Mosey
Well-Known Member
Decided to get some ER 32 collets for my 10K lathe, which has an MT3 spindle. What kind of drawbar should I use? Some ER's are available with 1/2" thread on an MT# shank. Is that the best I can do?
ER collets in South Bend lathe
- Thread starter Mosey
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Mosey,
If it were me? I actualy wouldn't go with that type of chuck. It's then only good for short pieces. Personaly I think a piece of steel screwed, or camlocked to fit your lathe's spindle nose is a better system. And then just cut the ER internal taper and the threads for the ER nut. That's probably a much more usable setup.
And to even get good accuracy with a MT type collet chuck, You'd need to spotlessly clean your lathes internal taper every single time before using that type of chuck also.
Pete
If it were me? I actualy wouldn't go with that type of chuck. It's then only good for short pieces. Personaly I think a piece of steel screwed, or camlocked to fit your lathe's spindle nose is a better system. And then just cut the ER internal taper and the threads for the ER nut. That's probably a much more usable setup.
And to even get good accuracy with a MT type collet chuck, You'd need to spotlessly clean your lathes internal taper every single time before using that type of chuck also.
Pete
techonehundred
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I built my own. Just bought a nut and made the taper to fit. I went with er 40, because I have a 2 1/4" threaded spindle. here is the
thread.
http://www.homemodelenginemachinist.com/index.php?topic=17925.msg184976#msg184976
thread.
http://www.homemodelenginemachinist.com/index.php?topic=17925.msg184976#msg184976
Mosey
Well-Known Member
Maybe I should say that I have no capacity for metric threading, so I want to buy a holder with a thread that I can make for a drawbar. Hopefully, I can get some through hole into or even though the drawbar. So, if the through hole is no bigger than what I have now (5/8") why don't I just get an ER 25 x MT3 holder, and use the ER 25 collets I already have on the mill? Or, get an ER 32 x MT3 holder, new collets, and take advantage of the extra size for short workpieces that can't go all the way through the holder? Or, is there an ER holder that screws onto the 1-1/2" x 8tpi spindle?
Sorry for being so confusing.
Sorry for being so confusing.
Mosey,
There are a few dealers around for the type Of collet chucks I mentioned. It may require a threaded backplate to fit your lathe. Due to a few newer accesories coming out, I kind of wish I had gone with the ER-32's instead of the ER- 40's I did go with.
Pete
There are a few dealers around for the type Of collet chucks I mentioned. It may require a threaded backplate to fit your lathe. Due to a few newer accesories coming out, I kind of wish I had gone with the ER-32's instead of the ER- 40's I did go with.
Pete
Hi Mosey,
Arc Euro Trade has a backplate mounted type of ER-25 and ER-32 collet chuck. See this page: http://www.arceurotrade.co.uk/Catalogue/Collets/ER-Lathe-Collet-Chucks
They are great to deal with and every order that I have purchased from them arrived very quickly.
This type of collet chuck mounting will allow you the full 5/8" through you spindle and because you mount it just like a plain-back chuck where you must machine the register diameter in-situ on your lathe spindle, you can expect very good accuracy. However, it wouldn't be difficult to incorporate an 'adjust-tru' feature into the backplate if the T.I.R. when mounted isn't up to your expectations.
Regards,
Mike
Arc Euro Trade has a backplate mounted type of ER-25 and ER-32 collet chuck. See this page: http://www.arceurotrade.co.uk/Catalogue/Collets/ER-Lathe-Collet-Chucks
They are great to deal with and every order that I have purchased from them arrived very quickly.
This type of collet chuck mounting will allow you the full 5/8" through you spindle and because you mount it just like a plain-back chuck where you must machine the register diameter in-situ on your lathe spindle, you can expect very good accuracy. However, it wouldn't be difficult to incorporate an 'adjust-tru' feature into the backplate if the T.I.R. when mounted isn't up to your expectations.
Regards,
Mike
Mosey
Well-Known Member
So, what must I do, machine an adaptor plate to fit my spindle, and then bolt the ER plate to it? Then the issue would be that I must get the 2 plates accurately positioned on the spindle, correct?
Mosey,
You should be able to buy prethreaded chuck backplates. Just thread it onto your lathes spindle, Machine the backplate to fit the collet chuck. Then just bolt the two parts togeather. Since I don't own a South Bend lathe, I just can't be more specific on what you'll need. I'd buy the collet chuck first and go from there as far as what size of semi machined backplate you'd need.
Pete
You should be able to buy prethreaded chuck backplates. Just thread it onto your lathes spindle, Machine the backplate to fit the collet chuck. Then just bolt the two parts togeather. Since I don't own a South Bend lathe, I just can't be more specific on what you'll need. I'd buy the collet chuck first and go from there as far as what size of semi machined backplate you'd need.
Pete
Mosey
Well-Known Member
Got it, thanks. I'm off to find a chuck in the USA.
Hi Mosey,
Pete is spot-on. Tools4Cheap has them.
http://www.tools4cheap.net/proddetail.php?prod=er32plate
Regards,
Mike
Pete is spot-on. Tools4Cheap has them.
http://www.tools4cheap.net/proddetail.php?prod=er32plate
Regards,
Mike
Mosey,
This is how I made the drawbar for when I converted my lathe to a Myford nose instead of the D1-4, which allowed me to make and use Myford chucks and fittings on both lathe and mill.
http://madmodder.net/index.php?topic=1993.msg20641#msg20641
And if you do find a way to cut metric threads, this is how to make an ER 32 collet holder.
http://madmodder.net/index.php?topic=2249.msg23587#msg23587
John
This is how I made the drawbar for when I converted my lathe to a Myford nose instead of the D1-4, which allowed me to make and use Myford chucks and fittings on both lathe and mill.
http://madmodder.net/index.php?topic=1993.msg20641#msg20641
And if you do find a way to cut metric threads, this is how to make an ER 32 collet holder.
http://madmodder.net/index.php?topic=2249.msg23587#msg23587
John
Mosey
Well-Known Member
I'm speechless at this incredible work! I'll go back to my humble beginner stuff sand keep chugging away. I hope to make a backplate, and to fit the new collet chuck to it, and get them all clocked in to something like accuracy.
Thanks for the ride.
Mosey
Thanks for the ride.
Mosey
If you have a threaded spindle nose, you can get an ER32 chuck that threads on to the spindle, such as this:
http://www.bealltool.com/products/turning/colletchuck.php
http://www.bealltool.com/products/turning/colletchuck.php
Mosey
Well-Known Member
Wonderful source for collet chuck. It's ordered and saved me all of the work making backing plates, etc.
Mosey
Well-Known Member
Yes, and they will be on the brown truck Monday. I will let you know how they perform.
The collet set is waiting patiently on my bench. They will also be evaluated.
I bet I'm more impatient than you!
The collet set is waiting patiently on my bench. They will also be evaluated.
I bet I'm more impatient than you!
Mosey
Well-Known Member
Boo Hoo.
Brown truck arrived with the collet chuck. Chucked it up after carefull cleaning of spindle threads. Spindle TIR .0002 max. Chuck exterior TIR .007". Cone inside where collet seats .006". 1/2" ground test bar at nose of collet .006" Chuck person says the will either find one with better runout (.oo3"?) or refund $.
We'll see.
Brown truck arrived with the collet chuck. Chucked it up after carefull cleaning of spindle threads. Spindle TIR .0002 max. Chuck exterior TIR .007". Cone inside where collet seats .006". 1/2" ground test bar at nose of collet .006" Chuck person says the will either find one with better runout (.oo3"?) or refund $.
We'll see.
Mosey,
For a collet chuck, 0.003" is way too much runout, it has to be at most a tenth of that figure otherwise it is not worth fitting, you can get better results using your normal 3 jaw.
There is really only two ways to go about it to achieve the required accuracy, and I have used both methods.
The first is to attack a commercial one like you have already bought with an internal toolpost grinder, and true up the taper whilst it is fitted to your spindle. I have done this with four of my own 5C collet chucks and two ER collet chucks for friends who own Myford lathes that had the same problem as yourself with commercial units (I can convert my lathe to a perfect running Myford nose rather than the D1-4 that it normally is).
I would not recommend trying to true up the taper with tungsten tooling because so little has to be removed, you could almost guarantee that the taper would get buggered up trying to do it, grinding is really the only way.
The second method is what I have already shown you, make your own.
You say that you can't do metric threads on your machine, but I will bet you that you can. With combinations of change wheels, you will be able to cut metric threads close and good enough to use for this job. I used to do it all the time on my old all imperial Atlas 10F, it's operating manual came with all the threading charts in there for doing pseudo metric. You just need to be able to screwcut by the permanently closed half nuts method.
John
PS, have a look at my signature line, I swear by it.
For a collet chuck, 0.003" is way too much runout, it has to be at most a tenth of that figure otherwise it is not worth fitting, you can get better results using your normal 3 jaw.
There is really only two ways to go about it to achieve the required accuracy, and I have used both methods.
The first is to attack a commercial one like you have already bought with an internal toolpost grinder, and true up the taper whilst it is fitted to your spindle. I have done this with four of my own 5C collet chucks and two ER collet chucks for friends who own Myford lathes that had the same problem as yourself with commercial units (I can convert my lathe to a perfect running Myford nose rather than the D1-4 that it normally is).
I would not recommend trying to true up the taper with tungsten tooling because so little has to be removed, you could almost guarantee that the taper would get buggered up trying to do it, grinding is really the only way.
The second method is what I have already shown you, make your own.
You say that you can't do metric threads on your machine, but I will bet you that you can. With combinations of change wheels, you will be able to cut metric threads close and good enough to use for this job. I used to do it all the time on my old all imperial Atlas 10F, it's operating manual came with all the threading charts in there for doing pseudo metric. You just need to be able to screwcut by the permanently closed half nuts method.
John
PS, have a look at my signature line, I swear by it.
