ok to use water to cool down a forstner bit?

[jim dort]

Is it a good or bad idea to cool down (while it's revolving) a forstner bit? Will a wet bit which is then somewhat wet harm the stock?

[Biff Johnson]

Seems like it would make a heck of a mess and possible make drilling harder? How about using air?

[Peter Quinn]

Everything I know about wood screams BAD IDEA. Pouring water on wood while boring it? I see this adding friction, causing the wood to swell and grab the bit, interfering with chip ejection, rust, nothing good can come of this.

[glenn bradley]

Sharpen your bit so that it cuts cooler. If you are doing a long run of repeated holes, buy a couple extra of that size and cycle through them(?).

[Bill Huber]

I agree with Glenn and Peter, don't do it.
If the bit is getting so hot that you have to cool it, I would think the bit is really dull or you are trying to drill with it to fast.

[Sam Babbage]

I agree with Glenn and Peter, don't do it.
If the bit is getting so hot that you have to cool it, I would think the bit is really dull or you are trying to drill with it to fast.

More likely than too fast is too slow.

[jim dort]

what about just wetting the hot forstner bit (forget about wetting the wood)...does doing so while the bit is hot affect the bit?

[scott vroom]

What species of wood are you boring? Water anywhere near that operation sounds like a bad idea. As others have mentioned, better solutions are sharper bit/slower speed.

[Peter Quinn]

I believe heating steel then dipping it in water is the process for removing the temper. After that the bit will really dull quick. Better to get a good HSS bit, feed it moderately, spin it as close to the correct speed as possible. When drilling hard metal sometimes cooling fluid is required, but that's not water either. I've seen guys sharpening plane irons on a grinder use water to cool intermittently, but if you overheat then cool you remove temper and wreck the tip. Better to do it right than find some way to compensate for doing it wrong. A good sharp forschner will not struggle cutting wood.

[Gary Kman]

Go for it. If you had a good sharp bit that didn't overheat, you'd be done instead of posting here. I saw a brand new Forsner bit ruined (overheated until blue) at a workshop in a woodworking tool store! Whatever you are drilling has at least 8% water in it, what's a little more going to hurt. You use white or yellow glue don't you? Water. Wet the surface to raise the grain. Water. Aniline die? Water. Solvent free finishes. Water. The steel is as happy as a pig in mud in water. Tried to watch automatic machines making gears in the Harley Davidson engine plant in Milwaukee. Looked like fire hoses flooding the cutting area with fluid (mostly water).

If nobody ever tried anything new we'd still be chopping wood to shape with flint rocks.

[Chris Fournier]

What species of wood are you boring? Water anywhere near that operation sounds like a bad idea. As others have mentioned, better solutions are sharper bit/slower speed.

Slow speed is more likely the problem, not toofast. Truth is most drill presses will bog if the feed rate is too fast (given correct drill press RPM). Slow kills cutters of all kinds more than fast ever does.

[Jim Andrew]

Keeping your bit cool will not hurt it. Although, you do not want to get it really hot as that WILL remove the temper. I always keep some water handy when grinding my plane irons and chisels, and dip them often to keep them from getting hot. That's also the idea of the slow speed grinders with the water pan. Don't overheat your tools. But don't soak your wood.

[Ronald Blue]

Heat removes temper not water. Good high speed steel can take a lot of heat. But it sounds like your bit may be dull. What kind of wood are you drilling? Some woods are much tougher and tax drill bits more then others. I am not an expert on difficult to machine woods and will defer that to those who are. What size bit are we talking here? Speeds do matter and to fast even in wood can be an issue. More info could be helpful here.

[Mark Wooden]

Make sure your bit is sharp and has enough relief past the cutting area. I've had to hone several offshore bits because they were several thousandths bigger at the back of the bit.
Water is a bad idea all around- rust on the bit, iron contamination in and around the hole bored, poor glue area etc..

[Curt Harms]

A very quick google search found this chart:

www.infinitytools.com/PDF/Forstner_Bit_SpeedChart.pdf

The speeds seem higher than what I remember. I assume these speeds are for good quality HSS, infinity has a good reputation.