 is what is in a kit I'll take that. #### Idunno ##### Well-Known Member I'm assuming by now you placed the order. But if for some reason you have extras i'll give some a try since i'm almost out of rivets. Current project is 3" so I guess some 4/40? And whatever the next smaller size is for a 54mm. #### deandome ##### Well-Known Member Not to poop on the fun & comradeship this kinda thing brings out, but I needed pem nuts now, and got 2 sizes of knockoff 'self cinching nuts' on Amazon @$8.00 per bag of 50 https://www.amazon.com/dp/B08XYJXJRC?psc=1&ref=ppx_yo2_dt_b_product_details

Delivered free in 2 days, they seem perfect enough for me, 'cept you can select 3 different 'thicknesses' of the toothed, grippy-sections, and I went with the thinnest one. No biggie, but I'd recommend you go with the medium-size