M.L. Toys
M.L. Toys
HobbyMasters M.L. Toys
for 12v vehicles that NEED to be upgraded to 18v
By misterG
Have Barbie 12V 9.5 A/h PW and want to use Ryobi VS switch(rated 9-20 amps) for accelerator.

Question: How does one determine what switch load rating is required for a given battery voltage/amperage?

If if converted the barbie to an 18v system what switch rating would I need?

Brand new to posting to forums so let me know if I posted in the appropriate forum/section.

Mike G

By misterG
Answer: Use OHM's law to determine load.

Temporarily hook up Ryobi VS drill switch to PW and do an actual test to measure heat in motors, wires, and switch heat sink. Run drill switch for several minutes with zero wheel load. RESULTS: No heat.

Conclusion: Probably ok to use Ryobi 20 amp VS drill switch to controll speed of a Barbie 12 Volt PW.


I just fried two ryobi drill switches attempting this mod on an otherwise stock 12v Barbie Jeep :x . Does anyone have a proper wiring diagram that worked for them when making this mod? I am just trying to give my kids some fine low speed control but now I am out $26 for the replacement switch. (The first switch was harvested from the donor drill so that was a freebie). Is there some issue using this drill switch with the two wheel motors in low speed that makes the internal chip (transistor?) burn up before the wheels even turn? I had not tried it in high -- just reverse. I cut the black negative wire on the jeep, and connected the battery white and black to positive and negative on the drill switch. Then I connected the black wire going to the jeep to the black wire on the motor end of the switch. And the red wire from the jeep to the red wire on the motor terminal on the switch. Just like in the ryobi drill, from what I could see. I can't figure out what went wrong, and it is driving me nuts because these things are so darn simple.
Go big or go home. You may be pulling to much of a load for the PWM switch to handle.

I added a larger heatsink and used a Milwaukee 23-66-1779 36v 25 amp rated switch. I also rewired the 14ga wire to 10ga. This was to support 775 motors running 24V (single speed) with 7R 19T Gearboxes (cleaned and re-lubed with Superlube 21030 Grease
36v switch 23-66-1779 .jpg
36v switch 23-66-1779 .jpg (140.36 KiB) Viewed 1817 times
24v PWM Switch Milwaukee 23-6601779.jpg
24v PWM Switch Milwaukee 23-6601779.jpg (67.73 KiB) Viewed 1817 times
I also stole this wiring layout an made it my own (added some notes)!

I see alot of users here just but the premade gear motor stage combos but the only part I needed for this form them was their $11 7R adaptor. (just wished they were machined to match the openings on the 775 motors) Hint Hint!

Now where they will shine is the Milwaukee PWM switch adapter or a kit as that was the hardest part of this whole thing.
Arctic Cat Wiring.png
Arctic Cat Wiring.png (54.45 KiB) Viewed 1817 times

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