What is high speed machining

[HuFlungDung]

Chill, Camminc,

A cart is designed to be pulled by a horse, and not a horse to be pulled by a cart. Quite a common idiom, actually, but maybe not where you're from

Scott_bob was just meaning that he should worry about getting a controller that is capable of accurate high feedrate, before he begins to worry about a 40,000 rpm tool vibration.

[Scott_bob]

Camminc,

Give me passion anyday...

I respect a guy with an opinion. Really...
Frankly, it's a wellcome change around here. When I first came to this site I thought we (the community) could have a healthy discussion. This has not happened IMO. It takes more than a few paragraphs, way more than a few sentances to get an opinion out there and be understood.

To you points about Dynamic Feed Compensation, they are pretty well laid out. I don't know a lot about this technology as I'm sure you can tell. I think a lot of us here would like to hear more. Be patient, remember I don't have the data you have.

Best regards,

[camminc]

Scott-bob: Hi, this is Randy. I am not here to hassle anyone, I am here because I care about the subject of discussion. I don't know much but I do know alot about frequency analysis, shrink fit and tool holder balancing. I apologize for any attacks upon you or anyone else, This this type of discussion is what it takes to get attention on these forums, cause a stir, get emotions up. Of course there will be skeptics and that is good, it will energize us all to look a little deeper to find answers. l simply do tooling and that is what I know, I have seen millions of dollars spent on controllers, programming software and programmers but it still does not maximize the cut where maximizing tooling does as they fail. It is an awesome feeling to go against a million dollar machine with a laptop computer against all their support of programming and engineering and kick some butt. Mouths wide open, faces in despair when it happens, shock as they experience it. Only a few submit though. I am sick of programmers being put on a pedestal while people in the shop are really doing things. It is a terrible problem for us all to venture and it happens every where in the US and it is sad to see, our great country with no unity in machining practices. The Europeans are using this technology and kicking our butt as we speak, we need to catch them or they will pass us. They seem to catch on better.

The cut is controllable by knowing frequencies, which enhance motion of the controller and cpu being used, it all works together, not against each other as it seems everyone wants to make it because of tunnel vision. The cart you speak of also carries frequency control, without it the cart is only half full of tricks, either in front of or behind, it does not matter. Machinist, programmers, engineering, management, must realize and submit, that all their great knowledge is not enough alone, combine technology, work together, don't shut out the little guy in the tool crib that does frequency analysis, for he is on your side. He just might surprise you. I was taught this stuff by PHD’s as a tool and cutter grinder / presetter / purchasing, just by luck, a dumb ole tool and cutter grinder, I have no masters degree, no AA degree, but everywhere I go I see no engineers that can not do what I do with this stuff because they don't apply. Most wash there hands of it simply because they think it is difficult to learn and do, no one carries the ball. If it was so difficult then how did I, a simple man ever get the hang of it? They prefer to sit in there chairs making big bucks because management thinks they do it all, analyzing things, engineers doing their engineering thing, while I am out there making it happen. I get no support from them where I go, because of antiquated ways. Only a few actually take it in and reap the reward of doing so. Only a few open their eyes and submit, that there could be another way to approach this. Read the articles on my site, see the savings made by companies, who take the step. Let there testimonies lead the way.

[Scott_bob]

Camminc,

You're not helping your cause by venting your frustration. The data from your technology would be better served by discussing the the benefits of the technology not your experience along the way. We are not here to understand your frustrations...

The title of this thread is:

What is high speed machining...

What do you say we just stay on that topic.

[hardmill]

I have had access to all the nice little toys you speak of
Cam and in my opinion their "NICE". Thats it.
You can get the same job, material, machine, holders,and
even operator and I can guarantee it won't run the same
next time. I would much rather an operator have working
knowledge of problem solving then having someone come
out to floor everytime we change parts or tools.
Machining is ever changing and one who works on the floor
knows that. To say that this little gadget or this little trinket
will do the trick is insane. Your train of thought sounds more
to me like that of an engineer, This is right and that is
final."WRONG"
With better than 20 exper. on the floor, programming , planning,
designing tools I'd put my skills against any contraption.
And I do work in the engineering dept of an aerospace co.
Don't get me wrong I am educated and very well versed in the
understanding of harmonics and their effects on tooling.
But generally to acheive the vibration reduction we are speaking
of you need to slow down, due to the fact that the machine tool
can't handle the speed or feeds to get over the hump where
the harmonics are reduced. The tools you speak of are nice and
I imagine they have their place, but employers want their product
out today.

Thank You for your time

PEACE

[Bloy2004]

On the contrary, I'm enjoying every aspect of this discussion!
continue!!

Klox..did you ever imagine what your initial question would foster?

[hardmill]

Glad your enjoying yourself.
Thats what this forum is for , Discussion.


And dancing..

PEACE

[Mike F]

It's good to see a little passion out there - someone who believes in what they are doing but it is probably true to say that we need a balance of both, experienced machinists and new technology, to move forward with both accepting the other has something to offer - without either having a blinkered approach (another horse, cart analogy)

History (experience) teaches us many things, one of which is the way forward - we need that union of old and new.

Mike

[Scott_bob]

I honestly ask myself the question:

Are our CNC machines capable of HSM?
What defines High Speed in Steel or harder materials is not High Speed in Aluminum if you're talking about just speeds and feeds.

Camminc, I don't know what data you'd get from your analysis that would discriminate between material that is Rc55, then I suppose you'd have to get a new reading when machining softer material say aluminum right?

The dynamics would not be the same with different material right?

Another thought, If I wait until I get chatter, or audible signs then when finishing with a .062 diameter ball end mill, my experience would suggest that the end mill is no longer any good. Quite often we are finishing with even smaller ball end mills say .032, what then?

Just for clarity, Our data proves that it is the limitation of the CNC control that prevents us from HSM feeds even for steel materials.
Accurate, smooth feeds above F30. inches per minute are not possible. No amount of speed / feed rate compensation can move us to the level of HSM performance. I'm not even talking about aluminum material where feed rates should be above F300. for true HSM.

Sincerely,

[Gunner]

Just to throw another wrinkle into the discussion, I noticed no one has mentioned the addition of high pressure coolant. I've seen some amazing displays drilling stainless steel with coolant thru drills on a Mori machining center. 70 - 7/16 holes to a 3" depth in under 3 minutes with the use of high pressure coolant.
Normally when you try beefing up speeds and feeds your common flood coolant isn't enough to keep heat from being generated at the cutting edge. The heat contributes to premature breakdown of the coatings or material of the cutting tool. High pressure coolant breaks through the vapor barrier created at the contact point of the cutting tool and the material allowing the tool to stay cool. This allows you to acheive higher spindle speeds and feed rates and gives you the extended tool life to go with it. Lets face it, it doesn't make much sense to make a part faster if you have to keep stopping the machine to change tools. A good friend of mine owns a small job shop in the area and purchased a machine based on this demonstration. He has been extremely happy with its performance. Because he has the high speed machining capabilites he has been able to keep a step ahead of his competition and has stayed above water financially during the rough times most of the other shops have just gone through.

Gunner

[Scott_bob]

So true...

High pressure coolant is one of the other words that get watered down, a lot like HSM does...
What I mean is this: Our Fadals have pressure in the neighborhood of 40 psi delivered by a pump running on 110 volts thru 3 nozzles.

We are upgrading to a multistage 220 volt pump that puts out 150 psi and we have machined a new nozzle manifold with 6 high pressure coolant nozzles (that cannot be whiped out of their dirrection by stringy chips from drills). We have to redesign the Fadal circuitry to up the voltage to 220 from 110 volts.

The point is this: Even with all this upgrading (3x the psi and gpm), this is NOT High Pressure Coolant. It's just good coolant pressure and directional control. I knew we would be breaking tools is we did not have good coolant delivery when we get our new HSM control next week. I can hardly wait...

High Pressure Coolant is 1,000 psi and up...
If you can get this kind of pressure thru the spindle, that is awesome. We use thru the spindle coolant at the low pressure level and get dramatic feed and tool life improvement...

Thanks Gunner for bringing this up!

Sincerely,

[Gunner]

Scott_Bob
If you ever get a chance to see a high pressure coolant demonstration, do it. It's very impressive. I believe they measure flow by gallons per minute not psi. My problem is I deal mainly in CNC Lathes. We have experimented with this technology on our Miyano's and although it did work it became expensive. The high pressure coolant would eventually infiltrate our main spindle bearings which caused some unexpected rebuilding. We run about 500 psi on our Emco 332 for our thru coolant blocks and tools. It helps but is not as effective as true high pressure.

Gunner