Lathe collet chuck

[Bill DawesParticipant @billdawes]

Hi all,

I have Warco 290V lathe for which I need a collet chuck.

The lathe bore has an MT5 taper (despite manual saying MT3)

I have a Clarke MT3 collet chuck and an MT3 to MT5 adaptor, the chuck I bought for my Machine Mart lathe I bought some time ago, now replaced by my Warco.

Problem with the Clarke chuck is it only takes Clarke style collets and these seem to be available only in a small range of metric sizes.

So another option is ER25 and ER32 chucks that I have for my milling machine but these are R8 tapers, I cant find an adaptor for R8 to MT3.

So decided that a new MT3 R25 chuck would sort this out but wondered if this is the right way to go or would the alternative of a flanged collet chuck rather than a taper fit. Anyone any experience of this please?

Bill D.

[Bill DawesParticipant @billdawes]

[JasonBModerator @jasonb]

Better to get a flange mounted ER 32 chuck then you don't need a drawbar and can therefore hold longer items, mounts onto a backplate to suit your 290 which can have several different nose options.

ER40 would make better use of your spindle as would a 5C chuck that does not need two spanners and uses a standard chuck key, that's what I have on my 280

[john halfpennyParticipant @johnhalfpenny52803]

You will be able to sell the Clarke set on ebay, and buy a good ER25/32 set with MT for about the same amount. My mill has R8, and I have an adapter to suit the MT3 ER chuck, IIRC from ARC, though you will lose a little headroom.

[Chris Evans 6Participant @chrisevans6]

Plus one for the 5C, 80%% of my work is done in 5C collets.

[old martParticipant @oldmart]

This lathe uses a camlock spindle and may not have any backplates to attach a flange mount collet chuck. With the MT5 socket, the prospect of 5C worth looking into, or at least er32. I just googled MT5 to er32 and there were multiple hits, so these would be your best bet as you already use er32 on the mill.

Edited By old mart on 01/05/2023 21:04:52

Edited By old mart on 01/05/2023 21:07:48

[EmgeeParticipant @emgee]

Posted by old mart on 01/05/2023 21:03:54:

This lathe uses a camlock spindle and may not have any backplates to attach a flange mount collet chuck.

Camlock backplates are available to fit a flanged ER type chuck to, this could then be left as 1 unit so changing between chucks is very simple.

Emgee

[Tony Pratt 1Participant @tonypratt1]

I have a 290V but the older flange type, I use a ER 40 collet system and recommend it wholeheartedly.

Tony

[JellyParticipant @jelly]

I have a spare 163E Dead-Length Lever Action Collet Chuck on a suitable ISO R702 backplate (my lathe came with two), which I could be convinced to part with.

It's currently set up for bayonet type locking (ISO R702:3), but for the price of three camlock studs would work with camlock (ISO R702:2), no spare collets though.

Edited By Jelly on 01/05/2023 21:21:46

[JasonBModerator @jasonb]

As I said earlier the 290 has been produced with at least three different spindle noses –

flat flange with 3 holes for studs and nuts

Flat flange with holes and "keyhole" plate and nuts

Camlock.

Backplates are available for all three and you could also be able to get a direct camlock mount 5C or put it on a backplate

[Bill DawesParticipant @billdawes]

My Warco has a 3 hole flat flange that fits into the chuck recess.

What are pros and cons of 5C and ER, would prefer to stick with ER as I already have several collets or is 5C better for lathe work.

Bill D.

[Tony Pratt 1Participant @tonypratt1]

If you put '5C collets' in the keyword search box [top left of this page] you will see there are answers to your very question

Tony

[JasonBModerator @jasonb]

5C is designed for work holding, ER is originally for tool holding but gets used for work holding.

5C grips short work, ER won't unless you make a bung for the back end

5C is size specific to the collet give or take a small amount, ER is a lot more flexible in range of each collet. However you can get 5C to ER32 adaptors which would allow use of your existing collets for odd size work.

Hex and square collets available for 5C not for ER

As said 5C uses a standard square ended chuck key rather than two spanners needed on ER

5C will hold larger 1 1/8" or 28mm,ER32 only upto 20mm with standard collets.

If you have the leadscrew covers fitted or rear motor stops the carriage going right upto the headstock then the longer overhang of the 5C could be an advantage.

[Neil LickfoldParticipant @neillickfold44316]

I used last year for the first time, a 5C collet system, that is open and closed with a small key, on the side like a regular chuck key. The repeatability was great , and after using it for a couple of days, for the few off parts we were making, preferred it to the collet closer type. I liked the feel that you get when doing up a collet to hold a part. It had all the other advantages of the 5c system, like being able to use flange dead stop plates etc for holding parts to length on a 2nd op for example. The other was the use of emergency collets or collets that you can make to your specific size shapes etc. Yes it seems a lot of money up front, but long term well worth the money. I am in the process of looking for a 5c adapter chuck for my Myford S7.

It needed a D? plate to be fitted to the lathe and cut to the supplied specs to suite the body of the collet chuck and was then indicated in place with the 4 adjusting screws onto the inner reference edge.

Neil

[Tony Pratt 1Participant @tonypratt1]

Looks like you can get some hexagon and square ER collets in the USA from 'Maritool'.

Tony

[SillyOldDufferModerator @sillyoldduffer]

Posted by Bill Dawes on 02/05/2023 08:26:44:

…

What are pros and cons of 5C and ER, would prefer to stick with ER as I already have several collets or is 5C better for lathe work.

Bill D.

I um'd and ah'd about this about 5 years ago and decided to go with ER throughout. The decision depended on what I do in my workshop, which won't suit everyone by a long shot!

Briefly, I always use collets to hold short round stock, not square, hex, or round in long lengths. For this ER is 'good enough', providing a strong grip over a 1mm diameter range, with a reasonable amount of space behind the collet for longer rod. It's cheap and convenient because the same collets are used on my lathe, mill, and vice (with Stephenson Blocks). There are negatives: ER is a tool-holding collet, so round only, and the gripped part of the rod should be as long as the collet's splines. They can nip and hold shorter lengths but it's a bodge, with some risk of coming loose or damaging the collet.

5C is a work-holding system, where collets can be bought to do shapes other than round. They can also hold long stock, and nip short pieces 5C beats ER if any these are important. There are always negatives: the grip diameter range per collet is less than ER, so more collets are needed. More collets means spending my precious spondulicks and finding space to store them.

5C makes good sense in a busy workshop doing repeat work on hex, round, and square stock. ER makes good sense in a one-part-at-a-time workshop, or where round stock dominates, and especially where the owner is short of space and dosh!

I've not regretted going for ER rather than 5C because – in my circumstances – collets are a secondary work-holding method, and almost exclusively needed for round stock only. Only once have I thought, 'this would be easy with 5C'. In practice there's always an alternative, usually a 4-jaw, the disadvantage of them being set-up time.

Dave

[Howard LewisParticipant @howardlewis46836]

+ for S O D's comments.

[VicParticipant @vic]

Posted by Tony Pratt 1 on 02/05/2023 09:35:42:

Looks like you can get some hexagon and square ER collets in the USA from 'Maritool'.

Tony

Oh yes! Bit speedy though. Come on Ketan, get some made up and on the website! 😆

[DiogenesIIParticipant @diogenesii]

Cutwel –ER tapping collets

[JasonBModerator @jasonb]

They don't hold square stock. Most of the gripping area is round and just the back end square so that there is no risk of a tap slipping when doing rigid tapping in a CNC machine

[Chris Evans 6Participant @chrisevans6]

When I sold my Southbend "Heavy 10" lathe after 45 years use I kept the full set of 5C collets that where supplied with the lathe built in 1942 and "war finish". A 5C collet chuck for my Excel 14"x40" lathe was was bought for not a lot of money and the collets are still in use. I have added a few metric and hexagon collets to suit my work. Don't get hung up about accuracy, all my collets run to around 0.001" total indicator reading even the cheap imported ones.

[RobinParticipant @robin]

I bought a MTB5 to ER40 adapter for my lathe. I start to wonder if accuracy increases with size because it is quite amazingly good, once you get your MT5 taper cleaner sorted out that is. Trouble is the through hole is a bit restricting and the side walls are as hard as the top of Gods' head. I can't open them out but I can live with that, unless anyone has a clever suggestion?

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