SDS Question

[ray.birch]

Good evening everyone. I’m currently having to use my SDS Drill (Dewalt DCH273) to slightly widen the hole of a very old 4” extractor fan duct.
I’m currently using an angled chisel to just gradually remove bits along the side of the hole, and generally have been seeing progress…

HOWEVER, I’m noticing that unless there is serious pressure on the drill, then you don’t really get the “percussive” effect. i.e. if I manually push the chisel really far down into the chuck, then all is fine and it chews through the brick like butter, but if I don’t have enough pressure or indeed pull the drill bit a little bit out, then the drill sounds like it’s doing something, but I don’t get any of the energy on the bit.

From what I can see, the bit is fully engaged (i.e. I can’t pull the bit fully out - just a little bit further out than the hammer action of the drill would seem to reach!).

Is this normal? In normal drilling, you probably wouldn’t notice (as there is always pressure on the bit), but it’s only here, where I’m chiselling at an angle, where I’ve seen this.

Many many thanks in advance!

 

[Wayners]

Yes.
I had a SDS Hitachi drill that after storage it took a while to get the hammer going. Also took some weight behind it to get the hammer going. Especially with the chisel.
That one got stolen.
My cheap replacement SDS is like yours. Hammer action don't do anything without the weight behind it.
I think it needs something solid to get the hammer bounce going. My cheap one sounds like yours with the action.

 

[Harry Bloomfield]

Is this normal? In normal drilling, you probably wouldn’t notice (as there is always pressure on the bit), but it’s only here, where I’m chiselling at an angle, where I’ve seen this.

I have three sds drills here, and they all behave exactly like that - it is quite normal.