Converted 9 Bolt Horn

[Robert Luland]

Why try and rivet it. I'm willing to bet Delco had a 5HP minimum hydraulic orbital riveter to do this. You are not going to duplicate that but there are alternatives. Tig weld that puppy, put it in a rotary on the mill and just pick what end mill you want to shape the weld. We do it in our shop all the time on old stuff and you would be hard pressed to ever know it wasn't original. Nobody will ever see an extra .03125 of material for strength. Bob L

[Old Ugly 40]

Why try and rivet it. I'm willing to bet Delco had a 5HP minimum hydraulic orbital riveter to do this. You are not going to duplicate that but there are alternatives. Tig weld that puppy, put it in a rotary on the mill and just pick what end mill you want to shape the weld. We do it in our shop all the time on old stuff and you would be hard pressed to ever know it wasn't original. Nobody will ever see an extra .03125 of material for strength. Bob L

Hi Robert,
I appreciate your input but I have to ask, have you actually performed this procedure on one of these horns? I do not have any of the equipment that you mention nor do I know anything about it. I would be concerned that the heat from any welding may screw up the windings inside the horn. Fell free to correct me if I'm wrong.
I wish I knew how to post a link to the old thread "1939 Delco horn for knucklehead. As I mentioned before, the pic that jorrow posted, of what appears to be an original
9 bolt horn, the washer appears to be fairly thick so why would one want to take it apart and remove the bracket?
I have already had the bracket removed on a lathe. I will try to post pic in my next post.
Again, thank you for your input, looking forward to more. Always learning.
Rod
AMCA#25781

[Robert Luland]

Rod, I see your point. I haven't had one of these horns a part in my hands in years. I was referring to riveting in general. Now ya got my brain cells spiked. Gonna pull a horn off the shelf today and look in side. I see these things for sale all the time with the bracket snapped off right at the center. Be nice to come up with a way of fixing them fast and cheap. Bob L

[Rubone]

Mutt (Charles Hallam) in Texas does restoration on them. Just ask him.

[Old Ugly 40]

Hi again.
So I had the bracket taken off in a lathe, cost $20.00.
The 3 holes that need to be added hold the face on so with the horn terminals at 3 o'clock the top hole for the face is at 12 o'clock mid center between the top two holes in the horn body. I put small pieces of masking tape on the body in approximately where the new holes should be. Then I cut a strip of heavy paper in the shape of the bolt lip on the body and trimmed to length between the inside edges of the top two bolt holes. Folded the paper in half to find center, marked it, poked a small hole in it, lined the paper up between the top holes again and marked center line on the masking tape. Set the horn face on and centered the top hole on mark on the masking tape. With a sharp pen I traced around the three square holes in the horn face. Then used a small ruler and drew an X across to find centers and center punched and drilled. Pretty simple.

[Old Ugly 40]

Back again.
I then bolted the other two pieces on and drilled then squared holes with a small three cornered file. Done.





Thanks for the help guys.
Bye for now.
Rod
AMCA#25781