Need idea how to drill a straight 2" hole though a frame

[JeepsAreBuilt]

Im working on a project.. and I am doing a shackle reversal on my CJ. I have located where I want the shackle mount on the frame, it will be a 2" round mount that I need to french into the frame. I need to find a way to drill a straight 2" hole thats gonna keep my mount square to the frame. The frame is boxed, and 2" wide. My idea is to use a 2" hole saw.. and keep a small "L" against the hole saw as I drill it though.

 

[Jim Johnstone]

Anywhere local that rents industrial tools? A magnetic drill would be better for drilling that hole, and they usually run at very low speeds which is what you want for a large diameter hole saw.

 

[trboxman]

Use your 2" hole saw to cut a hole in a piece of 2x4, clamp the 2x4 to your frame where you want your hole, use the hole in the 2x4 as a drill guide for cutting the hole in your frame. Lubricate liberally with light machine oil or cutting fluid.

Personally I'd rent the magnetic drill.

 

[OccupantRJ]

Drill a 1/4 inch hole on each side of the frame, laid out as accurately as you can. Remove the drill from the hole saw arbor and substitute a long 1/4 inch rod as a guide, then hole saw away.

 

[nateplumb]

Mag drill for sure!

 

[rsanter]

Drill a 1/4 inch hole on each side of the frame, laid out as accurately as you can. Remove the drill from the hole saw arbor and substitute a long 1/4 inch rod as a guide, then hole saw away.

This will work

Bob

 

[GarageEnvy]

I've done something similar to the mark on either side suggestion. Drill the pilot hole on one side. Hold the hole saw to the frame and loosen the set screw on the arbor. Holding the hole saw flush on the metal (and stationary) drill the pilot hole through the other side. Here's the catch. You have to have an arbor that allows the pilot drill to come all the way through the arbor and a long pilot bit. Many of the arbors I see now aren't built this way. Also, the arbor needs to have enough area to keep the bit straight and there's still the chance the tip could wander. Good luck.

 

[rocklobster]

Drill one side at a time, resist the temptation to keep drilling through from one side unless you use the guide rod idea.