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Marco Tahtaras · 06-26-2010, 10:06 PM

For the record, I saw a 1930 (silent) Ford film years ago showing a frame being riveted together. It was very dark footage except for the cherry red rivets! The rivets were indeed squeezed. the riveter was a large device suspended from above so one man could swivel it into place and set the rivet. A second man simply transferred the red hot rivet from what looked like a coal bed to the hole that was to be riveted.

The following is the text of something I've posted several times over the last ten+ years. Other riveting suggestions that have been posted just don't do the job correctly. I've tried them all!!!

Riveting ---

As with many tasks, More time is invested in setting up than performing the actual task.

The cross members were riveted with 1/4" rivets. You'll find that the the holes to be riveted measure almost 5/16" (and were intended to be). The shank of the rivet MUST swell to fill the hole to be effective over the long term. For this reason it is difficult if not impossible to tighten a loose rivet. You can tighten the "set", but not swell the center.

For bucking we start with a ready made 8" bucking bar with the proper recess for the rivet head. We then cut the bar short enough to fit within the frame rail. This short bar is then welded along the side to a heavy piece of steel forming an off-set bar that extends around the edge of the rail. The bucking bar should be at least 3-4 lb.., but 5 lb.. is better.

For setting the rivet we use an air chisel or air hammer. I've been told they are commonly available in short stroke and long stroke versions and I use the long stroke or long barrel version. I think way too much is made of the type of air hammer as the rivets swell like butter when the shank is properly heated. The setting tool for the air hammer is matched to the rivet size similar to the bucking bar.

The riveting requires two people in almost all cases. The first person holds the rivet by the head with pliers while the second person heats the rivet with a torch. The rivets are heated red from the middle first, then towards the outer end.

Next, while the first person slips the rivet into the hole and backs it with the bucking tool, the second person sets down the torch, picks up the air hammer and proceeds to rivet.

The result is a rivet that completely fills the hole as it should. The process requires approximate 30 seconds per rivet.

Additional Notes:

1. If you attempt to back the rivet with a stationary object it will actually manage to walk back some appearing loose on the head side.

2. Anything functional can be used a bucking bar, but the head of the rivet WILL take the shape of the tool.

3. As a general rule the un-set rivet should extend through the hole 1-1/2 times the diameter of the rivet, i.e., 3/8" for a 1/4" diameter rivet. However our frame rivet holes are oversized by design requiring a little extra length to completely fill the hole.

4. Mild steel round head rivets up to 1/4" are readily available at many hardware stores.

Prior to assembling the frame for my Roadster we heated rivets in place with acceptable results. Since my frame was being completely assembled from parts I decided I wanted a good quality sealer applied to all the parts prior to assembly to prevent future corrosion in the joints. I didn't want to burn the sealer off the frame at the rivets, so we attempted the method described above. It worked so much better that I will never go back to heating the rivets in place! Once the frame was assembled with bolts and confirmed to be absolutely symmetrical, It took approximately an hour to install all seventy rivets.

Since most people won't go through the riveting process more than once, it makes sense to acquire or make the tools as a group or club project.

Links:

Big Flats Rivet Link: http://www.bigflatsrivet.com/

My frame project: http://www.abarnyard.com/roadster/frame.htm

06-26-2010, 10:06 PM	#5
Marco Tahtaras Senior Member Join Date: May 2010 Posts: 3,099	Re: Bucking frame rivets For the record, I saw a 1930 (silent) Ford film years ago showing a frame being riveted together. It was very dark footage except for the cherry red rivets! The rivets were indeed squeezed. the riveter was a large device suspended from above so one man could swivel it into place and set the rivet. A second man simply transferred the red hot rivet from what looked like a coal bed to the hole that was to be riveted. The following is the text of something I've posted several times over the last ten+ years. Other riveting suggestions that have been posted just don't do the job correctly. I've tried them all!!! Riveting --- As with many tasks, More time is invested in setting up than performing the actual task. The cross members were riveted with 1/4" rivets. You'll find that the the holes to be riveted measure almost 5/16" (and were intended to be). The shank of the rivet MUST swell to fill the hole to be effective over the long term. For this reason it is difficult if not impossible to tighten a loose rivet. You can tighten the "set", but not swell the center. For bucking we start with a ready made 8" bucking bar with the proper recess for the rivet head. We then cut the bar short enough to fit within the frame rail. This short bar is then welded along the side to a heavy piece of steel forming an off-set bar that extends around the edge of the rail. The bucking bar should be at least 3-4 lb.., but 5 lb.. is better. For setting the rivet we use an air chisel or air hammer. I've been told they are commonly available in short stroke and long stroke versions and I use the long stroke or long barrel version. I think way too much is made of the type of air hammer as the rivets swell like butter when the shank is properly heated. The setting tool for the air hammer is matched to the rivet size similar to the bucking bar. The riveting requires two people in almost all cases. The first person holds the rivet by the head with pliers while the second person heats the rivet with a torch. The rivets are heated red from the middle first, then towards the outer end. Next, while the first person slips the rivet into the hole and backs it with the bucking tool, the second person sets down the torch, picks up the air hammer and proceeds to rivet. The result is a rivet that completely fills the hole as it should. The process requires approximate 30 seconds per rivet. Additional Notes: 1. If you attempt to back the rivet with a stationary object it will actually manage to walk back some appearing loose on the head side. 2. Anything functional can be used a bucking bar, but the head of the rivet WILL take the shape of the tool. 3. As a general rule the un-set rivet should extend through the hole 1-1/2 times the diameter of the rivet, i.e., 3/8" for a 1/4" diameter rivet. However our frame rivet holes are oversized by design requiring a little extra length to completely fill the hole. 4. Mild steel round head rivets up to 1/4" are readily available at many hardware stores. Prior to assembling the frame for my Roadster we heated rivets in place with acceptable results. Since my frame was being completely assembled from parts I decided I wanted a good quality sealer applied to all the parts prior to assembly to prevent future corrosion in the joints. I didn't want to burn the sealer off the frame at the rivets, so we attempted the method described above. It worked so much better that I will never go back to heating the rivets in place! Once the frame was assembled with bolts and confirmed to be absolutely symmetrical, It took approximately an hour to install all seventy rivets. Since most people won't go through the riveting process more than once, it makes sense to acquire or make the tools as a group or club project. Links: Big Flats Rivet Link: http://www.bigflatsrivet.com/ My frame project: http://www.abarnyard.com/roadster/frame.htm __________________ http://www.abarnyard.com/ Last edited by Marco Tahtaras; 09-22-2012 at 05:03 PM.