Homemade 5C Collet Closer

[SteveM]

Always remember to remove the cheater bar before starting the lathe.

Put a little strip of spring steel on the handle to pop it out when it's not under tension, then it will NEVER be in when you start the lathe.

Like the coil spring I have on my chuck key.

Steve

[DocSarvis]

Hello all, new to the site and new to running a hobby lathe. I realize this is an old post but it is what I plan to do and I have a couple questions. I have a 12x36 1984 Enco import that seems to be in good condition, It came with an 8" four jaw and a 10" face plate. I would like to get a 3 jaw and wanted advice on the size. Any suggestions between a 6" or an 8". Next question pertaining to this post. I have a M4 1/2 spindle that is only 2 inches long when I get the adapter turned OD and insert it to turn the C5 ID do I just tap it in firm, I'm only guessing that it will hold to turn. Next how do I get it out, Tap it out thru the spindle or??? Last is there any other useful "Things"I should turn the M4 1/2 taper on to use down the line. I cant really think of any but when I get the angle "ON" I could turn an extra or two if there was a reason. I don't see doing an R8. Thanks in advance for any suggestions. Great site. I've read a great deal and learned some valuable things already. Thanks

[mechanicalmagic]

I have a 12x36 1984 Enco import that seems to be in good condition, It came with an 8" four jaw and a 10" face plate. I would like to get a 3 jaw and wanted advice on the size. Any suggestions between a 6" or an 8".

Doc,
Personally, I much prefer a 6" chuck. They are lighter, and easy to change. My old back doesn't like heavy stuff.
However, if you are planning to hold larger items, an 8" might be better.

Now for the style of the chuck, get REMOVABLE top jaws. (aka two piece jaws.) If you are buying new, it's only a few $ more, given the same model/brand. If you have removable top jaws, you can make "soft jaws" from soft steel or Aluminum. The soft jaws can be machined to very good accuracy each time the chuck is mounted. In addition, you can machine a shallow step for holding thin parts, either OD or ID. And if you make your "soft jaws" in a pie shape, you can hold VERY thin parts with full support.

Dave J.

[Harold_V]

I would think if you turn the outside first the wall would be to thin and deflect between the MT5 and the C5,

You may be pleasantly surprised at the thin wall that can be successfully machined. They can't be excessively long, but if you use sharp tools, avoiding carbide, which generally requires somewhat higher cutting pressures (not always), you can machine relatively short sections that have no more than .015" wall thickness with excellent results. Light cuts and fine feeds are in order, and the tool must have little nose radius, otherwise you have more problems than you can address.

I have machined items such as I've described, even with thinner walls--in the process of making rubber cutters.

One word of caution. When you machine materials that thin, you can expect some movement. If size is critical, do not machine one feature to size, then approach the other. Machine both features alternately, taking small amounts off each one in stages, that way you eliminate distortion of the final product. These are the little tricks you use to achieve success.

Harold

[J Tiers]

McGyver's technique is what I used..... and the closer has worked very well for me for several years. the whole setup took I think 2 nights to make.

I would definitely not try to compensate for chuck errors...., Doing a taper is not hard enough to make that attractive. May as well make it for the spindle.

Do remember to leave plenty of room under the front flange for a "remover and guard" if you have a threaded spindle.... it is easy to take off too much on the taper and "run out of stock" when it seats too deep.

[DocSarvis]

J Tiers, care to elaborate on the "remover guard". is it just a flange to protect the threads and then tap with a hammer to release the taper? Thanks

[Harold_V]

Now for the style of the chuck, get REMOVABLE top jaws. (aka two piece jaws.) <snip>. If you have removable top jaws, you can make "soft jaws" from soft steel or Aluminum.

Very good advice, Dave. In fact, that's advice worth its weight in gold.

Soft jaws are the silver bullet of holding---yet, sadly, often disregarded by the home shop.

Soft jaws are not strictly a production tool----they lend themselves very well to holding objects that, otherwise, can be difficult, if not impossible, to hold while machining. If a small selection of jaw configurations are created at the outset, there is generally a set that can be altered slightly to fit almost any occasion. Couple that with the use of an adjustable spider and you can alter jaws by removing almost nothing when fitting a part, prolonging the useful life of the jaws considerably.

One more suggestion. If steel is used for jaws instead of aluminum, it's perfectly acceptable to weld new material on well used jaws.

Welding on aluminum jaws isn't as desirable due to the fact that the weld process will eliminate the heat treat (artificial aging) of the aluminum. It can be restored only be solution annealing the jaws, then re-aging. That is generally beyond the ability of the home shop, and may be more involved than desirable.

I have soft jaws made of steel and aluminum. If aluminum is your choice, 7075-T6 has tensile strength that rivals mild steel. 6061-T6 is also acceptable.

Properly fitted, soft jaws hold without distortion or marking. They are an excellent choice when finish machining objects that must have a good appearance.

Harold

[spro]

I have enjoyed reading the various ways you gents have gone about this. More to the last msg; The style chuck, actually supplied with many of these 12 X36 Tai lathes MT 4 1/2 -5 2 1/4 " spindle;
POLAND
PUT m 6 1/4ZD
2856
78
The last numbers probably are serial or something but these chucks were excellent and as recommended, two piece/ reverse jaws.
These folks are what became Bison (to my old knowledge).
I was looking thru my stuff to see how I made my closer and as I recall I had a little finding a pipe of max OD to fit thru the spindle and still able to be internally threaded for the 5C. FWIW I also wanted to be able to use "pot chucks ?" of which I had many. These are expanded collets to which went upto about 6" . After aprox 3" they required a backing plate attached to the spindle in place of the chuck. This all had to be machined or "finish machined" on the spindle or headstock. As it turns the larger dia required more torque and a NOS clutch throwout bearing/ housing was machined to allow higher torque.
Then it was found that of course it could slip at that point so since the back end of the spindle was threaded I made a ring to fit that which was machined to fine "dog clutch" affair which mated to another on the tube or handle. I forget because it got so complicated. Anyway the kicker is because one of these elements had some error and the dang CHUCK was so good , It didn't make much difference.
Sorry for the wind.

[spro]

I had missed the entire last page and my response is out of sequence.

[DocSarvis]

Thanks for all the replies and proven techniques. I will definitely opt for the removable jaws and I think 6" should be the best size. The 8" four jaw seems a tad large for what I do but it will be a good standby for when its needed. My taper is lightly scared from use and I was planning to use an automotive three stone hone to clean it up. Is this an acceptable method. Thanks

[Harold_V]

My taper is lightly scared from use and I was planning to use an automotive three stone hone to clean it up.

It's not a great way to go due to the ability to alter the taper.

If you do choose to apply a spring loaded hone, keep the application brief, just enough to kill any highs. If you attempt to get the surface back to one with no defects, chances are pretty good you'll alter it enough to be troublesome.

Harold