Westernize your commiecam!

Westernize your Commiecam, continued... Section 3: Boring the hole and rounding the corners...
	Now that the blank is squared up and layed out, our next step is to bore out a hole in the center of the block for the xlr to sit in. The first step in making any hole is to carefully start the cut with a center drill. A regular drill bit will wander when starting a hole, not so with the center drill.
	With the hole started correctly, simply finish the job with the biggest drill you can get away with and head on over to the lathe to bore the hole out to the required size.
		Okay, here's the tricky part! Because it is square, you must hold the block with a four jaw chuck to accomplish the boring procedure, so that means you MUST use a dial indicator to get your block perfectly centered in the chuck's jaws. Chuck up your indicator so the feeler rides inside the center hole you just drilled in the part. Then slowly turn the four jaw chuck by hand -- you will see the indicator needle deflect high and low if your block is off-center (and it will be!). Keep your jaws loose and carefully adjust them until the part is perfectly centered, a feat which is easier than it sounds, but still something to celebrate when it's done!
		When the part is perfectly centered you should have less than .001 deflection when you turn the chuck by hand. Finally, run the lathe at a very slow speed to confirm your results -- remember, the indicator needle should be dancing back and forth within .001 on your indicator dial. And there should be no vibration from the part spinning. DO NOT try to bring your lathe up to speed without centering the block!!! Now that we have accomplished this all-important goal -- let the boring begin!
		With the lathe at low rpms, use your boring tool to expand the hole to the scribed line for the xlr. Use plenty of cutting oil. I left my block extra long so I wouldn't have to bore all the way through the part. Just get deep enough for the xlr and leave the remaining metal -- we will get rid of it later. If you break through the end of the block you will run into the 4 jaw chuck, which is a bad thing.
		A close up shot of the hole almost completed. Take shallower cuts as you near the end and stop the lathe frequently to check for fit. Again, don't forget to use cutting oil! When the hole is finished, head back to the mill again for more metal sculpting!
		Here is the finished hole but we're not done yet! You may have noticed the 4 pin xlr has four alignment "bumps" that stand proud of it's main circumfrence on the north, south , east and wesr axis. The block must be milled to accomodate them. So here you see two down, two to go!
	Use a corner rounding bit to knock off the sharp corners of the block and give it a nice finished appearance. If any of the sides need to be fly cut again to their final dimensions (matching the xlr), now is the time to do it.
		Here is the almost finished block with freshly radiused corners -- small details like this go a long way to giving your part a more professional, pleasing appearance.
		Scribe marks for the two mounting holes you will drill through the block to fix the xlr to the camera -- but before you drill there is one more step...
		Remember that the block is still too tall for our xlr. So let's head back to the mill again to get rid of the excess...
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