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enginuity
08-06-2017, 01:35 PM
I completed my quick change tool post based on Metal Lathe Accessories' MLA-23 toolpost last week. It was scaled down for the 8" swing on the Schaublin. The original design might have been a bit large being designed for 9"-12" lathes, although it may have worked. I made a number of other changes as well. Here is the CAD model:

https://thecogwheel.files.wordpress.com/2017/05/toolpost.jpg

Here is the finished product:

https://thecogwheel.files.wordpress.com/2017/08/toolpost_finished.jpg

All the bits and pieces:

https://thecogwheel.files.wordpress.com/2017/08/toolpost_pieces.jpg

I made a build video of the entire toolpost:


https://www.youtube.com/watch?v=8d7xY4UNGAg

https://www.youtube.com/watch?v=8d7xY4UNGAg

I'm very happy with how it turned out. More importantly I'm very pleased with how well it works.

mattthemuppet
08-06-2017, 06:09 PM
That looks fabulous! Does the whole post move when you release the tool holder or is it matured to the compound?

Paul Alciatore
08-06-2017, 07:05 PM
Yes, it looks neat, but does it repeat? To me, that is a main concern with a tool post. Quick change or not if it does not repeat then 90% of the value is lost. It does not take a lot of time to slap a new tool in a lantern style post and just lock it down. The time is consumed (and wasted) in setting the tool height and position. You appear to have a screw/nut for height, but what about position?




That looks fabulous! Does the whole post move when you release the tool holder or is it matured to the compound?

dalee100
08-07-2017, 10:33 AM
Hi,

Nice work! It should do well on your Schaublin. Got to start making more tool holders now.........

I looked at that design when I made my tool post. Two things that didn't really work for me was the single tool position, (I wanted fast 90 indexing), and I was concerned about the locking method. I wasn't sure about the cone being able to spread the dovetails evenly top to bottom. I was concerned that it would spread more at the top, allowing the tool tip to possibly rock up or down a bit under load. And this getting worse with wear. Have you noticed any possibility of this?

enginuity
08-07-2017, 10:52 AM
That looks fabulous! Does the whole post move when you release the tool holder or is it matured to the compound?

Thanks Matt! It was fun to do, and I learned a great deal along the way. I would definitely recommend a build like this. Yes you can buy the toolpost for much less than what you would have into it, but you don't learn very much that way. The whole post moves when you loosen the handle. It is free to move in height and rotation.

enginuity
08-07-2017, 11:00 AM
Yes, it looks neat, but does it repeat? To me, that is a main concern with a tool post. Quick change or not if it does not repeat then 90% of the value is lost. It does not take a lot of time to slap a new tool in a lantern style post and just lock it down. The time is consumed (and wasted) in setting the tool height and position. You appear to have a screw/nut for height, but what about position?

The toolpost repeats in height, which is the real problem in my opinion with the lantern style. That and the lantern style lacks rigidity. This post is very rigid.

While for many the repeatablility in rotation is an important feature, for what I do it is not. I do lots of one off and prototype work with occasional production type stuff. If I was making a batch of 20 parts I would want angular repeatability. But even then that requires me to remember the cross slide dial's settings as I don't have DRO. If you have a DRO then the tool being in the same angular position every time is very important.

For a lathe that doesn't have a carriage I doubt I'll ever put a DRO on. If I want to lock it at 0 or 90 degrees there is room on the compound to add something to do this. There is room in the design to add graduations to the body so that it acts like the compound and you can set the angle with a scale. So far I haven't needed this, but I might add it.

But what I find a pain is setting tool height. This post takes care of that.

Toolposts divide many into camps. I suppose you could debate all day. For me rigidity and tool height were the 2 primary factors. Plus it had to suit the Schaublin from a design and aesthetics perspective. Someone vain, I know, but it is a hobby :).

enginuity
08-07-2017, 12:54 PM
Hi,

Nice work! It should do well on your Schaublin. Got to start making more tool holders now.........

I looked at that design when I made my tool post. Two things that didn't really work for me was the single tool position, (I wanted fast 90 indexing), and I was concerned about the locking method. I wasn't sure about the cone being able to spread the dovetails evenly top to bottom. I was concerned that it would spread more at the top, allowing the tool tip to possibly rock up or down a bit under load. And this getting worse with wear. Have you noticed any possibility of this?

Thanks!

The toolpost is still new, but it is exceptionally rigid. I don't notice a difference in rigidity in regards to where the tool holder sits on the dovetails of the post. I think more importantly here is making sure the dovetails are parallel.

I know Andy uses this post a great deal in his shop and he says it is still very good. Nothing is hardened on his toolpost (or mine) and it doesn't seem to make a difference.

I do need to make some more holders. I plan on making all of my own, but you could easily adapt the post to allow 0XA holders to fit.

BCRider
08-07-2017, 01:22 PM
H......I wasn't sure about the cone being able to spread the dovetails evenly top to bottom. I was concerned that it would spread more at the top, allowing the tool tip to possibly rock up or down a bit under load. And this getting worse with wear.....

I wondered about this too when I first saw the 3D sketch. But I, like I suspect you are doing, figured that the cone would be located closer to the top. But really it's well down and the middle of the cone looks to be roughly located at the middle of the body where the big majority of the holders will seat.

It does suggest that to make this work for a specific machine that some consideration be given to that actual machine and where the majority of the tool holders will rest. Then adjust the depth of the conical seat in the body and length of the wedging cone to suit. That would avoid any concern over this issue

thaiguzzi
08-07-2017, 11:43 PM
# Always liked the MLA design.
# Single tool position is no problem for me, in fact i prefer it to my Dickson copy (Bison) 2 position tool post holder (bulkier). I really like the lack of bulk, but still has very good rigidity.
# Radial position repeatability could be done with a simple fixture or some graduations on the round base.
# I prefer this round design to the original square one.
# Very nice job OP.

vpt
08-08-2017, 08:43 AM
Video and tool post is nicely done!

Do you only have one backing plate for your chucks or is that how the lathe just is (can't remove backing plate)?

Glug
08-08-2017, 09:25 AM
In the late 90's, I made my AXA tool holders for my Dorian QC tool post. At the time it was an invaluable learning experience, and it was my first serious project on my Tree mill. Power tapping without a tapping head, slotting, dovetails, knurling.

Having 20 of them to mount my large collection of HSS was fantastic. I made them three at a time. My only regret is not making more, and making blanks. If I did it again, I'd cut the tool slot about 3' long in the bar, and then I'd do a setup where I cut the dovetail in 15 holders or so at once (rather than the 3 I did).

vpt
08-08-2017, 09:59 AM
My only regret is not making more, and making blanks. If I did it again, I'd cut the tool slot about 3' long in the bar, and then I'd do a setup where I cut the dovetail in 15 holders or so at once (rather than the 3 I did).



Thats what I would do if/when I have to do it again. But in my defense I didn't have my mill at the time I built mine originally.

J Tiers
08-08-2017, 10:47 AM
I see you used the spiral type taps, and by hand at that. I see them extracting the cut material perfectly. Dunno how you do that.

When I used the ones I have, they just did not work well, definitely not by hand, and not well by machine either. At least I did not buy them myself, they came to me in a box of stuff.

Mine are a shallower helix, though. They seem to expand and either cut oversize, or jam. I have not quite gotten to tossing them in the steel scrap/swarf bin, but I still might, even though they are basically new, and sharp.

Nice video, and toolpost, though!

lakeside53
08-08-2017, 10:56 AM
I have a number of high end (Nachi etc) spiral flute taps that I use by hand in blind holes. I've never had an issue with them - usually get 2 or 3 (flute dependent) lengths of swarf spirally out of the top (just tap forward - no stop-reverse-go type actions) . I'd buy more but they are too expensive and are a bit more fragile then I like for general use. I've never busted one, but I take great care. Spiral tip is my usual robust go-to choice


Nice work on the tool post!

engineerd3d
08-08-2017, 11:31 AM
I am interested in that level you have. How accurate is it? Model and brand would be nice too.

mars-red
08-08-2017, 12:44 PM
I completed my quick change tool post based on Metal Lathe Accessories' MLA-23 toolpost last week. It was scaled down for the 8" swing on the Schaublin. The original design might have been a bit large being designed for 9"-12" lathes, although it may have worked. I made a number of other changes as well. Here is the CAD model:


Awesome work as always, Justin! The toolpost and the video came out great.


Video and tool post is nicely done!

Do you only have one backing plate for your chucks or is that how the lathe just is (can't remove backing plate)?

I don't think Justin will mind too much if I answer for him. :) (if he does mind, I give him permission to punch me in the face during the next podcast, lol) The backplate on that machine is part of the spindle, I used to have a machine that was the same way. Changing chucks was a royal pain, had to use a shortened allen key that just fit between the headstock casting and the rear of the backplate, to remove and reinstall the screws that go in from the rear.

enginuity
08-08-2017, 01:07 PM
# Always liked the MLA design.
# Single tool position is no problem for me, in fact i prefer it to my Dickson copy (Bison) 2 position tool post holder (bulkier). I really like the lack of bulk, but still has very good rigidity.
# Radial position repeatability could be done with a simple fixture or some graduations on the round base.
# I prefer this round design to the original square one.
# Very nice job OP.

Thanks! I was thinking about graduations on the round base. It was planned for ... I might do it.



Video and tool post is nicely done!

Do you only have one backing plate for your chucks or is that how the lathe just is (can't remove backing plate)?


The backplate on that machine is part of the spindle, I used to have a machine that was the same way. Changing chucks was a royal pain, had to use a shortened allen key that just fit between the headstock casting and the rear of the backplate, to remove and reinstall the screws that go in from the rear.

LOL, Max is right about the backplate is part of the spindle. It is a pain for changing chucks, but is probably a bit better than a threaded spindle if you want to run in reverse. I don't like it, but I don't completely hate it. A nice camlock would be appreciated. In this case they did it to obviously save cost. There is a register machined into the spindle for the chuck but it is not very large.




I see you used the spiral type taps, and by hand at that. I see them extracting the cut material perfectly. Dunno how you do that.

I've never had any problems with the spiral flute taps. In fact they are all I buy anymore (YG brand to be specific). The really small ones you have to be careful with as there is a lot less material than the equivalent 'normal' tap, but they always cut nice. Maybe it is the brand?


I am interested in that level you have. How accurate is it? Model and brand would be nice too.

I can't quote you the accuracy, but it is reasonable it seems. It is definitely not to be compared to precision levels, but I like it for quick and dirty angular setups (like what I did). This one is a Mastercraft branded level (from Canadian Tire - a store unique to Canada. For those how are unfamiliar Canadian Tire is sorta like Sears, sorta like Pep Boys, sorta like Walmart etc. A lot of cheap Chinese crap anymore, but some interesting stuff). I'll have to look around to see if there are other versions. I'm sure there are - Canadian Tire just gets their stuff rebranded.

J Tiers
08-08-2017, 01:43 PM
,,,
I've never had any problems with the spiral flute taps. In fact they are all I buy anymore (YG brand to be specific). The really small ones you have to be careful with as there is a lot less material than the equivalent 'normal' tap, but they always cut nice. Maybe it is the brand?


...

Yours do look different. I'd show a pic of mine, but I don't have a new host yet. The spiral flute is somewhat "more curly" (shallower slope} than a drill, almost like a wood augur. I would have to look at the brand.

The ones I tried to use were 1/4-20. Shattered one, it just stopped cutting, apparently expanded and jammed in the hole. FAR weaker and less useful than the "Spiral point" type, which is what I use. Do not think I have ever broken a spiral point tap by hand.

At least it was fairly easy to get the pieces out, as I recall.

pinstripe
08-08-2017, 02:03 PM
Nice build & video Justin.

Don't give up on the spiral flute taps, they are nice on blind holes. I'd never used one until I heard Max or Justin talking about them on the podcast. Picked up a few on eBay, and glad I did. They do look weak by comparison, but the cutting forces are so low that I haven't had one feel like it was going to break yet.

Speaking of the podcast... :)

lugnut
08-08-2017, 03:59 PM
Great build and video. I always like to watch videos like yours because I learn from the techniques used. I have a few smaller spiral flute taps and mostly use them in aluminum, because they seem to clean out the chips better.
Thanks for sharing your build.