Lathe Chuck Questions

[Tecnico]

I'm starting to think about chucks for my recently acquired Standard Modern 1120 and a few questions have come out of that.

First, for those of you out there with the same machine or similar in size, what size of 3 & 4 jaw chucks would have come with that machine or would be appropriately sized?

Second, I'm seeing 3 jaw chucks with two sets of jaws and others with two piece jaws with reversible, bolt on gripping extensions. What are the merits of the two options? I can imagine that the two piece versions would be good for making custom or soft bolt-on pieces but are there any fundamental reasons that one version is better than the other?

Last, one of the chucks I have is marked "Victor Holmes Sons" does anyone know anything about that make? I've searched and found exactly nothing!

Tks.,

D

 

[whydontu]

I miss my old lathe chuck with two piece jaws. It might have been a tiny bit less accurate than fixed jaws, but the ability to mix-n-match jaw types and positions made doing oddball fixturing much easier. Plus the ability to quickly make up custom jaws was great. For example, I needed to machine some thin wall tubing that was too big to fit in my 5C collet chuck. Took three chunks of aluminum, machined to 120* arc soft jaws, put into the chuck, and bored to match the tubing O.D. Perfect fit when clamped with zero distortion.

 

[Tecnico]

Coming back to this, thanks @whydontu for your thoughts on the two piece jaws. The flexibility of being able to make tailored jaws or replacing worn jaws is appealing.

Now to the other detail. For a lathe with a swing of 11” like the SM1120’ would they have come with a 6” 3 jaw chuck? 4 jaw?

I would have thought that the manual would have these details and setup/adjustment info but no such luck. Maybe I’v been spoiled by my Myford documentation.

D

 

[YotaBota]

I can't recall, do you have the 2000 series or the 1120/1334 machine? AFAIK chucks, rests and such were an accessory for the SM lathes, it was sold pretty much bare.

Mine came well appointed with 6" 3 jaw (two piece jaws), 8" dog plate, 8" 4 jaw and a 10" faceplate.

Agree with everything @whydontu says on the 2 piece jaws, drill driver makes the swap from inside to outside easy and fast.

Can't help with the "Victor Holmes Sons" chuck, not one I'm familiar with, yet.

 

[Chipper5783]

That is an easy question to answer - “it depends”. For the 1120 SM, as others have said, 6”-3J, 8”-4J. I have other machines and various chuck options - some chucks have the two piece jaws (top jaw can be reversed, I made two sets of soft top jaws they are also available to purchase from most any machine tooling vendor). Several of my chucks are set up with one piece jaws (two sets with the opposite stair step arrangement). l find the one piece jaws are narrower - sometimes that is just the ticket. I don’t think there is a “best” answer to your question - it depends.

When I bought my 6J, I got it with the two sets of one piece jaws, since I don’t see ever putting soft jaws on the 6J chuck and wanted the smaller close down. When I bought a new 10”- 4J for the 15” lathe (the old 4J is a cheapo, I wanted some new bling) I got it with 2 piece jaws because the other 4J chucks all have one piece jaws (most 4J chucks I have seen have one piece jaws that can be installed either way) - the new chuck is great but delivery on it was really long.

Of course you can go with other size chucks. I have an 8” and a 14” 4J that I can put on the 15” lathe, and either a 6” or 8” 3J for that same machine - I’ve had the lathe a long time, so it is well dressed.

If that is your only lathe, your only 3J, and you are doing typical this and that sort of work, I’d agree that the 2 piece jaws are the way to go (and sizes per comments by others).

 

[Tecnico]

Thanks gents, appreciate the replies.

@YotaBota , my machine is a Series 2000, 1120. By the time it got to me it came with a rather abused 6" 3 jaw "Victor Holmes Sons - made in England" and a better looking but unidentified 8" 3 jaw without a mounting plate plus a dog plate so a bit of a mishmash. Probably Victor Holmes Sons are long gone by now.

I was guessing that 6" 3 jaw and 8" 4 jaw was likely the original config. so it's good to have confirmation on a baseline.

@Chipper5783 Thanks for the insight on the width of the two piece jaws and thoughts on different chuck sizes etc.

I do have another lathe, the Myford and it has standard one piece jaws on the 3 & 4 jaw chucks but it's in a bit of a different class/size.

I think I'm going to walk/crawl/run, maybe a mix of use some of what I have for now and some shopping. I do have a nice 6" Pratt Burnerd 4 jaw that came with my mill and is currently on my dividing head so it might be pressed into use on the SM. I'm going to have to think a bit about the 3 jaw choices for getting up and running & beyond.

Appreciate the info!

D

 

[Susquatch]

I think I'm going to walk/crawl/run, maybe a mix of use some of what I have for now and some shopping.

If it were mine, that's what I'd do too. In fact, I'd prolly just buy whatever made the most sense for my needs and to hell with what it originally came with.

My personal vote would be to get a nice 5C collet chuck first. My collet chuck sees more use than all my other chucks combined times two! I'd put it right up there with the 10 best accessories I ever bought or made.

 

[Tecnico]

If it were mine, that's what I'd do too. In fact, I'd prolly just buy whatever made the most sense for my needs and to hell with what it originally came with.

My personal vote would be to get a nice 5C collet chuck first. My collet chuck sees more use than all my other chucks combined times two! I'd put it right up there with the 10 best accessories I ever bought or made.

Interesting. I’ve maybe used a 5C once. My Myford has a nice set of collets that go up to 1/2” so that’s where my experience comes from. I was putting 5C in the fast running group! The machine does have a nice rack for a load of collets…….

The question of what it came with was to get an idea of “normal” to be able to understand if I was going off pursuing an untamed ornithod without cause. E.g., having the jaws of a too large chuck sticking out too close to stationary objects or getting too small a chuck and regretting it.

I also see ER style collet chucks, what are the relative merits of that option vs 5C?

D

 

[Susquatch]

I also see ER style collet chucks, what are the relative merits of that option vs 5C?

Both are fine systems with a few differences. I have both for the mill and the lathe as well as a 5C indexer.

Fundamentally, 5C was designed for work holding and ER for tool holding. So 5C is more of a lathe tool and ER more a mill tool. But both will do both quite well.

5C has a big through bore which lends itself to holding long stock. Normally, ER deadends in the collet holder but its possible to get open collet holders.

ER requires a nut and wrench. 5C has a rear thread that is either screwed tight or pulled tight.

5C is significantly faster to use.

Any given ER collet has a slightly wider holding range than 5C.

As I said, I have both. I prefer 5C on the lathe and ER on the mill which aligns with their work holding vs tool holding intent.

Either one is better than neither one

 

[terry_g]

5C collets are also made that can hold square or hex stock. I bought my first lathe in 1995 a South-Bend 10K. It came with a chuck that was missing one set of jaws. Finding another set for that chuck was not an option. I wrestled for a while with what configuration to get and finally I bought a 6" Bison made in Poland chuck for it that came with the two sets of jaws. 30 years later I still have that Bison chuck mounted on a different lathe.
I recently bought a 5C collet chuck and find that I use it most of the time.

 

[Chipper5783]

What do you need a collet chuck for? There are a lot of collet systems that work well as a lathe work holding device - pretty well every system has its’ +/-. Get one that fits an actual use that you have. Don’t buy anything, until the application comes along, then buy what works for that task. Of course if one falls in your lap for cheap - take it no matter what it is.

For example, if you have a mill set up for ER32 collets, you’d set your lathe up to accept ER32 collets. However ER32 only goes up to 13/16”. Maybe you have set your mill up with ER25 collets? ER25 would be pretty small as a collet chuck for lathe work. For a lathe using ER collets, I would rather have ER40, which goes up to 1”. The 5C is good, with lots of collets available (various sizes, different styles) but the clamping range is quite small (so you can end up having to get quite a few collets). For 5C you can get various chucks, indexers, and holder blocks - plenty of handy features. The Pratt Burnerd multi size collets are good (a size “C” would fit your machine), giving full coverage from 3/8” to 1.5” (I think it is 11 collets). Jacob’s makes a rubber flex collet similar to the PB (I have not used it). No doubt there are other collet systems you could use, those above are a few of the more common examples.

If you have some fun money for tools and need it gone we are glad to help you with that. The 5C is a pretty good system and useful for lathe, mill table and bench work. It doesn’t have a real strong bite, so work within it’s limitations.

 

[Susquatch]

The 5C is good, with lots of collets available (various sizes, different styles) but the clamping range is quite small (so you can end up having to get quite a few collets).

I use cylindrical shims cut out of pop cans to make larger 5C collets fit smaller stock. Works great. That way I can live with a much smaller set. Plus 5C goes to 1-1/8. Love them.

 

[jcdammeyer]

I use cylindrical shims cut out of pop cans to make larger 5C collets fit smaller stock. Works great. That way I can live with a much smaller set. Plus 5C goes to 1-1/8. Love them.

I have 5C collets that came with the lathe. I use them all the time. I splurged a while ago and also bought a set of square and hex 5C collets. I've only used one of the hex so far but I really like them.
I wanted to build a 5C collet holder on my Harmonic Drive but the inside hole is too small so instead I went with an ER32 collet holder and set of collets. One day I really will cast the back plate etc. Really I will.

 

[YotaBota]

The ER-40 chuck is on my lathe the most and like @Susquatch I use pop can shims for in between sized rod. The collet set from Precision Mathews are not dead ended so you can put thru a long piece.
I have a Hardinge 5C speed chuck as well and have only used it for hex stock.

 

[Johnwa]

A “friend“ told me that it is hard to mount a 6” 4 jaw on a D1-4 backplate as the various holes end up interfering. The D1-4 has three holes for the studs plus 3 holes for the locking screws. A 4 jaw will normally have 4 mounting screws and on a 6” chuck they are on a similar circle as the D1-4 mounting studs.

 

[Chipper5783]

A “friend“ told me that it is hard to mount a 6” 4 jaw on a D1-4 backplate as the various holes end up interfering. The D1-4 has three holes for the studs plus 3 holes for the locking screws. A 4 jaw will normally have 4 mounting screws and on a 6” chuck they are on a similar circle as the D1-4 mounting studs.

That would be a cute little set up. I’m sure one could figure something out (I.e. use a thicker back plate). You can get that in a direct mount 6” D1-4 (PBA). Another option for a small 4J on a D1-4 mount is the half thickness 8” PB (it is less than half the weight of the 8” 4J plane back that I use on my Standard Modern 1120, which is a D1-3). The point being that if you are looking for a pretty small/delicate 4J independent chuck for a D1-4 spindle mount there are a few options (can always go with grabbing the small chuck in a larger one).

 

[Susquatch]

A “friend“ told me that it is hard to mount a 6” 4 jaw on a D1-4 backplate as the various holes end up interfering. The D1-4 has three holes for the studs plus 3 holes for the locking screws. A 4 jaw will normally have 4 mounting screws and on a 6” chuck they are on a similar circle as the D1-4 mounting studs.

I have a D1-5 which has 6 studs. A bigger diameter but in other ways even harder to do. I think I have mounted or built 6 chucks now.

It is ALWAYS a problem. But like @Chipper5783 says, there is usually a way to do it. Sometimes, you just stare at it for days till the light bulb comes on. "This problem too will be simple when solved."

Your friends advice is valid. But I wouldn't let it stop you. There is always a way.

 

[terry_g]

I have a 3 jaw and 4 jaw mounted on D1-4 back-plates with no problems.

 

[thestelster]

I have a D1-5 which has 6 studs. A bigger diameter but in other ways even harder to do. I think I have mounted or built 6 chucks now.

It is ALWAYS a problem. But like @Chipper5783 says, there is usually a way to do it. Sometimes, you just stare at it for days till the light bulb comes on. "This problem too will be simple when solved."

Your friends advice is valid. But I wouldn't let it stop you. There is always a way.

The Accusize D1 backplates for 4jaw chucks seem to be extremely thick, specifically for that interference issue. You'll have to measure and determine if it will work for you.

 

[Susquatch]

The Accusize D1 backplates for 4jaw chucks seem to be extremely thick, specifically for that interference issue. You'll have to measure and determine if it will work for you.

This is one of the few times I've ever disagreed with @thestelster. If you measure first, you will get discouraged and quit. Just buy the damn things and count on your creativity to figure it out. Or post what you bought here and we will help you.......(especially @thestelster ! LMAO! )

Also, I've found that Accusize often has several choices of backplates - often thick or thin. Thick is definitely good for this issue! Then again, thin often allows another secondary adapter.