Drilling really large holes - how?

[opticsguy]

I am interested in boring very large holes in wood. 5-8" diameter in wood up to 12" thick.  How?????
Edit: I am needing to make smooth walled holes, just like you get when drilling with a 1" forstner bit, except a lot wider and deeper.
Thank you.

[meackerman]

Router and trammel will get the diameter. Not sure how to get the depth

[Arlin Eastman]

Can you take a Sabre saw or Reciprocating saw to both sides?

I had to do this before but nothing that thick just 8" and a Jig saw just would not go deep enough

It would be good to first to drill as deep and wide as you can first then saw.

Last you can find 10" to 12" drill bits to go thru all the way.

[MikeBob]

The only way I  can think of is on a lathe and use a chisel. Or cut out on a band saw. Good luck!!!

[MarkSingleton]

Boring head in a floor drill press.

[Routerman]

Seems like an impossibility.
But where in the hell do you get 12" stock?
Maybe 6 2" pieces?
That could be done. And then pin register and glue or screw
the stack.

[Bibliophile 13]

That's lathe work. Ask down in Woodturning.

[gMike]

I just did a 5.5" hole with smooth sides in 4" thick hard maple.  I drilled it out with a series of holes with a forstner bit and cleaned up the sides with a pattern bit and template of the 5.5" circle.  There were about a thousand ways for this to go wrong but I got lucky and it came out OK with a little sanding.

[Bob10]

I don't see much problem 6" and smaller but 8" you could manage with this from both sides clear and start again. I would drill all the way through with a bit the same size as the arbor that fits the hole saw. Use threaded rod that can reach all the way through tighten the bit with nuts to keep the saw from moving chuck up the end drill. I had a crazy thought of using bandsaw blade to make the hole saw to do the same as above might be slow going I don't know if the measurements need to be exact or merely allow something to pass through
http://www.customholesaw.com/index.php?m...cts_id=631

[opticsguy]

OP here. 
Where do I get 12" stock?  First I cut down a tree. Then haul it over to my band saw mill.................. cut anything I want. 
The very very best power tool I ever bought!!  Opens up all kinds of crazy ideas for woodworking, thus the question about boring large holes in thick stock with smooth sides.
I now remember seeing large treated posts at docks on the waterfront with large holes but I would guess they are "only" 4" diameter but also thinking I have seen larger, so wonder what machinery is involved in the process.