ATP* wrote:

wrote in message
...
I've got blisters on my hands from taping 20 holes manually and I have
hundreds left to go!
What machine or tools do I need to tap 5/16th-18 holes in aluminum? I
am using T slotted 1.5" square tubular aluminum for a lot of projects,
ranging from a workshed to a photobooth to a workbench and having to
manually tap the ends of this metal is going to kill me! I'm
specifically using http://www.8020.net/T-Slot-1.asp this stuff. I
bought two specialty taps that are a combination drill/tap bit from
www.mcmaster.com part # 2748A43 At $20 each they are pricy and I've
already busted them both after only about 6 holes each with a hand
drill.

Any help please?

Take a look at
http://www.hitachikoki.com.sg/produc...ls.jsp?pid=115
I think there are similar products from other vendors.

"Special features: Automatic reversing mechanism backs tap out of
threaded hole at high speed"

As in "pull the trigger to tap the hole and don't let go until the
tap has backed out completely."

I'm retired now, but when I was working, I saw one of our people
using something like this at a job site. DANG if we didn't buy some
nice toys!