Holding short lengths

Afraid I don't understand what all this c---p has been about,nor why we need another marathon series on short lengths.. For 99% of us who are happy just to get the job done the solution is pretty obvious ,ERs, and if some lucky model engineer has a machine that is powerful enough that these give problems then reduce the cut,or is this too easy ? Judging by the "Guhring " video any cut classed as just short of "Brutal" should not be a problem.

For the small number who are reading a model engineering site but are involved in production then reducing the cut may be less welcome and increase machining time and cost. However if they can't analyse their problem and come up with an alternative method of work/tool holding they should n't be in the business of producing metal parts,and probably won't be for long. So who has a problem ? No one, except production machinists who should know enough to solve their own problem . In other words no one has a problem. Model engineers can't produce the problem and those who can should know the answer.

i do find it instructive that Mr. Stevenson has typically ,IMO, offered to come up with, and will no doubt do so, a solution to the problem for the amateurs who are determined to spend their time machining short lengths but refuse to adopt the recognised and simple solution.

JS,I know, has his own Swinglite (and is no doubt a black belt in its use ) and does n't need me to defend him. However it is probably easier for me to say that in my opinion he is far from an ordinary machinist in that his bodges are actually far from bodges and demonstrate good lateral thinking in solving engineering problems that benefit and amuse us all. Also I have for one gained great benefit from his willingness to take the trouble to write up and publish articles on solving model engineers problems e.g. taper turning using a boring head, making gear cutters etc etc. When you add to this the extraordinary efficiency and effort he put into taking up the Chris Heapy site and ensuring its survival, the improvements he has instigated in simple accessories at Arc, and his work at exhibitions sharpening for a charity fee and not least the improvement in the general tenor of the posts on this forum since he became a moderator I can think of few others who do more for model engineering. I speak as one who's efforts in eliminating rivet poverty in the UK failed to be recognised by the Palace.

I could add more but will limit his embarassment. I felt compelled to add this paragraph in view of some extraordinary posts submitted recently. Not that JS is above criticism . I have in the past taken serious issue with him when certain items have been rapidly sold on another website he has connections with ,without his checking with me first as to whether I required the said items . I'm never more than a phone call away. I also never proved anything but there was a time long ago when QCTPs hardly ever appeared on the aforementioned website and I often wondered whether he was trying to corner the market in QCTPs and holders in order to hold us all to ransom. I believe he has more than a few.

Alan Frost (brown belt , pink Swinglite,green engineer)

Edited By alan frost on 27/09/2016 15:15:25

If I could be forgiven a short commercial,apart from my unrecognised (but successful) efforts in eliminating rivet poverty in the UK , I now have the means available to commence the project to eliminate ball bearing poverty amongst model engineers in the UK. I know this was one of the major concerns of the Cameron government and as soon as I can get off my backside and classify the bearings adverts will be flooding the country. Toyota at Derby and Honda at Swindon (or is it the other way round ?) have now been satisfied and we now have capacity to release bearings to the model engineer market . As Theresa said to me only yesterday "Thanks, Alan,thats one less problem to lose sleep over".

If you don't understand any of it then fine, you work you're way and I'll work mine. simple .

<redacted>

If you can't be constructive like others, please don't clutter up the thread with inane ramblings. This thread has got zero to do with QCTP's, Ball bearings, or Camerons government.

Edited By Neil Wyatt on 28/09/2016 21:06:15

Sorry if I sounded a bit terse Michael. I was busy with other things so it might have come across a little rude.

Any way all I was getting at is some seem to think that metal has a similar characteristic to rubber which it has but nothing like to the same extent so that if loaded reasonably it can be ignored. Good job too.

The contact aspect is a little more tricky. Say something is in contact and another isn't by 1um and that could be due to a number of factors. Is it gripped so well ? Yes and no depending on finish but clearly as some relatively low level this does matter.

The up yours was just a joke. It comes from having had to explain a number of things to people at times over a large numbers of years. It can be a thankless task in some respects especially when some one is totally locked into their own ideas on a subject.

John

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Alan, Have you ever felt the weight of a 12" chuck on a DSG? That is where the collets are going and they will be on there long term. Not everything needs a 12 " chuck. I don't mind swapping over the 6 " on me GH750 to ER 40 I do that quite often, but there is a very big difference in weight.

Jason, Steve1, I have made a decision, and am going for the 25c both through bores and there are also emergency ones that can be machined to suit.. Just need to fire off an amended e-mail to Hardinge about the spindle nose [since I have decided on 25c and not the original 16c] I would be just as well to go the full monty and make use of the DSG spindle capacity. rather than regret it later. Be a lot of overtime done to pay for this.

Thanks for all your constructive help.

cheers

Raymond,

Please do let us know what D1-8 25C chuck you go for.

To answer the now redundant question about the 5C sjogren chucks, they used to be made by Hardinge and perhaps others before then but I think they don't make them any more. That line of product was sold to ATS workholding.

**LINK**

Steve

Funny enough Steve I was just looking a guy using the 5C step collets and it looks like he has one of those chucks or something very similar.

**LINK**

Raymond you may be able to get away without teh external rings on the sort of sizes you are looking at, its more the big ones that grip better with the load applied at the outside.

Edited By JasonB on 27/09/2016 17:16:02

Hi Steve1, Jason . First off thanks for all your help with this, it is much appreciated. I have sent an amended e-mail to Hardinge in the UK changing the spec from 16c to 25c As soon as I hear back I will post on here.

Did a quick count up of the collet prices on the us site and they are all in dollars, so a quick conversion resulted in a definite arm and leg scenario, plus I still have to get the price of the chuck !! I think the DSG would warrant it anyhow,. and it will be a once in a lifetime purchase... so best do it right .

Will be quite a bit of overtime done to pay for this thats for sure.

cheers

Just had a look at the speed chuck and it looks a cracker, and is available in D1-8 so no probs there.

I tried the Harding catalogue but could find no reference to 22J Collets although the ATS chuck info says 57.15 capacity. Will see what Hardinge says re the D1-8 for the 25c. If that is a no go then at least I can have the speed chuck in 22 J, that would be a fine replacement.

cheers

Jason,

That video link does indeed look like it might be a sjogren speed chuck. However it has the plain nose so you can't use the closers on it. I always use the closers since I have them and I don't fancy any mishaps. Looking at the step collets I have they will contract with out a closer a little but I can't see them working as well as with the closer. I hope he stays lucky....

Raymond, the speed chucks come in various flavours, 5C, 2J, 3J, 22J etc. For the 5C they come in the 3 variants.

with the plain, taper, and threaded noses. I only have experience with the 5C-X type. The hardinge website is not the easiest to navigate but this link should hopefully take you to the 22J collets:

**LINK**

I don't have any experience with 22J so I can't comment on the suitability.

Edit for spelling errors

Edited By SteveI on 27/09/2016 18:00:43

Which DSG have you got Raymond ? I did a lot of work on a long bed toolroom version in pristine condition years ago. Wonderful machines. I almost feel like crying when I see some examples on ebay. How dare they get a lathe like that into the sort of condition they sometimes are.

The answer to the big chuck when I worked on lathes like that was a wooden block that the chuck can't roll off that bought it up to the correct height and aligned it well enough. It took a bit of effort to slide it along. At that time I was perfectly capable of handling big chucks - not so sure now. Gravity seems to have increased.

There was a big Lang about as well. Deliberately mall adjusted but not used much and never for long. Adjusted up it was nothing short of fantastic. I have seen which is best DSG or Lang arguments about. CVA's can be pretty amazing too. They also did a CVA with gap bed with a huge swing in it. It seems they based it round one of their spinning beds.

John

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Raymond,

I sent you a p.M. earlier

MichaelG.

Just received an e-mail from ETG Workholding [they must be agents in uk for Hardinge ] They can supply a 25 c chuck in D1-8 camlok fitting. They are making up a quote for the following, 1 set 25c collets from 30mm to 65mm [they actually start at 15mm but I have the ER40 on the GH 750 so will start from 30mm] 1 chuck and the prices of individual "emergency " collets. I will just make sure that I am sitting down when I open the quote .

cheers

Raymond,

I think last year Hardinge outsourced some of the UK operation as the shophardinge UK website suddenly turned in to ETG Workholding. The prices went up as well, and the UK shop was already more expensive than the USA shop.

I've seen that amazon.com (.com not .co.uk) carry most of the Hardinge collets and are the same price as the USA shophardinge.com prices.

You have bad timing on this with the recent loss of value of the pound to the US$.

Steve

Hi SteveI , Thats typical... the rear end falls off the £ against the $ when I wanted it stronger . Still I will make sure I have a strong seat and the oxygen mask at the ready when I receive the quote. Once I am up and running I will stick some pics in an album.

cheers

Ps will go have a look at the Amazon site.

Edited By Raymond Anderson on 28/09/2016 15:20:52

In an attempt to extend this thread to five pages, has anyone ever mentioned Bell Chucks?

For those who are not familiar, there are Internal and External versions, each one covering a range of sizes, in very small increments, capable of holding work as short as about 1/16" (1.5mm).

(Used a lot by the horological community, I believe) I obtained a set, (Not that I am capable of making a clock), but they come in useful for thinning washers. They would be ideal for the criminal offence of defacing coins of the Realm!

Mine, are Imperial, and will probably hold very short lengths, upto about 55mm dia .; depending on which of the multi stepped ones you use.

You just need to be careful not to run the tool into the very hard body.

Like so many tools, not used frequently, but invaluable for the odd unusual job, when it arises.

(I am sure that John S has many such bits and pieces for just such occasions in the course of his day job)

Howard

The 5C step chucks that we have been talking about are basically bell chucks, if you look at that last video I posted the one shown closes like a bell chuck but teh larger ones have a tapered closer that applies the pressure on teh outer dia.

.

Jason,

Just for info. ... the horological equivalent typically has multiple steps: **LINK**

http://levinlathe.com/StepCollets.htm

Obviously only suitable for very short workpieces.

There is also a 'ring holding' version, which is rather clever

http://www.nielsmachines.com/en/lorch-las-llk-lan-step-collets-set-and-ring-colle.html

MichaelG.

Edited By Michael Gilligan on 28/09/2016 15:53:25