Chamfering holes.

The metal has about as much to do with it as anything. Some metal cuts nice and some doesn't. Generally speaking the better the grade, the better the cut. Plate, of the type I assume you are using the most, often times just doesn't cut well. Plain old brown cutting/threading oil will help about as much as anything. I have this type to work pretty well with hand drills for light chamfering & deburring.

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Sorry about the BIG pic! Good luck, & hope this helps. :)
 
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I know this is probably nothing like what you're looking for, but we use these at work. We have 45 degree and 82 degree (for bolts). They work amazingly and will make a hell of a bevel with almost no spindle loads. The only thing that sucks is the Tungaloy inserts are about 80 bucks each...good thing is, they're tough and they usually last a long time. You can also flip them over.

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We use the ones Granny posted every day on fire truck stuff. They don't touch anything but aluminum (keeps em sharp) we also do it mostly by hand with a cordless on low speed. Cutting wax messes with the cut. I also took some counter bores for socket allen heads and machined the ends round for 10-24, 1/4, 5/16, 3/8 hardware for a pilot. I then back cut the flutes so they cut like a end mill. So what I got is a tool to cut the diamonds down clean and flat on ATP sheet stock so the fastener sits flush with the part surface when the hole is directly on top of those hundreds of diamonds. Done this with plain ole drill bits for a while but the flute is only so wide so a good chatter free pilot was hard to achieve.
 
The counterbore trick is probably gonna be what I'm after. I'm gonna do that to one and see how I like it. Seems like the flat cutting surface of the step will give me the result in after.
 
One more tip on this... get one for aluminum only. Don't use it on anything else other than maybe plastic. You will be surprised. Also, if you can still find any real lard it will do a lot in preventing aluminum from building up on the cutter. That is "old school" stuff. :)
 
In lieu of lard, soap works well. Ivory or whatever. I use it to keep aluminum from galling on burrs and sanding disks. Compared to my wax stick, the soap works almost as well, and is much cheaper.
 
I might as well chime in on this...
It looks like you aren't feeding fast enough to break a chip. However, it's evident you've experimented around and would have tried feeding harder, so I'd bet it's the material deflecting. Essentially if you push down 50 thousandths, the material deflects 30 or 40 thou, and you don't actually cut it enough to make a good chip. Then you end up dragging the material around, getting a crappy surface finish, and still having the bur. I've had the same thing happen on sheet metal, and usually I just put a junk 2x4 behind it and push till the bur goes away. If you're not doing it in a drill press it's going to be a lot harder, but if you can keep the motion captive and constrain behind the sheet, I'd bet a nickel that the bur will go away.
 
I use this on Wood, Plastic, Metal. In the drill press is much cleaner than by hand.

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Chris, are you just trying to clean up drilled holes? There are specific "crank style" deburring tools for the small holes...
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and use a whip deburring tool for larger holes...
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These both work very well in aluminum. This is what we used in aircraft. And both are faster than a machine bit!
 
I use those at work too. They work great!
 
mbalbritton said:
That looks like the ticket right there. You'll avoid chattering the edges like you'll likely get from a power driven bit.
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You'd be surprised how nice of a chatter pattern you can make with one of those. Good enough to make someone think it was machine deburred.
 
ol'Jeeps said:
Chris, are you just trying to clean up drilled holes? There are specific "crank style" deburring tools for the small holes...
View attachment 150792
and use a whip deburring tool for larger holes...
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These both work very well in aluminum. This is what we used in aircraft. And both are faster than a machine bit!
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I use one of those every day for de-burring sheet, tube, holes and everything else I cut. Probably one of the most underrated tool in a shop.

I'm starting to think I'm just too picky or have overly high expectations I guess. In playing around with it some more. A backing plate, very slow speed and lots of down force is working pretty well so thanks very much for that advice. I am ending up with a lot less actual material mushrooming up and out.

If money weren't an object these would be pretty slick. My dad was telling me about them today. Pretty awesome to be able to do both faces from one side of the material. These things are around 280+ each and I'd need at minimum 3 different sizes. Seem to only do down to .080 thickness and I need to be able to do .0625 not sure how they'd do in a hand drill though.
http://www.heuletool.com/pages/products/default/COFA/
 
Chris i will find a link if i can but me and another tool guy use to buy up old tooling from martin mareitta. They had the tool you needed, let me look at the shop i may still have one.
 
If we want to open Pandora's box of cutting tool options, that changes things. Theres a whole world out there for automatically deploying back spotface and back chamfer tools. If any of you guys are ever looking for something specific, let me know. I've been managing a $900k/year tooling budget for the past 3 years at work, and I see a lot of neat stuff that people want to sell me.
 
jeepinmatt said:
If we want to open Pandora's box of cutting tool options, that changes things. Theres a whole world out there for automatically deploying back spotface and back chamfer tools. If any of you guys are ever looking for something specific, let me know. I've been managing a $900k/year tooling budget for the past 3 years at work, and I see a lot of neat stuff that people want to sell me.
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holy tool budget batman! Where do you facilitate? I mean work?
 
WARRIORWELDING said:
holy tool budget batman! Where do you facilitate? I mean work?
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If I told you I'd have to kill you. You know how those German's are, especially the really big German companies that are in the power generation/energy business.
 
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