how much drill press for 3&1/2" forstner bit?

Advice – - I have a 3” forstner bit that I have used several times. I find it is much easier (and you will need less drill press beef) if you drill the hold in steps.

Make certain that your stock is securing clamped in place. I use the 3” bit first just to establish the perimeter of the hole, barely scratching the surface. Then I use a 1.5” bit, followed by a 2.25” bit, followed by a 3” bit.

It takes some time, but drilling a 3” (or 3.5”) hole into a hard wood is pretty difficult otherwise.

-- Rich, Cedar Rapids, IA - I'm a woodworker. I don't create beauty, I reveal it.

Most drill presses have fractional HP. I know the 1/3hp motor on my drill press is enough to drill a 3” hole, I doubt it would get bogged down on a 3.5”. Really it just doesn’t take much hp, but you do have to go slowly.

I drill 3 1/2” holes with a forstner on my 38 year old 3/4 hp drill press in ebony and bloodwood, and have no trouble. The most important consideration is speed. 120 rpm or slower. Pick the dp that allows you to get into that range. When you start the hole, be gentle, hesitate before you fully engage the bit, and back it out often to clear chips. Make sure the workpiece is firmly clamped to the table.

Steve

-- Steve in KY. 44 years so far with my lovely bride. Think I'll keep her.

I have a 1 hp and a 1/2 hp drill press. The 1/2 hp will barely drill a 2” hole and the 1 hp has never bogged down on any drill. I’ve used it for 4” hole saws also. Fussy says his 3/4 hp drill works fine (agree also with his speed recommendation, although not many drill presses will turn that slow),so I guess it’s your call. Can’t have too much hp on a drill press.

-- Tim-- http://www.tmuli.com

Kirk,
I’d use a router for the interior cut.
A 1/2” MDF pattern and a bowl bit. Or, if you prefer a sharp transiition at the bottom, a pattern bit.
JMO, but I’d make the exterior square. Maybe a small chamfer the top edges.

-- Gene 'The true soldier fights not because he hates what is in front of him, but because he loves what is behind him.' G. K. Chesterton

Get your board sized and use the forstner bit first. You will have a much easier time clamping a large board than individual round blanks. Set a progression and move the board in successive increments. When you have all the counterbores in the board, do it again and cut them out with the hole saw.
OR….....
Cut out the coasters with your hole saw and turn the counterbore’s on the lathe. Safer and controllable.

My 2 cents.

-- Government does not solve problems; it subsidizes them.

All great info. Thnx u all. Keep it comin plz

-- When there's frost on the pumpkin... it's time for chubby dunkin'!

Genes router suggestion sounds like a winner. Besides the bowl bit is cheaper than a 3-1/2”forstner. If that isn’t in the picture like others pointed out…advance slowly.

-- Don't rollerskate in a buffalo herd

Honestly, you don’t need much power from a Drill Press. Just take the holes slowly and be sure not to over heat your bit and your fine.

This whole project simply begs to be done on a lathe with a good chuck. Save the money you’d spend on an enormous forstner bit which will have little value otherwise in your shop, and get your drill press with that money instead.

-- Einstein: "The intuitive mind is a sacred gift, and the rational mind is a faithful servant. We have created a society that honors the servant and has forgotten the gift." I'm Poopiekat!!

Poopiekat is right.
Not being a turner, I immediately thought of the router.
Actually, for multiples, a router and pattern(s) would likely be faster.

-- Gene 'The true soldier fights not because he hates what is in front of him, but because he loves what is behind him.' G. K. Chesterton