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Morse taper dropping out

STEVEMORSE

Plastic
Joined
Aug 10, 2019
Hi all I have an opti mill. When milling my Morse taper collet chuck appears to be vibrating loose. During the install I use the draw in rod to pull it up and the tighten it firm but it may last only 15 mins before it starts to drop and disengage. When this happens I notice th draw in rod at the top is loose ( not pulled up firm ). I have done a good job of securing my work piece. Is there a link for a proper set up procedure of this nor a YouTube vid ?
 
Hi all I have an opti mill. When milling my Morse taper collet chuck appears to be vibrating loose. During the install I use the draw in rod to pull it up and the tighten it firm but it may last only 15 mins before it starts to drop and disengage. When this happens I notice th draw in rod at the top is loose ( not pulled up firm ). I have done a good job of securing my work piece. Is there a link for a proper set up procedure of this nor a YouTube vid ?

You need to sort out more stable drawtube holding. Obviously. Scant other option. Might be an easy fix, but a need to modify is more likely.

The reason it struggles is not new.

A discussion ran heavy in the trade journals, late 1800's. Brown & Sharpe's works manager, Oscar J. Beale - pen-name 'jarno' - a major contributor.

Bottom line is it became well-known that a Morse taper was well-suited to drilling, where the force is on the long axis, yet the tools could be gotten out of the spindle with not a lot of hanging-up.

B&S taper was not good at drilling, because it DID tend to hang-up, become hard to remove.

Morse was found unsuited to milling. side forces cause it to want to work loose.

B&S taper worked fine for milling, had much less tendency to walk loose.

Oscar - (at and running B&S ) - "Jarno" taper contribution to the mix is a compromise, elegant more in its dead-easy derivation math as much as its utility, so it only saw limited adoption of any kind.

"Opti" - when choosing Morse taper for a mill, just overlooked what was solidly established by 1890 if not earlier is all. Morse for drills, B&S for mills. (NMTB..CAT, BT... HSK... Capto.. all came MUCH later).

"Those who do not learn from history..." etc.
 
I would not recommend milling with a MT as THERMITE explains.
Never have I, but if I were I would take it very easy, lite cuts.

You could also modify the key, which may help, but the above still applies. I have done this for MT shanks that fit loose or are worn, by TIG welding the key a little, just adding a little rod, then grinding to a better fit. Have had MT shanks that liked to fall out during drilling and tapping before, this fixed the problem. Look for wear spots on the key, dycum the key and slam it up there and see where the wear is.
 
I would not recommend milling with a MT as THERMITE explains.
Never have I, but if I were I would take it very easy, lite cuts.

Morse taper works acceptably(but not perfectly..) in highly sought-after mills like Deckel FP1 so it's not end of the world if the mill happens to have morse taper tooling.
 
Hi all I have an opti mill. When milling my Morse taper collet chuck appears to be vibrating loose. During the install I use the draw in rod to pull it up and the tighten it firm but it may last only 15 mins before it starts to drop and disengage. When this happens I notice th draw in rod at the top is loose ( not pulled up firm ). I have done a good job of securing my work piece. Is there a link for a proper set up procedure of this nor a YouTube vid ?

.
many try a type of spring washer or lock washer but obviously vibration can be quite strong at loosening things up. you might just need to limit not doing heavy cuts with a morse taper.
.
other problem with morse taper is depending on drawbar pressure it can vary quite a lot pulling tool holder into taper. quite common to vary .005 or .010". i have also seen where machine put excess pressure on tool and it got pushed into morse taper over .010" further into taper. even when tool released from taper with difficulty and put in normally then you really see the difference in position as it pushed into taper with difference amounts of force
 
Make sure your drawbar isn't hardware store threaded rod. Given your location, I'm guessing you want grade 10.9. If inch based thread, you want grade B7. Second solution would be to add Belleville washers under the drawbar. You will have to go with what you can find, but they can be combined in series to increase travel, parallel to increase force, or both.
 
OK, I'm reading this a bit differently. He says he uses a "draw in rod" but it becomes loose. I'm hearing "draw bar" when he says "draw in rod".
Possibly the drawbar is a replacement made out of something stretchy - like all-thread or not too hard steel? I've run into this before. A replacement made of drill rod made all the difference.
 
OK, I'm reading this a bit differently. He says he uses a "draw in rod" but it becomes loose. I'm hearing "draw bar" when he says "draw in rod".
Possibly the drawbar is a replacement made out of something stretchy - like all-thread or not too hard steel? I've run into this before. A replacement made of drill rod made all the difference.

Agree the concept, but if his one is the same sort of "Opti" as this one?

YouTube

Might be better advice he just goes and finds some heavy metal drum music and gives the "mill" up?
 
The lucas boring bar we had at work used morse taper tooling and had a cross lock pin in the quill that used a taper key. Worked fine but would be difficult to do with bearings near the end of the quill.

Dave
 
The lucas boring bar we had at work used morse taper tooling and had a cross lock pin in the quill that used a taper key. Worked fine but would be difficult to do with bearings near the end of the quill.

Dave

Quite common on hor-bores.

My larger MT5 drillpress has the same dual-azure system as well (Alzmetall AB5/S)

"Best of both worlds" in that the MT taper-angle is known for rarely jamming, and the key makes for solid lockup that doesn't load the taper for driving torque - only for accurate centering.

Mind I don't OWN any drills that are slotted to match. Only rationale I can figure on a drillpress would be to lock-on an extension bar for working down inside deep box or cup shapes.
 
You might check the tool and the spindle.
Make sure they mate well.
It could be as little as a chip in the socket.

Yes! This was my first thought; either a chip, or an incorrectly ground morse taper.

My second thought: what sort of vibration are we talking about, and why is it there? Is this chatter at the cutting tool? If so, fix your speeds and feeds. Is it something out of balance in the spindle itself? Definitely need to fix that. Maybe it is due to a large fly cutter or some other tool that is inherently unbalanced. If so, may be trying to use something larger than the mill can do.
 
Yes! This was my first thought; either a chip, or an incorrectly ground morse taper.

My second thought: what sort of vibration are we talking about, and why is it there? Is this chatter at the cutting tool? If so, fix your speeds and feeds. Is it something out of balance in the spindle itself? Definitely need to fix that. Maybe it is due to a large fly cutter or some other tool that is inherently unbalanced. If so, may be trying to use something larger than the mill can do.

Listen - even with yer eyes closed - to that you Tube video I linked.

If that is what the OP has, he's plucked.

Wasn't sure there was even a tool in the nostril, and there wasn't even any material on the table, let alone a cut underway.

Seemed a known-mode failure, motor, VFD, or both.

Unless it is meant to be an electric demolition hammer? Mill-Drll-pavement-breaker.. so as to be able to dig its own grave?

Clever people, these <ethnics>. Eliminates freight costs for warranty service.
 
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Hi all I have an opti mill. When milling my Morse taper collet chuck appears to be vibrating loose. During the install I use the draw in rod to pull it up and the tighten it firm but it may last only 15 mins before it starts to drop and disengage. When this happens I notice th draw in rod at the top is loose ( not pulled up firm ). I have done a good job of securing my work piece. Is there a link for a proper set up procedure of this nor a YouTube vid ?

Better/tighter draw bar is the first thing that comes to mind. Nothing wrong with allthread, it's what I use on my toy Emco FB2 mill, probably about the same HP as your Opti (IOW, very little).

Never known mine to come loose, usually it's a shit of a job getting the tooling *out*. I hate Morse taper milling machine spindles.

If a better/tighter drawbar doesn't do it, I'd be looking very suspiciously at first the shank of the tooling and checking it against a *known good* MT drill sleeve, followed by doing the same check on the mill spindle.

This thread is going to be locked because that's a home hobbyist toy machine and pretty much bottom end of the range in terms of capability even there so don't be surprised and don't bitch about it when it happens. There's a machinery discussions sticky that explains this in detail.

PDW
 
I would not recommend milling with a MT as THERMITE explains.
Never have I, but if I were I would take it very easy, lite cuts.

You could also modify the key, which may help, but the above still applies. I have done this for MT shanks that fit loose or are worn, by TIG welding the key a little, just adding a little rod, then grinding to a better fit. Have had MT shanks that liked to fall out during drilling and tapping before, this fixed the problem. Look for wear spots on the key, dycum the key and slam it up there and see where the wear is.

"Key" ?????
 
"to the padded cell", Doug.

"Attempted milling" with a #2 MT is prima facie evidence of insanity.

My Hauser Jig bore has a MT-3 with drawbar, and there is no "Key" of any sort.

So I would like to understand what post #4 is about.
 
My Hauser Jig bore has a MT-3 with drawbar, and there is no "Key" of any sort.

So I would like to understand what post #4 is about.

Why would you expect any such of a thing?

My Alzmetall AB5/S - 5 MT - drill press DOES have (provision for) a key. Wedge type. Same-same many horizontal boring mills. NO provision for a drawbar, though. Passage is blocked by a surplus of steel Alzmetall left lying about for lack of any better place to park it. Go figure.

:)

But neither one is a milling machine, nor ever claimed to be.
 








 
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