Frame hole size for 5/16" self-tapping brake line clamp bolts?

[Robert W.]

Hi, I'm about to start drilling holes in my new Vette Products frame and I want to be sure I don't mess it up! I'm planning on drilling 1/4" holes and "starting" a 5/16-24 tap in each hole to clean up the alignment. Does this make sense?

[Gene M.]

Re: Frame hole size for 5/16" self-tapping brake line clamp bolts?

Use care in doing so because there is only about one thread pitch engagement in the frame. Use a slightly smaller tap drill than spec’d for a 5/16-24. The results will be a tighter class fit of the threads since the sheet metal is so thin. I’d also say to only run the tap in till just into the end of the lead taper.

[Dick W.]

Re: Frame hole size for 5/16" self-tapping brake line clamp bolts?

Drill the holes 19/64s and let the self tapping bolt cut the threads

[Joe L.]

Re: Frame hole size for 5/16" self-tapping brake line clamp bolts?

Drill the holes 19/64s and let the self tapping bolt cut the threads

Dick----


Yup!

[Robert W.]

Re: Frame hole size for 5/16" self-tapping brake line clamp bolts?

Thanks! -Bob