Aluminum builders - Bottle bosses

[mmoore]

Aluminum builders... Im about to start my 3rd aluminum frame and I have a question about the hardest part of these frames - The bottle bosses.

What are you guys using for these?

My first frame I used threaded rivet inserts. Though I question that they will be durable enough and not work loose, leaving me to drill the bolt head off out at some point (frame retired, so no longer a problem in this case)
and the second I used a weld-in type insert but found it difficult to get the tube hot enough to weld without the bottle boss totally melting away (I had a stainless bolt in them which was a part of my fixture so it only melted up to the threads, but it wasn't a clean installation to say the least.

Any pointers on how to do a clean, durable installation?

cheers,
Matt

[progetto]

Rivnuts, most butted tubes are too thin to do it any other way. A properly set rivnut will never move, if you are worried about it, use some epoxy on the inside of the tube to be sure.