Chandler Duplex boring heads

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spro
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Chandler Duplex boring heads

Post by spro »

Many of these Chandler boring heads are popping up. Most have had the shank straight now and some are R-8 . It is strange that I haven't seen a description of how they worked. Maybe it is because they don't work or reseller doesn't know. Sometimes they call them "automatic" when they are semi-automatic. The head is set and the slide isn't completely locked. Under power, it bores normally BUT without stopping the mill, the knurled ring is grabbed for a second or more and that advances the slide for the next pass.
Plastikosmd
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Re: Chandler Duplex boring heads

Post by Plastikosmd »

From what I understand you are right for the ones that feed. There may be multiple versions?
Some with auto feed and some without? I see that there is a duplex and a universal. The auto feed sounds similar to a narex or wohlhaupter.
pete
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Re: Chandler Duplex boring heads

Post by pete »

Chandler - Duplex sure sounds like an English made tool Spro. I'm almost positive I've seen that name mentioned in some of my UK written machinist books. If so one of the English / UK forums should or might get you some information.
bjmh46
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Re: Chandler Duplex boring heads

Post by bjmh46 »

Can be used as stated in spro's post, but main function in addition to boring, is facing (think bearing seat shoulder), undercutting, snap ring and o-ring grooves. A beautiful piece of tooling that also has the ability to set tenths. In fact the head is capable of better accuracy than I can measure. Also, to respond to Pete, they were made by the Chandler tool co. of Muncie, Indiana.

Regards
Bob
pete
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Re: Chandler Duplex boring heads

Post by pete »

Thanks Bob, shows what a faulty memory I have.
spro
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Re: Chandler Duplex boring heads

Post by spro »

Gosh fellows, many have been sold recently. When you look at them, with the deep knurling and heavy bevels, you are looking back into American Industry. Gives me a tingle, in a machine way. Then they still work. Not too complex, not too simple either.
spro
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Re: Chandler Duplex boring heads

Post by spro »

I just used mine and didn't really know the model. It is the smaller model "J" using 1/2" shank boring bars. These small ones didn't have a brass plate denoting the model or serial #. These # s appear when the slide is fully open. Mine is #392, under that is "J". I was confused about the slide/limit stop because 90% of them show the limit stop /adjustment in the slide below the rotating dial. That would make sense in boring to larger diameters and stop at set OD. Well mine has the slide opposite and I did find a photo of the same model set that way. I expect the operation manual explains a process by which the slide is removed and installed backwards. Boring bar tool would be set to guide diameter and the machine run in reverse. An example would be a cylinder head with valve guides standing up. They need outside grooves for newer seals or something. A little head like this, bores the groove around the guides and stops at a set depth. That requires the slide to be reversed so there must be a procedure.
spro
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Re: Chandler Duplex boring heads

Post by spro »

The little J head works fine for conventional boring with the slide seemingly reversed. There is 3/4" travel attained by holding the ring. After measuring near the correct diameter, the dial is adjusted to set .001's and the slide locked. It then acts as a regular boring head.
The larger ones are mammoths with automatic features. I wouldn't want to grab a ring over something swinging 8" or whatever, so they had "tommy bars" for that.
spro
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Re: Chandler Duplex boring heads

Post by spro »

Larger automatic boring heads are machines in themselves. The whole mass doesn't swing. They do everything internally. There was a window of time when the J and D were adjusted by the ring, perhaps larger ones too. I have no experience with them but innovation moves forward. Isn't it great that comprehension and engineering moves forwards ? Along the way, the paths set before the newest, are great tools. We rediscover these for a reason and that is great too.
spro
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Re: Chandler Duplex boring heads

Post by spro »

I mean these boring heads and other things were not something everyone had in their basement. This was industry and a machine shop or auto machine company down town or close enough to get that work done. My Dad and other young men at that time built their hot rods, chopped , modified coupes. They always went to Joe or Gill or somebody to get precision boring done. Then they could assemble and make it. Then there are some pictures in an album about good times with the rod . Then they went to war. The old photos wouldn't even be in the album if they had to accumulate all the knowledge of how to bore cylinders or line bore crankshafts or eccentric grinding. They went to old Ken or somebody and that was done. They had the roadster, they built from parts-good parts and had maybe two years of good times. Then f'in war over and over.
gamachinist
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Re: Chandler Duplex boring heads

Post by gamachinist »

The Chandler Duplex automatic heads will bore or face. You can lock the set screw in the dial and the facing head will advance when you hold the feed ring at the top. I have several of them.

Here is a link to a copy of the catalog and instruction pages:
http%3A%2F%2Fwww.scribd.com%2Fdoc%2F26224320%2FChandler-Duplex-Boring-Head-Catalog
If the above link doesn't work, try this one:
https://www.scribd.com/doc/26224320/cha ... ad-catalog
Thanks, Russ


The company went out of business in 2008 or 2009.
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Harold_V
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Re: Chandler Duplex boring heads

Post by Harold_V »

Link is no good.

H
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