oli
Apprentice
Posts: 1,065
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Post by oli on Sept 14, 2017 11:24:17 GMT 1
Can anyone give me advice on "setting" solid rivets? (I'm not talking about pop or blind rivets but the old type that need hammering - a bit like ships rivets but done cold, rather than red hot!)
I've seen several videos where a concave punch is put over the pre-mushroomed head and a heavy piece of flat metal (bucking bar?) is put behind it to act as an anvil. This leaves one side like a mushroom and flattens the other. I think this is known as an aircraft rivet.
My question is, how do I form a round head on both sides - like the originals I'm replacing? Can you get dimpled bucking bars? Hammer or press an old ball bearing into a lump of scrap steel? Or hammer the flat end with mu punch - the opposite of what you would usually do?
It's an early type (1960's) Land Rover tail board/gate I'm fixing for a bit of fun.
Oli
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Post by chippie on Sept 14, 2017 12:27:21 GMT 1
Oli,
It is usual to use a rivet snap to 'set' the rivet.....
Assuming you are using single headed rivets, one snap goes over the preformed head, then the remaining head is peened over using a suitable hammer....( a ball pein hammer would you believe...), the final shape being achieved by the use of the second rivet snap....This would create a double headed rivet, for a single head, you would need to pein over the end on the non- visible side of the panel....
What material are your rivets made from?
I'd assume they are aluminium, in which case they should be annealed before riveting so they are malleable for forming....
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Post by Noberator on Sept 14, 2017 15:08:02 GMT 1
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oli
Apprentice
Posts: 1,065
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Post by oli on Sept 14, 2017 19:30:31 GMT 1
Thanks Chippie and thanks Noberator for making me groan ;-) it sounds like I need a second rivet snap (I got one with the rivets). I've just had a play with them and they are surprisingly hard (though they are aluminium as you guessed). Annealing sounds like a good idea.
I see you can get snaps that fit into air chisels. The videos I've seen make it look a doddle with one - I suspect it isn't!
Oli
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Post by chippie on Sept 14, 2017 19:33:56 GMT 1
When you anneal the rivets, be careful not to overheat them, you could end up melting them.....
MP of aluminium is around 630 C Iirc.....
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Post by Noberator on Sept 14, 2017 20:30:36 GMT 1
When you anneal the rivets, be careful not to overheat them, you could end up melting them..... MP of aluminium is around 630 C Iirc..... It's 660°C Chippie.  When I was 18 (old enough to work shifts back in the 1970's ) I worked for an Aluminium company making aluminium ingots and billets.  Aluminium Alloy varies. Melting table.Alloy 3003 IIRC is the most widely used of all aluminium alloys. A commercially pure aluminium with added manganese to increase its strength (20% stronger than the 1100 grade). It has excellent corrosion resistance and workability. Sorry Headmaster lesson over.  See thread for details. |
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oli
Apprentice
Posts: 1,065
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Post by oli on Sept 14, 2017 21:22:53 GMT 1
I seem to remember from DT at school that a little bit of soap can be a useful temperature indicator?
Oli
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Post by chippie on Sept 14, 2017 21:41:38 GMT 1
Oli, You are indeed correct....I was taught the same when I did metalwork at school.... I'm sure Nobster will confirm from his days working with the local blacksmiths....  .....( light hearted banter...) On a more serious note...trying to offer constructive advice.... Problem is, that, the rivets are fairly small, so looking for a streak mark of soap on a rivet is going to be pretty difficult..... Now if you had access to an electric furnace..............you could set the temperature to the desired setting and anneal that way...but as you havent.... I'll consult with some model engineer friends to see if they can offer any advice....but dont hold your breath....many of them are 'armchair modelers' who dont actually have any practical experience but consider themselves experts..... However!! You could ak your supplier if the rivets are supplied in an annealed state.....save you doing it.. I'll be back.... |
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oli
Apprentice
Posts: 1,065
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Post by oli on Sept 14, 2017 22:18:53 GMT 1
Yeah, I'd feel a bit of a tit if I went to all that trouble and found the' already been annealed!
I'm thinking thick scrap steel plate with some holes in it, rivets sitting in the holes and a little blob of soap on each then some gentle heat underneath from either a blow torch or even prop it up over a gas ring on the cooker (if the wife is out).
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Post by Noberator on Sept 14, 2017 22:32:40 GMT 1
Oli, You are indeed correct....I was taught the same when I did metalwork at school.... .....( light hearted banter...) On a more serious note...trying to offer constructive advice.... Problem is, that, the rivets are fairly small, so looking for a streak mark of soap on a rivet is going to be pretty difficult..... Now if you had access to an electric furnace..............you could set the temperature to the desired setting and anneal that way...but as you havent.... I'll consult with some model engineer friends to see if they can offer any advice....but dont hold your breath....many of them are 'armchair modelers' who dont actually have any practical experience but consider themselves experts..... However!! You could ak your supplier if the rivets are supplied in an annealed state.....save you doing it.. I'll be back.... My flabber has never been so gasted Well I do like heavy metal still. |
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Post by valhalla on Sept 14, 2017 23:43:09 GMT 1
Thanks Chippie and thanks Noberator for making me groan ;-) it sounds like I need a second rivet snap (I got one with the rivets). I've just had a play with them and they are surprisingly hard (though they are aluminium as you guessed). Annealing sounds like a good idea. I see you can get snaps that fit into air chisels. The videos I've seen make it look a doddle with one - I suspect it isn't! Oli I've only done copper rivetting like this (cold-riveting), and a second snap is the way to do it, with the first well and truly solidly mounted to a block of steel. It's a three-handed job, but you still want to ensure that the preformed head is the one that needs to be cosmetic; I never really got the hang of getting the second snap square over the rivet! If you can get the workpiece over the bench, then mounting the anvil to a vice and working downwards (cosmetic side down) is the easiest way. One hand to steady the workpiece, one to hammer (oh, and the third to hold the second snap..... ) I have aluminium rivets pre-annealed, but they seem to be intended for aircraft work? |
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Post by Noberator on Sept 15, 2017 0:03:45 GMT 1
When you anneal the rivets, be careful not to overheat them, you could end up melting them..... MP of aluminium is around 630 C Iirc..... It's 660°C Chippie. When I was 18 (old enough to work shifts back in the 1970's ) I worked for an Aluminium company making aluminium ingots and billets. Aluminium Alloy varies. Melting table.Alloy 3003 IIRC is the most widely used of all aluminium alloys. A commercially pure aluminium with added manganese to increase its strength (20% stronger than the 1100 grade). It has excellent corrosion resistance and workability. Sorry Headmaster lesson over. See thread for details. Mrs Nobster seems to think you had to be 21 back in the 1970's to work shifts?  It was a long time ago so may be she is right.  WOMEN |
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Post by valhalla on Sept 15, 2017 0:17:48 GMT 1
Mrs Nobster seems to think you had to be 21 back in the 1970's to work shifts? Only in the "oldest profession".  |
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Post by chippie on Sept 15, 2017 7:24:27 GMT 1
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Post by chippie on Sept 15, 2017 11:27:45 GMT 1
Update
Oli,
If you read the thread link I posted, it has since been updated. Andrew Johnson's post being the most appropriate, he is a well known knowledgeable chap, so his advice is sound....
Hope this helps....
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