Cleaning Up A Jt33 Taper (not Specifically Atlas)

louosten

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Greetings to All...

I just pulled a Jacobs 6A chuck off a vintage drill press to replace with another that had a locking collar (similar to a Jacobs 33-34c). I used the #6 wedges from Jacobs and after heating up the chuck with a hair dryer, it came right off!

My dilemma (not urgent) is to clean up this chuck and keep it for a spare. When the chuck was clear of the spindle, I notice it, and the spindle had been gouged...must have slipped in a previous life; the chuck wasn't running exactly true, and this may have been a contributing factor:

chuck1.jpg

My question is simple...is there a JT33 hone, or something I can acquire to run down into the chuck to clean up the surface? I was able to clean up the spindle by careful filing, and finishing with oiled emery paper. The new chuck went on with no problems.

Any advice would be helpful; thanks in advance!
 
I would polish with Emory cloth, then use some lapping compound and lap the two together, then clean real good and reinstall on the press. The lapping will insure a perfect fit.
 
Silverbullet;

The lapping idea definitely has merit. I've done this before on bronze seacocks on my sailboat, where you want a real close fit (i.e. no leaks!). They call it 'intimate lapping' when the two working pieces are brought together against a thin film of lapping compound. My issue is that I wouldn't want to re-lap a perfectly ground male MT33 with a boogered female MT33. I'll have to find a substitute, like an older MT33 male arbor that could be used.

While I was surfing the Web, I also found the following item for sale:

JT33_Reamer2.jpg

Not real cheap at $65, but if you're making custom arbors or adapters, or cleaning up older ones, it will be helpful, and pay for itself over time...
 
knock off any of the burrs on either taper, carefully sand down with some fine grade wet'n'dry and leave it at that. As long as the majority of either taper is good, the odd depression or gouge won't make the slightest difference.
 
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