Tell me about the trunnion rivet

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swilson

Tell me about the trunnion rivet

Post by swilson »

Have been tacking my receiver and fitted my trunnion. The rivet was a little bent from removal so I wailed on it with a BFH til it looked straight. I looked at the tip of the rivet and it appears to have been cut. Did this thing originally extend through the trunnion and was formed on both ends??? Mine does not stick all the way through, it sits just about flush at the end. Am curious to see if I need to order another one when I order my rivet kit.

Would love to see a correct picture of one installed.
oldiron

Rivit head--

Post by oldiron »

On original non rebuilt MG 42's from WWII there was a formed dome on both ends of the trunnion--- Excuse me for not having a picture almost every other 42 I have seen is not done this way-- Originally it had a formed dome on each side of the trunnion ----
narviklied
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New rivets

Post by narviklied »

Is anyone selling new rivets to replace the ones ground off by IO? The trunnion is te heart of the locking system for 42's and a tightly riveted trunnion is a must. I made a few for my guns, but we are doing another batch, and if someone has already done the work...I'd just buy them.
mgfun
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Post by mgfun »

I got a couple from BRP. You might try there.
Regards,
mgfun
mgfun
schaubel777

Post by schaubel777 »

Previous post is correct. Just got off the BRP site. They have every rivet you will need for relatively reasonable prices. Try calling them Monday. I left a message this morning there prior to opening without a reply yet but I know they are working on stuff for us so no hurry.
Dan@AngolaArmory

Post by Dan@AngolaArmory »

I have replacement camming piece rivets, new made, correct OD and length for $10.00 each, shipped.
FWIW,
Dan
propos

Post by propos »

I assume that it is neccessary then to get a new rivet for the camming piece. The old one will not work. The rivet has to have the dome on both ends then? I wasn't aware of that important piece of information. Stands to reason though. What would keep the rivet from backing out under recoil. Guess I'll have to give BRP a call and get one..and the other rivets while I'm at it.
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salt6
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Post by salt6 »

My WWII BRP center reciever chunk rivet was fitted. Hunt had to drive it out from one direction.


salt
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DARIVS ARCHITECTVS
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Post by DARIVS ARCHITECTVS »

The ends of the rivet are almost hemi-spherical. To form the second rivet head after inserting it through the camming pieces, and make it look ORIGINAL, heat the end of the shank to cherry red with a oxy-acetylene torch, support the opposit end of the rivet, and form the head using a ball peen hammer with lots of moderate taps, not heavy strikes, striking glancing blows around the perifery of the shank in an orbiting pattern. Heat it again after it cools, and do some more hammering, making it as deep and round as you can. Keep the heat of the torch away from the camming piece to avoid discolouring it, aiming the torch at the rivet shank only from the side. When it gets close to final shape, finish the shape off to the nice hemishereical shape using a rivet set tool, a steel tool that has a polished, rounded depression that shapes the head into a perfectly smooth and even head. Being a medieval armourer, rivetting is second nature to me now. If you have never done it before, it will present a challenge.
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swilson

Post by swilson »

Ok....I've seen a variety of answers, now lets boil it down to something simple. Do I NEED to replace the rivet or will the one I have that is missing a ground off dome work????? On my receiver rework it had to be tapped in to the cam...it was not loose.

Steve
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Post by panaceabeachbum »

mine works just fine with the origianl rivet, domed head up , lower end expaned slightly with a center punch so it cant slide out.
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Post by rhw1225 »

DARIVS ARCHITECTVS wrote:The ends of the rivet are almost hemi-spherical. To form the second rivet head after inserting it through the camming pieces, and make it look ORIGINAL, heat the end of the shank to cherry red with a oxy-acetylene torch, support the opposit end of the rivet, and form the head using a ball peen hammer with lots of moderate taps, not heavy strikes, striking glancing blows around the perifery of the shank in an orbiting pattern. Heat it again after it cools, and do some more hammering, making it as deep and round as you can. Keep the heat of the torch away from the camming piece to avoid discolouring it, aiming the torch at the rivet shank only from the side. When it gets close to final shape, finish the shape off to the nice hemishereical shape using a rivet set tool, a steel tool that has a polished, rounded depression that shapes the head into a perfectly smooth and even head. Being a medieval armourer, rivetting is second nature to me now. If you have never done it before, it will present a challenge.
Is there any need to support the middle portion of the Rivet? I looks like it could possibly bow in the middle where its unsupoorted.

Thanks,
Robert
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