[gd.marsh]

I've started a new thread on this because I don't want to hijack the thread where I was asked to share some more information about this tool.

What I have done is convert a small Rockwell Drill Press to a power tapping machine. I got the idea from the following thread, but decided to add power to the mix.

http://homepage3.nifty.com/amigos/ta...ng_stand-e.htm

I determined to tackle the issues of: Torque, Speed Control, Reversing, Compression/Extension, & Tap holding.

Short of disassembling my machine, I can't show any pictures of the compression/extension set-up but I can say (at least on the Rockwell) it was a simple matter of taking the spindle apart and adding a couple springs to the mix. There was no machining necessary for this to be done.

I happened to have a 12v 1/4hp DC motor laying around with an inexpensive speed control that I had purchased at a yard sale. I also had a transformer that was reclaimed out of an old battery charger. I purchased an Antec rectifier/capacitor unit from ebay and now had: Power Supply, Speed Control & Motor. Reversing was easily handled with 12v relays and a two-way foot switch found also on ebay.

For more torque, I knew that Rockwell had offered some of their drill presses in both high speed & low speed models. The low speed model was identical to the high except for a larger step pulley on the spindle. Another quick search on the bay also turned up a large pulley and that handled the torque issue.

I wrestled for a while with tap holding .. Thinking I would have to grip the tap at the square shank to keep it from spinning I first tried one of the Irwin tap adapters, but didn't care for the sloppiness it introduced. One day needing to tap several small holes I decided to just install a new chuck I had on the shelf and see if I could get my job done. It worked perfectly! .. In fact I've since tapped holes up to 1/2-20 in 3/16 steel angle with this set up.

I can not provide a wiring schematic because I am not trained in Electrical or Electronics and I will not be responsible for anyone's results other than my own .. Truthfully, I just bungle my way through this stuff with trial & error .. (read that as releasing the magic smoke now & then) I'm sure there are well qualified individuals on the zone that could provide a wiring schematic for PROPERLY accomplishing what I've done here.

[knudsen]

Hey that's pretty cool. Rohm chucks rock!

[rowbare]

Very nice! Thanks for sharing this.

bob