EH Scott Radio Enthusiasts

The Fine Things are Always Hand Made

Hello,

Can anyone recommend a solid rivet tool for replacement of rivets on the Philharmonic PS chassis?

Thank you!

Views: 185

Reply to This

Replies to This Discussion

I've been searching for such a tool for years...not sure anything exists? What kind of tool did they use in the factory? I'm assuming it was some kind of large, bench mounted device...

I have an AM/FM that I'm going to have to re-rivet.  Been thinking of building something that will handle the entire chassis.  Either a mechanical press or a hydraulic press.

Hello-

Commercial riveting in sheet metal, particularly in lower volumes like custom-built radios, is done with machines generically referred to as "C-Squeezes".  They are used extensively in aerospace manufacturing in general and at the specific company I work for.  They are pneumatically operated with a foot pedal, so both hands are free for positioning parts.  A threaded tool holder at the bottom of the C permits up/down adjustment for the lower die.

The smallest ones are hand-held and they can get very large from there.  To buy a new C-Squeeze in a size large enough to accommodate a smallish-Scott chassis will likely cost about $4000+, not including any tooling.  A machine with sufficient clearance in the yoke to reach the center of a Philharmonic chassis will be closer to $10,000+  These numbers are approximations, based on past purchases made by previous employers.

For reference, here is the website for General Pneumatic in Post Falls, ID.  They are a company that builds quality machines. (DISCLOSURE:  I have no personal interest in this company; my opinions are based on machines purchased from them for the companies I have worked for in the past 10 years or so.)

https://www.generalpneumatic.com/heavyduty.htm

The basic technology has not changed in many decades; we are using a few WWII surplus machines in daily production even now at the company where I work, as the largest sizes of machines are, to my knowledge, no longer built new by anyone.  Used machines are undoubtedly available, although I do not have a source.

Tooling for the machines is specific to the type of rivet being used and is also affected by the geometry and clearances of the parts being riveted.  Generally speaking, a cupped lower die holds the head of the rivet (specifically mated to the diameter and profile of the particular rivet), and a flat or flaring style die is used on top to clinch the rivet.   All the Scott rivets I have seen are flared-type, but I cannot state this is always the case.  Rivets being clinched in deep pockets, or with nearby obstacles in the part design, or limited clearances require very specialized tooling.

As such, a considerable portion of tooling used in production is custom designed/machined for the particular parts being riveted.  I imagine Scott had toolmakers employed to design/produce specialized rivet tooling as needed.

Generic tooling examples can be found here:  https://www.yardstore.com/riveting/squeezers/squeeze-sets/new

Riveting at home is difficult at best.  Unless a powered tool (hydraulic or pneumatic) is used, the pressure required will probably necessitate an arbor press.  Keeping the upper and lower dies concentric is essential.  If the machine is powered, a method for limiting the travel of the cylinder is also essential or parts getting crushed is very likely.  The difference between a raw rivet and one that is fully clinched is often 1/16 of an inch or less, particularly on the very small rivets used in radio chassis.

Thanks to all for the great information.

Great info.

I have a few short rivets of the type Scott used. I had limited success - by tapping with a standard hammer on a small ball peen hammer placed on the rivet flair against a metal plate, but access limitations galore. The flair is flattened  but result is not pretty.  Screws and nuts are a lot easier.

I set nickel plated brass hollow rivets by hand using a hammer, rivet set, and aluminum mandrel plus a slew of other tools (levers, etc) for starting the set and for setting rivets in hard to access places.  I occasionally end up with a split flair but seldom have a bad set.

Norman

That's how I did my 16. I have several pieces of aluminum bar that I use on the rivet head.  The aluminum will form a divot that matches the head of the rivet.  I also use an aviation rivet squeezer for rivets that are on the side of the chassis.  Still, I would like to build a large press that will handle the size of the chassis.  I'm not great with a hammer!

Below is a video I made on setting the rivets on my Philharmonic.  It includes doing the brass eyelets and using a bar to reach into places where you can't get a hammer.  I use a cupped set to support the rivet head, and the flaring set to roll it over.  I believe I purchased the heads from here: 

https://www.browntool.com/Listview/tabid/344/CategoryID/439/Level/a...

The set holders I machined myself.  A steel table holds the cupped set, though a wood bench would be fine as long as it is solid.  I did one amp chassis using aluminum to back the head and was not totally happy with it. 

The set heads needed to be turned down to a smaller diameter to provide clearance to sockets, etc. 

It really doesn't take much force with a hammer to roll over brass rivets.  It sounds like I am hitting it harder in the video than I really am. 

All in all, setting the rivets by hand is very fast and easy.  I spent far more time figuring out socket orientation and where ground lugs went. 

https://www.youtube.com/watch?v=svwGcx78hD4&feature=youtu.be

WOW!! Awesome attention to detail!

Great video Scott!

Scott Seickel said:

Below is a video I made on setting the rivets on my Philharmonic.  It includes doing the brass eyelets and using a bar to reach into places where you can't get a hammer.  I use a cupped set to support the rivet head, and the flaring set to roll it over.  I believe I purchased the heads from here: 

https://www.browntool.com/Listview/tabid/344/CategoryID/439/Level/a...

The set holders I machined myself.  A steel table holds the cupped set, though a wood bench would be fine as long as it is solid.  I did one amp chassis using aluminum to back the head and was not totally happy with it. 

The set heads needed to be turned down to a smaller diameter to provide clearance to sockets, etc. 

It really doesn't take much force with a hammer to roll over brass rivets.  It sounds like I am hitting it harder in the video than I really am. 

All in all, setting the rivets by hand is very fast and easy.  I spent far more time figuring out socket orientation and where ground lugs went. 

https://www.youtube.com/watch?v=svwGcx78hD4&feature=youtu.be

Excellent, Scott.  You helped out greatly!

Reply to Discussion

RSS

© 2021   Created by Kent King.   Powered by

Badges  |  Report an Issue  |  Terms of Service