What's new
What's new

Best metal removal method for manual mill

DanBrub

Aluminum
Joined
Feb 14, 2019
Location
Tennessee
I have a 9x42 Enco mill (sure ain’t no K&T!) but I have a job requiring me to mill a channel in 1018 that is 1.25” deep, 2” wide and 6” long. I’m wondering what recommendations you folks have on the fastest method to do this material removal on my “light duty” mill.

Thx
Dan
 
Nibble away at it with a rougher mill at modest RPM after clearing as much of the bulk as possible simply chain drilling. Start with some short flatted shank drill bits make chips. Even drilling you're probably better off with speed on the low side say 40 SFM and heavy feed with water based coolant.
 
I have a 9x42 Enco mill (sure ain’t no K&T!) but I have a job requiring me to mill a channel in 1018 that is 1.25” deep, 2” wide and 6” long. I’m wondering what recommendations you folks have on the fastest method to do this material removal on my “light duty” mill.

Thx
Dan

How many do you have to make?

What tolerance do you have to hold?

Is it a pocket in a piece of stock, if so what type of corners are required, or is it just cutting a channel that is open at both sides/ends?
 
I can eat alot of metal with a roughing or corn cobb cutter and spray mist or coolant flow to clear the chips. Thats on mills like yours put in low back gear I could run that depth and if the side wall finish/tolerance allows you you can leave it as is. Those roughers come in different pitches, a fine one leaves a decent wall smoothness.
 
On light duty machines you're generally better off with a smaller solid carbide or indexable endmill with light depth of cut and high feedrate if you want to get it done as fast as possible. I used to use a ¾" Seco on a Bridgeport all the time. It could generally handle ⅛"-¼" depth of cut about as fast as I could crank the handle depending on material.
 
I'm in the chain drill and corncob rougher camp. Pocketing is hard to get the chips out, your best bet is a plexiglass shield and an air blow gun. Rig the air blow to keep the chips away from you, and run it as much as your compressor will allow. For a turret mill, 3/4 diameter is large enough, either the drill or end mill.
 
Will try to answer all. As for tooling I have hss roughing end mills in 3/8” and 1/2” and 1/2” carbide 4 flute end mills. I don’t have flood coolant but do have mist. I need to make 6 of these. Tolerance is +-.010 the channel is open on both sides so no corners to worry about. I had considered the chain drilling but had not convinced myself that is a good option so thx for that confirmation.
 
drills are going to be faster . stab them in and go . then clean up w/ endmills . the drill is the most efficient way to remove material. when you return to mill the slot , you'll have a fraction of the chips
to deal with. the cuts will be interrupted, but the cut won't clog.
 
Open on the ends? Stand it upright and drill from each end. Do it right and part of your waste falls out in one chunk.
 
Not as elegant, but how about using one of these?
392b12297d0735b47514ec79e77ff46f.jpg


Sent from my Nokia 7.1 using Tapatalk
 
Since both ends are open I am thinking multiple rotary saw blade cuts then finish up with an end mill.
 
I have had good results with plunge milling such with an end cutting 4 flute stepping over and plunge the next down feed all the way for the length of the channel with leaving .020 at the bottom for clean-up. Then conventional mill the sides with seeing in the width to spec.
I would use and end mill holder with an angle whistle-stop and a double piggie back) set screw so the end mill could not pull or back up.
Did this for milling die pockets that had very close spec for place and depth.

End mill end primary 8 to 12* (10*) with one flute to center.
 
If OP has a vertical bandsaw, clamp em to a angle plate and cut out as much as possible. I’ve found sawing first then milling removes metal fastest.

L7
 
When it works, nothing removes material faster than a saw. But you still have to drill a corner sufficiently large to turn your blade 90 degrees so you can cut out the bottom.
 
Funny you should mention using a saw. These parts have triangular corners on two edges along the 6” length. Legs of triangle are 1” and 1.344” so angles are approx 36 and 53 degrees. I cut these out with my Ellis metal saw. Couldn’t orient the part to get the 36 degree so had to set up for the 53 deg cut...unfortunately saw only gets to about 50 degrees but saves a lot of time getting that much material removed! Don’t have the correct blade as most of my work is 11 gage tubing so it was slow going but still faster that trying to mill it away. Holding the part was s challenge but got it done.
 
Buy the bandsaw blade you need for this job.
Bandsaw cut down one side.
Chain drill and slot the other side wide enough to to fit the bandsaw blade.
Bandsaw across the bottom to the other bandsaw cut.
Mill the bottom and sides to size.
 
If OP has a vertical bandsaw, clamp em to a angle plate and cut out as much as possible. I’ve found sawing first then milling removes metal fastest.

L7

yep 1/2 mill near one side use my roll in to make the 2 other cuts while milling the next slot in the next part for the saw. prep all the parts then go back to the mill set up for all the clean up milling
 








 
Back
Top