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Timo
07-06-2008, 12:23 PM
I have an early 80ís JET 12Ē X 24Ē lathe. It has a 2 ľĒ - 8 spindle nose. The manual states a #4MT spindle taper. The taper extends 2 3/16Ē into the spindle nose. Iíd really like to get some collets for the lathe so Iíve been searching the forum threads for information. I know that there are several Set Tru collet chucks available but I would like to get the type of collet holder that mounts directly into the spindle nose itself. The ER system appeared to be what I was looking for. I found lots of information about the collets themselves but not too much about the collet holders. I checked MSC, ENCO and several other catalogs for what collet holder I would need, but they didnít seem to spell that out, maybe I missed it. My SHARS catalog, (page 64) did show a chart that had the different shank/taper sizes and their corresponding ER collet series. So if Iím reading it correctly I need the MT4 shank collet holder and the ER-40 series collets; plus Iíll need to make a 5/8Ē-11 drawbar. After Iíve read this it almost seems a little silly to ask, but have I missed anything?
Thanks, Tim

jeep534
07-06-2008, 02:35 PM
check tallgrass tools http://www.tallgrasstools.com/ER-32ColletKit.html

archie =) =) =)

Timo
07-06-2008, 04:42 PM
archie, this won't fit my spindle nose, plus I'd still like to be able to use the spindle nose taper to hold the collet closer. Thanks for the reply.
Tim

mendoje
07-06-2008, 05:17 PM
Correct, the Tallgrass unit wont fit your spindle, but IMO this is the approach you should take. If you go with a milling type collet chuck that uses a drawbar, then you will not be able to feed stock all the way through the spindle. With the tallgrass approach, you have a collet nosepiece which threads onto your spindle, and onto that you have the ER type collet closer nut. This is a very common design for a collet chuck.

Most likely, you will have to make the nosepiece, but if you can cut internal and external threads, and tapers, you can make it. An ER collet chuck closer nut can be purchased separately. However, the way to go is to purchace a complete MT4 ER40 collet chuck set, which would include a full range of ER40 collets, the MT4 shanked collet chuck, the closer nut, and the wrench. Take the collet chuck and put it way or set it aside. Make the collet nosepiece as I mentioned, and use it with the closer nut and wrench that comes with the set and you're done. I suggest ER40 (instead of ER32) because it has 1" capacity, more in line with the size of your spindle. What to do with the MT shank collet chuck that comes with the set? Well, if your tailstock spindle is also MT4, then use it there, along with the collet nut and collets, to hold drill bits much more accurately than a drill chuck. If your tailstock isnt MT4, then just purchase whatever MTxx ER40 collet chuck set that is appropriate for your tailstock.

Jeff

derekm
07-07-2008, 03:43 PM
here is an alternative again using an ER40 pass through lathe collet chuck

http://i298.photobucket.com/albums/mm242/derekm_2008_photo/colletlathe.jpg

This one was purchased from chester UK and it allows the full 26mmlink (http://www.chesteruk.myzen.co.uk/store/er_lathe_collet_chucks.htm) for about $80. It needed an adaptor plate making to fit the nose of my lathe (an obscure taper bayonet) which I made out a a slice of cast iron on the face plate. You can see in the photo I 've also got an ER40 MT3 chuck for the tailstock and my mill. This is showing a 2mm drill going into a 12mm diameter workpiece which will eventually become the speedo trip zeroing knob for a Kawasaki KH400.

I didnt want to use the MT4 collets because I couldnt then use a the through spindle for stock. I also wanted to use the same collets (and reuse the investment in collets) for the tailstock(MT3), Drill press (MT2),my vertical mill head (MT3), Dividing head(Int 40) and horizontal mill (Int 30). Thus I needed to span 26mm (approximately the spindle hole size) to a few mill and 4 types of connection. This was the ideal solution for me. If it seems familar its because its almost the same as old tiffies

TGTool
07-07-2008, 11:22 PM
archie, this won't fit my spindle nose, plus I'd still like to be able to use the spindle nose taper to hold the collet closer. Thanks for the reply.
Tim

Tim,

You're getting good advice. The ER40 adapter can be built on a larger hex stock base. I've made some ER-40 adapters on larger hex's and I'll see if I've got something to fit your spindle. If I have, I'm open to selling just steel, drawings and steel, the whole thing or whatever works for you.

Alternatively you can get a length of hex stock from a steel supplier and the nut and wrench for any of the industrial suppliers - I usually use J&L. If you machine it to your spindle, with a good fit for the register, then turn the collet cavity in situ, you can't get better accuracy and repeatability with anything else.

Jan - Tallgrass Tools

Timo
07-08-2008, 08:53 AM
Jan, Iím sure Iím getting good advise. My problem is Iím having a hard time visualizing all of it. I guess Iím not the sharps knife in the draw, plus it sounds like some of the machine work might be beyond my capabilities at this point. Thatís why I wanted something that would just slip into the spindle and Iíd be good to go; albeit, short stock only --- thereís always the 3 jaw.
Tim

derekm
07-08-2008, 09:08 AM
Jan, Iím sure Iím getting good advise. My problem is Iím having a hard time visualizing all of it. I guess Iím not the sharps knife in the draw, plus it sounds like some of the machine work might be beyond my capabilities at this point. Thatís why I wanted something that would just slip into the spindle and Iíd be good to go; albeit, short stock only --- thereís always the 3 jaw.
Tim

You could always just start with a MT4 to ER40 collet chuck, some collets and a piece of M16 all thread rod and a M16 nut and you are good to go with short stock. Then you could progress to doing the other things with the collets later.
A MT4 ER40 collet chuck and collets can be had very cheaply from ebay shops. All of the jobs I've done so far with my collet set could have been done with just that set up.

TGTool
07-08-2008, 12:33 PM
Jan, Iím sure Iím getting good advise. My problem is Iím having a hard time visualizing all of it. I guess Iím not the sharps knife in the draw, plus it sounds like some of the machine work might be beyond my capabilities at this point. Thatís why I wanted something that would just slip into the spindle and Iíd be good to go; albeit, short stock only --- thereís always the 3 jaw.
Tim

Tim,

This is a section of the adapter, in this case an 1-1/2 - 8 to an ER-40.

http://i48.photobucket.com/albums/f244/TGTool/ER-40Adapter-1.jpg

In your case you'd use 2-1/2" hex instead of 2". You machine the internal thread to match your spindle as shown on the left. Remove it from the chuck, remove the chuck and thread your hex onto the spindle. Now do the external thread for the nut and the 8 degree taper for the collet.

If you have doubts about fitting the internal thread, make up a dummy like your spindle nose and make sure it will screw into your existing chucks. Then you have a test gauge as you do the threads on the adapter.

Timo
07-08-2008, 07:46 PM
Jan,
Itís amazing how a picture can make things so much clearer. Thanks. By the way, how do you attach a picture to a post. I've read the sticky but I'm having a little trouble on how to bypass photobucket and attach a picture directly to a post.

John Stevenson
07-08-2008, 08:05 PM
With TGTools method you need to get a good fit on the threads and register before you cut the thread and taper for the ER.
Another disadvantage is that it will still be soft and can wear or mar in use, admittedly not a lot for home shop.

There has been about 3 attempts in the UK to source some Myford thread to ER 32's but all have failed on repeatability.

With Derekm method [ post # 5 ] you get to machine the register in situ and if anything moves at a later date you have the chance to skim the register and adjust it to run true.
Another advantage is the off the shelf backplate chucks are hardened and ground and they can be swapped over forom machine to machine if needed.

.

tattoomike68
07-08-2008, 08:07 PM
I would ignore the threads and make a sleave that goes into the #4 taper and mates with a 5C collet system with a cam lock draw tube.

ER collets might be fine for turning but I found they are junk on a milling machine and holding an endmill. it seems you have to hammer it as tight as hell to get it to hold worth a crap.

After I had to do some high precision fixture work in some hard ass stainless for our tool and die guy with a mill that had a 40 taper to ER adapter I promised myself I would never use the stupid ER collets ever again. The adapter and the collets should go in the scrap bin and be melted down to be manhole covers. I will never like ER collets, total junk IMHO.

you should be able to fine a 5C collet system that can be mated with your lathe and just has a bushing you pop in the spindle. they are a dandy set up, you would like it better than pounding on a ER collet nut with a hammer.;)

John Stevenson
07-08-2008, 08:17 PM
Mike,
So why don't you use 5C's in the nose of your milling machine then ?

Just up the road from me is an aerospace company running 7 DMG machining centres and two Hass bed mills, 5 axis.
The Hass's are making wing spars for Boeing, 11 hours to do one, 42 tool changes per shift, two spars per day, no operators.

All these tool are in BT40 ER32 holders as are the DMG's. they have a few ER40 for large shanked tooling but most of thier work is standardised on ER32's

We don't see end mill holders over here or R8 on anything bigger than an X3. Single angle collets went out years ago.
The UK and Europe have been on ER's now for about the last 10 years.

Sorry we got it wrong.

.

tattoomike68
07-08-2008, 08:23 PM
Mike,
So why don't you use 5C's in the nose of your milling machine then ?

Just up the road from me is an aerospace company running 7 DMG machining centres and two Hass bed mills, 5 axis.
The Hass's are making wing spars for Boeing, 11 hours to do one, 42 tool changes per shift, two spars per day, no operators.

All these tool are in BT40 ER32 holders as are the DMG's. they have a few ER40 for large shanked tooling but most of thier work is standardised on ER32's

We don't see end mill holders over here or R8 on anything bigger than an X3. Single angle collets went out years ago.
The UK and Europe have been on ER's now for about the last 10 years.

Sorry we got it wrong.

.

I dont care if you use ER, keep a hammer handy to beat the damn things tight if you ever have to horse on some hard stuff.

Timo
07-08-2008, 10:48 PM
you should be able to fine a 5C collet system that can be mated with your lathe and just has a bushing you pop in the spindle. they are a dandy set up, you would like it better than pounding on a ER collet nut with a hammer.;)

5C is the way to go. Back in 83í when I got the lathe, ROYAL would custom make a 5C nose piece adapter with a tube type draw bar and a hand wheel tightenír for a MT4 spindle taper. The cost was about half of what I paided for the lathe so I had to pass on that. Awhile ago I checked with ROYAL again and they told me that they no longer offered this service. I think that the 5C is the best way to go but nobody seems to offer the tube type draw bar and a 5C nose adapter to fit different size spindle nose tapers. If you know where this is available (at a not to outrageous price please) let me know.

derekm
07-09-2008, 06:02 AM
...
ER collets might be fine for turning but I found they are junk on a milling machine and holding an endmill. it seems you have to hammer it as tight as hell to get it to hold worth a crap...

..., you would like it better than pounding on a ER collet nut with a hammer.;)

you were clicking the collet into the nut before inserting into the chuck? This is a common mistake for those used to other collet systems.

Alternatively you can use the ball bearing style clamping nut this gives greater holding power for tougher milling applications.

fwIw my er40 on polished stainless will stall the lathe rather than slip and that just using simple pressure on the collet wrench with a standard nut

Peter N
07-09-2008, 07:01 AM
Mike, you have to remember to fit them small side UP.....:D

Double angle collets like the ER should be far superior to 5C on a like for like size basis for gripping power, as they close and grip uniformly along the length instead of just around the nose taper.
Gripping power is better close to the nominal size and over around half the closing range than right down at the bottom end of the 0.040" range.

I think you must be either using the wrong size, using it right at the bottom end of the range, or not fitting the collet into the nut BEFORE you insert the cutting tool (or stock).

Peter

John Stevenson
07-09-2008, 07:03 AM
If the ER system was rubbish it would have died years ago. Funny that over 1/2 the world is using it and no flags have gone up except for the odd indivual.

Having said that there is no magic collet system that will cover all bases, most have their place either by better features or legacy rights.

The US love the 5C, it's their most popular collet system for work holding just as the R8 is a popular one for tool holding. We are inbetween having as usual to adopt most systems but as time goes on the more popular filters to the top hence our use of the ER series which is one of the only ? / few systems that are work and tool holding.

If you have a cupboard full of 5C's though it's a moot point as no incentive will force you to swap a whole system over at home shop level.
Anyone who is setting up though can make a choice to suit.

Derek's post with both ER's at both ends of this lathe and I presume also on his mill makes the most use of a single system.

Do a search on ebay.com.au for 5C collets, they don't exist in any quantity in Australia for some reason so it then becomes expensive for an Ozzie to adopt this system.

As I said earlier no one system will do all, an ER can't use internally expanding because of the front nut closing.
It can't lever close, not because it can't just that no one yet has built a lever closing chuck for ER's
Crawford's do a lever closer for their collets which are not dissimilar, so the system can be used if someone recognises a need.

.

SDL
07-09-2008, 07:06 AM
I would ignore the threads and make a sleave that goes into the #4 taper and mates with a 5C collet system with a cam lock draw tube.

ER collets might be fine for turning but I found they are junk on a milling machine and holding an endmill. it seems you have to hammer it as tight as hell to get it to hold worth a crap.

After I had to do some high precision fixture work in some hard ass stainless for our tool and die guy with a mill that had a 40 taper to ER adapter I promised myself I would never use the stupid ER collets ever again. The adapter and the collets should go in the scrap bin and be melted down to be manhole covers. I will never like ER collets, total junk IMHO.


You obviously forgot to tell Has as well as they had quite a few CNCs all set up with ER collets machining all day at

you should be able to fine a 5C collet system that can be mated with your lathe and just has a bushing you pop in the spindle. they are a dandy set up, you would like it better than pounding on a ER collet nut with a hammer.;)

You obviously forgot to tell Hass as well as they had quite a few CNCs all set up with ER collets machining all day at the national machine tool exhibition at The NEC in Birmingham (UK) the other month.

We also have a subcontactor who does all our 316 stst machining incuding thread milling all or ER except the face mills.

Steve Larner

derekm
07-09-2008, 08:17 AM
...
Derek's post with both ER's at both ends of this lathe and I presume also on his mill makes the most use of a single system.

...

.

Thats right the MT3 fits both the tailstock and the vertical head on the Omnimill. Just got to get the int 40 chuck for the dividing head.

As regards the lathe the adapter plate settled a bit (A feature of the odd bayonet system on the lathe) and so I trimmed it a thou or so just as you said.