Confused on collets

for some of us, the whole point to using collets on small lathes is to allow for turning smaller things and the ability to keep the run out to low numbers (say less than 0.002 inch). Whether you need this capability depends on what you are trying to make and maybe how many of them. The advice given earlier to use your four jaw and maybe learn how to do one is really good. it always helps to do and figure out what can be done better. I frequently have to do something the wrong way the first time. Collets allow for re-chucking with better repeatability.
Just to scatter your thoughts more, turning between centers and using rests may also be considered.
 
Ok so with a 10" length of stainless steel tube that is 8mm in diameter, what would work to hold it?

Basically a metal drinking straw is being made here.
 
Ok so with a 10" length of stainless steel tube that is 8mm in diameter, what would work to hold it?

Basically a metal drinking straw is being made here.
A machine that will pass 8 MM through the spindle minimum, if in the passage of time you need to turn a 12" long length of 20 MM diameter work it will not fit and everything will have to be done on the chuck side. A machine with an 8 MM through spindle bore will not accept 9 MM stock.
As far as actual collet systems that are usable for your single application one of the determining factors will be how fast you need to make the parts. If hundreds or thousands then screwing around with the nuts on an ER chuck will become laborious after a week or so, 5C would be an excellent alternative. There are also other fast collet systems that are not often employed on hobby priced equipment.


Simple as that.
 
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Jay, let me see if I can make this a bit clearer for you. You have a Weiss WBL250F, with a 1.02" spindle bore. It has a 3-stud spindle mount; this means that any chuck (collet or otherwise) must either have the same 3-bolt arrangement on the back of the chuck or you have to mount the chuck to a back plate that has that 3-bolt pattern.

I do not know if anyone makes a direct-mount ER chuck for your spindle; I'm sure someone knows as this is equivalent to a Seig SC6. You can use either an ER-32 or ER-40 chuck. The ER-40 collets go up to 1", which takes full advantage of the spindle bore you have. To use it, you either have to find a direct mount ER-40 chuck or find a back plate and mount an ER-40 chuck to it. You can also do the same with a 5C collet chuck. As others have said, it makes no sense to mount a MT to ER chuck if you want to pass material through the spindle bore.

You finally mentioned that you need to hold an 8mm tube. A collet is probably the best way to hold such a tube so if you're going to do a lot of work with such material then a collet chuck is appropriate. You can get away with using a jawed chuck (3, 4 or 6 jaw chuck) if you're careful and only need to do light work to the piece.

A lot of new guys with a new lathe think that they need a collet chuck. I don't know, to be a part of the gang maybe? The reality is that the vast majority of work in a hobby shop can be done with your simple jawed chucks. Collets are good for turning finished or threaded or thin-walled parts. They are also good if you turn a lot of nominal sized stock; 5C is good for this. Buy a collet chuck if you need it but be sure you know why you need it.
 
Thanks, that info is great!! It really helps, sorry I am just a rookie and have some really basic questions.

I got the lathe mounted on my bench tonight and can see the slide cover where material can protrude from the gear box side.

One of my 1st projects is going to make a 2pc stainless straw for gifts, maybe 20pcs . Turn some simple grooves in them and heat treat to bring out some colors.

Many thanks for the help and suggestions!!

IMG_3618.JPG
 
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It is possible that a simple Morse taper collet and hollow drawbar will suffice for your project.

I am not suggesting that you not buy a collet Chuck, especially if there is a need for it. I simply wanted to point out that it is usually something most of us can delay buying, at least until we have the tooling we need to run a lathe.
 
The ER collets work good with smaller diameter material that might be difficult to hold in larger chucks. They are also pretty at maintaining concentricity in the +/- .001 range especially if you have a means to adjust for runout, like the "set true" systems. You would need to decide on one system as the collect chuck and collets are different for each and each system has a maximum inner diameter. For my 12x36 lathe I went with ER32 which goes up to about 3/4". My lathe is L00 long taper so I had to make a custom back plate. I left about .005 clearance on the collet chuck registration so that I can knock it into exact alignment with a copper hammer. Its kind of a poor man's "set true" but works good.

My lathe happened to also come with a 5C drawbar setup but I don't have many 5c collets and they are much more expensive, and don't have as good of a gripping range.

ER32_collet_chuck_L00.jpg
 
I use one of these round 5C collet chucks held in a 3-Jaw, it has a hex socket (not shown in this pic) that closes the collet with 1/2 or less of a turn, very fast.

Normally I would not use a collet for making one part like this but it was already set up for an 80 part job when my employer interrupted me to make this insert installation tool, hold things like this in the 3-Jaw.
 
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Things are starting to make sense, doing cleaning and disassembly of all sliding parts now.
Getting to see, touch, move and really get to understand co relations between things now.

Was on my way prospecting today and my partners wife called him back for a plumbing issue. So more time to study the manuals and scrub all the gunk off.

What common fluids you all like to use and where on/with the metal lathe?

Thanks, have a great day.
 
Fyi, Tubalcain has a great vid using Morse taper collets and a drawbar.
 
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