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  • wierdscience
    replied
    5C collets in a homemade adapter would be the best setup. Especially since the collets can also be used in a variety of fixtures for the mill.

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  • nickel-city-fab
    replied
    Originally posted by J Tiers View Post
    Another option, which I am certain you can easily handle, is to MAKE the adapter.

    If it is made on your machine, with the boring of the collet recess done in-place, it will be essentially as accurate as you will ever get. Consistent rotational errors of your lathe will be canceled out as much as they can be. If you mark the position in which it was machined, and always replace it in that position, it will be as good as it gets.

    Then use the best 5C collets you can get. You should be well under a thou error, and may do better than that.
    That's exactly what I did with my ER setup -- bored and threaded directly in place. There is no measurable error, even with El Cheapo collets.

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  • J Tiers
    replied
    Another option, which I am certain you can easily handle, is to MAKE the adapter.

    If it is made on your machine, with the boring of the collet recess done in-place, it will be essentially as accurate as you will ever get. Consistent rotational errors of your lathe will be canceled out as much as they can be. If you mark the position in which it was machined, and always replace it in that position, it will be as good as it gets.

    Then use the best 5C collets you can get. You should be well under a thou error, and may do better than that.

    Leave a comment:


  • tom_d
    replied
    Originally posted by brian Rupnow View Post
    My 12" x 28" lathe has an MT5 taper in the end of the main spindle. There is no measurable run-out. The 3 jaw chuck has about 0.003" total indicated run-out, which seems to be to be about normal for 3 jaw chucks in general. If I considered going to a collet system instead of the 3 jaw chuck, what would I need. I know of about three different collet closing options. One is a drawbar which extends thru the spindle and it tightened at the far end, similar to a milling machine, which pulls a collet into a recessed taper to close the collet. I have also seen a large handwheel that fits at the business end of the spindle, and turning it by hand tightens or releases the collet. A friend of mine has what looks like a chuck on his South Bend lathe, but it isn't a chuck. A collet slides or screws into it and the "chuck key" tightens it to pull a collet into a taper in the front of it and closes the collet. Which of these systems is most common and which is the most economical. The only reason I would consider a collet set up is a higher degree of accuracy in the work I do on my lathe. There appear to be many different sizes or grades of collet as well, ranging from MT2 up to MT 5. Any information would be greatly appreciated.---Brian
    These collet adapters show up on places like Ebay from time to time,, and sometimes for less money than what's listed here. This is the simplest way to hold the 5C collet, and being so simple it's also the most accurate, if the tapers are ground concentric. Hold the collet in place with a home made draw tube and hand wheel and you're good to go. Purchase the individual collets a few at a time, as the budget allows, and it's not too painful to get set up. From my point of view, for any lathe from 13" on down, having a 5C setup is a requirement. Well worth the modest investment.

    https://www.ebay.com/itm/28432104615....c101111.m2109

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  • thin-woodsman
    replied
    Originally posted by brian Rupnow View Post
    I will probably stick with my 3 jaw chuck. Now that I am retired, I can't justify purchasing a collet set up, but I did want to know a bit more about them.
    That is wise. If there is one problem with something like the 5C system, it is that there is always something new to buy

    As Bented pointed out, collets won't add any capability to your workshop: they just make certain jobs simpler to set up, or more repeatable.

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  • Mcgyver
    replied


    I think 5c in the spindle nose (adapter) would be the way to go as 5MT will fit 5c. Tighten with a drawbar. 5c are the most common split collet so good used ones often turn up. Its the most accurate and rigid arrangement and you could largely make it yourself.

    Don't go cheap on the collets. The good ones are within a few tenths and the whole point of collet is getting minimal run-out

    If you are not going with a spindle nose adapter and want to get a chuck, I'd go 2J. Same basic form factor but also fairly common and they hold up to 1 5/16". I've just found so many times I'm thankful to be able to hold stock over 1"
    Last edited by Mcgyver; 06-27-2021, 07:07 AM.

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  • JRouche
    replied
    Originally posted by brian Rupnow View Post
    My 12" x 28" lathe has an MT5 taper in the end of the main spindle. There is no measurable run-out. The 3 jaw chuck has about 0.003" total indicated run-out, which seems to be to be about normal for 3 jaw chucks in general. If I considered going to a collet system instead of the 3 jaw chuck, what would I need. I know of about three different collet closing options. One is a drawbar which extends thru the spindle and it tightened at the far end, similar to a milling machine, which pulls a collet into a recessed taper to close the collet. I have also seen a large handwheel that fits at the business end of the spindle, and turning it by hand tightens or releases the collet. A friend of mine has what looks like a chuck on his South Bend lathe, but it isn't a chuck. A collet slides or screws into it and the "chuck key" tightens it to pull a collet into a taper in the front of it and closes the collet. Which of these systems is most common and which is the most economical. The only reason I would consider a collet set up is a higher degree of accuracy in the work I do on my lathe. There appear to be many different sizes or grades of collet as well, ranging from MT2 up to MT 5. Any information would be greatly appreciated.---Brian
    Kinda weird for me, trying to answer Mr. Rupnow. A fine machinist and engineer.

    I have both the lever style pull for 5c on the sb and 10ee. I also have a wheel deal thats on the end and removes all the crap that the lever has.

    I like the wheel deal, manual vs lever collet closer. For both lathes. JR

    P.S> Opps, I meant to add if you do go with a draw tube type make sure the bearings are good. I had a hard time finding the bearings, But they have to be paired.. If you are making your own home groun like I did??

    If you are not then disregard lol. JR
    Last edited by JRouche; 06-27-2021, 12:23 AM.

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  • MrWhoopee
    replied
    I use my 5c collets more than my 3-jaw and 4-jaw combined, probably because most of what I am working with is under 1". If my lathe had not come with collet capability, it would have been the very first thing on my list. I just modified the bore on a couple of these knobs, holding them on the largest diameter in a collet. It would take a custom split bushing to do it in a 3-jaw.

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  • BCRider
    replied
    Originally posted by brian Rupnow View Post
    Thank you for the information gentlemen. I will probably stick with my 3 jaw chuck. Now that I am retired, I can't justify purchasing a collet set up, but I did want to know a bit more about them.---Brian
    For me it's more about being able to use my other 5C work holders. Using my 5C lathe chuck is far less mission critical and is more of a "nice to have" in a home hobby shop.

    Far more important and useful for me is the 5C collet blocks and with the spindexer. Those items alone justified a set of 5C collets for me. And I'm glad that I picked up these items. Both the collet blocks and spindexer have been VERY handy on the mill.

    And with the more recent addition of the ER32 chuck with 5C shank I'm no longer limited to set sizes either.

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  • Randy
    replied
    Don't give up on the idea yet. Keep it in the back of your mind. Even a reduced set of 5Cs (every 1/16 rather than 1/64) you will find very useful. A handwheel type drawtube using an inexpensive needle thrust bearing is a very suitable HSM project, as is a M5 to 5C adapter, especially if you have a tool post grinder. (I don't recall if you do.) For careful hobby use it doesn't need to be hardened, and even 1018 steel would work well enough. I was lucky enough to score about 10 4C collets (perfect for my little lathe with a M4 spindle taper) in exchange for a bottle of Wild Turkey. Made the rest myself and they've been a pleasure to use for 30 years so far.

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  • nickel-city-fab
    replied
    Brian --
    I have a total of $50 in my ER collet setup for the lathe. That's including the new collets from eBay, and a nut fro Mari tool. I started with a piece of large round bar and made it to fit the spindle on one end, and the ER dimensions on the other. Run-out etc. is undetectable even with my best indicators because the collet tapers were machined in place -- I think it was worth it for the time and aggravation savings since I tend to use a lot of standard stock sizes.

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  • brian Rupnow
    replied
    Thank you for the information gentlemen. I will probably stick with my 3 jaw chuck. Now that I am retired, I can't justify purchasing a collet set up, but I did want to know a bit more about them.---Brian

    Leave a comment:


  • chipmaker4130
    replied
    One thing often overlooked on ER collets is the need to pass stock completely through the grip area of the collet or it won't clamp properly. With the 5C if need arises you can clamp on a very small length.

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  • jimsehr
    replied
    I have been machining for over 60 years and I would not be without collets. 5c collets are probably the most common. I have 5c in sets imperial and metric and square and hex. Also 5c step collets can hold short pieces
    with diameters 4 inches or larger. Also 5c emergency collets can be bored to any special size needed. Also I often use 5c inside collets to hold on the inside of parts , These inside collets are dead length collets and z axis will hold true. Hardinge also makes dead length collets. One other thing about 5c collets is they often can be moved from lathe to another machine like grinder or mill. As there are many kinds of tooling like indexers that use 5c collets.I also have 2j collets in sets and rubberflex collets that go to 1 3/8 dia with a Harding collet chuck. With a lever collet closer it is easy to open and close collets in seconds. Even with the spindle running. To see an inside collet working google Rovi collets. Or check you tube. Jim Sehr

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  • chipmaker4130
    replied
    You could also just get a set-tru 3-jaw. My buck stays spot-on once adjusted for a given size. As for collets, you might not get what you pay for. I paid about $300 for what I thought would be a 'better' quality chinese set, 1/16 - 1 1/8 in 64ths. They were junk. Some were not even through or relief-ground to size, preventing stock from passing through.

    I use a Bison 5C chuck (D1-4) and I like it. Its very well made, but pretty slow compared to a lever. Be aware that some draw tubes for levers can cost you thru-feed capability in the larger sizes.

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