SDS newbie question: why does chisel rotate?

You need a slightly better SDS drill that has not only a rotary off but a rotary *lock"

Owain

Not all SDS drills lock the rotation when in rotary stop mode. However, I would say that one which generates rotary motion in the way you describe is faulty or not fit for purpose. If you said what make/model, someone may be able to confirm or refute this as normal behaviour.

Make?

My 30 quid screwfix special does exactly the same thing. Haven't used it for a while, but I seem to recall just holding the chisel would fix it. Don't tell H&S.

IMHO; using a SDS chisel (bit) and the SDS drill (rotary stop) is just like using a manual chisel and lump hammer. I hold and guide the chisel with my left hand while the SDS drill body is supplying the 'thumping' (technical term) that the hammer would produce: It's less tiring and more accurate as the bit thumper produces more effort and faster than one can hit a chisel with a hammer. It's very heartening to discover just how much heavy thumping and delicate tapping can be produce from one tool.

It is a known problem with (typically) the budget SDS drills, and indeed some of the older quality brands. Better ones allow the rotation to be locked off, and the best will allow you to set the angle of the chisel before locking it.

Sounds like the design of some lower end models. My DeWalt allows the chisel to be locked in a variety of positions.

Even the cheapest lock if you use a bit of coathanger and a wire tie.

Thanks for your advice everyone.

My SDS is fairly cheapo - Black and Decker, cost =A365. Looks like it just does not have rotary lock. Still, it will do - I almost bought one that did not even have rotary stop, not realising that some of them do not have it.

Regards, DP (the OP)

Interesting. How do you do this?

Thanks, David P (the OP)

You bend it around the chisel/chuck and a suitable spot on the drill. It has to have enough spring in it to cope with the small amount of movement you get with the hammer.

My £200 Dewalt doesnt have a lock either, which rather surprised me, but being as I bought it as a drill, it didnt really concern me. Alan.

Which model? I thought they all had locks if they have rotation stop.

On Wed, 15 Aug 2007 19:39:48 +0100, "Dave Plowman (News)" mused:

DeWalt or in general? In general, not all do.

Turns out it's a cordless. Not surprised they don't encourage you too use it as a chisel.

Ah - a cordless. Didn't consider those.

On Wed, 15 Aug 2007 22:59:08 +0100, "Dave Plowman (News)" mused:

My Makita 24V with rotary stop locks.