Skunk Works

Milling Machine Precision Boring

Needing a mount adapter to mount an amateur radio antenna on the push up mast that sits on the hitch insert of my truck, I decided on Lexan plate material for the adapter as seen mounted in the milling machine vise.
In this photo, I am in the process of boring a 2" hole in this Lexan plate that will allow it to sit over the 2" segment of the mast.
I initially opened up the required 2" hole with an slot-drill that quickens the maching process, as although a boring head can bore large precise holes, it takes more time to do.
Still, a boring head is a required accessory for anyone with a machine shop, and preferably in several sizes.
Another example of precise boring head work, is the 1/4 scale Chevy small block V8 engine that I built some years back. The cast aluminum block was bored with this boring head before the cast-iron sleeves were inserted in place.
http://www.jerryclement.ca/MachineShop/Projects-In-Metal/n-6JCfP/i-jLHpc4x

As you can see by the readout of my digital vernier caliper , I need to remove another .oo7" bringing the diameter of the hole to 2", the diameter of the mast segment where this adapter will be located.

The boring head has a analog vernier dial readout divided in 001" on the side of the adjustable precision screw driven dovetailed boring head, that allows me to make the necessary adjustment to the boring head, allowing me to remove the material necessary reaching exactly 2" for a precise sliding fit,

With the two holes required bored in the Lexan plate, the next step will be to shape the outside contour as seen in the photo following this one.....

Click on the photo for a closer look.....

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