Gary, thanks for posting your review.
I started using this method about 4 years ago !! I square the barrels by cutting the excess in the band saw, and then the disk sander, until I see the edge of the tube. This tool then trues up the barrel. I also use it after the barrels are turned, if necessary, to make a good fit.
Of course, I had to make the gizmo myself, and it was kind of crude. Then I had the bright idea of making a nice machined one. It worked for me, but the cost would have been too high for others to buy from me. It had to be turned from 1" solid steel bar, which is not only expensive, but requires a lot of machining.
This version is made from material that I can get a lot cheaper. As you can see, the main part is a common BOLT. The face of the bolt is then trued up, and drilled and tapped right on the lathe, so the shaft is at a true 90 degree angle to the face. This is the crucial part. The shaft is made from a high grade commercial hex cap bolt which I modified, and it fits the 7 mm tube like a glove.
I have a few of the main part, and materials to make a few more shafts. The other part is the 3/16" punch shown in the pics, which I also made from drill rod. It is not intended to cut through the sandpaper, rather it scores the backing so you can tear off the little disk in the middle. Otherwise it will not last very long. By the way, the punch can be sharpened several times with medium grit emery paper, by hand!
I intend to make this available soon. No price yet, but as usual, I want to make my tools affordable. If you email me I will put you in a waiting list.
Thanks again, you guys, for your nice comments !!!
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