Hardinge QC Problems...?

[EmilioG]

I recently purchased a 1/2" round smooth R8 collet directly from Hardinge website store. (I wanted a good R8 collet for my 1/2" shank tools).
I received the collet and upon inspection, Is not what I expected. My 1/2" tools slip right through without the usual grip/spring of my other R8's, including
my other Hardinge R8 collets. I wrote to hardinge about the problem and they quickly sent another 1/2" R8, and it had the same exact problem!

Very odd.

 

[dlane]

Have u tried using it yet, dono maybe new ones tighten up after used, or a bad bach

 

[Alan H.]

I could not quickly find any Hardinge specs on R8 collets via the web. So I got online with Hardinge via chat and asked. The person on chat didn't give me confidence in the answers they gave so I then called their tech service. The gent verified the clamping range as +/-0.002". He also confirmed the collets are still made in New York. Neither the folks I contacted at Hardinge could point me to a brochure or on-line resources with specs. The tech service gent was looking in documents he had there.

By comparison McMaster says the clamping range on their 1/2" collets is +0/-.004". Therefore you'd expect the McMaster supplied collet to fit a 1/2" diameter shank differently than the Hardinge. BTW, I believe you'd receive a Lyndex-Nikken collet from McMaster based on my recent experience with them.

So yes, based on what I found out the Hardinge R8 will fit a bit differently.

In my brief studies this morning on this, I discovered that Hardinge manufactures around the world now. I had falsely assumed they were still exclusively an American manufacturer. Here's an interesting video.

 

[EmilioG]

Thank you Alan. Hardinge makes their BP mills in Taiwan and probably many other tools and machines.
All of the other Hardinge R8 collets that I own have no clamping issues, including a brand new 3/4" R8.
A tool or cutter should not fall out or into the collet opening. Imagine a sharp end mill or an expensive chuck
hitting the floor or cutting your hand, or even spinning in the collet. I no longer have faith in Hardinge. They don't even
understand my concern. Am I missing something? I haven't checked the TIR on the newest Hardinge R8''s, but I was told that it was .0005"
It used to be .0004", Lyndex is .0007" I couldn't find a new Crawford 1/2" R8, so maybe I should settle with Lyndex.

 

[Alan H.]

No, I don't think you are missing anything. I was a bit surprised that they have no written spec they could share. I have both inexpensive and expensive R8's and they generally are not sloppy as you describe.

Do you have a gage pin or two you can drop in that collet to check the actual ID as supplied? My pin collection only goes up to 1/2". From my conversations with them I would expect it to be 0.502" not 0.500".

Alternatively check the actual OD of the tool shank that is loose fitting with a micrometer??

 

[EmilioG]

I've only checked with a .500" ZZ plus and minus. I don't have .502" but I'm sure that is what would hold. My inspection told me that this R8 was .002" over size from their old R8's. A .500" ZZ used, gives a loose sliding fit. The pin drops to the bottom of the collet.
I've also mic'd my tool shanks and cutters and many of them are under nominal size, but not much. Can't recall the actual numbers,
but my other R8's have no trouble gripping them, including my other Hardinge R8's. You should be able to slip a tool into the collet and invert it to insert in the spindle with one hand. A bit trickier when the tool is falling out.

I think Hardinge has dropped in over all quality from years ago and like B&S and others, are abandoning their small tools division in favor of Cnc, Swiss machines, etc... B&S did the same when they became Hexagon and now Tesa Group. Hardinge, it seems is trying to hang on to a bit of it's old glory days while moving manufacturing overseas. I'm not so sure that Hardinge is making their R8 collets in the USA anymore. The finish, heat treatment and grinding look excellent, but the opening/spring clamping is over size.

 

[Alan H.]

Emilio, you mentioned Crawford's. The genuine Crawford are no more unless you buy NOS. I did a study several months ago on 5C collets and ferreted out the story.

Crawford collets were originally made in the UK and have a very good reputation. However Pratt Burnerd now owns the brand and are selling them as PB Crawford. I called Pratt Burnerd and quizzed them. Their collets are made in India. Of course this information is not readily available and is certainly not advertised. I find their pricing is in no way consistent with the Indian sourcing and my sense is that they are clearly farming the Brand.

If I am buying new, I prefer Crawford (new old stock, UK made, limited availability) and Lyndex-Nikken which are made in Japan.

 

[EmilioG]

Alan, I haves several Crawford R8's, NOS and can see the difference in quality with PB branded R8's. (I own two). The original Crawford UK collets are one piece design., PB Crawfords are two piece, pressed threads. The Hardinge R8's are still one piece. If I can't find NOS Crawfords or Hardinge,
I will just buy Lyndex, of which I have two.

I just like to know what I'm buying, but these days, it seems that there is little information that is published for consumers. Lyndex, AFAIK, is still made in Japan, but tomorrow, who knows. I may eventually switch over to a new collet system.