Festool Owners Group

GENERAL DISCUSSIONS => Home Improvement & Other Projects => Topic started by: Mike Goetzke on June 16, 2022, 08:11 PM

Title: End Grain Drilling
Post by: Mike Goetzke on June 16, 2022, 08:11 PM
My son wants to make candle holders out of hardwood logs by drilling about a 2-1/2” hole in the end with a Forstner bit.

The wood is ash and my 1hp drill press is stalling on the cut. I’m running the bit at 250 to 300RPM. I know end grain is hard to drill but any hints welcome.

( I did try a side grain cut and the bit cuts like butter)
Title: Re: End Grain Drilling
Post by: ChuckS on June 16, 2022, 08:48 PM
Drill the hole with a smaller bit(s) (1" e.g.), then change the bit to the final diameter, without changing any setting. Dust extraction helps too.
Title: Re: End Grain Drilling
Post by: Roachmill on June 17, 2022, 04:45 AM
To add to the above (given the size of hole) I'd maybe add a secured sacrificial piece on top for the final full-size hole to act as a guide for the bit and to eliminate any chatter as the bit hits the wood. He may get away without it... but end grain is hard going at the best of times.
Title: Re: End Grain Drilling
Post by: Mike Goetzke on June 17, 2022, 08:37 AM
Thanks for the help/comments.

After sleeping on it I was thinking my sample a piece of ash that I had on hand. It is a cutoff from a kiln dried baseball bat blank that has been sitting around for several years. So, this wood is probably MUCH harder than the real thing will be.
Title: Re: End Grain Drilling
Post by: Bob D. on June 17, 2022, 09:20 AM
Use a hole saw to get to the depth you need, then break out the interior waste with a chisel. Follow up with the Forstner bit to clean up the bottom.

Or build a jig to hold your plunge router with a guide bushing to rout out the needed size hole.
Title: Re: End Grain Drilling
Post by: mino on June 17, 2022, 10:58 AM
One more option is using a router bit in the drill press at high speed.

That way the momentum of the drill spindle should be able to handle any "bumps" of resistance better and the drill will be able to "flex its muscles" unlike at low speed where it is torque-limited.

I used that a couple times with a power drill in a press when the drill could not handle the forces needed to drive a Forstner at low speed. At 3000 rpm the router bit was still under its optimal speed, but enough to work out when the bit is sharp.

One more method I use /with forstners/ is to set the drill to top speed and quickly "plunge" into the material, knowing full well the bit will be stopped fast. But not before it manages a couple cuts just from its sheer momentum.
Given the bit is stopped after only a couple rotations in a cut, it does not overheat from the overly high speed. Rinse and repeat until I get the depth I need. Requires stable material holding though to have the "plunges" always in the same place and some patience to not overheat the bit by too-frequent plunges.
Title: Re: End Grain Drilling
Post by: Blues on August 19, 2022, 06:13 PM
Use a woodowl bit. It's all that you need.