[Dan B]

Does anyone work with heat shrink tool holders? Is this the preferred method for speeds above 12,000 RPM?

Any insight would be appreciated.

Thanks

Dan

[Scott_bob]

Yes, they are the best...

This technology is getting cheaper too, competition is bringing the prices down, every one of the holder suppliers is offering their own.

We use this unit:
http://www.shrinkfit.com/package.htm

works great!
increased feeds by 30%
increased tool life by 70%

Carbide only though, so if someone puts say an Inserted End Mill holder in one of these, you won't get it out easily.
All is not lost though, you can pressurize the cavity between the tool and the retension knob by filling it with oil, then heat it up. Messy though...

You should check out the shrink fit stuff by Iscar...
cheaper yet and modular...

Scott

[Dan B]

Thanks Scott.


Dan

[tschuett]

I feel pretty strongly that the Haimer shrink units are potentially best because of the computerized cycle time for inductive heating and because of their refrigerated cooling. Total cycle to heat and cool to room temperature is about a minute and a half to two minutes. I was recently in a shop that bought a cheaper inductive unit and it overheated the holders, distorted the taper, and left the holders on the bench to cool over 20 minutes. The long cycle time makes it more costly to use by wasting time. The potential damage to holders also increases operating cost. In addition, I have a safety issue with hot holders setting out.

[tschuett]

An afterthought to my last post...

Scot is absolutely right about increased tool life and performance gains. Accuracy and finish also improve a lot.

The potential economy of the modular systems is interesting, but for optimal performance when practical, I think a direct shrink fit in one-piece holder is best to minimize inaccuracy and to maximize rigidity. Modular is good, but one-piece still seems optimal to me.

The Haimer shrink machine has one other worthwhile feature. It's programmable heating allows use with the OSG and Teknara holders made by MST. Their stainless steel alloy seems troublesome for other inductive units. That flexibility for all makes of holders helps make it a sound investment.

[Scott_bob]

tschuett,

How is the price of the Haimer system, Is there a website?
Can they do HSS tools?

One other really nice thing about shrink fit:
No set screws! No flats to grind on the shank of a tool.
And as long as the diameter of the shank is the right size (I've never found one u/s) these shrunk fit holders will never let go of your tool, never...

Not with the 360 degree clamping force they exert...

Scott

[tschuett]

Scott:

The Haimer system is a bit pricey at $12,000, but I know several using it and they all love it; no regrets. It's a one-shot investment that you can buy and use with pleasure. It will change your taste in workholding.

Yes, it will do high speed.

The factory in Germany is www.haimer.com. The USA operation is located here in Addison Illinois and their site is www.haimer-usa.com.

Their holder prices are quite good and once in use, you won't mind having paid the price for the shrinker.

[Dan B]

It is the Haimer unit that we are looking at. We were quoted a price of $12,500, which sounds about right.

I was impressed with the refrigerant cooling system. After about 90 seconds, the tool and holder were back to room temperature.

Dan

[Klox]

Dan B,
It's the first time i hear of heat shrink toolholders....hmmm interesting!
Tell me more, as i am a novice on this concept...

Klox

[HuFlungDung]

We're sorry, Dan B is busy serving other customers. Your inquiry is important to us. Please stay on the internet, for the next available agent.



Hi Klox,

First, they made a batch of toolholders that came out of the grinder with the hole too small. Then, some wise guy decided, if he built an induction coil to heat the thing up, it would expand enough that he could quickly shove the cold endmill in it. Voila, a new product. Then, they proceeded to sell these second grade toolholders as if they were something new and exciting. Phooey, and they charge you extra for the goof-up.

[Scott_bob]

Huflungdung,

do i hear you right, you are not a believer in the advantages of shrink fit holders?

Scott_bob

[BIG AL]

Don't mean to rain on anyone's parade, Folks this is a vary old method of fitting parts togather. I first became aware of this method durning my days in aero-space maching, putting helocopter short shafts togather. If you don't want to spend a ton of money and just have a little fun, Get a blank tool holder bore it under size to the tool you want to mount (you have to play with going under size here). Think this out now, our goal temp is 50 to 60 below 0 dec f. We can get to that and below with dry ice or for those of you who have access to a bottle of nitrogen,regulator, some plumbing, a container like and old ice chest you are there. "Don't forget some heavy gloves". And did I say have Fun?

[Klox]

LOL (X10)!!
Thanx Hu, you have brighten up my day! One more question: Can the holder be used more then once? (when the shivering endmill breaks, LOL!)

Klox

[Dan B]

Hi Klox,

The holders apparently can be heated and re-heated up to 5,000 times before the bore starts to elongate.

As for the concept, I agree that it is not new. We used to shrink mold inserts with dry ice 25 years ago. In fact heat and cold have been expanding and contracting things since the beginning of time. Nothing new about the concept. However, being able to expand the holder in 3 seconds, place the tool, then cool it in a minute or two seems pretty time efficient to me. I've seen them in operation on the Hermle machine, and it seems like a good idea.

HuFlungDung,

What would you recommend as an alternative to heat shrink, for high speed machining?

Dan

[Klox]

Dan,
the advantage of this type of holder would be (i presume?): to hold the cutter "better", prevent cutter to chatter and keep it from coming loose at high spindle speeds.....

Klox

[Dan B]

Also, to eliminate runout. The shrink fit tools we checked on the Hermle were running out less than .0001" at the cutter tip.


Dan

[HuFlungDung]

Hi guys,

No, I think heat shrink toolholders are a good idea. I'd use them if I had need for them. I was just speculating on how the first instance came to be

I can imagine these are easy to assemble, not so easy to remove? The smaller the shank, the tougher it is to gain the expansion differential for disassembly?

[Dan B]

Hi HuFlungDung,

From my observations, they disassemble just as easily as they assemble. They had no problems removing a 3 mm ballnose cutter. Just make sure you grab the tool with a welders glove on, or you will get seriously burned.

Dan

[tschuett]

Guys:

i'm like a reformed smoker on this topic. i thought "who the hell wants a hot holder around? too unsafe and too long. Then a tool salesman said what's wrong with you? you get 4 times cutter life! Then i met Haimer and saw under 2 minutes to heat, unload, load and cool. That made it fast and safe. The tool life improved as described, but better, the deedrate, finish, and accuracy improved too. I'm German and I lived in Missouri (briefly), so i had to see it. Today i'm convinced! Simple physics says heat shrink is really cool!

[tschuett]

sorry, i missed the close quote after "around?" and misspelled feedrate as deedrate. apologies! long day!