"John Stumbles" ] wrote in message ...

The rotary (tct-studded drill) bit makes a hell of a lot of dust, and isn't
that quick. I haven't used it since the time I did a dozen or so boxes in
one room followed by a couple of hours cleaning (the room and myself) up
afterwards! (If you want to buy a slightly used one I'm up for offers :-).

I didn't buy the box-shaped bit.

They (SF) were also doing a sort of bed-of-nails-on-a-stick tool a while
back, but it doesn't seem to be in the catalogue now. Don't know if they
were any good.

I can't see any of them being worth the money - I can make a neat
(neat in the sense that it takes a rubber mallet to seat the box)
cavity in less than five minutes just using an SDS drill, followed by
a 20mm SDS chisel.



On a similar note, what about the channelling chisels (d16724 etc.)?

They work, but the first one I had broke off at the SDS end of the shank
after a while, followed by the drill I was using breaking at the chuck!

Because of the way the tool shank curves ...

---------
\
\ chisel
------|____

... it generates a lot of sideways impact force which I suspect was what did
for chisel and hammer. If they'd designed it with a straight shank ...

------------------\____

... and with the chisel end slightly offset (imagine a slight rake upwards -
impossible to show with ascii art!) I think it'd be more robust.

I use a 22mm SDS gouge, from Axminster. It is as you describe, does
the channelling beautifully, and cost £4.95.



For box sinking I tend to put in a few holes for the the corners and to
break up the body of the cut (and to set the depth) and use a straight
chisel to cut out the rest.

This is the method that I use (see above),