In my 25 touring there are 2 different size tacks in the door panels
The one on the left is what came out of the door the one on the right is the closest I could find to replace it.
the one on the Right came out of the door the one on the left is the closest modern I can find. the big ones have a head diameter of 7/16" and have a higher dome than the modern ones
The smaller ones have a 3/8 diameter head and the head is flat.
My question is which tack did the car come with?
I don't know about the rest of you, but our 1915 Roadster sheds these tacks on a regular basis. Knock on wood,so far so good, none have had a chance to get up close and personal with a tire yet.
Those are called upholstery nails, not tacks! No one makes the exact size upholstery nail any more, But, Witmer Coach Shop in New Holland, Pa. has the closest I've been able to find. They are 1/32" larger diameter than the originals, which are exactly 3/8". Most of the ones you find today are 7/16. Your answer is 3/8.
Jay, our T's must be related. I took out a bunch, if not all, they kept falling out of the hip panels. I to do not want a puncher a tire.
Maybe try putting a dab of black RTV on the back of each upholstery nail when driving it in?
Mark, I have done that a couple of times when I had an upholstery button come off. I could not access the back side to reattach them so your method worked great!