Drilling deep holes query.

[knuterikt]

Many thanks. Another one I came across was by Starrett.
http://www.starrett.co.uk/shop/hs_accessories/oopsarbor/
http://www.youtube.com/watch?v=iwvnsIYIOiw
It's just gets really expensive when you start adding all the bits together.

Why make it so costly and complicated?

To use the A19 'Oops' Arbor you must match the existing diameter exactly (or add tape on an undersized one)

Two normal hole saws is all you need.
One to make the centering plug out of a plank, this only going to cut wood. If you cant get an exact match go down and adjust using tape or go up and sand it down to correct size
One the size of the new hole, select a good quality one with HHS teeth's
But the wood plug onto the center bit on the large one and cut from both sides.

 

[knuterikt]

I think you would be suprised how easily the job will go with a good sharp holesaw correctly bushed to centralise it. Just run it in till it decks down then cut the core out with a good sharp chisel, in my experience the layers of mat are not always as well wetted out perfectly and you will be able to pop good sized chunks out at a time, a bit like you would going through plywood only a bit tougher. Messy job though - make sure you have a hoover running the whole time.

+1