2006-09-27 06:00:51 · 4 answers · asked by mrmustang72 1 in Home & Garden ➔ Do It Yourself (DIY)
The variable speed feature on a hand drill is made with a special kind of device called an SCR or Silicon Controlled Rectifier. Sometimes a more sophisticated SCR called a TRIAC is used. In either case a small voltage controlled by the finger trigger controls a big voltage and current through the SCR.
SCR's get bigger and more expensive based on the current they have to carry. A Drill press draws a lot more current than a hand drill because it has a larger electric motor. You need a much larger SCR to control it. You can build a speed control but it would be expensive. Better to look for a used VSR or variable speed drive on ebay or a local flea market for industrial goods. VSR's are used in industry to control big electric motors and generally are rated by horsepower of the electric motor to be controlled. If you know any electricians they also might know someone who has a used one they might part with for cheap.
You probabl;y need a 1 - 5 hp variable speed AC drive. I' m just guessing how big the motor is on your drill press. You will need to look at the specifications on your motor to match it up with the drive.
Speed control is more than just changing the voltage, the variable speed drive alters current, frequency and voltage to get a smooth linear response to changes in speed.
Best Regards
Adrian Dunevein
2006-09-27 09:11:13 · answer #1 · answered by Adrian D 1 · 0⤊ 0⤋
A drill press generally has a system of pulleys on the top. Changing them will change the chuck speed. I suppose you could get a commercial rheostat though. If you are in a large city there are electrical and electronic stores that deal in used commercial products. Like in Minneapolis there there is a store on Washington Avenue that sells used parts, etc from Honeywell. It used to be called ACME. They had about anything you wanted. You could look for a web site or give them a call, I am sure they would have a toll free number. When I was in the cities I used to buy a lot from them. I like to dabble in electrical and electronic projects.
2006-09-27 07:10:35 · answer #2 · answered by Thomas S 6 · 0⤊ 0⤋
Most drill presses i have seen have a system of pulleys where a belt needs to be change when you want to change the speed.
I remember an electronic unit that came out when i worked selling power tools (few years ago).
This worked on the same principal as the volume control on a stereo, they were not really all that good but may have improver (if you can still get them)
The principal is based on a rotary potentiometer that is able to handle the voltage in your area (110v or 240v)
Please be care-full as you may make your eyes light up if you are unsure what you are doing.
Good luck.
2006-09-27 07:20:23 · answer #3 · answered by Bladerunner (Dave) 5 · 0⤊ 0⤋
It generally works through adjusting pulley diameter inside the cabinet. To my knowledge there isn't an easy way but there are pulleys available with a variety of diameters on one sleeve. If one of those will fit inside your drill press cabinet..they can change speeds by moving the belt to a different diameter pully
2006-09-30 03:24:59 · answer #4 · answered by Duke D 3 · 0⤊ 0⤋