Hardinge HV-4N Question

[talvare]

I would like to get opinions from the experts here concerning a Hardinge indexer. I have a HV-4N indexer with both the Hardinge tapered nose spindle and a 2 3/16-10 threaded spindle that I am considering finding a 5" chuck for. What are the advantages or disadvantages of one spindle type vs the other for use on an indexer.
All input is appreciated. Thanks.
Ted

 

[L Vanice]

Threaded spindles had been in common use for decades when, in 1904, Franklin Hardinge applied for a patent on his tapered spindle nose that could drive tooling in either direction and provide a precise and repeatable mounting. Here is a link to his patent, in which the advantages of the taper mount are described.

Patent Images

In practical terms, either system works well enough. Hardinge still sells all their 5C spindle nose tooling for either taper or threaded mount. In economic terms, used Hardinge threaded tooling is cheaper and more plentiful on eBay than the taper mount tooling.

I think I have some Buck 5" Ajust-Tru back plates with both mounts and some Buck 3-jaw chucks that I would sell.

Larry

 

[talvare]

Larry,
Thanks for the response. I suppose for use on an indexer either type of mount would work fine as you shouldn't have to worry about a threaded chuck unscrewing itself as is possible on a lathe. Recently I have been watching eBay for these chucks and so far, anything that looks decent seems to command a pretty steep price. Since my indexer is used pretty infrequently, I'm starting to question whether or not this would be a smart investment. I also have a 10" Walter rotary table that it would be nice to use the same chuck on and it seems that it may be easier to fabricate a mounting system for it with a chuck that utilizes the threaded mount. I need to put more thought into this, but I may interested in one of your chucks and/or back plates.
Thanks again
Ted

 

[stephen thomas]

As Larry notes, the choice might boil down to economics.
I prefer the Hardinge "4 degree" taper and have never found it difficult to make back plates and such to fit them.
However, among the 8 or so Hardinge 5c spindles here (dividing heads, indexers, lathes) a few threaded versions crept in. Besides those, all my 4c stuff arrived threaded spindle.

It would be great not to have to duplicate things like back plates, faceplates, integral mount chucks, and all the various size & depth closers for pot chucks. If you use pot chucks and closers on an index or DH, there is little worry about unscrewing. However, don't be blase that a jaw chuck or back plate won't unscrew when milling, or sometimes heavy repetitive drilling - it definitely can if you don't pay good attention to the direction of forces when setting up for an op. More so, even, than on a lathe, for many milling ops. Of course even with the taper mount system, it is worth paying attention to the cutting force direction and chuck setting direction.

IME, taper mount tooling is more common. Other people in other areas of the country might have different experience.

smt

 

[Jim Caudill]

I think I have some threaded chucks left over from my HC days. If you think you want to go down that route, send me a PM.