Maho mh700 - how can i identify the spindle taper?

My maho mh 700 has a female draw bar. I need help identifying the taper so i can order some collets.

any help is greatly appreciated

Thanks

Rich

Depends which era MH700 you have.
The 60's/70's "rounded" types used either MT4 or ISO40. MT4 won't have the drive dogs of the ISO40 so it should be easy to tell.
If it's a later "square" machine I think that they were all ISO40 but that's not my era!

Charles

That machine has MT4 spindles, both vertical and horizontal. The drawbar is for the S20x2 buttress thread common on the Deckels of that vintage. I think I would replace the draw bars and go with something like this:

MT4 Shank ER32 Chuck With 11 PC Collets Set | eBay

-Alan

Thanks guys
I think i am going to get some mt4 collets with the buttress thread.
i don't want to give up the headroom with the er 32 chuck.
did any one ever use the s20x2 adapter that screws into the female drawbar and makes it an m16 male?

lectrician1 said:

Did any one ever use the s20x2 adapter that screws into the female drawbar and makes it an m16 male?

Click to expand...

I have used plenty of S20x2 adaptors that have an M16 thread and screw into DIN 69871 tooling. These are used with the S20x2 drawbar. I have never thought of fixing the adaptor into the drawbar (loctite) and then using that with different DIN 69871 tooling. I don't see any reason that it won't work.

I never thought of that, either.

But in the US, with a lot of access to CAT40 or MAS-BT (or whatever) tooling, it could be a great idea.

But then one can't use any S20x2 tooling, ever (at least not without the hassle of removing the drawbar).

Cheers
Erik

Dude your post is extremely confusing and very hard to follow. He would have no reason at all to be cutting S20x2 female threads, so why are you talking about that? His machine already has drawbars in it like the one in your ebay link, so no, he does not need to be buying anything like that. What he is proposing is to make a male to male adapter with S20x2 threads on one end which he would locktite into the drawbar. The other end could be M16 or 5/8-11 male thread. I've seen MT4 collets available with either thread. Sounds like a good plan.

adh2000 said:

Dude your post is extremely confusing and very hard to follow. He would have no reason at all to be cutting S20x2 female threads, so why are you talking about that? His machine already has drawbars in it like the one in your ebay link, so no, he does not need to be buying anything like that. What he is proposing is to make a male to male adapter with S20x2 threads on one end which he would locktite into the drawbar. The other end could be M16 or 5/8-11 male thread. I've seen MT4 collets available with either thread. Sounds like a good plan.

Click to expand...

I don't want to confuse him so just rid of my reply.

For MK4 tooling, the Deckel doesn't just adapt. For SK40 it does. Maybe that is different for the Maho.

I'll sit back and watch the thread progress.

At least if the idea is to use the tooling, the actual taper may need to be cut down, it's not plug and play, AFAIK. It was stated by 2 people above that it was MT4. At least my Deckel won't just let you plug the S20x2 plug in like Bruce does, AFAIK that only works with SK40. Bruce stated DIN 69871, those are 40 taper based.

That's a good point. He would have to get a MT4 collet and see if it bottoms out on the drawbar. If it did I'd just pull the drawbar and make a new one, not that hard, rather than cut the end off all the collets.

Found these on ebay



I found these on eBay. I wonder if they will fit

The overall length is 122mm. I measured my spindle from the drawbar to the spindle nose, it only measures 114.5 mm
It seems like the collets will be too long by about 6mm

lectrician1 said:

View attachment 202096

I found these on eBay. I wonder if they will fit

The overall length is 122mm. I measured my spindle from the drawbar to the spindle nose, it only measures 114.5 mm
It seems like the collets will be too long by about 6mm

Click to expand...

Not sure if those are the right thing or not, if they are you need an adapter to use them. I personally have a complete set of those both inch and metric but only use when absolutely necessary, I don't think they grip very well and have seen tools pull right out of them.
I regard to your original post; if your spindles are MK4 it needn't be a problem providing you have the capability to cut 2MM pitch threads. I have turned and cut the buttress thread on #4 Morse tanged shanks and and boring head adapters so they fit as original with no loss of head space. Personally having machines with both 4 Morse and ST40 taper spindles I prefer the Morse taper for a few reasons. That all changed when Deckel/Maho added drive lugs to the spindles but that is a completely different topic.
Dan

adh2000 said:

That's a good point. He would have to get a MT4 collet and see if it bottoms out on the drawbar. If it did I'd just pull the drawbar and make a new one, not that hard, rather than cut the end off all the collets.

Click to expand...

You'll either need to trust me on that or just wait for lectrician1 to try it, but it's not plug and play. If it was I wouldn't have cut down and adapted a non-replaceable Wholhaupter UP3 to add the thread. The one I cut down had a tang though.

I don't believe the plugs will allow you to use the tooling from the U.K. with M16 thread for a draw bar. Unfortunately, that doesn't work. You would need to cut the taper down and re-thread it for M16.

lectrician1 said:

I found these on eBay. I wonder if they will fit

Click to expand...

Yes, they will, if you have the sleeve as Dan mentioned. The sleeve will allow you to use these single-lip style collets, which suck IMO, as the sleeve gets stuck in the spindle easy. In that regard, the original MK4 taper with S20x2 thread on them work the best between spindle collets and stick down less to provide the most headroom on your Z axis. Same with the single lip collets but you need to deal with the sleeve. One note, be careful on the Alexander style collets on ebay.uk, I'm not sure they will work in a Deckel/Maho, they look slightly different.

The collet chuck is not a bad solution (I have 2, ER40 and ER32 both of which I bought from Singer). Providing the same tooling works on your Maho that works on the Deckel, you can get the collet chuck from Singer with the S20x2 thread on it (about $100 plus shipping). Otherwise you'll need to adapt either an M16 or 5/8-11. I also have plugs which are S20x2->5/8-11 and you can deal with those on an inch machine by tapping/threading 5/8-11 on the tool end and thread it in with loctite. You still need to cut the taper down, most tools are only hard for the thickness of the surface, but all vary. Tapping that crap is not as easy as one would hope, in my experience. I have a Wholhaupter I've done it to on an MT4 shank. Single point may be easier on the lathe.

Lastly, you could fabricate a new draw bar to replace the captive draw bar, but I don't know if that would work. There would need to be enough room inside the spindle to shorten it up, and my guess is there's not enough room.

Good luck on your decision, you have a few choices, non of them are plug and play, however.

Cheers,
Alan