device to slow drill speed

[pcatterall]

I only have a standard mains type drill aboard but recognise the need to be able to drill metal at slower speeds. My current drill (and most of the ones I have had) does have a variable speed control but it doesn't seem to function well. Is there a device that I plug into with a more sensitive control?

 

[VicS]

I only have a standard mains type drill aboard but recognise the need to be able to drill metal at slower speeds. My current drill (and most of the ones I have had) does have a variable speed control but it doesn't seem to function well. Is there a device that I plug into with a more sensitive control?

This sort of thing. Like a high power ( 1000 W) dimmer. Had it for donkey's years. Don't even remember where I "borrowed" it from.

 

[vyv_cox]

Does it deliver full power at reduced voltage (or whatever means it uses)?

 

[jakeroyd]

This sort of thing?
(Could not find a modern equivalent)
https://img1.etsystatic.com/044/0/6795537/il_570xN.564229511_1tpx.jpg

 

[VicS]

Does it deliver full power at reduced voltage (or whatever means it uses)?

No. I guess it's a triac based device. Looked inside but cannot see very much. Poorly made IMO.

I used it a few times when using an old drill for polishing but eventually decided the slow speed gear on the drill was about right on its own
Now have a variable speed polishing machine anyway

 

[VicS]

This sort of thing?
(Could not find a modern equivalent)

Similar to this, but this is just a 4:1 speed reducer. Dont think I have ever used it. I think it was my father's

 

[rogerthebodger]

Does it deliver full power at reduced voltage (or whatever means it uses)?

It will reduce the power of the drill but the most important downside is the reduced cooling of the motor due to the slower speed of the cooling fan. This also of cause reduces the duty cycle of the drill which even at full speed is no more than 10% at best

Drilling the odd hole may not be an issue but on power tools like circular saws and die grinders it is a problem

When I started polishing stainless steel I used to use a die variable speed die grinder on it slowest speed and I burned it out in 3 minutes of operation due to the reduced cooling air flow.

Geared down machined are far better due to increased torque and the cooling air flow from the higher speed motor.

VicS device is the same as most electrically variable speed tool use being triac based device