baloney to high speed drilling

[Rifleman1776]

In discussions past, some members have advocated drilling blanks using high speeds on their drill press. I generally use relatively slow speeds (300 to 500 rpm range). Recently, doing a different operation, I set my press to it's highest rpm, 3050. Today, I went to drill a goncalo alves Tigerwood blank but had forgotten the press was at 3050. As soon as it came on, I noticed the high speed. Thinking that those who advocte such speeds cannot be all wrong, I tried it. Uh-Uh! [V] They are wrong. Less than a 1/4" into the blank (7mm brad point bit) it was smoking like a barbeque. I stopped and touched the bit, too hot to touch. I lowered the speed to my usual and finished. No doubt that blank would have exploded had I tried going the full depth at that speed. Slow does it. And it saves blanks and bit. And nerves.

 

[dubdrvrkev]

Slow and steady wins the race. I drill on my lathe at the lowest speed, occasionally I'll drill at the next speed up.

 

[Old Griz]

Drilling blanks at high speed is asking for trouble... I never drill at high speed.... and often remove the bit to let it cool...

 

[Geo in Winnipeg]

I drill at 500RPM max. and clear chips often. If it's dymondwood I'll also squirt water on the bit to cool it. I drilled dymondwood once ('O' drill) without water and only cleared the chips once and the blank cracked from the heat. When the blank cracked the bit was too hot to touch.

 

[GregD]

For all you speed deamons out there. Here is a link to a drill press speed chart.
http://justwoodworking.com/charts/drill_press.php

 

[btboone]

I ususally stick to 1500 rpms on most of my stuff. Looks like the chart agrees with that for my normal twist drills. The trick is clearing the chips. I clear them every quarter inch or so. There's no down side to slower though, as long as the drill is not asked to take too much of a bite per revolution. The drill walks in that condition.

 

[DCBluesman]

Heck, this post is aimed directly at lunatics like me. Guess I need to look into going slower.

 

[Ron in Drums PA]

Speed Kills

 

[alamocdc]

Until about two weeks ago I was right there with you, Lou! My DP was at teh factory default of 1390. I dropped it to it's slowest speed (590) and I've been much happier. I just wish I could slow it down more. For slower speeds I drill with my lathe. And it gives me the added bonus of letting me drill longer blanks w/o moving my DP table.

 

[tinker]

My DP has been set at the lowest speed since I bought it. Metals require different speeds, but wood is easy does it.

 

[fritzmccorkle]

when i first started making pens i bought a new drill press and was having troubles. i slowed down to 480 and have used that speed on all size bits, wood, and plastic without problems. i've been told that i am set too slow, but i don't have any trouble so i see no need to speed up.

 

[scubaman]

Originally posted by DCBluesman
<br />Heck, this post is aimed directly at lunatics like me. Guess I need to look into going slower.

Why? Because other lunatics (from a different moon) say so? [] If it works for you, don't change! There are many factors involved. A bradpoint bit is NOT ideal, IMO. Yes, I found those smoke easily (and for me didn't drill all that straight). Also, don't forget we typically drill end grain, drill charts for wood usually are for face grain. So go slower yet than the charts??? Yes, if that's what it takes to get your blanks drilled!

Through trial and error (I also had a slow-speed phase) I found what works for me. I don't like changing speed a lot, so I drill almost everything at around 2000 RPM. When I do acrylics, I slow down to 1200 RPM. I don't necessarily change speed immediately when I get back to wood. I won't tell others where they should drill - I just know what works for me. Key is feed rate and chip removal - if the flutes clog like with desert ironwood you just need to retract often.

 

[DCBluesman]

Ok, I've read the replies and looked at the link (and others that have been supplied from time to time). My question is "Where's the science?" I've been drilling wood blanks for months full out. I don't blow up blanks. I don't get cracks. There's got to be a reason to change...something with the power of fact behind it. Can someone point me to a definitive discussion where the information presented is more than apocryphal?

 

[wdcav1952]

We'd love to Lou, but most of us don't have the faintest idea what the word apocryphal means! [8D]

As for me, my drill press is a Craftsman that is at least 40 years old with a Grizzly motor and pulley wheel jury-rigged to it so I don't have the slightest idea what speed it turns at. Like Rich said, feed rate and clear the chips often.

 

[PenWorks]

I have my Jet tuned to about 1650, I think that is what Brea recomends for their parobolic bits, which I tend to use alot. Works for me.
William, do you think Lou spelled that right ?? []

 

[alamocdc]

You want science, I'll give you science. [)] Okay, enough clowning around. What I do know is simple physics. More speed equals more friction. More friction equals more heat. This is unequivocal. It has been posted time after time that heat is an enemy to many of the exotics that most pen turners gravitate to. That should be simple enough. If you are having success drilling at higer speeds, more power to you. When I slowed down, I noticed an improvement. And I agree with Rich on one point. Brad Points are great bits, but I've had better luck at times with spilt points. BPs aren't supposed to wander as bad because of the way they cut, but grain can do funny things to a bit's track. The amount of material missing from the flutes can also make a difference (the bit will be more flexible). Speed it up and the deflection is magnified.

 

[Fangar]

I use a small vacuum to clear the chips as I drill. Works well.

Don't drill on "speed" for sure!

[]

Fangar

 

[wdcav1952]

Originally posted by penworks
<br />I have my Jet tuned to about 1650, I think that is what Brea recomends for their parobolic bits, which I tend to use alot. Works for me.
William, do you think Lou spelled that right ?? []

Yes Anthony I think Lou spelled "that" right. The big word I'm not sure about, though.

[][}][]

 

[Rifleman1776]

Originally posted by DCBluesman
<br />Heck, this post is aimed directly at lunatics like me. Guess I need to look into going slower.

Have you tried Lithium? [][]

 

[Mudder]

Originally posted by wdcav1952
<br />We'd love to Lou, but most of us don't have the faintest idea what the word apocryphal means! [8D]

a·poc·ry·phal adj.

1. Of questionable authorship or authenticity.<br />
2. Erroneous; fictitious: “Wildly apocryphal rumors about starvation in Petrograd... raced through Russia's trenches†(W. Bruce Lincoln).<br />
3. Apocryphal Bible. Of or having to do with the Apocrypha.



I agree with you Lou. I drill pretty fast and have not had any problems.

 

[wdcav1952]

Uh, Mudder, now look up the word joke. []

 

[coach]

I'm heading out for a coaching convention, but ran outside and slowed mine down to 500 I think. It was going fast. Drilled 5 bottle stopper blanks real quick. They drilled very nice. It did make much nicer shavings. I think I'll just slow down then.

 

[scubaman]

Originally posted by alamocdc
<br />What I do know is simple physics.

Me too [8D]

More speed equals more friction. More friction equals more heat.

And higher feedrate equals less heat [] Slow feedrate equals more friction i.e. more heat and less efficient chip transport up the flutes. BTW, a vacuum (someone mentioned that) does not lift up chips, it prevents them from piling up around the exit hole and dropping back down, so it does help somewhat (as does drilling horizontally)

Somewhere in that parameter space everyone needs to find what works for them

 

[DCBluesman]

Originally posted by Rifleman
Have you tried Lithium? [][]

It doesn't mix well with my Prozac and Haldol. [8D]

 

[Travlr7]

It's interesting that I saw this thread today. I was remembering comments about "Blowing out the ends while drilling and cracking blanks". Yesterday, I drilled 120 blanks, non-stop. They included Cherry, Mahogany, Maple, IPE, Walnut, and some other hard, but unidentified woods. Not one blowout or overheated bit. I drill at the lowest speed (540) available to me. Today, I inserted a pen mill and trimmed all those blanks. No problems, either. Not a scientific study, but I'm a believer of Slower is Better.

Bruce

 

[ctEaglesc]

NOw you guys have got me thinking to go out and look at the speed I drill/mill at.
Don't change speedds,use brad point, parolbolic bits.wood. anthler, have no idea whether it's end grain cross grain whatever,
Nere would dream of pputting a drop of water on a blank,vacuum?
I need a vacuum to find the shop vac.
I'll be right back.
(going to check pulley speed)
Now I wish I hadn't looked at this thread.
the way I have my belts set it doesn't show it on the chart.
It's almost set for 400 but I have the belt on the motor one step higher intead of going straight across.
IT AINT BROKE AND I AINT GOING TO FIX IT!
One thing I recall from reading an article on shrapening.
The slower the speed, the longer it will take to do the job. the longer it takes the more chance of heat build up.
Water?
You have got to be kidding!

 

[Fred in NC]

Whatever type of drill bit you use, if it is dull, it will not cut.

If it is not cutting, but is turning around inside the blank, there will be a lot of friction, and friction means heat.

Drills are just like any other cutting tool. Sharp works better.

 

[Ron in Drums PA]

Fred, Russ is right.

There is a beauty supply shop by me that sells emtpy plastic bottles. They cater mostly to saloons but they will sell to any confused looking guy who happens to walk in.


Edit

I wonder what I did wrong, this was to be in a different thread. [?]

 

[wdcav1952]

Originally posted by Ron in Drums PA
<br />Fred, Russ is right.

There is a beauty supply shop by me that sells emtpy plastic bottles. They cater mostly to saloons but they will sell to any confused looking guy who happens to walk in.

Ron,

Is Miz Kitty in that saloon?
[][}][][}][][}]

 

[Mudder]

Originally posted by wdcav1952
<br />Uh, Mudder, now look up the word joke. []

joke
n.

1. See apocryphal. []

 

[cigarman]

If you are going to drill at a fast speed, (and I do), don't forget when you clear the chips to clean out the flutes on the drill bit. I keep a metal brisel brush on my drill press for that job. I also have a spray bottle of water to cool the bit off.

 

[RussFairfield]

It seems to me that how much wood is removed per revolution of the drill is what is important. A sharp drill should be removing at least 0.005" per revolution, a chip the thickness of a piece of paper. That means that, at 3000 RPM, we should be going through the average pen blank in about 10-seconds. Anything longer than that, and there's a whole lot of spinning going on, and not much work being done. And that is the recipe for heat.

 

[ctEaglesc]

YOu guys are way over engineering this.
it aint Rocket science, it's a frigging pen[^]

 

[Old Griz]

<b>AMEN Eagle.....</b>

 

[wdcav1952]

Actually Eagle, it's a frigging drill at this point. We'll get to the frigging pen in a frigging minute. Wait a minute, did I see Griz agreeing with Eagle?!? "It's a big one, Elizabeth, I'm comin' to join you!" []

 

[Fred in NC]

Russ, man you must be very wealthy !!! That must be thick, very high quality writing paper. []

 

[woodwish]

I'm with you on this one Eagle and Griz! []

 

[clem]

try drilling plastic at high speed and see what you get

 

[ed4copies]

Clem,
An awful smell!!

 

[ctEaglesc]

Originally posted by clem
<br />try drilling plastic at high speed and see what you get

I have done a couple of acrylics, plastics what ever you want to call them.
I do realize that manmade materials have different properties and "plasstics" require different techniques.
I ronically with the laminiated blanks I am making I can actually drill faster witht he CA in them.(CA being plastic)
Bottom line is if you are doing an operation that requires cutting the tool needs to be sharp.