Saturday 20 June 2015

Pimped Dremel

I modded my Dremel tool today. I was having problems with the original battery. Specifically, it was this cheap cordless dremel tool from Maplin for £10

The tool works fine, it's good value. However the battery doesn't last long at all, it's a 9.6v nimh, the charger included with the set doesn't even charge properly - it has no full charge cut-off circuit. This makes damage to the battery possible and potentially dangerous if you leave it switched on too long.

After about 12 months of using it, the batteries barely lasted a minute each for me, and also the charger completely broke. :(

So I was left with a dilemma. Buy and replace using $$$? Or have a go at modding it with an RC lipo battery I already have? So Free!



It was a simple mod to do. The tool unscrews without any issues, I soldered a red & black wire to the correct terminals (they have + & - written to help you), annd connected a XT60 connector.

Et voila:



This mod cost nothing for me, as I already have everything I required. I used a 3s lipo. I was initially slightly concerned about over voltage as the lipo is 11.1v nominal (12.6v max) compared to the original nimh (9.6v nominal - 12v max?? I was guessing a bit).

However, I figure that the tool controls voltage with its potentiometer switch increasing voltage as the dial in increased, so I can test it on a low setting for a while to see if it gets hot. It is noticeable that switch level 5 is now equivalent to 3 using the lipo.

I get much more battery life now, and I also have a small battery alarm to give me voltage readout and beeps when low. Charging takes 25 minutes now, compared to like 6 hours as before.


I think this is a worthwhile mod to a potentially dead item. I have made a $10 dollar tool into a much more expensive model with zero cost. The way I see it is that it is now comparable to the Dremel 8200 but mine has an added low battery alarm + readout, and also that Dremel tool costs almost £150 ($200).

Thanks :)