Dremel fuse and control

dremel amperage

Seems my CNC controller has a 10 amp relay for spindle control.

I want to connect my dremel to it so it will come off and on automatically. I’m assuming that should be fine because on the Dremel site the most similar dremel specifications shows just over 1 amp.

I also want to add a fuse to the mix so I don’t fry my dremel if it stalls.

Anybody know what a good fuse size to use would be?

My first guess would be about 2 amps. I’d guess if you stall the dremel the amperage would probably go above it’s manufacturer amperage claim.

Anybody ever put a fuse to protect your dremel?

Dremel Cooked


I was making some parts using my dremel as a small spindle and I managed to stall it.

What happened when I released the load was the dremel spooled up very weakly. It ran very weak for about 10 seconds then spooled down.

I was concerned that was the last time it would ever tun.

I immediately disassembled it and did an inspection. No visual damage on any of the armature or other windings.

Further inspection revealed that one brush was seized. How strange. I guess it may have arced and heated. I filed the brush till it could move freely and reassembled.

The motor now runs even better. Way more rpm. The brush may have been marginal. Thankfully as it broke the connection before the motor completely fried.

I suppose I need a fuse for the dremel.

It took me some time to figure out the cause but it appears that the chuck let the endmill slip and it plunged into the material too deep.

I’m not sure what to do but I am making sure the dremel chuck is really tight from now on.

Anybody know what size fuse to put inline with a dremel?



This morning I was making parts for a paper plane launcher and I blew a fuse on the spindle driver on my CNC. Well to be honest, I blew my spare fuse. 🙂 You can see the broken endmill right by the fuse. I added the multi-tip screwdriver for size reference.

It’s rather hard to read what’s on the fuse. It looks like: F6 L250V

It’s 20 x 5mm. [L=.7920″ (20.12mm), W=0.1965″ (4.99mm)].

Should I assume its a 6 Amp fuse that is rated for 250V?