Making a Loose Fitting Rivet

With The

FrankenRiveter

(named after Frankenstein's Monster)

For a special product that I manufacture I needed to have a movable riveted joint between a number of parts. To complicate matters, the rivet head needed to be within a 1/8" recess.

An orbital riveter sounded like the right machine for the task at hand. After getting sticker shock from seeing the prices of new machines, I went looking for a used one in semi-servicable condition.

Living for business gambles, I bought the following machine untested and unseen.

This is the unit that I decided upon purchasing.

It came with the controller.

It turned out that the controller worked but the riveter had leaking gaskets inside and the up/down movement by air pressure was not reliable (jerky movement).

Since it arrived in this crate, problems should not have come as a surprise.

Fortunately, I can fix or devise a work-around for most problems with machinery.

I think the machine was made in France.

I decided to remove the head unit from its base and adapt an old Gorton 3U pantograph base to work with the riveter. After removing lots of rust from the base sitting outside in the weather for years, I was able to get the table to move again as I needed it to do.

Here is the finished FrankenRiveter on its now wheeled base. This outfit is heavy and solid!

I decided to keep the old "War Finish" paint on the Gorton base even though it was in bad shape.

On the vise are the two parts to be test riveted - a brass rod and a square aluminum bar.

These are the items to be riveted so that the brass bar can still move.

Before showing the result I will show a few closeups of the action.

The custom trial tooling was made from oil hardening tool steel. Barely showing here is a 6 degree taper on the tip and its concave end. The tooling merely slips in to the machine and is held in place by an internal magnet. In use the riveter slowly forms the rivet end into a domed mushroom shape without thickening the rod where it passes through the aluminum. Impact riveting will not work for this job.

Using the old Gorton base crank, I raise the items up to the spinning tool. The tool does not merely spin but is at an angle and orbits the very tip (tooling length is critical). With a little pressure the rivet head is formed.

One of the characteristics of this item that I manufacture is the deep recess for the riveted ends. Other makers do not do this.

Here is the finished product - a perfectly formed loose rivet head.

After this initial success, I made 4 new snap peens (final tooling) to plug into the machine as needed for other jobs. The job at hand dictates the shape and size of the tooling.

Here they are after heat treating.

One of the new snap peens in the machine ready to go.

Below can be seen three bars already riveted and one bar end ready for the rivet head to be formed. These bars are only 1/16" in diameter.

Several riveted bars may be seen here.

Though the orbital riveter was designed for air pressure control, it works perfectly for my needs under manual control. The bars shown above were hardened brass. The FrankenRiveter works equally well on stainless steel bar ends. This piece of junk has actually turned out to be a nice tool.