rainbow fin box 1970s

General Discussion
1

I have a san Francisco surf board company  9’6" board that I knocked the center fin off and broke the box.It appears due to tail thickness a shallow 10 1/2" fin box was used  its about 7/8" deep. Anyone know if these are still out there anywhere? I think I can grind a standard one down but it will compromise the strength I’m sure. It’s a rainbow box board is maybe a 1974.

Thanks for any help .

2

I do not recall Rainbow ever making boxes, just fins. If the board is a single fin from 1974, it has a Fins Unlimited box.

3

Your right , I’m an idiot. Same question though 

4

probably just a ground down Bahne/FU box…taking off 1/8 inch won’t hurt.