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spongerich
03-16-2015, 12:53 PM
I'm going to be making some T nuts on my Atlas horizontal milling machine.

I have a nice sharp 3" cutter that's just about the same width as the material that I need to remove.

Is it better to make a full width cut that's a few thousands deep, or make a full depth cut that takes a few thousandths off the side, or doesn't it really matter? I do know that in either case, climb milling on that machine is a Very Bad Idea.

Thanks

Carm
03-16-2015, 01:00 PM
Take full depth to the capacity of the machine. If you have good workholding horizontals eat metal. Too bad you don't have two cutters.

boslab
03-16-2015, 01:17 PM
+1, take the full cut, even my little Denbigh horizontal will cut an 1" wide by 1" deep in one go with the right cutter, it's surprising how big a cut they do.
But you soon learn not to climb mill on an old sloppy machine!
Mark

JohnMartin
03-16-2015, 01:17 PM
Full width, full depth. It will bang a bit at the start, unless you ease in from the top or the side. Good reason to make the nuts in long strips.

Toolguy
03-16-2015, 01:44 PM
Yep. It's a bad idea to climb mill even on the heavy duty industrial ones, except for a few that had a special provision for that. You may want to ease into the cut by hand at the beginning, then switch to power feed once you have a few teeth in the cut.

spongerich
03-16-2015, 02:21 PM
Take full depth to the capacity of the machine. If you have good workholding horizontals eat metal. Too bad you don't have two cutters.


AH-HA! Hadn't thought of that. I have a decent stash of cutters... I'm pretty sure that I have 2 cutters that are both plenty wide enough to hog out the width of the shoulders on the nut.

Toolguy
03-16-2015, 02:30 PM
That's why all the different length spacers on a horizontal arbor - so you can get the right space between 2 or more cutters. Make a long strip, cut off lengths on the bandsaw, drill & tap each piece.

Bob Fisher
03-16-2015, 03:01 PM
I would drill and tap in the long strip, then separate. Seems easier to me. Bob.

Baz
03-16-2015, 03:22 PM
Film it. Not enough horizontal working on youtube. :o

Rosco-P
03-16-2015, 03:48 PM
Take full depth to the capacity of the machine. If you have good workholding horizontals eat metal. Too bad you don't have two cutters.

Often called straddle milling. Want to learn more? Forget YouTube, get a copy of the B&S Treatise on Milling, the older the better.

J Tiers
03-16-2015, 09:14 PM
Since you are not that familiar with H-mills, I suggest that you NOT power feed.

Hand feed for a while so you get a feel for the machine, and feed rates with different settings. Then you will know what you can do, and will be able to choose well.

H-mills DO munch metal, but you need to give them the metal at the right rate, or problems will occur. What the problems are, will depend on what gives up first, the feedbox, the cutter, or the motor.

spongerich
03-17-2015, 08:06 AM
Since you are not that familiar with H-mills, I suggest that you NOT power feed.

No danger of that since my power feed on that machine is busted. Unfortunately, the bevel gears are badly worn and skip like crazy. When they show up on eBay, they're usually $180 for the set (ouch!). I need to see if I can find some generic ones that'll work as replacements. I'm thinking that as long as I replace them as a pair, they don't necessarily need to be exact replacements. If the diameter is off just a little, or the tooth count is off by 1 or 2, I'll still have a working feed, even if the "Change-O-Matic" speeds aren't 100% accurate.

Filming it is a great idea. I was already planning to make some videos of my somewhat eclectic machinery collection.
Besides, someone's got to provide new material for all of those YouTube "Fail of the Week" segments.