I make a variety of items out of old aluminum scuba tanks. They are typically 6061 aluminum and 1/2" wall thickness. They are 7-1/4" in diameter.
I am trying to drill holes that are about 1-1/8" to 1-1/4" in diameter. The largest twist drill bit I had was 1". I bought a new Lenox 1-1/4" hole saw bit.
While the regular bit did fine making the hole, the hole saw bit gummed up within the first 1/8" of the cut. I then had to stop and clean out the teeth every minute or less. That material that clogged up the teeth ended up making the hole larger than wanted and was relatively rough. By the time I sand that smooth it will be quite a bit larger than I want and take up too much of my time.
I am using my Bridgeport mill and going at about 800 RPM's based off what I could find online.
Would a regular twist Deming bit be better to make the holes or should I switch to an anular cutter?
Pics for reference. The hole on the right is from the hole saw and the hole on top is from the regular deming twist drill bit.
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I am trying to drill holes that are about 1-1/8" to 1-1/4" in diameter. The largest twist drill bit I had was 1". I bought a new Lenox 1-1/4" hole saw bit.
While the regular bit did fine making the hole, the hole saw bit gummed up within the first 1/8" of the cut. I then had to stop and clean out the teeth every minute or less. That material that clogged up the teeth ended up making the hole larger than wanted and was relatively rough. By the time I sand that smooth it will be quite a bit larger than I want and take up too much of my time.
I am using my Bridgeport mill and going at about 800 RPM's based off what I could find online.
Would a regular twist Deming bit be better to make the holes or should I switch to an anular cutter?
Pics for reference. The hole on the right is from the hole saw and the hole on top is from the regular deming twist drill bit.
