Thread: Rivetnuts/threaded metal inserts

Originally Posted by bee utey

I tried that when I first met these things. The flat bar needs a tiny recess to stop the outer edge of the nutsert from expanding first. All you get is a mangled insert without this groove. Its got to be very accurate. I suppose you could cut the groove with a specially ground drill bit but your bar needs to be harder than stainless to hold the edge of the insert from spreading! The force needs to cause the middle of the insert to expand first.

Interesting.

I’ve just got some 8mm stainless steel one’s and the high tensile bolt and nut to give it a go.

I’ve have some shock tower washers (thick) which I was going drill out to the bolt size to force the rivnut to expand as the nut is tightened thus pulling the bolt up as it collapsed the rivnut. Sounds so simple?

I’ve never seen a rivnut tool but I can envisage what you’re saying.

I suppose you could use a *flat end drill/end mill to “nick” the small recess. Even if it was a bit oversized as the rivnut bit it should be OK?

*For non technical people like me the flat drill/end mills are designed to drill and leave a flat bottom hole if you don’t go completely through

Originally Posted by scott oz

Interesting.

I’ve just got some 8mm stainless steel one’s and the high tensile bolt and nut to give it a go.

I’ve have some shock tower washers (thick) which I was going drill out to the bolt size to force the rivnut to expand as the nut is tightened thus pulling the bolt up as it collapsed the rivnut. Sounds so simple?

I’ve never seen a rivnut tool but I can envisage what you’re saying.

I suppose you could use a *flat end drill/end mill to “nick” the small recess. Even if it was a bit oversized as the rivnut bit it should be OK?

*For non technical people like me the flat drill/end mills are designed to drill and leave a flat bottom hole if you don’t go completely through

No I'd go as exact as possible. Once the rivnut starts to squash you want it to happen exactly right. I would try and sharpen a matching drill bit like my picture: I use this one for thin sheet metal as it leaves much thinner burrs (not my idea, passed on by a sheet metal guy).

Originally Posted by bee utey

Wouldn't be able to live without my nutsert gun, Textron brand, made in England, bought through Coventry Fasteners (was Universal Fasteners) in Adelaide.

Well I bit the bullet and got myself one of those--reassured that it could do s/steel up to M6-- b*****t-- OK I could not put on any more pressure without going to some extreme leverage and probably breaking something,mandrel or tool as indicated previously. Well Im now thinking do I really want s/steel-- bugger it , no, Ill put in s/steel bolts and washers and hey! if this was a boat maybe I would really want s/steel. Thanks for your offer Dave, Ive used the "thin metal inserts/ aluminium?" and they seem pretty tough anyway but Ive been thinking oooooo Ive got some more use for this yet---trailer/fishing rod rack etc.
Steve

the standard ones are what holds the IMV together.

cant think of what you'd do on a rover that'd be any tougher