5C Collet Closer Question

[CPeter]

I have a Royal collet closer on my Clausing 5914. I spent some time last night dialing it in and it works good with less than .001 TIR. BUT, there is no pin in the collet adapter in the spindle to keep the collet from turning when adjusting or removing it. Is this normal? The 5C collets have a groove similar to the R8 in my mill. I am thinking of putting a pin in the adapter. Is this a good idea?
Peter

[J Tiers]

There are differing opinions....

Some say it is needed, others say it is "OK", and some say it is bad if it makes the closer spin in the spindle taper. I incline to the latter view, because it is kinda helpful getting the collet started and close down, but not THAT helpful, and a spun closer could be an issue.

[oxford]

I have the same lathe and the same closer. My adapter doesn’t have the pin but it has been on my list of things to do for a while. My adapter has a hole where the pin was but came out at some point in time.

With a lever closer you really do need the pin if you want to use the locking ring effectively. A lever closer also allows you to change parts out without stopping the spindle, the pin and locking ring make sure things don’t move and mess with tension.

[Toolguy]

You really need the pin to keep everything set, like oxford said. I have run a lot lever collet closers over the years and never spun a collet. I do take the pin out of the spindle in R8 applications. You don't need it to be timed to something else, and those can spin and become a headache.

[Doozer]

For R-8, I don't think you need it,
but with a lever type closer, with those index notches
if the collet spins, the toggle tightness changes.
So might be a good idea, at least with a lever type closer.

-Doozer

[JoeLee]

If it's the Royal 5C adapter that came with the machine it should have the pin in it unless someone either removed it or replaced the adapter.

Unless you get one of those 3 forked wrenches to hold the collet it's going to be a challenge to tighten it up and like TG said the pin will help with repeatability.

JL................

[Cuttings]

Some of the R8 spindles have set screws with extended tips. There is really nothing to keep them in place. and sometimes they will back out so they no longer extend into the spindle. My mill actually has 2. one above the other. I had trouble with them backing out until I started cleaning the threads and using blue locktite when setting them up. I haven't had a problem since. As far as I know they are both still in place. The blue locktite will allow you to remove or readjust them if necessary.

[CPeter]

Well, no pin for my adapter. A solid carbide spotting drill won't touch it, it is that hard. Any ideas on how to drill a 1/8" hole in it?
Peter

[Rich Carlstedt]

High Speed and lots of force should allow you to drill it with carbide
Rich

[Doc Nickel]

BUT, there is no pin in the collet adapter in the spindle to keep the collet from turning when adjusting or removing it. I am thinking of putting a pin in the adapter. Is this a good idea?

-Keep in mind that the 5C collet, like most machine tool accessories, was designed for production. The ability to rapidly remove and replace a workpiece with the flip of a lever or turn of a handwheel, rather than cranking a chuck key.

The pin keeps the collet from turning, and either screwing onto or unscrewing from, the drawtube. Doing so will change the amount of force on the part, and given the fact the tube has to draw the collet into the taper, it also changes the gauge length of the part.

For home-shop use, either doing a single part or a small handful of parts, it's no biggie. You can pay attention to the collets and adjust your cut or the tension or whatever, as needed.

For a larger run (50-100+) or true production use, the pin is basically a requirement, in order to keep things from moving about over the course of the run.

So if you have no plans to make several dozen parts or so at a time, don't worry about it.

Doc.

[Paul Alciatore]

You talk about a pin making the closer spin in the spindle taper. Others seem to be talking about it making the collet spin (in the closer perhaps?) I do not understand how a pin that is used to orient the collet would make anything spin. It seems that it would prevent things from spinning.

Can someone explain?

There are differing opinions....

Some say it is needed, others say it is "OK", and some say it is bad if it makes the closer spin in the spindle taper. I incline to the latter view, because it is kinda helpful getting the collet started and close down, but not THAT helpful, and a spun closer could be an issue.

[J Tiers]

You talk about a pin making the closer spin in the spindle taper. Others seem to be talking about it making the collet spin (in the closer perhaps?) I do not understand how a pin that is used to orient the collet would make anything spin. It seems that it would prevent things from spinning.

Can someone explain?

The pin fixes the collet in the closer, against spinning relative to the closer. The closer is a friction fit in the spindle. Should be tight, and is a larger diameter than the collet and for sure the work, so not that likely to spin. But the largest work size in a collet might hold well enough to do it in a crash situation, even though the same tension is theoretically holding all the tapers and grips..

Without a pin, the collet is just a friction fit in the closer.

Friction fits can spin. I have seen MT3 spin in a taper. They were probably not cinched down well enough, but.............

So, if the collet is solidly linked to the closer, if anything but the work spins, I guess the thinking is that it will be the closer, which is often not a LOT larger than the collet. A spin would damage the spindle, which is not as replaceable or fixable as the closer.

If anything spins when held in the spindle, I prefer it be the work in the collet, or the collet in the closer, with the closer held securely in the spindle.

Is a problem likely? Eh, probably not. But less likely if the pin is not there, since the collet taper holds less well than any of the others, and will slip before anything else other than maybe the work in the collet.

The pin in a regular collet setup is really to help get the collet closed down on the work as you turn the drawtube with the handwheel so the drawtube threads tighten since the collet is held from turning. But I have never had a pin in my collet closer (I made it, and did not put in a pin), and have had no trouble closing collets securely. I never thought about any issues with a pin, it was a nuisance to put in and I thought I'd see if I needed it before I went to the trouble..

[oxford]

^^^^^^ It took me a couple times reading so to clear up any confusion, what J tiers is referencing as the “closer” is the spindle adapter where the 5c collet sits. I was thinking “closer” as the lever(or hand wheel) and possibly the draw tube.

[oxford]

OP, Doc nickel mentioned it but the pin is definitely not needed for a homeshop or even small run machine.

I mentioned earlier that adding a pin is on my list of things to do but this has been on the list for 10 years now and I have been using the 5c setup in the mean time.

[Doozer]

Why don't you just try using the collet without the pin ? ? ? ? ? ? ? ? ? ?
Instead of asking the half whit gallery to opine the notion to death ? ? ?

-D