Description of π HHIP 5000 0020 Center Drill No 1 No 5: Precision Tool for Accurate Hole Drilling
5 Piece Plain Style Set!. Sizes #1~ #5!. Made of high speed steel and ground. 60Β° countersink angle fits all standard centers. Used for centering work ends, where the work piece is to be revolved on machine centers.
I am happy with the purchase. I've run them through epoxy, wood, composites, aluminum, damask, and stainless steel with no problems. A good buy for the price and I will order again if they ever dull or break like all tools.
I usually get really good quality from HHIP materials. However, this was a complete disappointment. I estimate I drilled about 10-11 holes in the center before each side wore out. Now they sit unused because a frozen banana keeps the edge longer.
Disappointed: I was looking forward to this because M42 cobalt center drill sets are not easy to find. I tried using size #1 first but it seemed like it would be off center. I took it out of the chuck, examined the end and was surprised to find that the sharpening angles were wrong. On one side, the angle has been found to be correct, and the left side is tilted down. On the other hand, the left side was higher than the right. I checked the other end and it was the same. I checked the rest ofβ¦