Hi David

I bought a A2Z toolpost from littlemachinshop for my SC4.

It's a direct fit and the right size but after using it a few years I find it a bit light and flimsy.

Maybe a Dickson style toolpost would fit.

Yngvar

He did!! Ian S C

Have a look at the picture in this old thread. He is using a myford one. Be aware that on another thread a shortage fo toolholder is being reported.

Also must say that as a beginner you don't need a QCTP. Even as an expert you don't. If you are in a tearing hurry beccause of all your trips to London it might help. It is for making quick changes in a jobbing shop not for improving your machining.

Edited By Bazyle on 30/07/2014 13:40:04

IMHO quick change tool posts on small machines are not, perhaps, as satisfactory as might ideally be hoped. Although all engineering is a compromise, the art being to get the performance you need at a price you can afford with the minimal number of work arounds where real life collides with infinite desire, small QC systems on small lathes can leave the feeling that everything in your favour is against you. Of necessity QC tool support is indirect, round the corner, and via extra sliding joints when compared to a bolt down type. Given that the objective is to present the tool rigidly and accurately to the work the QC system inevitably compromises tool mounting stiffness which is acceptable providing there is enough stiffness left. With a small machine all the components, both in toolpost and lathe are disproportionately weaker than with a lager machine soley by reason of their small size. Affordablity in relation to amateur pockets is a very important consideration inevitably ruling out sophisticated design and close tolerance manufacture which might otherwise help overcome the limitations of small size.

Given that you have already decided that a QC set-up is within budget if a suitable one can be found its worth seeing if there is a way of getting most of the benifits of a QC set-up without loosing the stiffness inherent in bolt down systems. In the past I've found an economy "fairly fast" change toolpost system based on interchanging 4 way tool posts to be adequately satisfactory so maybe a refined version would work for you.

In practice you rarely manage to get more than two tools in the small four ways so I'd suggest 4 will be needed. Cutting up beer cans to shim up on the machine is, as you have found, unsatisfactory. It should be fairly easy to devise something to let you set the tools to centre height on the bench, preferably at a constant projection. A modest investment in known size shim stock, I'm told that the colour coded pastic type works well, and sheet metal spacers, worn out and de toothed hacksaw blades can be handy, should make the whole setting process pretty painless. Especially if you can spare a dial gauge or other measuring device so as to know exactly how much shim to add.

Best to fit a rear toolpost mount whilst you are at it then the parting tool and a simple flat top round nose 45° point facing / chamfering tool can live there. Satisfactiory basic loads for the other post would seem to be :- roughing tool & finishing tool, boring tools large & small, threading tools inside and outside. Depending on the machine and detail 4-way design you may need some low cunning to get really satisfactory indexing for the 180° shifts needed on the front tools and the 90° one on the back but nothing seems unreasonable. Obviously you may need to change the specific tools for different materials or for tricky work. I recommend that you grind the angles on the tool rather than pivot the holder to make one tool do several jobs.

When sharp and well supported the simple flat top facing tool works remarkably well. It may be easier to make a U section carrier into which the facing tool and its necessary shims can be clamped via suitable grub screws so the rear four way doesn't have to be disturbed after sharpening that tool. If you want to stick with one four way such U section carriers could be made for all the tooling if arranged so that the could be swopped in and out of the four way without altering the projection. If using simple HSS bar for tooling it would be advantageous to make the U with a built in up kick as used on Armstrong style holders so height can be set simply by varaying the projection. The amount of fuss and effort needed to produce the necessary quantity of U sections is deceptive and a considerable effort. Multiple 4 ways is much easier.

Clive

David,

Although not critical for operation of your lathe, a QCTP makes things a lot easier and quicker. In "normal" turning you invariably end up having to change tools, fairly regularly. I found that a 2, 3 or 4 way toolpost tends to get in the way. Be aware that others use tangential tools which seem to work as multi-purpose tools covering many different operations, so a tangential tool might be a useful one to have in your arsenal – though I don't have one and use a QCTP.

There are simple free toolpost designs out there which could be made on a lathe – though a milling machine does help – I suggest you investigate them. Obviously you start off with a couple of holders and make more as you need them – but beware – you need at least 2 spares as you'll always find something else to use with them, e.g. I have one for my DTI, one for my knurling tool, and one I use with a fine slitting saw for chopping up small metal sections (saw in the chuck and stock in the tool holder)!

Would I go back to a normal toolpost now – no way!

Regards Tom

I disagree. Our small machines are very critical on tool sharpness, height setting and so on, especially at the small sizes that are common, in our miniature machining. As a result we need to change tools far more frequently than in for instance a jobbing shop.

Continually shuffling shims, and generally pratting around just trying to get a tool to the right height is a major disincentive to a happy life.

Get a QCTP !!

cheers

Bill

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Beware of Dickson 'Clones' – Not all clones are created equal.!

I had a clone that was about as much use as a chocolate fireguard.

Nick

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That is your prerogative to be offended if you so wish. It's a free country. (I think)

Perhaps I should have said "Some clones". But I did think I had made that clear by saying they were not ALL equal.

The clone I had / have was so bad I have not even got the gall to shift it on via ebay. It came from RDG and I stand by my 'chocolate fireguard' statement. – But I am willing to except that I 'may' have got a bad one. It has been shown to a few other members of this forum and a pro engineer. All were appalled.! When I first got it I was a total newbie and knew no better. If were to be delivered it now I would send it straight back. ………….. We live and learn eh.?

I did not blanket condemn on mass the style and technology of all Dickson clones. I just urged caution as I know I am not the only one.

Have a nice day.

Nick

EDIT – having reread your post I think you were speaking in jest about 'chocolate fireguards' – Oooooooops, sorry. 

Still have a good day though. 

Nick

Edited By Nick_G on 28/01/2016 13:55:33

I wonder if it's worth buying a Dickson tool post, perhaps second hand, and then buying "cloned" holders? I'm lead to believe the better copies are interchangeable with the real thing?

Funny how old posts get brought back from the dead …

No-one needs a QCTP but once you have used one for a job that needs multiple tool changes, you will bless it every time you use it.

Mine is the most useful accessory I ever bought or made