MT3 to R8 Adapter

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Morph
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Location: Oklahoma

MT3 to R8 Adapter

Post by Morph »

I have surfed the web in search of an adapter for the tailstock on my lathe. The tailstock taper is MT3. My mill has a taper of R8. I recently purchased a boring head with a R8 shank. I would like to be able to use the boring head on the lathe but can't seem to find an adapter. I found tons of them for R8 to MT3 but I need a MT3 to R8 adapter.
Perhaps I am just missing something here because of my inexperience, being a newby and all. Any advise would be awsome.
Bill
John Evans
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Post by John Evans »

Unless the shank in the boring head is integral just buy a MT 3 shank and change as needed.
www.chaski.com
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Morph
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MT3 to R8 Adapter

Post by Morph »

That is an excellent idea. I haven't recieved the boring head yet but by looking at the photos in the catalog it looks like the shank does fasten to the head seperately. And they do offer a MT3 shank for boring heads. I am not sure if it will fit this boring head, I will need to contact them and see.
Thanks alot, you saved me alot of time investigating.
Bill
Richard_W
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Post by Richard_W »

I have one question for you.

When it's so easy to bore from the tool post. Why would you need to use a boring head in the tail stock on a lathe?


Richard W.
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Fender
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Post by Fender »

Agree with Richard. Look for an Aloris-style QC toolpost and use a boring bar holder.
If you plan to do much boring in the lathe, especially for larger holes (> 1"), you might want to look into getting some MT3-shank drill bits. They will hold much better in the tailstock than drills with a turned-down cylindrical shank in a drill chuck, and you can rough out a hole much faster than by boring.
Dan Watson
Chattanooga, TN
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Morph
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MT3 to R8 Adapter

Post by Morph »

This is sort of embarrassing, you see I am just now acquiring tools to be able to bore. I have never done it before, lol.
But I am guessing that I really will never use the tailstock for boring as long as I have a descent tool holder for boring bars on the tool post?
I ordered a QCTP set sized for my lathe, I believe it has a tool holder for boring bars.
Bill
Richard_W
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Post by Richard_W »

We have all been there, even if it has been 40 years ago and hard to remember back that far.


Richard W.
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Morph
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MT3 to R8 Adapter

Post by Morph »

I am just now 42, does that mean in 40 years I won't remember this?
I'll never make it that long, the first 40 was rough enough to get through, lol.
But I look forword to trying.
Bill
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Fender
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Post by Fender »

Bill,
I've been messing with lathes for almost 40 years, and what is discouraging is, I still don't know that much. :?
But basically, the tailstock is primarily used for two things: supporting the right end of long workpieces (like an axle or shaft) with a center, and drilling or reaming. I guess a third thing would be to support a boring bar between centers when the workpiece is mounted on the carriage. You wouldn't do boring from the tailstock because the tool would deflect too much. Boring on a lathe is usually done from the toolpost on the carriage.
Dan
Dan Watson
Chattanooga, TN
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Morph
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Location: Oklahoma

MT3 to R8 Adapter

Post by Morph »

Dan,
thanks for the tips. I really do appreciate the time you all take to guide beginners such as myself. Their are alot of good people on this forum.
My tooling is scheduled to arrive today. I am sure to find more questions once I attemp to do some of the things I've been dreaming about for so loooonnnggg.
Bill
kvom
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Post by kvom »

While boring is best done with the toolpost, you can use a boring head in the tailstock to turn tapers. You just need a center mounted in the head, and use it to offset the workpiece. This is a lot easier than offsetting the tailstock.
WmRMeyers
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Re: MT3 to R8 Adapter

Post by WmRMeyers »

Kinda hate to revive this thread, but I'm looking for the same thing, except that I have a Smithy CB-1220XL that my brother bought for me. I suspect it's his way of telling me he wants me to make some stuff for him. ;) It's not for the tailstock, however. This thing has a milling head with an MT3 spindle, where the lathe spindle is MT4. I also have a mini-mill with an R8 spindle so have some R8 tooling already, and would like to share them. Also have a lathe (used to be two lathes) with MT3 spindles, so have a fair amount of MT3 tooling, as well. Also Drill press and horizontal milling machine with MT2 tapers. Be kinda nice to be able to swap stuff around as needed. I have considered making my own. So far I've not been able to make a decent MT3 external taper, but I have roughing and finishing reamers for MT2 and MT3 sockets. I have a couple of tanged MT3 to blank arbors, and a tube of high strength loctite...

Anyone had any luck finding such an adapter?

Bill in OKC
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