- Joined
- Sep 11, 2012
- Messages
- 329
Mr. uglydog;
I don't mean to harp but I don't think you don't quite have the full drift of what is happening yet. A two speed motor requires two magnetic starters, mechanically and electrically interlocked, or two mechanically interlocked manual starters. This in turn requires two overload relays with thermal overload heaters and the necessary pilot controls to operate them in the case of the magnetic starters. The higher speed is rated full horsepower and torque. The lower speed, usually one half the first speed, has only one half the horsepower and something like one third the torque. So at low speed 100% of the time you have one helluva chunk of iron hanging there not doing much with no guts. Just a thought.
Also you mentioned power tapping. Now there is some fun stuff. Tapping holes up to 2K rpm and never harming a tap. I have three heads, all made by Tap-Matic. First two cover sizes "O" to 1/2" and I use in the mill or drill press. The taps used are plain old taps however some taps do work better then others. I only know all this from self teaching and experimenting and reading. When you engage the tap it turns until it is through the hole or meets too much resistance, then a clutch slips, stopping the tap from turning. Lifting the handle reverses the tap and it backs out of the hole. In the mid position the tap does not turn, it only goes in with down pressure and out with up pressure. In tapping through holes, the tap engages and turns, automatically extending out until through the material then reversing and returning. You don't need to move the handle farther.
The third head is an older style I use primarily on the lathe. It taps the hole and the clutch slips when resistance is encountered but you must stop and reverse the lathe to retract the tap. I find that to be no inconvenience on the lathe like I would on the mill or drill.
Hope this helps you understand all this neat stuff better. These heads are expensive but if you hate tapping a bajillion holes like I do, they are well worth it. Besides they are fun to impress people with. I got all three heads off flea bay and was lucky to have $60 or less in each one. The rubber collets used to center the taps are like gold but can be found elsewhere other than Tap-Matic. They are made by Jacobs and have their own series number. Tap-Matic wants over $50 ea---ridiculous.
Have fun and keep piling up the SWARF!
One of my best-us buddies is a retired Firefighter, so I understand.
I don't mean to harp but I don't think you don't quite have the full drift of what is happening yet. A two speed motor requires two magnetic starters, mechanically and electrically interlocked, or two mechanically interlocked manual starters. This in turn requires two overload relays with thermal overload heaters and the necessary pilot controls to operate them in the case of the magnetic starters. The higher speed is rated full horsepower and torque. The lower speed, usually one half the first speed, has only one half the horsepower and something like one third the torque. So at low speed 100% of the time you have one helluva chunk of iron hanging there not doing much with no guts. Just a thought.
Also you mentioned power tapping. Now there is some fun stuff. Tapping holes up to 2K rpm and never harming a tap. I have three heads, all made by Tap-Matic. First two cover sizes "O" to 1/2" and I use in the mill or drill press. The taps used are plain old taps however some taps do work better then others. I only know all this from self teaching and experimenting and reading. When you engage the tap it turns until it is through the hole or meets too much resistance, then a clutch slips, stopping the tap from turning. Lifting the handle reverses the tap and it backs out of the hole. In the mid position the tap does not turn, it only goes in with down pressure and out with up pressure. In tapping through holes, the tap engages and turns, automatically extending out until through the material then reversing and returning. You don't need to move the handle farther.
The third head is an older style I use primarily on the lathe. It taps the hole and the clutch slips when resistance is encountered but you must stop and reverse the lathe to retract the tap. I find that to be no inconvenience on the lathe like I would on the mill or drill.
Hope this helps you understand all this neat stuff better. These heads are expensive but if you hate tapping a bajillion holes like I do, they are well worth it. Besides they are fun to impress people with. I got all three heads off flea bay and was lucky to have $60 or less in each one. The rubber collets used to center the taps are like gold but can be found elsewhere other than Tap-Matic. They are made by Jacobs and have their own series number. Tap-Matic wants over $50 ea---ridiculous.
Have fun and keep piling up the SWARF!
One of my best-us buddies is a retired Firefighter, so I understand.
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