Tools & Fabrication - cutting hole on side of exhaust pipe for wastegate pipe

Sanity check here....I got one of those "hole saw" bits for the drill that is the diameter of mt wastegate pipe I planned to use to cut a hole in my turbo merge for the wastegate. It has the drill bit in the middle to guide it in. Since it says it can be used on mild steel, I assume there is no issue doing it this way? Just want to make sure before I go drilling a hole in my precious merge.

yes it is fine

That's how I used to do it before I got a plasma cutter.

Be careful depending on how strong your drill is. I use a 1/2" drill when using a hole saw for steel. Sometimes the teeth will BITE into the metal. When this happens be prepared. You either have to have a REALLY good hold on that drill. Enough to stop the rotational inertia of that 1/2" drill combined with the torque it is capable of producing... Or, you have to be ready to let go of the button and jump back and let the drill stop on it's own.

It doesn't always do this, but it is best to be prepared just in case it does.

If you are using hole saws, a cordless works best, alot easier on your wrists/arms when it grabs. Cut on LOW speed. I use sheet metal annular cutters but a hole saw will work.

I drill a 1/4" hole, with a small Unibit. I then put a 1/4" transfer punch in the hole saw. [instead of the drill bit.]
This prevents the pilot hole from wallowing out, and allowing the saw to wander OS.
Holes up to 1"+, I use a Unibit.....Greenlee makes them. Not cheap. Available @ LOWES.

http://www.blairequipment.com/Rotabroach_Cutters/rota_cutters.html

they cut through stainless like a hot knife through butter. Did 120 3/8" holes in a bunch of 1/4" a36 plate one day, still cuts the same.

http://www.blairequipment.com/Rotabroach_Cutters/rota_cutters.html



Once you try a rotabroach, you never go back. Unfortunately they are expensive.

Once you try a rotabroach, you never go back. Unfortunately they are expensive.

Hmm...those look interesting...a bit on the pricey side, but I guess it depends how long a typical hole saw lasts for. I bought the quick change + hole saw and it was like $17 from Home Depot...replacement blades were $10-11, so if you can only get a handful of cuts from them before they're worn, it's probably worth the $80+ for a superior solution.