Running A 12V Drill On 18V

[Onoff]

Mate has an old but heavy duty, 12V Ryobi drill. Originally 12V Nicad.

I was looking into making it run on his DeWalt 18V Li-ion batteries.

The motor is an RS775VF. From what I can make out they have a nominal voltage of 12V but will operate between 6 & 36V.

The switch on the drill says it's good for 20VDC. As I understand it an 18V Li-ion will put out something like 21V. Not sure if this will be an issue?

Lastly what I assume is a voltage regulator. On it printed it says "C50/0 99 48 GDS":

Seems the switch assembly (that incorporates the regulator on a fly lead), is common to the STP 1201, 1401 & 1801 models so 12/14.4 & 18V.

Just tried running it on an 18V Makita battery and it seemed to run quite happily.

3D adaptor time!

 

[HughF]

It will be fine.... that to220 device is a mosfet (gds standing for Gate, Drain and Source). Most of these drills will happily work on 12-24 ish volts. The motors don't care.

 

[Kram]

Replacement 24v 16A rated switches are cheap and generally a good fit, only minor modification required. Ive done it on several 14.4v NiCd drills to run from 25.2v lipo, and the old original switches both blew after about an hours worth of use.
The drill will perform very well with lion but will likely overheat with hard use, they dont put good vents on nicd drills. I have smoked a motor, replacements are cheap.
Nicd drills were mostly basic single speed with rubbish chucks. I see yours is two speed, but generally a modern li-on drill is much nicer to use. I save my nicd for abuse jobs with lots of side load, wire wheels and burrs.

 

[Onoff]

Replacement 24v 16A rated switches

Would you happen to have a link? Something that'd go straight in here would be good!

 

[Kram]

I bought couple of these last time
www.ebay.co.uk/itm/16A-DC-7-2-24V-Electric-Drill-Dustproof-Speed-Control-Push-Button-Trigger-Switch/252682844113