Heater Vents

Getting back to my dashboard mounted heater vents, I have the flat panels welded in now on both sides of the dash, and it is time to drill the 2-1/2 inch holes for the vents.

I did this using a bi-metal hole saw.  First I used the vent to draw a circle where I want to cut the hole, and then used a ruler to find the center point. Then I drilled a 1/4 inch hole for the saw to center on. When using a large hole saw on metal, you need a lot of torque, and a slow cutting speed. Sounds like a job for the big drill press.

Setting this up on the drill press was a bit of a challenge. The "other" end of the dash is being held up with a telescoping stand that I happened to have, and the piece of wood in the vice (which just happened to be in the right spot) prevents the saw from spinning the entire dash panel.

On the drill press end, the dash is clamped down to the table between two blocks of wood. This was a little tricky to get setup, but it got the job done.

This is looking at the two cut holes from the back side of the dash. I had intended to have 1/8 inch or more of clean metal around each hole, but the welds are coming right up to the edge of the hole in places.

With some careful work with my angle die grinder (the most-used tool on my bench lately) and some sanding disks, I was able to grind the weld down almost flat.

I am a little paranoid of cutting too deep. I would rather leave a few small bumps than to do to much and create thin spots. This will be a good enough surface for the vent duct to mount against.

There is still a lot to do on this dash board, but these vents are going to look trick, in a "yeah, it was just meant to be that way" sort of a way.