Tapping 4130

[mhorowit]

I'm tapping some 4130 tubing for the horizontal stabilizer bumper that fits on the tailpost. This is miserable work. Maybe my tap is worn.

Is there a secret to taping 4130? - Mike

[Pearson]

Re: Tapping 4130

Use a light oil and make sure you have the correct size hole for the threads you are cutting.

[Hank Jarrett]

Re: Tapping 4130

Like tha man said, if you are having that much trouble there is something wrong. A sharp tap and some tap lube with the right size pilot should cut like butter.
Hank

[Pearson]

Re: Tapping 4130

Mike,

What size and thread are you trying to tap?

[mhorowit]

Re: Tapping 4130

Mike,

What size and thread are you trying to tap?

5/16 NF 24 tpi. I done it but it was rough going - Mike

[Carrieve]

Re: Tapping 4130

Make sure that you have a starting tap. That is one in which the end is tapered. It makes getting started so much easier. Once you get started you can go to a bottoming tap if you have to go all the way to the bottom of the hole. A bottoming tap has the blunt end.

[Pearson]

Re: Tapping 4130

Mike,

If you need to tap a hole make sure you have the correct size hole for the tap you are using. I tried to attach a chart that shows the different size holes for each tap, but the file format was not accepted.

You can do a Google search for "drill tap chart" and see what I am talking about. For a 5/16X24 thread you needed an I letter drill. If you have a chance to go by an industrial supply, they have charts they will often give away.

[Forrest Barber]

Re: Tapping 4130

Was the area heated for welding and cooled too quickly... makes it kind of hard!

[mhorowit]

Re: Tapping 4130

Was the area heated for welding and cooled too quickly... makes it kind of hard!

Unheated; although I was going to ask if my work would have been easier if I had annealed it. - Mike