The flange is now hardened - bad for drilling, and bad for the long life of
the header, to some extent. You need to anneal it, which you do by heating
to dull red, keep it at that heat for a minute or so, and then arrange to
very slowly cool it, which I do by burying it in dry sand. let it cool,
then try to drill.
Brian
At 07:51 PM 7/2/99 -0400, you wrote:
>I'm hoping one of you mechanical-types can help me out. I recently had a
>steel exhaust manifold flange welded, and now I'm trying to redrill the
>hole for the stud. I can't find any drill bits that will cut through the
>welded steel. I've tried regular high speed drill bits, titanium-coated,
>cobalt, and most of them won't even touch it. Yes, I'm using cutting oil.
>I've managed to get about 1/8" through, but the more I try, the less effect
>I seem to have. Any ideas?
>
>Calvin Krug
>trying to rebuild my MGB
>
>
>
Brian Evans
Director, Global Sales
UUNET, An MCI WorldCom Company
|