Iím working on my í26 Runabout and have questions about the 3/16" body rivets.
1) Were the rivets for the trunk floor inserted from the bottom? (Waffle pattern visible on top side)
2) Do the rivets under the seat get inserted from the top?
3) Do the rivets in the seat back get inserted with the heads in the trunk side?
The previous owner of the car made many non-correct improvements including using a very thick sheet of steel for the floors and he removed the previous fasteners. I now have the correct panels and Iím trying to do this right the first time.
In a conversation with Royce Peterson, he recommended a 3X aircraft riveter to replace the missing rivets in my car. He also recommended looking on eBay for good used but I elected to buy a new US made ACAT since my son assured me heíll let me work on his Model A someday when I get good at riveting.
Here is my first attempt with two scrap pieces of steel bucked on my vise anvil. I was delighted to see that using a riveter beats trying to do this with a Harbor Freight air chisel.
The waffle tool came from one of our well known parts suppliers as did the floor rivets.
In regards to question 1, Iím guessing the rivets were bucked from underneath the car because I see more room for a bucking bar than I do for the nose of the riveter since the waffle tool is fairly short. Also the holes in the subframe are larger leading me to believe the large head of the rivet would be better suited on that side.
Does anyone have restoration photos showing how the rivets are installed?
I do not have a 26 to look at but someplace I just read that the poster was getting a better job when he turned the air pressure down to 60 when using his HF rivet gun. Something to think about, when the car was built the subframe/foundation was built then the rest built up from there. What is now hard to get to would have been easy to get to then.
I used the recommended 90 psi with the 3X and got excellent results. The shorter stroke air chisel bounced around and didn't work as well. The photo I show above is equivalent to what I'm seeing on original Model As.
The subframe rails are a deep U cross section. They were narrow prior to other riveting. I think the factory tool would have been difficult to apply in those areas so I suspect a thin bucking bar was used there instead.
I am going to go with; 1928/29 Model A's had the round rivet head on the inside and waffle pattern on the underside. The Model A sub floor was built upside down and I would guess it would have been a work flow carry over from the Model T.