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Powder keg

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Not model related, But Machine shop porn non the less:O) 1045 steel.

[ame]http://www.youtube.com/watch?v=Sebko0n6uJ0[/ame]
 
Man, thats kicking it in the butt.

I bet the poor guy making that part has to make 10,000 of them and got sick of taking all year to do it. I know whats it like to do the same part for months on end so you get up to speed where the you are scaring the metal off.
 
I've been accused of scaring the metal off before:O) We have a CNC that's new to our shop and I've been pushing it to see what it is capable of:O) Flipped a part out of the vice the other day
icon_yikes.gif
Better slow it down a smudge:O)

Wes
 
Love those vids.

You'd never believe it, but at the recommended parameters for their web site he's running:

- 4500 rpm
- 600 SFM
- 0.0079" feed per tooth

It's a 6 fluted end mill, BTW. Their catalog says this bad boy cutter is $84, which would seem ridiculous to the average HSM, LOL!

Some things to note:

- He does an interpolated hole (that circular cut at the beginning) to minimize engaging the whole cutter. Most of the pocket cut is done with no more than half the cutter in the material and the rest of the cutter is cutting air. This lowers cutting forces and gives the cutter more time to cool in the air. It also helps clear chips. Recutting chips is the biggest enemy in these things.

- The corners will be where he gets the most stress on the cutter and machine rigidity. I can't tell it's going so fast, but a lot of CAM programs will automatically slow down the feeds in the corners for that reason. They'll compute how much of the cutter is engaged with material versus air and work it from there.

- No coolant. It's all air. The chips are blowing out blue. Many of the sales reps for milling cutters are saying turn off the coolant above 400 SFM--the chips carry away the heat (no, I don't want another long discussion on that please!). Note that this doesn't work on lathes: the cutter is engaged for a full revolution and never gets to cool. Dry machining is a lot touchier on lathes, and also on drilling operations.

HP requirements here are less than you'd think: 2-3 HP. That's too much without a real VMC weighing a couple tons though.

Now that was steel. Aluminum really flies!

Cheers,

BW
 
Great video Wes!

My company has just recently started to use the high speed end mills from Iscar.
Thursday last week was my very first experience with one.
The part called for a 3/8" wide groove in the face 7/8" deep.
Cutting that with a grooving tool would have been difficult.

Our programer handled this one because it was way over my head!
A 3/8 high speed end mill was programed to plunge into the face 1/8" then the
chuck would rotate 360 degrees. It would plunge 1/8 again, etc until it reached the
finish depth. 2500 RPM on the mill spindle with the chuck rotating at 4 RPM.
It performed perfectly!

A coworker has a phrase, "You couldn't pull a needle out of his a$$ with a tractor."
That would have been ME watching that process run for the first time! :D

Rick
 
Rick have you ever done any plunge milling? We had a job milling 347ss for gas turbine exhaust struts that had to have about 80% of the original burnout removed. We tried everything. Our original program was using a 2" button cutter milling .05" doc and it was burning up inserts very quickly. The plate was 2-1/2" thick. I think it may also work for heavy material removal on a manual mill but haven't done it myself yet. Most of your machining pressure is done in the Z axis so the machine hadles it well. We also did most of this machining dry except for drilling and the final finising ball mill. I always heard that you shouldn't mill stainless dry , but it worked very well.
 
Tooling capabilities daily.
Some of those changes are mind boggling.

With the high speed cutters, coolant is a no no.
The high speed cutter need the heat at the cutting point to perform,
yet they remove the stock so quickly that heat is on the chip, not in the part.

Up until now plunge milling was a 40 fpm, coolant flooded HSS end mill.
Now it's a 250 fpm dry cutter.

For an old dog, such as myself, those changes are pretty intimidating.
With an old style end mill some ER doctor would be picking pieces of hardened steel out
of your forehead. Now you press Cycle Start and the watch the tool do exactly what the
manufacture says it will do. Even is SS they work perfectly.

For me it's a difficult learing curve.
The parameters set go completely against every machining experience I've learned over
the past 30 years.
I push that button and expect the world to explode. LOL
It doesn't...

Rick



 
rake60 said:
The parameters set go completely against every machining experience I've learned over
the past 30 years.
I push that button and expect the world to explode. LOL
It doesn't...

Rick
And how about that climb cut? That was the quickest way to a butt-chewin' when I was in machine shop class...
 
tattoomike68 said:
Now days CNC mills rarely do anything but climb mill unless they are cutting through flame cut hard skin like AR plate or T1.

Mike's statement is totally TRUE!
Climb cutting is the preferred method on a CNC machine.
Keep in mind that a CNC gets it's speed by taking lighter cuts at much quicker recovery times between
passes.

Climb milling with an end mill will result in a better finish with less tool wear.
It does require a snug gib adjustment and COMMAN SENCE!

If your milling machine gibs are sloppy and you start into a cut climb milling cut the end mill cutting
pressure will pull the table into the cut and things will get ugly very quickly.
If your machine can not be adjusted to accept those pressures PLEASE be intelligent enough to accept
that fact! Hand polishing a milled surface is far better than having to spend a bunch of money repairing
a machine, OR paying the deductable on your health insurance!

No finish or speed of machining can ever be worth the risk of getting hurt!!!!
This hobby is about making things to show off and be proud of.
I'd preferr to see picture of a hand with all the fingers attached and in working order holding those
finished engines, taken by the clear vision of two undamaged eyes...

This topic is of the new style industrial age.
At home things are much different!

Be SAFE guys!!!!!!

Rick

 
Just saw that this last week. Been watching this stuff to understand how fast the move the handles on my 60 year old mill. :) Here is what I think is the same machine with 6061.

[ame]http://www.youtube.com/watch?v=uAcBU2iqkKE&feature=related[/ame]

That is what I call cookin with fire.

Kenny
 
I would be pretty worried about a plugged up cutter in aluminum that deep and that fast with no coolant.
 
AllThumbs, Because of the RPM, I'm guessing around 4K. They are actually taking a lighter cut than you would on your mill. so they don't have to worry about the mill clogging up.


Wes
 
Tight gibs or lead screws? On a shop full of clapped-out WWII machines run by generations of high-school hotrodders? Come on! ;D The piece used by the instructor to make his point about climb cuts was a 1-1/4" horizontal mill arbor w/a permanent bow, & the workpiece w/a trail of divots across it where it was pulled out of the vise...I know the finish a climb cut gives, I tend to use it as a very light finish cut on the mill, very carefully...
 
Oh I know but that doesn't prevent me from worrying about it!

Eric
 
AllThumbs said:
Oh I know but that doesn't prevent me from worrying about it!

Eric

Eric all new things are scary when all of your past training tells you it's wrong.

Everyone here needs to understand these end mills are a radical new design.
It is NOT safe to run a standard end mill at these speeds!

Rick

 
rake60 said:
Eric all new things are scary when all of your past training tells you it's wrong.

Everyone here needs to understand these end mills are a radical new design.
It is NOT safe to run a standard end mill at these speeds!

Rick

I have seen these machines in action...very sweet. I have no past training, so that's not the problem for me! ;D

Luckily, all these CNC machines are enclosed with interlocked doors, so when the part comes out of the vice, it doesn't come flying across the room at you. makes a big noise mind you....

Eric
 
LOL

While my instincts would also expect to see a part flying out of the vise,
I have never seen or heard of that happening.

Amazing as it may be, sometimes the engineers nail their objective.
These new products work.

Safety is Paramount! If this technology is something you can not feel safe with, then
by all means, don't try it!!!

In 1920 it took an average of 2 hours to broach a 1/2" keyway in a shaft.
Today it takes 12 seconds using a new high speed end mill.

No one should ever attempt to force those changes on anyone.
The tools and technology to do that are available, but if your head tells you
it's unsafe, the it IS unsafe for YOU!

No machining process should ever be attempted by someone who does not
completely understand it.

For everyone here.
If you need to do something that you've never done before and the set up or
process feels dangerous to you, please ask about it here before you try it!
Many of us here have done it wrong already. We were lucky enough to get
away with it. You can learn from our mistakes, but the only way for us to
help is if YOU ask!

There are NO dumb questions.
Getting cut or hurt because you didn't ask IS DUMB!

Rick


 
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