Variable Speed Adaptor

[NickWelford]

Two questions...

Does anyone remember the old fashioned adaptor which one used for varying the speed of a (usually) Black and Decker single speed drill (remember them?) - it sat between the drill and the power and had a, presumably, rheostat to cut the power and slow the drill.

Following on from that - I have a single speed Delta scroll saw - should I be able to find one, can I use same to cut the speed on the s/saw?

 

[tigerturnings]

Hi Nick,

I still have one of those drill speed controllers, must have been given it at some point a few years ago. It is not a simple rheostat, but rather it works in very much the same way as a dimmer switch. For each half-cycle of the mains, it turns on its output a short time after that half cycle begins, so less power in total is delivered to the tool. By varying the time before it switches on the output, it is possible to vary the speed of an attached universal (brushed) motor.

As for whether your scroll saw will work with such a controller, it depends on what type of motor it has. If it's an induction motor then connecting it to a speed controller like we're talking about here would probably damage one or both of the motor and controller, and would certainly not result in a reliable variable speed drive.

If it's a universal motor (with brushes) then it should work, assuming that the speed controller is adequately rated for the motor's power requirements.

I'm not familiar with your particular saw, but if I had to guess, I'd say it's more likely to be an induction motor and therefore unlikely to work.

Cheers

Neil

 

[DaveL]

Does anyone remember the old fashioned adaptor which one used for varying the speed of a (usually) Black and Decker single speed drill (remember them?) - it sat between the drill and the power and had a, presumably, rheostat to cut the power and slow the drill.

Remember? Well yes, I made one as an apprentice project in the early seventies, I still have it somewhere but the lead needs replacing. :?

Following on from that - I have a single speed Delta scroll saw - should I be able to find one, can I use same to cut the speed on the s/saw?

As Neil has said they will only work for universal motors and the scroll saw is most likely to have an induction motor, so no.

 

[NickWelford]

Thanks Guys, Looks like I'll stick with the current one until I find a real need for a slower speed...

 

[scroller frank]

Hi Nick,
no ,it dosn't work! i have tried it on my Delta saw ,
but i found a variable speed Delta on ebay , £35.00 and only 7 miles away at Newark! , so keep an eye on ebay!
all the best ,--------scroller frank----------