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Post by ron on Feb 27, 2007 10:40:18 GMT
Hi Everybody, I'm about to start fitting hornblocks to frames, the frames are MS and the hornblocks are gunmetal, should I use copper or iron rivets? please don't say steel, I haven't got any ;D
Ron
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Post by baggo on Feb 27, 2007 10:55:56 GMT
Hi Ron,
it's usual to use soft iron rivets. Copper have a tendency to work loose eventually. Put them in from the horn side, hammer them into countersinks on the outside of the frames and then file flush.
John
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jackrae
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Post by jackrae on Feb 27, 2007 11:57:03 GMT
This raises the question as to the meritrs of using bolts for fixing the hornblocks.
After all they will have greater shear strength than rivets and be "easier" to fit.
I remember trying to use all three hands whilst riveting my Simplex blocks - two to hold the frames balanced on top of the rivet set (held in the vice) and one to wield the hammer.
jack
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Post by ron on Feb 27, 2007 15:23:05 GMT
Cheers John, iron rivets it is. Jack, I actually quite like rivetting for some strange reason, well the first couple of dozen any way then the novelty sort of wears off, looks like I'll need to make a special narrow rivet snap, the access where the stiffening ribs are on the horns is a bit tight. Ron
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Post by baggo on Feb 27, 2007 15:34:03 GMT
For my last horn riveting job I had to make a narrow snap to fit in as well. Just used a bit of silver steel countersunk slightly with a drill and then 'biffed' onto a suitably sized steel ball bearing to make the depression after heating the end. I got around the 3 hand problem by resting the frames on some suitable blocks of wood to keep it level and at the right height.
John
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Post by ron on Feb 27, 2007 15:36:06 GMT
John, did you harden and temper the snap? The wife's just been promoted to assistant chief rivetter. ;D Ron
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lancelot
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Post by lancelot on Feb 27, 2007 15:41:47 GMT
Hi Ron, Iron rivets are good... the time I was building my ''Tich'' that is what I used, I had not ''Annealed'' them as my friend Brian suggested, with the result they were a nightmare to put into the countersinks, so heat treating the rivets to soften them is well worth the effort...as for rivet set... I made one out of an old ''Pin Punch'' using a Dremel with fine round stone to cut seat for rivet head... it worked a treat. All the best for now, John.
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Post by baggo on Feb 27, 2007 15:48:35 GMT
Hi Ron,
I left it in the soft state and it seemed ok although there's no reason why you can't harden and temper it. It would probably last longer.
My biggest problem is hitting the end of the rivet and not the frames! I eventually used a piece of steel with a hole in it to protect the frames from the (many) miss-hits ;D
John
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Post by ron on Feb 27, 2007 17:21:58 GMT
Hi John [Baggo] Thanks for the info, along with hacking and filing another good thing learned during an apprenticeship was bashing things accurately with hammers of all sizes , I can almost get a countersunk rivet flush to the point where no filing is necessary-------almost What I was taught when rivetting was lots of light blows rather than a few heavy ones. Hi John [Lancelot] Are you sure it wasn't steel rivets you had, I've never needed to anneal iron rivets, didn't know you could? Ron
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lancelot
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Post by lancelot on Feb 27, 2007 18:15:14 GMT
Hi Ron, good point...I just assumed at the time that they were iron rivets...they were sent with all the other bits, castings e/t/c... in thinking back on it I remember trying to snip some of the rivets with cutters to shorten them...Not a chance...plus the difficulty of putting them down in the c/k, therefore I think you may very well be correct in that they were Steel...thus the advice from my friend re. Annealing. All the best for now, John.
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John Lee
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Post by John Lee on Feb 27, 2007 19:08:11 GMT
Hi John [Baggo] Thanks for the info, along with hacking and filing another good thing learned during an apprenticeship was bashing things accurately with hammers of all sizes , I can almost get a countersunk rivet flush to the point where no filing is necessary-------almost What I was taught when rivetting was lots of light blows rather than a few heavy ones. Hi John [Lancelot] Are you sure it wasn't steel rivets you had, I've never needed to anneal iron rivets, didn't know you could? Ron Ron, You can soften or anneal Iron Rivets. As an ex Aircraft Engineer I have had the dubious pleasure of bashing more rivets than I care to see. Take them to cherry red, then cool them as slowly as you can (sneak them into a hot oven while the boss is out ;D). Keep them in the freezer (hide in the out of date frozen peas at the back until ready for use). This also applies to aircraft grade aluminium alloy solid rivets, but they are unlikely to be used in our application. It does apply to copper rivets but they would be a pretty poor choice in horns. I would disagree with the lots of little hits. Each hit adds to the work hardening in any material that is prone to this. I was taught, push it in with a very slight interference fit, make sure all surfaces are tight with a hollow snap. Whack it down... as I see Ron you know about the straight hammer blow... hard. If its not quite there, do it again. Job complete. There is an interesting tool you can make with a pair of molegrips if you get the rivets in a soft state, but this is restricted by the length of the jaws of the molegrips. Not that any self respecting engineer would admit to owning such a tool Regards, John
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Post by ron on Feb 27, 2007 21:03:12 GMT
Hi John I'm riveting tomorrow, I'll give your big bang method a go, the iron rivets I've got are soft, very easy to shape, probably two good hits and the countesink will be full. I only ever remember bashing steel rivets when I was an apprentice and they were quite large [compared to modelling ones] does steel work harden? Ron
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John Lee
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Post by John Lee on Feb 28, 2007 6:25:33 GMT
does steel work harden? Ron Yes it does Ron, once taken beyond it's elastic limit (as in riveting). There are some processes where this is used to harden mild steels that cannot be hardened in the same way (by heat treatment) as higher carbon steels. John
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Post by Jo on Feb 28, 2007 10:00:17 GMT
Hi Ron,
Do you really have Iron rivets? They are next to impossible to get these days. The suppliers call them Iron but most are steel.
Hopefully you will not have too many to fit, I seem to have done a bit of riveting lately: of the 185 steel rivets for my Clayton trailer, my enthusiasm dropped off after the first 80 odd. Now the old expression "rivetting isn't it" doesn't have the same ring to it.
Jo
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Myford Matt
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Post by Myford Matt on Feb 28, 2007 11:07:23 GMT
Reeves say they do iron rivets - are they really steel?
MM
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Post by Jo on Feb 28, 2007 11:53:56 GMT
MM.
Sadly, yes Reeves rivets are also steel. They will admit it, if you ask.
Jo
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Post by ron on Feb 28, 2007 12:18:49 GMT
How do you tell the difference, and does it matter anyway? Ron
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Post by Jo on Feb 28, 2007 13:35:55 GMT
Hi Ron,
There is a difference in the colour, iron ones tend be darker, blacken then rust, where as the steel ones go straight for the rust.
And when you hit them.....you will know the difference.
Jo
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Post by ron on Feb 28, 2007 15:34:30 GMT
John I've fitted three hornblocks this afternoon, I tried your method and I think I'll stick to the way I was taught, there is much more control and less damage done in the unlikely event of a miss hit, the big bang probably works OK with aluminium rivets but I think from Jo's description I've got steel ones, whatever they are they are quite maleable and easy to shape. Ron
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John Lee
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Post by John Lee on Feb 28, 2007 16:21:31 GMT
Ron,
You have done it, and it's working, so whatever works is, at the end of the day, the right way.
Most of the "hard" biffing was the production of snap heads so the result of a miss was usually a sore thumb rather than job damage. Aircraft grade solid rivets are far from what you might imagine, they are an alloy and are tough little sods, usually about "our" sizes too at 1/8 " or slightly larger.
Which I suppose, although I have never until now given it much thought, is why I use countersunk rivets and form the snap head head on the inside. Doing it the other way round sounds easier, so a lesson learned for me.
You are cracking on a bit with that Simplex!! Nice job.
John
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