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View Full Version : chuck collet closer cheap solution?



Alistair Hosie
10-20-2003, 09:01 PM
Is it feasable to hold collets in a standard chuck.I know it is not feasable "as is" but why couldn't a set of jaws be made that would hold collets. This way a standard three jaw chuck could be utilized for this job.I have wondered this for a while I am sure somone will have done it but I see no reason why this would not be an economical solution to holding collets in the lathe.After all the chuck needed for holding collets are all very expensive I feel this could /should be done if not already.Alistair

Forrest Addy
10-20-2003, 09:55 PM
Collet jaws for a three jaw? Why not? I assume you have a three jaw with two piece jaws. You could bore a set of soft jaws into collet jaws and mark them for repeatable replacement. You'd need to bore the back taper and the front accurately but that's basic.

The tricky part is how you grip the collet's reference diameter adjacent to the draw bar threads. The collet won't have a great deal of rigidity without this extra bore. Side force would tend to upset it in its very short taper. Maybe it could inserted in a plug tightly fitted to the three jaw bore.

[This message has been edited by Forrest Addy (edited 10-20-2003).]

uute
10-20-2003, 10:43 PM
Hi Alistair,

That's an interesting idea.

Sounds like it might be possible, but I don't think such a set up would be very rigid. The jaws would need to taper slightly for clearance on collet tail (reverse bellmouth). This clearance would likely change with each setup - not enough taper = loose grip; too much = floppy rear = poor alianment to axis.

Also, wouldn't you loose the tight concentricity that is a major advantage of collet closer in the first place?

Then again, try it and see. All above is guess work. Isn't it written somewhere: "One experment is worth 1000 expert opinions."

And my opinion is farrrrr from expert. : )

uute

Oso
10-20-2003, 11:11 PM
Dang it Alistair....

Don't you got a lathe over there?

That's all you need to make a great closer for your machine, custom fit and closer tolerance than a store-bought'n one (well, OK, you need material).

What size do you want to use? 5C? Complete dimensions for 5C and 3C are available on-line and you can size a closer from them.

It's not hard to do, actually, and its good practise. If you can make all that wood stuff in the pics, for sure you can handle it. Should take a couple evenings pleasant work.

wierdscience
10-20-2003, 11:16 PM
Well if you bore soft jaws like Forrest I don't see why not,so long as you number stamp and put them in the same way each time you shouldn't have any problems and the concentricity would be just as good.

If you wanted to make it really cute you could bore them with a lip in front to catch the face of the collet so when you chuck down on it the collet would close without the need for a drawbar.

uute
10-21-2003, 12:18 AM
OSO's got it! A 5C collet closer was Job 1 on my lathe. May have taken me more than couple evenings, mind you, but it sure drove home a few axioms (like it ain't flat, square true, or concentric 'till YOU make it that way!!).

Great project -- somethin' I use all the time!

Ryan

Boast WARNING: BTW I just got publised on MetalWebNews! (Am I da expert now?? -- as in Former Squirt me hinks).

uute
Ryan Flaherty
(Making a Fixture for the Above Tool Holder)


I think I see a shrink afor my head explodes!

Alistair Hosie
10-21-2003, 09:54 AM
The lathe I have is a D1-4" camlock fitting so no nose spindle thread so a screw on collet closer is not an option.I would need to buy a collet chuck or a drawbar assembly but just wondered if a standard chuck could be used to hold collets Alistair

JCHannum
10-21-2003, 10:32 AM
I am sure it can be done, but:
Two of the main reasons for use of collet chucks are the accuracy of the set up, and the ability to handle small parts close to the spindle.
Both of these advantages are lost by use of a three jaw chuck to hold the collet.
The D1-4 spindle usually has an MT #5 spindle which will accept a 5C collet closer. Making a 5-C closer and draw bar is a simple job. It would probably be easier to do this than cobble up something using a three jaw chuck.

Rustybolt
10-21-2003, 10:43 AM
<font face="Verdana, Arial" size="2">Originally posted by Alistair Hosie:
The lathe I have is a D1-4" camlock fitting so no nose spindle thread so a screw on collet closer is not an option.I would need to buy a collet chuck or a drawbar assembly but just wondered if a standard chuck could be used to hold collets Alistair</font>

I've done it with 5C collets in a 3 jaw chuck. The purpose was not to mar the finish on a ground part. The accuracy is the same as the the 3 jaw plus whatever error there is in the collet.As far as I could tell it had no adverse effect on the collet. I later bought the Bison 5C collet chuck(the one that uses a wrench{spanner} instead of a drawbar

Oso
10-21-2003, 01:16 PM
Well, you make the "chuck" (closer) AND the drawbar, otherwise buy the lot.

Dunno about nose-only (no drawbar) ones fitting D1-4, maybe Sjogren?


Cost to make the adapter, maybe $15 if you have to buy some of the material, and a couple evenings time.
Not exactly prohibitive.
OK, OK, I'll quit suggesting to use the lathe to make something http://bbs.homeshopmachinist.net//tongue.gif

[This message has been edited by Oso (edited 10-21-2003).]

JCHannum
10-21-2003, 04:27 PM
I have had Sjogren 5C and Jacobs rubberflex collet chucks in D1-4 direct mount. The Bison 5C collet chuck is also available in D1-4 direct mount.
$200-$500 price range on eBay.

Alistair Hosie
10-21-2003, 04:29 PM
What I am suggesting is not to hold a collet in a standard three jaw chuck but to mill say a set of overjaws to fit into it which would be accurate enough to take the collets without punishing them. I E not just rounding off the present jaws although possibly this would work, but to make an overlay set of jaws, or complete new jaws which are designed to take collets. This could be done commercially as I see it would be cheaper than a complete designed collet chuck which at present is prohibitively expensive. Alistair

Joel
10-21-2003, 05:11 PM
Perhaps I am missing something, but why not just use a collet block. Hexagonal for the 3 jaw, square for the 4 jaw (could indicate it in tighter). They cost almost nothing, and are handy to have for quick indexing on the mill. Anything but a decent collet chuck is probably going to reduce accuracy enough, to bring into question why you need to use a collet in the first place, (slight marring of the work piece aside).

Alistair Hosie
10-21-2003, 07:17 PM
seen this on ebay its like somebodys done it already but oooh the price .We should be able to do this or similar ourselves with a standard chuck and a modification.Or what do you guys think will this be easyish to duplicate ourselves Alistair

5C Collet Lathe Chuck Jaws ALL Sizes $600 NEW Item number: 2565507826

JCHannum
10-21-2003, 08:24 PM
$600+ and chuck is still in the way. Still needs drawbar to tighten collet.
Does not compare favorably to $1.380 I spent for material for my adaptor and drawbar.

Alistair Hosie
10-21-2003, 08:36 PM
J C I think the last post is a good idea if you can get a Bison collet chuck for $200 but they don't come up here in UK at that price and importing from USA is prohibitive.You guys have all the fun still will keep my eyes open as I am in no rush Alistair

uute
10-21-2003, 10:04 PM
uh oh eeh eeh! Made a Monkey outa me! Again! Looks like the main selling point of the system on ebay is not having to remove a large & heavy chuck.

0.0008 - .0015" - wish my 3 jaw was that tight, let alone w/collet. Lucky the homemade collet closer is pretty good.

Just curious Alistair, are there many of the cheap Chinese items available over there?

uute

Alistair Hosie
10-22-2003, 04:19 AM
UUTE I am afraid so we are inundated with them.Having said that they are not all disasterous and its horses for courses.
I feel since the Chinese have flooded the market with cheap variable options to the customers the other main brand companies have had to drop prices.
When the first hand held portable battery operated drill came out here on the market the cheapest was several hundred ppounds,you can buy a litlle cheapie for a few pounds now.
Okay its not going to last the rest of your days (after all what is?) but it has made the big companies take notice as they began to lose out to these offers.
The actuall quality of the Chinese stuff has also improved and that has made some of their stuff more interesting to buy.
Also there are a lot of lathe/milling stuff chucks, collets, etc in Europe from India at the moment.
This used to be junk, but in the last ten years has become quite good and is a real alternative for the occasional /hobby user Alistair

ulav8r
10-22-2003, 05:00 PM
Both McMaster Carr and MSC have an adapter that holds a 5C collet that can be held in a chuck. MSC's has a nut on the back to tighten the collet, McMasters has the lock and release on the front.

One like MSC's could be made in the home shop easily, only equipment needed would be a lathe, boring bar and standard tooling. Design is just a round block with a flange bored to hold the collet. A holder similar to McMasters would be slightly more difficult, probably thread the collet holder on the OD and let the thread of the collet stick out the back, thread the outer body to take the collet holder and to hold the back end of the collet. Place the main body in the chuck, thread the collet body all the way into the main body and thread the collet in the assembly. Then screw the collet holder out till the collet tightens. The collet holder thread should probably be left hand thread so the collet does not loosen as you try to tighten the collet holder. ( not as clear as a drawing, but I don't have a drawing.

uute
10-23-2003, 01:05 AM
Getting a little off topic, Alistair, but I wondered about the imports after you mentioned the Bison chuck. Personally, I would rather send MY money to India than China, but I see far fewer Indian imports in tools /acces. (I understand the India has a smaller industrial sector, and then they were too cozy w/Soviets for our Gov.)

Anyway, using a collet without having to remove a chuck would be pretty Nice! My favorite trick is to mount work/cutter in collet, tweak in set-up, go to set my speed. That's when I realize I need to change ranges (by by moving the belt -- you know - the one under the metal cover that I can't take off w/drawbar holding collet!). Ee gerr!

uute

Thrud
10-23-2003, 01:45 AM
Alistair

Shipping the Bison 5c or 16C form Canada would not be more than $100 (CDN) by mail. The are shipped in wood boxes.

Alistair Hosie
10-23-2003, 11:38 AM
Dave the last time I bought something from the USA it cost me $240 when it came here I hasd to pay usps £40 for the pleasure of paying the Value added Tax plus the tax itself 17.5 percent plus import duty plus $80 delivery plus a charge from usps for storage which I did not ask for, but they explained to me that the company sending it had not filled in a four digit part of the delivery note and it had to be put into storage till they phoned the company for the info and oh sorry we have a three day minumum storage charge even though it was only in storage half an hour so the product cost me more than twice what it should have. Sorry not again thank you. Yet my friend uses postal service or ups he never gets charged anything as he does it during the week and they only check parcels for tax etc every now and then.I think I will change my name to lucky http://bbs.homeshopmachinist.net//biggrin.gif Alistair