Crooked draw bar threads in arbor

[Silverbullet]

I'd send it back or ask for a refund. With proof at times they just refund rather then return. The cost to ship may be more the the cost of it new. So if you do keep it. I'd bore it out to the max at the base of the taper , then I'd make a plug and I'd braze or silver solder it in and drill and tap straight. If you don't think it's strong enough pin it before drilling and threading , soft pin of course. That way it couldn't pull out .

 

[Tozguy]

I have never torqued an MT taper draw bar very tight. It just needs is to be snug. I would expect that for a 3/4'' deep plug glued in with strong Loctite would hold enough.

 

[Bob Korves]

I have never seen a drill chuck arbor before that is threaded...

 

[Ulma Doctor]

Yes it is from BB. I get lots of good stuff from them but this is an exception. I bought it for $8 to make a ball center. For that it is fine.
View attachment 239992
The tapers are very good so I may even put a drill chuck on it eventually.
Its not worth the trouble to return it and I would rather take on the challenge of fixing it anyways, even if it is just for laughs. If I do get a good chuck for it then it could hold the arbor and make any drilling or boring of the draw bar end possible. (using a collet, 1/2'' stub, drill chuck, arbor, with a steady rest somewhere on the arbor). Then bore out and glue in an insert as suggested above.
Thanks for your ideas gentlemen.

Hey Tozguy,
i haven't used a ball center and have no idea of what you use a ball center on and how you would use it.
pardon my ignorance, but can you shed some light?

i like your spirit. in taking on the challenge, we'll all learn things we didn't know before!

 

[Tozguy]

Bob, as I wrote earlier there is very little need on a lathe for me to use a draw bar with it. Maybe for a drill press or other machine it would be necessary? I have no use for one with a tang either for that matter.

Mike, my project is to taper a 24'' rifle barrel by offsetting the TS centre. There would be some slight rocking on both centres because of the off set. Some folks use a ball center for this so I'm giving it a try.

I'm still working out the set up but this is the general idea. Will show pics next time.

 

[Bob Korves]

Bob, as I wrote earlier there is very little need on a lathe for me to use a draw bar with it. Maybe for a drill press or other machine it would be necessary? I have no use for one with a tang either for that matter.

I haven't seen a drill press with a draw bar, but they may exist. Some people, who want to use a drill press as a milling machine, would like that idea, which would still be a poor one. The tangs, while not intended for it, help to prevent the taper from spinning in the female taper, though they can and do twist if the torque is high enough. Their intended use is for pushing the taper out with a drift working sideways in a slot. The slots are common on MT adapter bushings and on some tail stocks, unfortunately not on mine. The tangs are usually softer than the rest of the tool, and can be filed on.

 

[Silverbullet]

I haven't seen a drill press with a draw bar, but they may exist. Some people, who want to use a drill press as a milling machine, would like that idea, which would still be a poor one. The tangs, while not intended for it, help to prevent the taper from spinning in the female taper, though they can and do twist if the torque is high enough. Their intended use is for pushing the taper out with a drift working sideways in a slot. The slots are common on MT adapter bushings and on some tail stocks, unfortunately not on mine. The tangs are usually softer than the rest of the tool, and can be filed on.

Bob on the m head there used and the atlas mill , and many of the foreign mills use them in mills many larger tapers . China makes lots of them for morse taper.

 

[Bob Korves]

Bob on the m head there used and the atlas mill , and many of the foreign mills use them in mills many larger tapers . China makes lots of them for morse taper.

Milling machine, yes. I have seen them with MT and draw bars. The original poster was talking about drill presses.

 

[Silverbullet]

Milling machine, yes. I have seen them with MT and draw bars. The original poster was talking about drill presses.

As a newbie he probably didn't know the difference in the arbors . In fact there's a post about making the flats up with threads to put on arbors for mills so they will work in tailstock and drill spindles.

 

[Tozguy]

Bob, as I wrote earlier there is very little need on a lathe for me to use a draw bar with it. Maybe for a drill press or other machine it would be necessary? I have no use for one with a tang either for that matter.

Milling machine, yes. I have seen them with MT and draw bars. The original poster was talking about drill presses.

As a newbie he probably didn't know the difference in the arbors . In fact there's a post about making the flats up with threads to put on arbors for mills so they will work in tailstock and drill spindles.

Fact is that my MT3 - JT6 arbor came with a draw bar thread. I know some about arbors but not so much about every machine that exists that such an arbor may be used in. Sorry if that led us off on a tangent.