What wood drill bit type - 14mm, 24mm and dog holes?

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Hypnotic Chimera

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Hi folks

I've only ever used the flat blade type for drilling larger holes into wood.

Can someone educate me on whether forstner or augur or brad drill bits would be "better" than spade bits to drill the through-holes into my worktop frame to install a vice into/under my worktop.
I'll be using a hand drill in situ...
The vice screw is 23.4mm dia (24mm drill?); and support rods are 13.5mm dia (14mm drill?).

I guess the same question for dog holes? Which style bit to use? 19mm or 20mm??
 
I’d use a star m auger bit - they give very nice clean holes.
You could use a Brad point (star m 601 type bits are nice) but an auger will be easier to drive in that size.

For the vice I’d give clearance on the screw hole (25mm) but try to avoid slop on the support rods (14mm)

For dog holes it depends what dog you are using - worth testing on a bit of scrap before committing on the bench
 
Look at pictures of the UJK parf guide setup. That uses a specific forstner type bit to drill dog holes and it works well. I have armeg wood beaver and similar and don't think they cut quite such a clean edged hole.

Self driving auger bits with a screw point do tend to cut a really nice clean hole because of the curved shape to the spur on the outside. They are great for making holes to clear the screw or rods of a vice.
 
I've always found the auger type bits to be the easiest if you happen to have the right size handy.
But for odd sizes, and flat bottomed holes, I've filed a flat bit to suit before now. That's how I put the dog holes in the 30mm oak top I put on the old workmate. Heavy but handy. Just filed a flat but up with small scribers to suit. Spot on for fit.

And yes the top is a bit heavy, but I liked the strength over the portability!
 
A vote for the star m 601 which are fantastic, but for bigger sizes the F type augers are really amazing. I like the way they don`t pull into the cut like normal auger bits do and they don`t break the back of the hole out much either.
 
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