MTFCA Forum

How does one measure the inside diameter of the steel felloes accurately to within 1/16" in order to purchase the correct style new spokes, without disassembling the wheel first? Thanks, J.R. ('27 Touring)

A difficult challenge!

Since your car is a 1927, does it have split rims and balloon tires? In that case, you have 21" wheels and I believe that the vendors only sell one length spoke, although there are variations in the tenons:

https://www.modeltford.com/item/2800HSB.aspx

https://www.modeltford.com/item/2800HS-500.aspx

https://www.modeltford.com/item/2800HSB-5/8.aspx

If your car has 30 inch wheels, then there can be variation in spoke length and tenon size depending on the original manufacturer. First check to make sure that all of your wheels are the same (some cars have acquired mismatched wheels over the years). With the rim removed, you can easily measure the tenons on your existing spokes to see if they are 1/2 inch or 5/8 inch.

Then, post some pictures of your felloes here, we might be able to tell the manufacturer from the pictures. Also inspect the felloes closely, there might be a manufacturer's mark that is nearly obscured by multiple layers of paint.

Get some glass fiber reinforced packing tape. It doesn't stretch. Carefully apply the tape on the flat part of the inside perimiter of the steel felloe next to the spokes. Cut the ends of the tape so they just touch. Remove tape and re-apply on a flat surface. Measure the length and divide by PI. (3.1416). That will give you the diameter.
The felloe should be clean and not covered with thick or uneven paint which will give incorrect results.
If you are unsure of your measurement accuracy, repeat the process and compare results.

I have used this method for sizing wood felloes to obtain the desired amount of press fit into non demountable steel rims. It works very well, especially since the rims are never perfectly round by themselves so.