[Shop-talk] 1" hole through cinder block ?

[Drew Rogge]

Can you get to both sides of the block? If so how about something like
one of those hole saws with carbide grit on the edge instead of normal
teeth? Of a diamond hole saw that you can get at the rental places?

Randall wrote:
> I'm working on plumbing (and wiring) a new air compressor for my shop.
> Turns out the 3/4" air line needs to run through some decorative cinder
> block.
> 
> Any suggestions for how to cut an approximately 1.25" diameter hole through
> the block, with the least risk of breaking the whole thing in half ?  
> 
> I see HF has spade-type masonry bits to 1", with turned down shanks; but I'm
> not sure how to enlarge the resulting hole.  
> 
> Any suggestions ?  I've got an ordinary 1/2" drill motor; really don't want
> to have to buy a hammer-drill for just this one project.  Also an air
> chisel, but I'm worried breaking the block with it.
> 
> Randall