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Ross77
31-10-2017, 09:37 PM
Im looking for the best option for an ATC from my CNC lathe, its basically a Myford ml10 with just the tee slot table.

Struggling to find any for sale and seen a few plans with two different designs for the holding mech. Some use a ratchet and pawl rotating in one direction and others have a toothed ring and have to push the plate forward to rotate to the next position.

Which option is best?

Lastly any plans for a suitable one? Cheers

Chaz
01-11-2017, 09:27 AM
There are some on GrabCAD worth looking at.

Effectively you have 4 options.

Manual stuff like Multigrip / Dickson holders.
Gang Tooling, might be worth a look pending what type of stuff you turn.
Turret - rachet / pawl
Turret - pnuematic (or similar) locator function

There is a guy on ebay making very decent looking turrets - sells them for around 500 ish. The only reason I havent bought is that they do max 10mm tools and Id like larger for my lathe.

https://www.ebay.co.uk/itm/Diy-cnc-lathe-turret-see-new-photos-https-youtu-be-cCDulVashA/302505482016?hash=item466ebb5720:g:6IwAAOSwK~RZ-JvI

Not seen him list them like this (in kit form) before.

Spoken to him extensively on whatsup, does this for day job too, seems to know his stuff, worth a look. He also has a gang tool setup for sale but might be too big for a Myford.

magicniner
01-11-2017, 12:59 PM
There is a guy on ebay making very decent looking turrets - sells them for around 500 ish. The only reason I havent bought is that they do max 10mm tools and Id like larger for my lathe.

https://www.ebay.co.uk/itm/Diy-cnc-lathe-turret-see-new-photos-https-youtu-be-cCDulVashA/302505482016?hash=item466ebb5720:g:6IwAAOSwK~RZ-JvI

Not seen him list them like this (in kit form) before.

Spoken to him extensively on whatsup, does this for day job too, seems to know his stuff, worth a look. He also has a gang tool setup for sale but might be too big for a Myford.


The turning tool holders look easy to make in a larger size?

Chaz
01-11-2017, 05:14 PM
The turning tool holders look easy to make in a larger size?

Perhaps. Ive not seen the kit broken down like this before. It might be where the 'centreline' is effectively which is more challenging.

magicniner
01-11-2017, 05:56 PM
Perhaps. Ive not seen the kit broken down like this before. It might be where the 'centreline' is effectively which is more challenging.

Given that they mount in the same holes as drilling and boring tool mounting holes then the centre line is the mounting hole centre line, no challenge! ;-)

Chaz
01-11-2017, 06:01 PM
Given that they mount in the same holes as drilling and boring tool mounting holes then the centre line is the mounting hole centre line, no challenge! ;-)

True. Spoken to him, he will likely be able to mod these to go to 12mm. I can then probably make my own later if I want to go to 16 or 20mm tooling.

magicniner
01-11-2017, 06:04 PM
Bonus! :D

Ross77
01-11-2017, 08:48 PM
I did see that one but put off by the small tool capacity. May have to message him if it can hold 12mm

I'm currently using 16mm tooling with a large QCTP and getting a nice Finnish so don't want to go down to much in case the finish quality is reduced.

would also need to buy all new tooling

Chaz
01-11-2017, 08:58 PM
He can mod to 12mm. Anything larger needs new holders done.

Ross77
01-11-2017, 09:34 PM
Just messaged him so find out soon enough.

looking at the pictures again it does only have 1 pawl on the ratchet so that might limit the force it can take

magicniner
02-11-2017, 09:14 AM
would also need to buy all new tooling

I use tooling from 6mm through to 25mm+ shank on my Myford Super 7, by milling a relief pocket on the holder side of the shank which just accommodates the bottom lip of the Myford size QCTP holders the ability to use the tool in a larger holder isn't compromised, rigidity isn't reduced to any significant degree and centre height isn't an issue :D

Chaz
02-11-2017, 09:20 AM
Is there a view on what size tool is required? For my Harrison M300, this is a semi beefy home lathe. 12mm almost looks too small. I spoke to Kenny last night (dude selling the stuff) and he says on his Haas CNC lathe, he tried bigger tools (20mm etc) and found that they took up too much space and settled with 16mm. Suppose feeds and speeds are important here too. Most of my turning is alu or softer steels.

m_c
02-11-2017, 05:02 PM
Is there enough height on a ML10 for that style tool changer?

Ross77
02-11-2017, 11:27 PM
Is there enough height on a ML10 for that style tool changer?

Umm No. just checked tonight and it is only 50mm from the table to the center of the spindle.

Looks like it will have to be custom made if I go down that route. maybe try gang tooling first.

m_c
03-11-2017, 04:18 PM
I used a mix of quick change holders, and a gang tooling block when I had my Conect lathe.

A couple photos can be found in this album over on flickr - https://www.flickr.com/photos/mc_mtb/albums/72157625154378941

IIRC they were ER25 holders.

Chaz
06-08-2018, 02:47 PM
Ive actually bought one of these so if anyone needs info, let me know.

Ross77
09-08-2018, 08:36 PM
How are getting on with the ATC? is the turned finish similar to a QCTP

Im looking at building one but cant decide on this type with the ratchet and pawl or the pneumatic ones with the toothed register. Seems to be pros and cons to both

Chaz
09-08-2018, 08:41 PM
How are getting on with the ATC? is the turned finish similar to a QCTP

Im looking at building one but cant decide on this type with the ratchet and pawl or the pneumatic ones with the toothed register. Seems to be pros and cons to both

I think its decent. I struggled with parting, he uses an alu 'pawl' which ive since machined out of steel, havent tested it yet. For a smaller machine, its ok but it struggles a bit with the heavier stuff.

Ross77
09-08-2018, 08:57 PM
Thats for the heads up. what size is the main block?

My friend has the little denford one and said it suffers from similar issues. We were looking to make one with the pnuematic actuator but seem like a lot of work to me.

I just seen this one http://lukesprojects.weebly.com/automatic-lathe-tool-changer.html it uses two adjustable pawls and looks quite substantial

Do you know if the pneumatic ones are the best option? either way it will be an investment so we want to make the best possible version

Chaz
09-08-2018, 09:01 PM
Thats for the heads up. what size is the main block?

My friend has the little denford one and said it suffers from similar issues. We were looking to make one with the pnuematic actuator but seem like a lot of work to me.

I just seen this one http://lukesprojects.weebly.com/automatic-lathe-tool-changer.html it uses two adjustable pawls and looks quite substantial

Do you know if the pneumatic ones are the best option? either way it will be an investment so we want to make the best possible version

Sorry, main block? The mounting block? Probably around 100 x 100 mm but can check over teh weekend.

m_c
09-08-2018, 10:46 PM
Pneumatic turrets using a hirth or curvic coupling are far sturdier, but as you're aware, they are far more complex (and good hirth/curvic couplings are not cheap!).
They have the benefit that the tool disc gets clamped firmly in place with lots of mating surfaces, whereas on a ratchet and pawl setup, not only do you have flex due to the shaft needing to be able to rotate, you're relying on a single point of contact to resist cutting forces.

And as already mentioned, parting is where you're most likely to notice any play/flex on a lathe.