Julian B
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| posted on 19/3/04 at 08:32 AM |
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Riveting
Hi
Are there any alternatives to pot riveting? Although pot riveting leaves a nice finish on the top surface the underside looks cack. What did/do they
use in the aircraft industry to get those nice countersunk rivets? Obviously pot riveting is fine in some places but in others it would be nice if
there were a more elegant method.
Cheers all
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Staple balls
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| posted on 19/3/04 at 08:53 AM |
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what are you riveting to where? different methods are more suitable to different places.
all my internal panels (apart from the tunnel) will be glued on
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Mix
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| posted on 19/3/04 at 10:18 AM |
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Aircraft riveting
Aircraft rivets are generally set using the reaction process. The head of the rivet is hit using an appropriatly shaped punch, (dolly) whilst a heavy
smooth metal block is held on the tail. This forms a fairly flat cylindrical head (on the tail). Alternativley the rear of the work can be countersunk
and the rivet formed into the recess to give a flat surface on both sides. If you have a compressor and an air chisel you can adapt them for setting
solid rivets by either reducing the compressor output pressure or restricting the flow to the chisel. For countersunk head rivets you need to adapt a
chisel so as it has a circular end of about 25mm in diameter with a very slight domed profile and smooth surface.
Hope this makes sense
Mick
[Edited on 19/3/04 by Mix]
[Edited on 19/3/04 by Mix]
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Peteff
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| posted on 19/3/04 at 10:38 AM |
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POP rivets
where will you see the undersisde of the rivets? All mine are inside the RHS tubing where you can't get at the backs to peen them over
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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David Jenkins
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| posted on 19/3/04 at 12:19 PM |
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quote:
Originally posted by Mix
If you have a compressor and an air chisel you can adapt them for setting solid rivets by either reducing the compressor output pressure or
restricting the flow to the chisel. For countersunk head rivets you need to adapt a chisel so as it has a circular end of about 25mm in diameter with
a very slight domed profile and smooth surface.
Mick,
What sort of air pressure are you talking about - I'd like to try this with my air hammer.
Did you take an ordinary air hammer bit and hack it around?
David
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Julian B
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| posted on 19/3/04 at 12:19 PM |
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Sorry POP rivets.... doh
I was clearing out the garage and i came accross an alli boot cover i had made up for my old car. Yep most of it is into tubing so you dont see the
back of the rivets.
I still dont see how you get the tension with the aircraft syle rivets as you do with the POP rivets. Perhaps i am being a bit stupid!
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Jasper
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| posted on 19/3/04 at 12:55 PM |
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I've used countersunk rivets, you need to buy the appropriate countersinking drill bit to go wth them
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Mix
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| posted on 19/3/04 at 01:04 PM |
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David
It's difficult to give a pressure as it depends on how efficient the air chisel is. Air riveters have a much 'softer' action,
reducing the pressure on an air chisel will however give an acceptable comprimise. Reduce the pressure until when the chisel is operated against a
block of wood it makes a similar sound to fairly firm rapping on wood with your knuckles.
Yes just adapt a bit or get something turned to suit.
Julian
Solid rivets are stronger in both shear and tension than normal pop rivets due to the increased cross sectional area. The action of setting them
sqeezes the joint together and expands the rivet into the hole much more efficiently than a pop rivet.
Mick
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stephen_gusterson
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| posted on 19/3/04 at 01:08 PM |
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just look at a ship for example, gadzillions of blind rivets - and they dont leak either - so must be a tight fit.
Still amazes me how many rivets there are in an aircraft wing - looking outa the window last week, they were double stagered rows, approx 2 ins
between each row's rivets. (747)
atb
steve
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Julian B
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| posted on 19/3/04 at 02:35 PM |
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I thought that iron rivets on ships were put in hot and the cooling and contraction of the rivets pulled the plating in tight
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stephen_gusterson
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| posted on 19/3/04 at 09:55 PM |
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possibly - but the contracting is actually gonna give a loose fit in the hole - must be the hammered head that seals it.
atb
steve
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suparuss
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| posted on 19/3/04 at 10:01 PM |
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what is it you are fixing then? have you considered bolts? if there isnt enough depth to thread the hole you could use expansion inserts, which dont
look as bad as rivets from the rear.
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Peteff
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| posted on 19/3/04 at 10:40 PM |
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Ships were built with rivets peened over from both ends like boiler construction. Watch Fred Dibnah, he'll show you. Some poor bugger had to be
at the back of the plate with a rivetting gun to round the head over. Ships haven't used rivetted construction since about the 40's have
they?
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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Spyderman
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| posted on 20/3/04 at 11:04 AM |
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quote:
Originally posted by Julian B
I thought that iron rivets on ships were put in hot and the cooling and contraction of the rivets pulled the plating in tight
The rivet is put in hot and the other side is hammered over.
Then when the thing cools it clamps the plating tighter.
There is more shrinkage in it's length than it's diameter.
Spyderman
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DaveFJ
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| posted on 20/3/04 at 05:09 PM |
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The reason for fitting 'ship' type rivets hot has more to do with the material itself....
an average rivet in a ship is huge and would be almost impossible to reaction. Heating the rivet simply makes it softer.
when using conventional riveting techniques you should always have the the materials clamped firmly together. the rivet fills the hole provided but
will not 'clamp up' like a blind rivet would. A well formedrivet will retain the level of 'clamping' when the grips are
removed. As an aside I would not recommed using the spring type clecos when using solid rivets, they do not provide enough pressure. Go for the manual
thumb screw type instead.
saying that it is always best practice to ensure that materials are firmly clamped together before blind riveting as well.......
Dave
"In Support of Help the Heroes" - Always
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Jasper
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| posted on 20/3/04 at 05:21 PM |
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Hey boys, I'm sure there is a forum out there for people building ocean liners in their back gardens - BUT THIS ISN'T IT 
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Mark Allanson
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| posted on 20/3/04 at 06:05 PM |
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Speak for your self, I have just laid down the keel for a replica of the Queen Mary, cannot decide to use Pinto of Zetec though
If you can keep you head, whilst all others around you are losing theirs, you are not fully aware of the situation
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Carl.H
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| posted on 20/3/04 at 06:35 PM |
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Pinto for the anchor and the zetec to power it 
I drink to make other people interesting.
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britishtrident
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| posted on 20/3/04 at 06:50 PM |
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Many many varietys of pop rivets you can use stainless steel closed end for bit that show and need strength --- expensive ! Plain steel are more
suiable for parts that are to be painted.
Countersunk are only available in aluminium alloy.
See http://www.rivetwise.co.uk/product/index.htm
[Edited on 20/3/04 by britishtrident]
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type 907
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| posted on 21/3/04 at 09:41 PM |
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Hi,
I'v been looking at Clecos, they look useful, http://www.lightaero.co.uk
Loads of bits & bobs on this site.
Paul G  
Too much is just enough
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andrew-theasby
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| posted on 22/3/04 at 01:30 AM |
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There are loads of different rivets used in the aircraft industry. The solid rivets arent much use on our cars as you need to get to both sides and
theyre solution treated then age harden so you only have 2 hours to get them in or theyll crack. The blind ones can be countersunk or raised heads
but most, ie cherry's, mbc's olympics etc need a different gun to a normal pop gun as they have locking rings or odd sized mandrells. The
best ones to use are the ordinary steel 100 degree countersunk ones that look like a normal pop rivets but you need to either punch the ball part of
the mandrell out or araldite it in. They can then be milled flush and invisible when painted. its best to use some kind of sealant between the
joints to avoid fretting as the whole idea of rivetting is to allow things to move slightly and it stops disimilar metal corrosion. The top material
needs to be at least 1mm or the csk will break through and the hole needs to be fairly accurate in diameter too. Hope this helps
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DaveFJ
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| posted on 22/3/04 at 01:08 PM |
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quote:
Originally posted by andrew-theasby
The solid rivets .... and theyre solution treated then age harden so you only have 2 hours to get them in or theyll crack. . The best ones to use
are the ordinary steel 100 degree countersunk ones that look like a normal pop rivets but you need to either punch the ball part of the mandrell out
or araldite it in. They can then be milled flush and invisible when painted......the whole idea of rivetting is to allow things to move slightly and
it stops disimilar metal corrosion.
Remind me to never let you near an aircraft..............
no,no,no,no and err no!
Cheers
Dave (an Aircraft Engineer)
[Edited on 22/3/04 by protofj]
Dave
"In Support of Help the Heroes" - Always
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David Jenkins
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| posted on 22/3/04 at 01:30 PM |
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quote:
Originally posted by protofj
Dave (an Aircraft Engineer)
Dave,
Perhaps you can answer a vaguely relevent question - I once went into an RAF aircraft maintenance hanger in St Athan, and saw a technician rivetting
an ali skin onto the tail of a VC10 (one of their tanker aircraft).
What puzzled me is that he was using an air hammer on a fully closed-up wing (i.e. no backing anvil) - how did he manage that? The only thing I can
think of is that there was an inspection hatch that I couldn't see - but I'm sure there wasn't!
cheers,
David
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DaveFJ
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| posted on 22/3/04 at 01:47 PM |
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David,
Little idea - sorry.....
the process does require a reaction block to be placed behind the rivet being worked. I can only assume that there was a block being held in by some
sort of clamp ?
I have seen a similair situation where it would have appeared that there was no reaction block, this was whilst riveting the tail boom of a
helicopter. there was in fact a guy (the smallest on our crew) tucked up inside the boom and at full stretch he could just get onto the back of the
rivet....
took bloody ages to get him back out though
Dave
"In Support of Help the Heroes" - Always
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andrew-theasby
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| posted on 23/3/04 at 12:33 AM |
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Thats what i do for a living. Whats wrong with what i said about the solid rivets??? The guy on the wing skin might not have been putting rivets in,
but more likely putting hi-tigue bolts in. these are an interfernce fit, so thats why he was using the rivet gun to hammer them in. There used to
harden the metal arond the hole (ie HIGH faTIGUE bolts)
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