Tapping Head- making one??

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Mosey

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Is it possible (for a novice like me) to make a tapping device for tiny taps..something with a clutch to prevent breaking small taps?
I can't afford a Procunier or Tapmatic, at least at the prices I see.
I now use a spring-loaded holder in the drill press or mill. Still able to break them.
 
Mosey,
I'm not all that sure my points are even worthwhile since I've never used one of those tapping heads. But I personally think those heads are more of a production tool than something for a home shop. My tap breakage went down to pretty well zero once I started using top quality HSS taps. Greenfield and OSG would be just two brands I can at least personally say are really good. And probably because I'm wanting dead true alignment on critical items, I do it the long slow way and drill and at least partially tap each hole as their drilled. Unless you've got a high end and very repeatable DRO, It's pretty tough to get everything back to that true alignment by drilling all the holes first and then go back and tap each one.

But I also have to think machine tapping would give you better finished and closer tolerance threads than hand tapping. So it's kind of a better/ not better situation depending on how you look at it.

To build one? I dunno. Pretty complicated to get it all figured out for a clutch type system along with the auto reverse function when changing direction on the quills spider. Just my thoughts and there worth a lot less than you paid for them.

Edited to add, Like any cutting tool, Taps and dies do get dull. Unless your properly set up to resharpen them with something like a Quorn T&C grinder. You need to make the tough but logical decision to replace those expensive taps and dies when they get dull. It's the "just a few more" that generally gets you a broken off tap and a problem to save the part situation, And where that brand new tap all of a sudden starts looking really cheap.

Pete
 
How much tiny?
You can try with olive oil mixed with sulphur.
Another tip: close tap in a mandrel or, better, in an ER a little slipping... and turn very slow..
 
I have been using Balax forming taps for awhile now, some down to 0-80. I use a purchased tap holder with the sliding shaft on top. They go into the mill or drill press chuck and slide up or down to take up the length as you go. I use a tapping lubricant, either Tapmagic or Edge lube, and usually work in aluminum. Occasionally they break, seemingly without notice. I wonder if they get fatigued? I just hate the chips and backing out with conventional cutting taps. I guess my error may be not keeping them perfectly aligned with the hole axis, or what?
Some of the work is in 1" cast aluminum plate that I picked up from a friend. No idea of it's composition, but it is hard and brittle. Maybe I should use it for spacers and not engine parts.
I also have a Starrett ratcheting holder, but it doesn't float vertically.
 
Thread forming taps require a different hole size than the taps that actualy cut the threads. You are using the correct and recommended hole size for those taps? Your actual composition, alloy and after casting ageing and heat treatment of that cast aluminum may not be correct for thread forming taps. But I'm just guessing at that.

Pete
 
The holes are right off the Balax chart, and when in doubt, I go .001" larger. It's cool how these pilot holes seem too large, until you run the taps in, then voila! nice threads.
Composition of the materials may be the problem.
 
I can't comment on making one but I bought a "cheap" Chinese made one - but I have yet to try it out properly...
It was on e-bay and is still there as a Buy it now type sale http://www.ebay.com/itm/ws/eBayISAPI.dll?ViewItem&item=390100425740

Its the smallest size as I see myself tapping hundreds of small holes in the (near) future but not so many larger ones...

Anyways at ~$140 plus shipping it was much less than a name brand and I couldn't find negative reviews for it (which is a rarity in itself..)

Hopefully my shop will be back together soon and I'll get to use it.

Mike
 

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