Home made quick change tool post QUESTION

[Paul_Pfeiffer]

I am working on the tool post by Stevenson.
http://www.metalwebnews.com/howto/toolp ... lpost.html
I think I have figured out that the centerline of the wedges should be close to the centerline of the spindle. What does anybody think? I am putting this on my 9" SB. The height from the top of the compound slide to the centerline of the lathe is 1.050". I especially want to hear from the ones who've tried making their own QC toolpost. Paul P. [img]/ubb/images/graemlins/cool.gif"%20alt="[/img]

[curley]

Paul, I too, used John Stevenson's drawings for my 14" Ajax and all that I did was increase the total height to reach! I think John is the one to answer if that dimention is importand or not. Perhaps he will jump in here and let us know. I can't recomend this unit highly enough. I had used at least 3 other tool posts and I just thought my tool was ridgid! The only "trouble" that I had was on the first female dovetail cut. I guess I missed the position, because I cut into the head of the screw that guides the wedge, still works ok. I just made sure I missed it on the other side. I'm sure you will enjoy making the unit and a bunch of holders, and I know you will love using it.
Regards, Curley
P.S. BTW, thanks a bunch, John.

[John_Stevenson]

None of the measurements other than the internal / external dovetails are critical on this project.
Although the original was designed for a 3 1/2" centre hight lathe the whole idea was for people to scale up or down as nessesary to suit their lathes.
I now have the same design on three lathes of 5", 6" and 7" centre hights, all that differs is the overall hight and the stop stud on top so any tool holder interchange between all three machines.

The reason the wedges were placed on centre hight is to try to centralise any wedging action. It's not that critical either as you can't guarantee where all the holders will be in relation to centre as it depends on the tool hight.

John S.

[sergi]

I respect anyones desire to make their own stuff, sure.
BUT, when you can just buy this:

http://www.use-enco.com/pdfs/202.PDF
505-2253 251-100 SERIES 100 QUICK CH. TOOL HOLD. SET 202 $89.95

you have to ask yourself wether you really can afford NOT to [img]/ubb/images/graemlins/smile.gif"%20alt="[/img]

IMHO, if you still think it worth your time to make your own, your lying. Now, you may very well want the SATISFACTION of making you own, but that's a whole 'nother thing. [img]/ubb/images/graemlins/smile.gif"%20alt="[/img]

[John_Stevenson]

Sergi,
I looked at the site you mentioned and I could only see this one listed at 189.95 and not 89.95
Added to this the one you have picked out is a piston type and not a wedge type. The piston type is very inferior to the wedge type in holding power and repeatability.

In my case it WAS worth the time, and I'm not lying.
I have three posts all of the same design and all matched so that a holder will fit all three machines and still be on centre.
I now currently have about 45 holders, most made in sticks of 5 or 6 pieces to save time. All of which will fit three machines from 10" to 14" with no messing.
See:-
http://homepage.ntlworld.com/stevenson. ... olpost.jpg

Some of these like the knurling tool, the big circular parting tool and the chaser insert holder are all specials. None of these are available at any price.

I never kept record of time spent on these but as I incorportated them in with other similar setups the time wasn't as great as doing them from a dead start.
What I can say is running a small workshop for a living, full time, this setup has more than paid for itself over and over again in time saved.

John S.

[davestea]

Steve -

The Jan/Feb Home Machinist (center fold 43% off) Enco ad has the Phase II QCTP with 5 tool holders for $89.95. This xd502-2253 (regular price $160) - 2002 catalog $140.

It shore duz look like the same one I got from HF on sale (reg $99) for $70. And I got a drill chuck and arbor along with it all - slides real nicely into the boring bar holder.

I note that your tool holders have 'male' DT while all the comercial ones have a Female DT. Is this significant? Like maybe since one only needs one tool post, is the male side easire to cut?

Are any of these similar units interchangable or are they just far enough different not to be usable on another post?


What's the crossed bolts tool in front of the knurling tool.

[John_Stevenson]

Dave,
The reason these are inverted is as you have guessed. Normally you only make one toolpost so I wasn't bothered about the work going into this as I wanted the holders to be as simple as possible.
I make the holders on a horizontal mill and with a 60 degree cutter angled cutter I run down a long length of steel, turn it over and run down the other side. That makes me a stick of holders that they just need sawing off and the tool slot or hole in a boring bar's case, milled in.
I can blank a dozen holders out in about an hour.

The crossed bolts in the foreground are the wedges out of the the post also in the foreground. One is left at full diameter and a 3/8" slot milled thru and the other is turned down to 3/8" to allow the wedges to cross over on the same centre line.

The drawings and a better write up are in the Metal web article that is linked in Paul's first post in this thread.

John S.

[sergi]

burning the midnight oil ? [img]/ubb/images/graemlins/smile.gif"%20alt="[/img]

I bought the wedger type for 180, the piston type is 90.

anyway, that's an impressive # of holders you have there, and with a big bar of holder stock that you can cut to length I can see how that would be handy and relatively quick.

but for 180, there is no way I could build a wedge post and the 5 assorted holders that came with.

not to say it isn't worth it to make a tool post and holders vs not having one but commercially produced items almost always cost less than the time it takes a individual to replicate. that's all I'm saying. And I can, (and have) made some of my own attachments to use with my axa toolpost. it's nearly as simle, the dovetail is just the other way around.

[John_Stevenson]

Sergi,
I do have to agree with you on the value of these items.
In hindsight it would pay to buy a set and make new holders to suit if you are happy with the inversed dovetail.
In my case checking the original article it had a 1994 copywrite date but this was only the web article. I had a job change in 1990 and I can remember making my first whilst at the old job. This would date the design to about 1987 or 88.

In those days [ faint sounds of violins playing ] the only quick change posts were the Dickerson type at a lot more money than they are today. There were no import parts such as these so my design was ground breaking in being simple and cheap.

I know quite a few were built in the early days but these have got to have tapered off due to the imports.
They still apeal to some folk who have far more time than money.

John S.

[JimGlass]

This is my version of a quick change tool post I made 3 years ago and still use. I'm using a 1/4-20 SHCS for clamping.
Clamping pressure is uniform and balanced through the dovetail.
Jim

[Paul_Pfeiffer]

Thanks to all for your in put, esp. John Stevenson. What a great design. I am definitly in that category. Much more time than money. I have waded into the cutting. I have been "helping" a friend get some projects out the door at his shop, and getting some lessons and cut-off saw time in return, and a bit of paycheck in return. What a deal. Someone is PAYING me to do this! I would probably to pay them, esp. for the lessons I am picking up along the way. I digress.
So anyway, I have a post and one wedge partly done, and blocks cut for 12 holders, and several more toolposts. My ultimate goal is to build a Live Steamer for the back yard. 9" lathe, 7" shaper, 12" drill press. Paul P.