How to stop the squeal????

[Brandon25]

Drilling a 27/64 hole for the first time last night. Before this only 7mm up to now. The bit is from the big HF set, and never been used. I drill on my lathe. The squeal that this thing emitted was enough to wake my wife two floors up, on the opposite side of the house. How do you avoid this squeal? I was drilling around 800rpm, but it even squeaked loudly when I turned it by hand with the lathe off. Do I need to add a lube, or maybe predrill a smaller hole? There were no clogged wood chips in the blank or on the bit flutes.

 

[thewishman]

First time I drilled on the lathe - 1800 rpm - neighbors came over to see what was wrong. I drill at 500 and some materials (usually wood) just make a LOT of noise.

 

[DurocShark]

Yep.

HOWEVER-- I found that a sharp, quality bit will squeal MUCH less. For my 27/64 bit I bought the $10 german one from Woodcraft. It's longer than a typical bit and cuts very nice. In coco it didn't squeal or smoke at all.

 

[scotirish]

If the flute of the drill bit becomes "loaded" with material and does not pass it up and out of the hole, that material will rub against the blank and cause not only friction and heat but will squeal.

 

[Gulfcoast]

Brandon

What you can try is to drill first with the 7mm drill, then follow with the 27/64 drill. The problem is that you are removing quite a bit of material all at once, causing a lot of heat and friction on the drill, thus the squeal. Incremental drilling (with sharp drills) will usually reduce the squeal.

Joe

 

[Rifleman1776]

Sharpen it and pay heed to what scotirish said. Withdraw and clear flutes frequently.

 

[Daniel]

My first guess would be you need to back the bit out and clear the chips more often. you can drill deeper with the first pass than you can with the rest. Other than that I have noticed another cause of squealing. I am not certain on this but this is the impression I get. once the flutes have been overloaded, causing the friction and squealing, the blanks and bit have also already gotten warm if not outright hot. Heat causes expansion and I suspect that the fit of the bit becomes pretty tight even with out any further drilling. try letting everything cool down for a bit and see if it helps.
I would not use any lube of any type on wood. water for acrylics and I have heard of people even using oil on acrylics but I would worry about getting it cleaned up well enough to glue the tube later.
Just in case you really want to presue the lube for wood idea plain old wax (even a candle) is used a lot in other situations. of course remember that ca glue will not stick to wax.

 

[marcruby]

[water for acrylics]

Speaking from experience this isn't a good idea. Water gets flung around, and while you can clean up what lands on surfaces you can't clean up what goes into the inside of the chuck. One of mine froze up completely and it took a condiserable amount of work to rescue it. I wound up buying a keyless Jacobs chuck, the upside of which is that I love it, and the downside is that it cost me 50 bucks.

I have used wd40 on wood and resin, as long as I remember to clean up with acetone or alcohol I haven't had a problem. This should work with most oils and some waxes. Soap might work as well, now that I think of it.

Marc

 

[1080Wayne]

Brandon Setting up your shop vac to pull the chips out of the hole as you drill reduces heat build up and squealing . May not work quite as well in oily woods . Daniel`s advice re frequent backing out of the drill bit is best general rule . Wayne

 

[Rifleman1776]

I didn't see you mention the problem with non-wood materials. But FWIW, I keep a couple large syringes on hand. Without needles on, I'll fill with water and drip/drop onto synthetic materials while I am drilling. Very little is required and it works well.

 

[Brandon25]

Rifleman, I've only made one non-wood pen. I'm very new, maybe 25 pens total.

All others, as I said, the flutes were clear, and the squeaking happened even when I had the lathe off, turning the wheel by hand. I suspect Daniel might be on to something with letting it cool down and shrink back up.

I also get the sense it's one of those things ya kinda just deal with. I might try pre-drilling smaller and see if that helps. Thanks, all.

 

[workinforwood]

Why not just trade drill presses with me? Mine never squeals. If the wood gets too overloaded, the press simply stalls out and if you don't turn it off then it begins to smoke a few seconds before the circuit breaker kicks off.

 

[Brandon25]

Sounds good to me! So, let's see, you send me your worthless one, and I send you my imaginary one. I bet my shipping is less.

I drill on the lathe.

 

[Rifleman1776]

Rifleman, I've only made one non-wood pen. I'm very new, maybe 25 pens total.

All others, as I said, the flutes were clear, and the squeaking happened even when I had the lathe off, turning the wheel by hand. I suspect Daniel might be on to something with letting it cool down and shrink back up.

I also get the sense it's one of those things ya kinda just deal with. I might try pre-drilling smaller and see if that helps. Thanks, all.

This is the kind of problem a forum is really all about when it comes to the helping part. Without being there, we have to take some guesses.
OK, flutes were clear. I'll make another (educated) guess. The bit may have been sharpened incorrectly. If the bit is a brad point (was it?) and the cutting wing was sharpened from the outside, you will get the problem you described.
Brad points must never, ever, never-ever be sharpened from the outside. If you do, the cutting edge is smaller than the rest of the bit that follows and you will get binding and squealing.
I suppose an improperly sharpened twist bit could have the same effect although only the end is (usually) ground when sharpening those.
To solve your mystery, you may have to purchase another bit of the same size but a different manufacture and experiment.

 

[Brandon25]

Frank, to answer your question, the set of bits I have are the harbor freight 135° split point design. I'll take a look at it tonight to see if there is anything unusual about the look of the sharpened point. The other (smaller) bits I've used from the set have showed no issues thus far.

 

[Daniel]

I think Frank still might be onto something. The point could be ground off center. this could cause it to actually be trying to wobble in the hole causing way to much friction. You can simply resharpen them so the point is centered. Finally just keep in mind that when drilling a blank you have a lot of bit down in the wood simply rubbing even if it is not cutting anything. I notice a lot of my wood blanks try to squeal just as I about finished. Right at the moment they start to drill through the bottom of the blanks they give a quick squawk. I think that is also the bit getting pushed to the side a little as well.

 

[Brandon25]

Is there a way to sharpen the bit myself? I dont have a drill doctor, or even a file, or diamond card or anything. I have only an 8" dry grinder.

 

[Brandon25]

Frank, I checked the bit and it looks like the others. Also, the bloodwood was the only blank I've drilled that big a hole in. Last night I drilled a piece of wenge with the same bit and there was much less squealing. It did squeal some, but it was tolerable, as in, it wasn't loud enough to cause physical pain to me.

 

[MobilMan]

Could be the piece of Bloodwood wasn't completely dry inside & binding as you drill. Finish drilling it out & see how the tube fits. Does it slide thru? Then leave it sit for a few hours & try the tube again. It may be tighter. I've had some blanks drilled 7mm that swelled so much inside I couldn't push the tube in with out force---had to be redrilled. And this was on 'supposedly' dry blanks.

 

[Brandon25]

I didn't notice the hole changing sizes on me via swelling or shrinking once the hole was drilled, but I glued the tube pretty much immediately. Incidentally, everything turned out well for the blank. Here's the pen it made:
http://www.penturners.org/forum/showthread.php?t=37411

 

[MobilMan]

Looks like all the noise was well worth it. Nice looking pen. Good going.

 

[stolicky]

I honestly think it comes down to heat, the heat expanding the metal in the bit (it doesn't take much), and the resulting friction on the sides of the hole. The deeper the hole, the more friction on the side of the bit.

I have gotten to the point where I: 1) take several short passes and relieve the material often, 2) have my shop vac nozzle sitting right next to the hole, and 3) wear ear protection.

Remember that less heat build up on the bit extends its life. I find that I get some degree of squealing regardless of point type, or quality.

Hey, the pen came out good!

 

[Brandon25]

Thanks for the pen complements. And my suspicion is that heat IS the primary culpret. The wenge wood that didn't squeal as much drilled more easily, and the pored are larger, so it didn't create that much heat, and squealed much less.