Matthew wrote:

I need to drill two holes through brick walls in order
to install two 4" extractor fans. I have a bosch sds plus
drill but havent used core drills with it before.

The drill will have a clutch which is vital for jobs like this, what it
may lack (depending on model) is power. I have done 4" cores with my
780W drill and it just about manages - you have to take it easy or the
clutch will let go.

I guess there are two types diamond and tungsten teeth.
Not sure what make or what accessories are needed.
Its only the two holes so I dont want to spend too much.
Any advice?

Diamond core bit and a SDS arbour, and a pilot drill for the arbour.
Stick a 8mm hole through the wall first with an ordinary drill, then
follow with the core bit. The pilot drill will centre it in the pre
drilled hole (this save trying to drill using the pilot and no hammer
action!).

If you are doing both holes on the same day then hiring might be more
cost effective. Having said that if you buy it, you will probably find
other uses (and users) come out of the woodwork! So it may keep you in
beer tokens.

--
Cheers,

John.

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