5C collet for lathe

[aribert]

When I bought my Clausing 5914, it had a Royal collet closer attached to it. I had never seen / used collets before and to reduce the buy price the used machinery dealer stripped off the closer (in hindsight one of my worst $100 savings).

I have since used collets a few times in a Hardinge HLV-H - what a dream machine. Now I want to add 5C collet capability to my lathe - I already have a Jacobs rubber flex collet chuck and collets though I tend not to use them that much.

My plan was to make a drawbar style collet closer. How much torque is needed to tighten the closer - will I need to plan on a pin spanner wrench? I acquired a mystery collet closer for a starting point. My concern is machining/grinding the mating tapers. I have no taper attachment so I am presuming to offset the tailstock. If I modify one of my existing parts either machine a 4.5 MT to the OD of the existing collet chuck or machine out the ID of the 4.5MT ODx3MT ID adapter I have to mate with a 5C collet, I need to figure out how to hold these parts and be able to machine either the OD or ID. I have never (intentionally) machined a taper. I have a simple/crude tool post grinder to finish the surfaces (if I can get the taper correct).

The other option is to buy a collet chuck. I read the recent thread http://bbs.homeshopmachinist.net/thr...huck-s-Closers and looked at the link for the Gator brand 5c collet chuck. That is currently more than I am willing to spend for something that is a "want to have". I have seen cheap import 5c collet chucks for under $150. If I were to mount one of the cheap 5c collet chucks on a backplate so that I have radial adjustment (like an adjust-true chuck), is there a hope that I could end up with a reasonably repeatably concentric collet chuck? To me reasonably repeatable would be say 0.0015 or slightly better. Anyone have experience with the cheap China collet chucks? The cheap 5C collet chucks seem to run about $135 or so - here is one with the L-00 backplate that I would need: https://www.ebay.com/itm/BOSTAR-5C-C...ox!60639!US!-1

[aribert]

Images below are: my lathe spindle with 4.5 MT bore, hand wheel where the drawbar end would mate and two views of the parts available to modify to make a drawbar closer.

Sent from my 5049W using Tapatalk

[dalee100]

Hi,

I bought a cheap and cheerful Chinese 5C off of eBay and mounted it to a back plate that I could "tap" in for runout and it works great for me. Once adjusted, I still get just a bit less than .0005" runout on a 1/2" dowel pin. Dismount and remount on my 8x14 is very repeatable so far.

[Mcgyver]

I hope you didn't take the taper attachment off for another $50 yup, worst $100 you ever saved. You've got a MT 4 1/2 spindle? Perfect for a 5C adapter and collets right in the spindle are the best set up. The tapers needed are not long so you could do them with the compound. There was a day I'd have not even thought about outsourcing it, but nowadays its just more on the the todo list so might look at what someone with a cnc would charge to knock one off. Or knock 5 off, sell them on ebay and get yours for free. A HT chrome moly ought to be sufficient, but if you are outsourcing, hardened and ground would be really nice

[Low Flyer]

It would probably be easier to buy one like this one and then lengthen or shorten the tube as needed. This is just a result of a quick Ebay search. I love my Royal collet closer. They are hard to beat.

https://www.ebay.com/itm/ROYAL-15-5C-COLLET-CLOSER-With-5C-SPINDLE-NOSE-ADAPTOR/113830770429?hash=item1a80d7b6fd:g:nmUAAOSw7PFdOaME

[BCRider]

Not sure what you have that can be used. But in my case I made up all the parts shown below and the second pic shows the collet chuck in use.

I needed the nose extension in my case because my lathe has a gap bed. And the filler does not extend all the way to the head stock. So I needed the extension from the head as shown. And the chuck portion actually screws onto the spindle threads and tightens in place with the G wrench shown.

Tightening the chuck itself and the drawbar to hold the work is just a couple of medium palm bumps once snug. No need for any sort of extension pipe. The wrench shown is 11" long overall. Literally 10.5 from "hook to hole". So clearly it doesn't take a gorilla grip to hold stuff in the collets.

The hand wheel on the drawbar is the same OD as the fat end of the chuck itself.

[CCWKen]

I'd get that 5C collet chuck in a heart beat. It comes with a back plate.

The only drawback I see with mine is the long winded screwing to tighten. I cured that with a driver that fit the pinions.

[rickyb]

When I bought my Clausing 5914, it had a Royal collet closer attached to it. I had never seen / used collets before and to reduce the buy price the used machinery dealer stripped off the closer (in hindsight one of my worst $100 savings).

I have since used collets a few times in a Hardinge HLV-H - what a dream machine. Now I want to add 5C collet capability to my lathe - I already have a Jacobs rubber flex collet chuck and collets though I tend not to use them that much.

My plan was to make a drawbar style collet closer. How much torque is needed to tighten the closer - will I need to plan on a pin spanner wrench? I acquired a mystery collet closer for a starting point. My concern is machining/grinding the mating tapers. I have no taper attachment so I am presuming to offset the tailstock. If I modify one of my existing parts either machine a 4.5 MT to the OD of the existing collet chuck or machine out the ID of the 4.5MT ODx3MT ID adapter I have to mate with a 5C collet, I need to figure out how to hold these parts and be able to machine either the OD or ID. I have never (intentionally) machined a taper. I have a simple/crude tool post grinder to finish the surfaces (if I can get the taper correct).

The other option is to buy a collet chuck. I read the recent thread http://bbs.homeshopmachinist.net/thr...huck-s-Closers and looked at the link for the Gator brand 5c collet chuck. That is currently more than I am willing to spend for something that is a "want to have". I have seen cheap import 5c collet chucks for under $150. If I were to mount one of the cheap 5c collet chucks on a backplate so that I have radial adjustment (like an adjust-true chuck), is there a hope that I could end up with a reasonably repeatably concentric collet chuck? To me reasonably repeatable would be say 0.0015 or slightly better. Anyone have experience with the cheap China collet chucks? The cheap 5C collet chucks seem to run about $135 or so - here is one with the L-00 backplate that I would need: https://www.ebay.com/itm/BOSTAR-5C-C...ox!60639!US!-1

I say forget about 5c. You can't buy enough collets to make it complete. Also stand out from the spindle is significant. Go with ER50 or 40 at the minimum. One set of collets covers every diameter out to around 30 mm. No draw bar required and a far better grip than 5c. I made an er40 chuck for my 10" Logan. Collet set covers 3-28mm. Bumped the upper limit many so many times, wish I went to er50.

You would be amazed at how smooth cut offs go usually at ~1/2 the speed used to turn the part. Made an er40 chuck for my 7x14 mini also. Can't do that with 5c. You will have to buy the closer nut. Get the bearing style not the plain nut.

[oxford]

If you do go 5c, you should make a collar that goes over the external spindle taper that engages the threads that hold the chuck on. You then use this to pop the 5c adapter out of the spindle.

There was a manual collet closet on the Clausing 6300 lathe at a place I worked and it had a shop made wheel on the end around 8” in diameter. It seemed to be fine for torque on the collet.

A lever closer is worlds above a manual closer for speed if you have a bunch of parts that you need to run off. You don’t even have to turn the machine off for parts chanes.

[djc]

I think there is a company called JFK Products or JFK Precision who sell 4 1/2 Morse to 5C adaptors.

[Mcgyver]

I say forget about 5c.

It certainly could save some money in collet purchases, but split collets like the 5Cs' have lots of advantages for work holding over ER's (which are great for tool holding)

I already have a Jacobs rubber flex collet chuck and collets though I tend not to use them that much.

I use split collets and rubberflex, don't get rid of it, they each have there subtle advantages. If its the only collet system you have though, why aren't you using it?

[dalee100]

I say forget about 5c. You can't buy enough collets to make it complete. Also stand out from the spindle is significant. Go with ER50 or 40 at the minimum. One set of collets covers every diameter out to around 30 mm. No draw bar required and a far better grip than 5c. I made an er40 chuck for my 10" Logan. Collet set covers 3-28mm. Bumped the upper limit many so many times, wish I went to er50.

You would be amazed at how smooth cut offs go usually at ~1/2 the speed used to turn the part. Made an er40 chuck for my 7x14 mini also. Can't do that with 5c. You will have to buy the closer nut. Get the bearing style not the plain nut.

Hi,

The problem with ER collets is that they only come in rounds. And like taps and dies, you do not need every size possible.

What happens when you need to make some stuff out of hex or square stock? There are no emergency or clutch or pot ER collets made. I've made bunches and bunches of stand-offs and small special fasteners from hex and square stock that need to be worked on from both ends. While still maintaining some semblance of concentricity. Nor can ER's deal with short parts that don't extend far into the collet. Try gripping a 1/32" stub and then machining on it in your ER collet. Isn't going to happen.

ER collets are very limiting for work holding. They work as long as you only do round stock that is long enough to get a good grip on.

[oxford]

To the OP, after looking at your pictures again here is my opinion if you want 5c. Find one of the 4.5mt-5c adapters made for this and save the 4.5mt-3mt, you may want this at some point. You will be ahead of the game vs trying to modify one of what you have.

It looks like you already have the external spindle taper protector which will also push out the 5c adapter i mentioned in a post earlier so you are good there.

The draw bar you have now looks short. I would look for a longer one and cut it to the length you need. Either then put a larger handwheel on the end for tightening or setup for a spanner wrench. Starting with a longer draw bar will again put you ahead instead of trying to lengthening the one you have.

I feel you should also have some sort of thrust bearing between the draw bar and spindle.

[rickyb]

Hi,

The problem with ER collets is that they only come in rounds. And like taps and dies, you do not need every size possible.

What happens when you need to make some stuff out of hex or square stock? There are no emergency or clutch or pot ER collets made. I've made bunches and bunches of stand-offs and small special fasteners from hex and square stock that need to be worked on from both ends. While still maintaining some semblance of concentricity. Nor can ER's deal with short parts that don't extend far into the collet. Try gripping a 1/32" stub and then machining on it in your ER collet. Isn't going to happen.

ER collets are very limiting for work holding. They work as long as you only do round stock that is long enough to get a good grip on.

I appologize for not mentioning the drawbacks. They really are not important to me so of course I fail to mention them. Not very considerate.

For me it is far more important to handle any round diameter, whatever it might be. Using it on two lathes is a big plus. I can chuck them in my rockwell mill also but don't use them there until I need to use a metric tool.

[Paul Alciatore]

I have the smaller 3C collets for my SB-9 and a manual collet closer. The closer has a handwheel with a 3 inch diameter. I had to add some serrations to the handwheel to allow my sometimes greasy hands to fully tighten it. For the 5Cs I would think you would need a 4 or 5 inch handwheel, also serrated or knurled, if you are going to tighten it without a wrench. A wrench would probably be better.

One thing I did was to add a roller style thrust bearing to the closer. That made things a lot easier. I would highly recommend that if you make or use a manual closer.

I have purchased a set of 5Cs for use in my spin index. I plan to make a collet holder for them for my SB from an old three jaw chuck. The chuck will provide the body and the scroll plate so I can tighten them with a key. I will need to machine a new front with the collet taper for it.