Quick change toolpost

I currently have one of these **LINK**

Following on from my parting off woes, I have concluded that it’s not the best. I have noticed that I often have to keep re tightening the tool holder to the post, the slightest jar loosens it.

I have read up a bit and the consensus seem that wedge type holder are better than piston type.

Therefore I am considering one of these **LINK**

Anyone use one and are they any good

Edited By petro1head on 13/10/2018 12:56:04

I'd be looking into why yours won't hold tight. I have a similar Dickson on my 280 and that stays tight enough and I only use my chuck key handle as a tommy bar not a long spanner. maybe blue the two mating faces to see if one is not flat or is the thread on the post stud not long enough so you are going tight against that rather than the post itself.

Did you modify it yourself or get the Warco machined one?

Edited By JasonB on 13/10/2018 13:11:33

Well I could but to be honest Jason, I just don't have the time to try to find out why it does not work, just need a replacement as I have a job to do for a friend

So you have known all along that the tool comes loose and causes the veering-off fault?

No, but now that I think about it its the only thing that can be wrong

Right, so the veering-off only happens if the tool loosens?

The 222 is blooming enormous!

I've used the somewhat smaller 100 (piston) and 111 (wedge) on a 4" centre height lathe and they are both excellent, and beautifully finished too.

You might want to consider the smaller size.

Neil

The Dickson type that you have should have a hole through it to fit a dowel into the topslide to stop it rotating. I have a similar one on my Myford and needed such a dowel to prevent slight movements which play havoc when you are trying to reference multiple tools.

In fact your photo shows the hole at the bottom right of the holder in its normal operating position.

Edited By John Haine on 13/10/2018 14:06:10

Reading again it seems it is the holder coming loose on the toolpost not the whole post coming loose. Two reasons this can happen and at least one is a 60 second fix but as you don't have the time I'll leave it to others who have used the alternatives.

Also see my last comment on the parting post

Edited By JasonB on 13/10/2018 14:23:58

Is your friends job that urgent and even if it is, it is going to take you until Tuesday from today to get a replacement. Surely its worth trying to sort the problem, you may find it an easy fix plus it seems a pity to condemn it without trying.

Jason, Ron

Sorry if I was a bit curt, this has frustrated me and to top it off my phone has stooped working so feeling a little frctious.

Your both right, a little time ti sort it is probably worth while and my friend is happy to wait, so fire away Jason

Neil, thanks. I was going to ring Arc and ask what size to get. My lathe is 300mm swing

I use a "222" on my Chester Crusader (Ø300mm swing) and a "000" on my Sieg SC4. Both are perfect size.

I could have possibly got away with a "111" on the big lathe, but most of my tools are 16mm shank.

Going over to a wedge QCTP has transformed the tool holding.

Jim

PS Neil my centre height is 5"

222 Series set w/5 holders
Fits up to 10"-15" Swing Lathes

Edited By petro1head on 13/10/2018 16:40:35

Ah, the 200 won't look stupid on a lathe that size!

Ah 10" lathe... that#'s 250mm swing - you might find the 100/111 are better suited.

If you contact Arc, let them know the thickness of the bottom of your standard toolpost.

Neil

Edited By Neil Wyatt on 13/10/2018 16:51:32

I don't understand why you are so keen to spend more money on another TP system when the Dickson type works fine if properly adjusted and clamped.

This is mine, bolted down firmly to a machined base on the crosslide. You can't see it but there's a 6mm dowel through the hole in the top surface into the base casting to stop the block rotating if the clamping isn't enough. I've never had a problem with the clamping of the actual tool holders on to the block but it is a well proven design and as Jason says probably a simple adjustment. You may be surprised just how hard tools and their holders need to be clamped to avoid movement under cutting forces.

Sorry Neil, confused

Edited By petro1head on 13/10/2018 17:56:03

Well I fear I may have upset Jason, who was going to tell me the fix

Need to take a couple of pics to illustrate the problems, now I've had my fish & chips I will go down to the workshop.

petro1head, nothing all wrong with Dickson style tool posts, I have been using them since they first appeared in the early 1960's on many different lathes for DSG, Smart & Brown etc down to my Myford and Emco S11-- never had a problem with my original Dicksons. For parting off I use the bog standard HSS tool in the standard holder on both machines.

However there can be and often are problems with the imported clones particularly if the tool post and holders are from mixed sources. Generally they can be resolved by adjusting the tool holders -- best not to tamper with the tool post unless it is defiantly at fault. Not impossible but unlikely if its genuine one.

I have found some clone holders do not fit and thus lock properly on my original tool posts so have had to modify them. It sounds to me there is something wrong with the locking cam that pulls the tool holder onto the toolpost and would recommend you investigate this first.

John

Chief suspect I agree, but you also mentioned that you can't operate the lock because the DRO is in the way. That looseness won't help either. When parting off rigidity is important.

Dave