[Rick6a]

A Unibit is great for generating holes up to 3/4" but is there an economical tool that will produce holes in thin material in the 1"-1-1/2" range? The larger Unibits require a larger drill chuck than my drill motors are fitted with. I want to install some firewall pass-throughs that require holes 1.10" in dia. What tools are available that will produce quality holes in the ranges I seek?

 

[Vern]

Hole tools

See the aviation department cleverly disguised as electrical tools at Home Depot or Lowes. Most electrical supply houses also carry these. There are various size tools used by electricians. Cheap? No!

 

[DaX]

Get a knockout punch set - Greenlee makes a good one.

 

[Gary Bricker]

Gary Bricker

Check with Avery. They have a great hole cutter set that is that large and does a beautiful job on stainless

 

[alpinelakespilot2000]

I used a regular $10 bimetal hole saw to cut my heater box hole through the stainless steel firewall with no problem--left a very clean hole. Just back it up with a piece of wood or something while you're cutting it.