3mt to Straight shaft adaptor.

[Lazurus]

Does anyone know of a supplier where I can get an 3MT to a straight shaft adaptor? I want to fit a pigtail (available in various shaft sizes) probably a 3/4" shaft onto my lathe which has a 3MT headstock. I have no metal working facilities so need one out of the box as it were. I can then fit various buffing wheels onto said pigtail adaptor for final polishing.

 

[novocaine]

use a drill chuck.

 

[Rorschach]

Look for a morse taper blank end arbour.

 

[Rorschach]

Like this

https://www.ebay.co.uk/itm/RDGTOOLS-3MT ... Sw44BYPYak

 

[SteveF]

How small does your lathe chuck close down to?
I have in the past just stuck pigtails in my chuck

Steve

 

[AES]

Yup, I have one on my female threading tool (die stock) for my (metal) lathe. Can't remember where I got it from, but 99% sure you'll find what you want at Arc Eurotrade. Just the MT/straight adapters, without tool holder (see sticky in Metal Working Section). Good, honest, efficient company, sensible prices. Usual disclaimers.

AES

 

[chaoticbob]

Pigtails with a 6mm male shaft, which can be accommodated in a drill chuck as per novocaine's suggestion can be had eg here. I often use one on those in the chuck on a drill press.
If there's some reason specific for wanting a pigtail with a female mount (of the type which are usually designed to fit on the spindle of a bench grinder or similar) and you can't find a ready-made adaptor, turning down one of the soft MT arbors referred to earlier is literally a ten minute job on an engineering lathe. I'd be happy to do that and send it for the cost of the arbor +postage if you've got no-one local with the kit.
Rob.

 

[Inspector]

Look for Morse Taper End Mill Holders.

http://www.arceurotrade.co.uk/Catalogue ... ll-Holders

Morse Taper Collets could also work.

You could also get an ER Collet Holder.

You'll need a drawbar of some kind to keep the MT from vibrating loose.

Pete

 

[Lazurus]

Thanks guys, I find the drill chuck in an adaptor has a nasty habit of working loose in the head stock so wanted a better solution. Will have a look as suggested on the above links.

Thanks

 

[Lazurus]

Look for Morse Taper End Mill Holders.

http://www.arceurotrade.co.uk/Catalogue ... ll-Holders

Morse Taper Collets could also work.

You could also get an ER Collet Holder.

You'll need a drawbar of some kind to keep the MT from vibrating loose.

Pete

The end mill holders look ideal, how can I tell what the bore is, is it as per the advertised size, I take it the thread is the draw bar thread size? Sorry if being dim.........

 

[Inspector]

Bores are very accurate and the stated thread is for the draw bar. Keep in mind you are putting buffing wheels in it and not end mills to hog out a lot of metal so the accuracy doesn't have to be perfect. Is the light glowing a little brighter?

 

[Lazurus]

Thanks Boss Got it now lol.

 

[Robbo3]

The cheapest way would probably be a Morse Taper collet although you'll still need a draw bar
- http://www.arceurotrade.co.uk/Catalogue ... er-Collets

If you want complete sets then an ER chuck & range of collets are available from Axminster, Arc Euro, Chronos & other engineering suppliers.

 

[Inspector]

Robbo I suggested both, just didn't link them. I figured he could search the site since I put him in the vicinity and gave him the terminology. :wink: No matter what he choses to use he will need to make a drawbar or they will all come loose. The only way to get on without a drawbar would be to buy an ER chuck that threads on to the shaft like the Beall chuck. More money but the most versatile arrangement.

 

[Lazurus]

Thanks Guys, I have found what I need. The draw bar is negated as the pigtail has a hollow in which to put the tail stock live center so wont be going any where. much appreciate all the advice.

Stuart

 

[Lazurus]

Ok so another question, why do some Morse taper adaptors and tooling have a tang and some do not. The 3MT Jacobs chuck I use I had to cut the tang off as it would not fir in the head stock, it was fine in the tail stock which I assume is milled similar to a pillar drill shaft. But the head stock has a 3mt bore but shorter..... Sorry more info required. lol

 

[novocaine]

the tang is for removal using a drift. (someone will be along shortly to tell you it's for drive, that isn't correct)
if it doesn't fit in your drive, it maybe a B22 which is the small end of a morse taper.

anyways, 3 types of morse taper, tang, flat and threaded. this is of no help to you at all though. did you try rotating it to see if there is a tang receiver in there?

 

[AES]

Agree with novocaine, that's what I was taught too. There is OFTEN (not always) a slot in the quill (female), shaped to take that tang, so as novo says, did you (before pushing it fully home) try gently rotating it to see if it suddenly "popped" further in? If so, your quill does have that slot, but as above, many machines don't, that's why you can buy them with and without tang (and also why a lot of people cut the tang off, it's normally quite soft, not hardened like the taper portion).

BTW, I don't want to teach Granny to suck eggs, but EVERY time you remove and replace a MT (e.g. fitting and removing a drill chuck into the tail stock on a lathe, or tooling on a mill), you should wipe the male part off with a CLEAN rag/tissue/fine brush, and ditto, up into the female bore. Although hardened, a small bit of oily swarf hanging on (or hiding up the bore) when fitting a MT WILL leave a minor indentation on the female bore (it's a good trick to look for scratches & digs in the female bore when buying any SH machine tool - shows how careful the previous owner/s were/not).

HTH

AES

 

[CHJ]

Ok so another question, why do some Morse taper adaptors and tooling have a tang and some do not. The 3MT Jacobs chuck I use I had to cut the tang off as it would not fir in the head stock, it was fine in the tail stock which I assume is milled similar to a pillar drill shaft. But the head stock has a 3mt bore but shorter..... Sorry more info required. lol

The Head Stock spindle machining would have assumed you would be using a Short Taper with a threaded socket to take a Draw Bar for security.
Using a Morse Taper fitting in a Headstock without a Draw Bar is only Safe for Between Spindle use where the Tailstock is providing safety support to ensure it stays in place, any Morse taper that is being used to drive tooling that is not protected against coming adrift with tailstock or positive pressure to keep it engaged can be dangerous, at best it will just stop driving and fall out, worst case though is that it can spin out with the centrifugal force in ever growing circles and be ejected at speed.

 

[chaoticbob]

Perhaps not directly relevant to the OP's quest, but it might be worth noting that screw-in tangs are available for MT arbors designed for use with a drawbar - eg here.
I find these handy for for drill chucks - the same chuck/arbor assembly can be used on the mill (drawbar, no drift slots in the quill), drill press and lathe tailstock - for which either type would do, but the tang makes the arbor 'self ejecting' when the tailstock quill is wound right back.
Rob