www.KitGuitarsForum.com

I ordered two of these countersinks, this one and one larger, from Lee Valley, on the strength of their description, and was not disappointed. After struggling with traditional countersinks that chatter and require heavy pressure and leave ridged countersinks, these are a joy to use. Super smooth even with an electric drill at low revs, absolutely chatter free, and they leave beautiful smooth countersinks. I'm sure someone else sells something similar, have not tried other brands, don't know who makes them for Lee Valley, but they work. I'm looking forward to using them to bevel bridge pin holes. Bruce W.

Yes, they are a favorite for metalworking. I think Weldon Tool Co first came out with the design years ago, but the patents have long since expired and several companies offer them now. I've bought them from http://mcmaster.com which is an amazing industrial supplier that sells a mind-boggling array of stuff. They sell to "ordinary people " as well as companies and have no minimum order, although I try not to abuse that benefit and try to make my orders at least $25. I've contacted them and they insist they don't care, that they have no minimum order, but it makes ne feel better.

Oh -- sharpening those countersinks. The "correct" way to do it is with cam-operated rotating fixture that puts the proper amount of relief on the face. Since most people probably aren't set up for that, the expedient way to do it is with a small-diameter grinding stone inserted in the hole.

My countersinks are pretty worn out from using them on the wrong materials. Looks like the smaller of the 2 that Lee Valley sells would be the one used for instruments. Do you see any use for the larger one in lutherie? Thanks, Bob

StewMac makes a pin head reamer to do this operation, most likely you already knew that. Got one it works real good or well whatever.

Bruce,

My favorite - impossible to screw up

Ed

Bob - The smaller one is 3/8" in diameter, the larger one 1/2". I have not used either yet for bridge pin holes (soon I hope) but I am inclined to think the larger might be better in the larger diameter pin hole, though either would work. I have used the old single and multi-flute types for so long, never with perfect results, and just did not know these existed (unlike Maine Geezer). They are so easy to control and cut effortlessly even at slow drill speeds. Maybe they are old news, but I am impressed. At about $15 apiece (USD) and free shipping from Lee Valley right now (if you can't find them elsewhere) it's not a huge investment to have both. Bruce W.

Sounds reasonable. Thanks, Bob

If two choices aren't enough, McMaster sells probably a hundred or more variations of these: different diameters, different included angles (60, 82,90, 100 degrees), different steel (regular high-speed steel or cobalt steel), with a pilot, without a pilot, single-ended, double-ended.

Yep, 2 choices is enough for now.. Whenever I look at a machinist supply catalog, my eyes start to glaze over. Wish I was more familiar with all that info, Thanks, Bob