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Boucher
01-09-2010, 11:46 PM
Thought you said run it dry and fast.
http://i109.photobucket.com/albums/n50/boucherbyron/IMG_0056.jpg
Bad case of BUE on Carbide Mill

Today I needed to make some fairly heavy material removal so it was a good chance to conduct some tests and try some new Glacern tools.
http://i109.photobucket.com/albums/n50/boucherbyron/IMG_0057.jpg
Cut 0.350 X 0.200 X 6 ipm

The 1" Glacern Indexable insert mill works great and
http://i109.photobucket.com/albums/n50/boucherbyron/IMG_0060.jpg

the 45 Face mill is even better.

http://i109.photobucket.com/albums/n50/boucherbyron/IMG_0061.jpg

Carld
01-09-2010, 11:58 PM
How fast was fast and what was the feed rate?

Machinist-Guide
01-10-2010, 12:21 AM
I don't think you should run alum. dry at any speed or feed.
use WD-40.Kerosene,Oil, spit on it, anything but dry.

Evan
01-10-2010, 12:47 AM
Dry works ok with the hard alloys like 7075 or 2024 but the rest need either kerosene, ethanol (for really high speeds) or WD-40 type lube. It must be thin in order to make it to the cutting edge and it doesn't take much at all. Just a thin mist is enough. I use a lighter and melt the tip of the WD-40 spritzer tube and then pull it out a bit to make the end a smaller diameter. Clip off the excess tube and it then cuts down the waste and mess.

beanbag
01-10-2010, 02:07 AM
I don't think you should run alum. dry at any speed or feed.
use WD-40.Kerosene,Oil, spit on it, anything but dry.

x2

I use mist coolant, either water soluble oil or Koolmist 77. Even a tiny bit helps prevent BUE.

MAYBE if you have a ZrN end mill, and you REALLY go at it with very very high SFM you can run dry.

Those who have run manly CNC machines can chime in.

Machinist-Guide
01-10-2010, 02:17 AM
I like mist systems. I mist every thing.:D
I mist the neighbors dog. Keeps him out of the shop:D

Bguns
01-10-2010, 04:46 AM
Dry hard and fast, WITH THE PROPER CUTTER....

A 4 flute is not optimum for ALU...

Need to take a cut, shove chips out with a high speed, high helix cutter...

The 4 flutes tend to plug up in Alu, and are pretty weak...

Anything works for a finish climb cut, but for moving a lot of cubic inches per min, dump the 4 flute and get a specialized Alu cutter...

I have to cut deep slots in 7075 Alu once in a while (3/8) end mill ~2 inch depth of cut) never plugged a proper Alu cutter...

Some of the Alu soft grades, and Copper are a PITA...

Black_Moons
01-10-2010, 04:59 AM
Yea the aluminum cutters are really something else, Usally highly polished flutes for extra low friction, high helix for extra high chip ejection rate, sharper/more rake for better finish at expensive of edge support (You'll ruin em fast in steel!) And usally you'll want a 2 or 3 flute endmill for those massive cuts as you need the chip space more then you need the extra flutes at the feed rates you can rough aluminum at. 4 flutes are for finishing aluminum or sidemilling with big open spaces for the chips to go.

Evan: ethonal?? isent that a little.. dangerious? :) Well, Moreso then the normal dangers... I would'nt wanna have to put my mill out. :P

Example of high helix: http://www.made-in-china.com/image/2f0j00VvCEiGhRHWoyM/Solid-Carbide-Square-Carbide-End-Mill-for-Aluminum-Material.jpg
Apparently they also help produce more vertical cutting force (trying to strech the endmill) then latterial (trying to bend the endmill) allowing even more feed without as much deflection.

Evan
01-10-2010, 05:23 AM
I use ethanol all the time on non-sparking materials. Never had to put anything out yet. I do have a Halon extinguisher a few feet away but it's still full. Ethanol is industry standard as a high speed aluminum coolant.

http://www.datrondynamics.com/

http://www.mmsonline.com/articles/alcohol-based-coolant-offers-environmentally-friendly-machining

http://www.moldmakingtechnology.com/articles/030402.html

http://www.60000rpm.com/PDF/2007_DPP(web)_PDFs/DPP_InLine.pdf

http://high-speed-machining.blogspot.com/2009/04/success-in-engraving-id-products.html

http://www.youtube.com/watch?v=uNUZTntg-uU

derekm
01-10-2010, 06:18 AM
Ethanol and methanol fires are easily put out with water.(water Soluble coolant being 95% water will work)
the difficult part is seeing the flame in bright light. - see Indy car racing

Your Old Dog
01-10-2010, 08:31 AM
Dry works ok with the hard alloys like 7075 or 2024 but the rest need either kerosene, ethanol (for really high speeds) or WD-40 type lube. It must be thin in order to make it to the cutting edge and it doesn't take much at all. Just a thin mist is enough. I use a lighter and melt the tip of the WD-40 spritzer tube and then pull it out a bit to make the end a smaller diameter. Clip off the excess tube and it then cuts down the waste and mess.

Wish the hell I'd of thunked of that! I'm knee deep in WD-40 when running aluminum. I'll try that and see if it ain't cheaper and less messy then the way I do it now.

MickeyD
01-10-2010, 09:38 AM
WD-40 works but is not the best thing to use for both health and cleanliness reasons. A water soluble coolant will do the same thing (often better) but not release as many fumes into the air (and your lungs), plus they are a lot easier to cleanup after. Part cleanup is actually important because if you every try to paint something that has been machined using WD-40, getting all of the silicone off of the workpiece (and surrounding ones) is a chore. A real soluble coolant will wash off much easier (by design) and make getting a good finish treatment easier. Another thing with the soluble coolants is that they are MUCH cheaper than using WD-40. Concentrate costs about $15 to $25 per gallon and will make 10 to 20 gallons of coolant vs. WD that is about $18 a gallon.

Tony Ennis
01-10-2010, 10:13 AM
WD-40, getting all of the silicone off of the workpiece (and surrounding ones) is a chore.

WD-40 has no silicone. It's a light oil in a convenient container. It's a poor lubricant (in the general sense, not the 'use it when milling aluminum' sense.) It was invented to be a cleaning solution. WD stands for "Water Displacement."

Machinist-Guide
01-10-2010, 10:36 AM
I don't use WD-40 like a coolant and get it all over every thing I put a small amount on my end mill and it keeps the alu. from sticking the the flutes.
For coolant I use coolant.

Your Old Dog
01-10-2010, 11:14 AM
. WD stands for "Water Displacement."

Correct-o-mondo! And remember that if you store pistol parts in a can filled with WD-40 and there is any water in that container such as you just finished washing the part off then the parts will be rusted when you take them out if you wait too long. (anybody want to buy a vowel or puncuation mark? !)

saltmine
01-10-2010, 12:41 PM
I once set my workbech at work on fire trying to make a fire extinguisher.
I guess I shouldn't have been so cheap, and actually went out and bought one.

lazlo
01-10-2010, 01:16 PM
That's the only good use for WD-40 - as an expedient aluminum coolant :)


I use ethanol all the time on non-sparking materials. Never had to put anything out yet.

A German fellow on PM mentioned that it's common over there to use windshield wiper concentrate (methanol) for aluminum. I tried it in my Accu-Lube mister, and it works great (smells good too). The lower the temperature rating, the higher the methanol concentration.

aboard_epsilon
01-10-2010, 01:46 PM
Thought you said run it dry and fast.
http://i109.photobucket.com/albums/n50/boucherbyron/IMG_0056.jpg
Bad case of BUE on Carbide Mill



dont look like carbide to me ..looks like hss

all the best.markj

spope14
01-10-2010, 02:18 PM
I use a product called edge lube for milling, turning and tapping aluminum - using HSS or Carbide. also in tool grinding. It is a wax type of product that I smear on the edge to be milled or the surface to be turned.

http://www1.mscdirect.com/CGI/GSDRVSM?PACACHE=000000122277453

This is probably the equivelant of Acculube paste, which I used to use as well.

The stuff melts just enough right before the cutting edge. Works absolutely fantastic, and a 16 ounce tube costs very little all said and done, $17.00 but my tube has lasted about five years. Clean-up is very easy, no spray mess or mixing of WD with the machine way oils. Chips are easily vaccuumed up with a shop vac because the wax returns to form on the chips, or smokes away (very low burn off point, but not flammable) and is not sprayed all over the place - unles you paste it on heavy - which is not what you should do. On small machines like benchtop CNC's there is no problem with oils where they may not be desirable- and on the little benchtops I have that have fully enclosed environments (and door switches), this is great stuff. Been using it for about 15 years now. Very little BUE if any, and for chip "recutting" that sometimes occurs with flycutting, this stuff prevents it quite well.

It is also pretty safe for people and animals, and in my garage shop, it is invaluable because I don't get sprays all over everything.

If you don't like this, a bit of tap magic also works very well. Though a can of this costs more than WD40, the actual use is less. Use a small can and acid brush to apply.