JT33

Let' say that you have a spindle with a JT33 *male* taper. It will take a chuck (duh!)

What if you want to use it to hold an end mill - are there attachments that would do that (the spindle is *not * hollow so drawbars etc are out)? What about other attachments - could you, for instance, make it to take a pulley?

I have seen one person who drilled and bored a hole in the spindle to mount

6 mm end-mills but that seems like cheating :-)

It seems to me that anything not held on by a drawbar or other means is going to get ripped off the spindle while milling but I do not know enough about this to say with any certainty.

Reply to
Michael Koblic
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You're right to be wary and the need for a drawbar (or something to lock in a collet/end mill). This topic often comes up on RCM when people want to use drill presses as milling machines. Many drill presses use Morse tapers to hold drill chucks in the spindle. When the chuck on such a drill press is side loaded, it can become unseated and cause injury when it spins out of control. If you look through the RCM archives for "taper + side + loads", you will find many discussions with warnings advising against this.

Reply to
Denis G.

The problem with milling in a drill press is not only one of the chuck getting loose, as this could be fixed with a retaining screw as on reversing drills. This might work for very light milling.

A greater difficulty is that on most drill presses the bottom spindle bearing (nearest the chuck) is designed primarily for end-loading, ie. thrust from drilling. Side loading from milling may very well cause chattering or rattling of the spindle/endmill, depending on type of bearing.

If space or budget is a problem the most satisfactory solution is probably a post-type mill since these are now quite inexpensive. These will drill very well and are not too shabby for milling, if the loss of registry during head elevation change is acceptable. On these machines the quill is adjusted to depth-feed the cutter; typical quill feed range is 5" or so, any more would require head elevation change.

This issue has been debated at great length in this group and the general consensus has been "don't do it!"

Wolfgang

Reply to
wfhabicher

I got that but it is a separate issue. FWIW the same person solved (?) this problem by changing the bearings in his drill press. However, the details are sketchy at best.

Right now I am purely trying to determine what the JT33 will support. Right now the only thing I am coming up with is to stick a JT33 chuck on it, chuck a round stick in it and put a pulley on that stick. That way one could drive other weird and wonderful contraptions but it seems inelegant and "umstandlich" (the Germans often have a better vocabulary as well as engineers :-).

Reply to
Michael Koblic

Why not just put the pulley on a spare motor? or do you have a fascination with Rube Goldberg? Gerry :-)} London, Canada

Reply to
Gerald Miller

As a guess, I'd say any spindle that dosent have a through hole isn't intended to take a milling cutter. Are we back to "milling on a drillpress" again???? ...lew...

Reply to
Lew Hartswick

Open the top cover and use a 2nd belt in one of the other grooves on the front drive pulley? --Glenn Lyford

Reply to
glyford

Of course! Once a simple solution is pointed out it seems - simple :-) I shall certainly look at it with that aspect in mind. Thanks.

Reply to
Michael Koblic

Why did *he* build a Time Machine? No, I am more Jara (da) Cimrman person (you gotta be a Czech to get that one, sorry, see here for further reference:

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Seriously, though (why now, says he...?), I like the fact that I have a motor and a bunch of pulleys all in a neat package giving me the ability to change speeds without having to re-do the whole thing.

I know I must not use it for milling 'cos that would be bad...:-)

Reply to
Michael Koblic

From Wikipedia - "A Rube Goldberg machine is a deliberately overengineered apparatus that performs a very simple task in a very indirect and convoluted fashion" Gerry :-)} London, Canada

Reply to
Gerald Miller

If you drop the word "deliberately" the description is probably accurate. "Deliberately" would imply some sort of intent based on knowledge which I do not possess :-)

Reply to
Michael Koblic

Instinct??? Gerry :-)} London, Canada

Reply to
Gerald Miller

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