[X2cnc]

So far I've seen two automatic tool changers for the X2:

A) The Z-Bot changer, as sold by littlemachineshop.com

B) Dan's hossmachine changer


The Z-Bot mounts to the left side of the table. No tools overhang the table, but it has to have enough space over the workpiece to swing the longest tool into position under the spindle. The tools are mounted in E-clips mounted on a chain drive. The headstock positions itself to the correct Z height for the E-clips to match the slots in the toolholders, and then the table scoots over to snap the E-clip onto the tool. The headstock then rises up off the toolholder and the chain indexes around to the next desired tool.

The Z-Bot is very expensive, but after looking at the manuals on the littlemachineshop.com site, it does a whole lot - there's a whole separate QC controller, a power drawbar is included, Mach3 screens included, and a whole array of interlocks and safety devices. It appears to be a well-engineered system, but $1500 is completely out of my price range.

Dan's hossmachine changer is much simpler. Tools sit in a rack on the left side of the table, occupying part of the table's travel area. The table simply positions itself under the headstock, which then runs up and down to grab the toolholders. You have to provide a power drawbar to operate it; any power drawbar will work; Dan provides plans for those, too. You can build Dan's design for peanuts, but the more rows of tools you mount, the more X workspace you lose. Dan gets around that with his "X2 Freak" mod to increase table travel.


I lust for an ATC, but the Z-Bot isn't in my price range. I could build Dan's design easily enough, but I don't want to lose the table space (or go down the X2 Freak trail; I'd like to get this thing finished someday!).

Over the weekend I've been sketching another method. Basically, it's a carrousel (like one of those rotary CD changer tables) mounted on swinging arm attached to the side of the column. It would require a stepper to rotate the table and an air cylinder to move it from "park" to under the spindle.

Operation:
1) ATC mode runs headstock to top of column
2) air cylinder swings tool carrousel under spindle (indexed to an empty space)
3) power drawbar opens, dropping tool into counterbored slot in carrousel
4) stepper indexes tool carrousel so correct tool is in position
5) headstock lowers onto tool. (The swinging arm holding the carrousel has some compliance via a spring in the hinge)
6) drawbar closes
7) headstock lifts tool out of pocket in carrousel
8) air cylinder swings tool carrousel back to park position

This all assumes the carrousel is counterbored to hold the toolholders and slotted so the tools can be removed after being lifted enough to clear the counterbore. You could use big E-clips if you can figure out how to make them.

It's a lot simpler than it sounds; it's just a swinging tray that spins to present the right tool to the spindle.

Pros:
All toolchanges occur near maximum Z. You don't have to move the table unless a tool would hit the workpiece.

No loss of table workspace.

Tools stored high and off to the side would collect fewer chips that might cause trouble.

Cons:
Requires a stepper output and a relay output for the air cylinder.

Tools not positively retained; they could dance around if the column vibrates.

[hoss2006]

Soon there will be 3.
Already a work in progress my friend,
shouldn't be too much longer.
Hoss 16 Tool Automatic Tool Changer
Would have had it completed if the console didn't take so long.
I have the software and electronics done, just need to finish milling the metal bits.
All the hardware is on hand.
It won't just be for the X2 though,
any mill with power drawbar and 3/4 in. tool holding capabilities will do. :wave:

[philbur]

The extra USD 1,500 for an all bells and whistles tool-changer would buy an x3 or x4 with the extra table space/travel to accommodate the fixed tool changer. So no loss of table space and better machine into the bargain.

Something to think about at least.

Phil

I could build Dan's design easily enough, but I don't want to lose the table space

[The Blight]

Phil he also said that it was way out of his price range. He is thinking about making one.

X2cnc take a look at this link. I know it's not for the X2, but I have been drawing up one of these for my X2. You can sort of figure out how it works by just looking at some of the pictures. http://home.insightbb.com/~joevicar3...nger_Plans.htm

[fretsman]

How does one set up an air cylinder like that? What exactly would be needed to trigger it?

Thanks,
Dave

[praetor]

...from homeshopaccessories.com, there's also an ATC yahoo group for further ideas:

http://groups.yahoo.com/group/minitoolchanger/

[philbur]

Yes but it is still "something to think about at least".

A person might not be able to justify 1500 for a toolchanger on an X2 but a person might be able to justify 1500 for a more capable machine plus a tool changer.

Phil

Phil he also said that it was way out of his price range. He is thinking about making one.

[Mike Nash]

Just as side note, you might want to consider a Geneva drive for the indexer. It might be easier, stronger or some other handy adjective than a straight stepper. Certainly it could be cheaper to drive with a small gear motor and limit switch for position detection.

http://en.wikipedia.org/wiki/Geneva_mechanism

[The Blight]

but $1500 is completely out of my price range

He has the X2, and wants to make an ATC for it. Clearly he wants to save some money too. If he wanted a new machine he would have said so (and I bet he knows about the other machines). If he had $1500 just lying around, he would probably buy a bigger machine, but he would still want the ATC. Getting an ATC for the bigger machine costs just as much.

So to keep on topic. Triggering the air cylinder (or cylinders) needs some kind of logical control unit to function. I would also add some kind of sensor to the system to check where the cylinders are at. You could probably let the computer do the controlling if you have some suitable outputs. In my design I have switched out the cylinder moving the head with a stepping motor and a threaded rod. You could also switch out the drawbar cylinder with a stepping motor too, but you would probably need some sort of gearing to get enough torque to compress the springs. If you use stepping motors for both tasks then you could use a micro controller to take care of signal handeling (that is if you know how to program one or know someone who can).

This is in no way an easy design, but it does look kind of cool, and it doesn't get in the way.

Also like praetor pointed out. The yahoo group has lots of pictures and information on it too.

[X2cnc]

http://home.insightbb.com/~joevicar3...nger_Plans.htm

I'll be danged if I can figure out how that thing works; from the pictures, the geometry looks like it's trying to cram the toolholders into the spindle at an angle.

[X2cnc]

Y
A person might not be able to justify 1500 for a toolchanger on an X2 but a person might be able to justify 1500 for a more capable machine plus a tool changer.
Phil

I have a Gorton 9J out in the shop. It's plenty capable. However, it's 102F out in the shop, and it's 81 in here in the computer room where the X2 is...

[philbur]

Sorry for suggested an alternative way of looking at the issue.(chair)

You did of course miss my point in you hurry to chastise me. Yes the larger machine still needs the ATC but the whole point was that you can sacrifice some of the additional space to accommodate a simple static tool changer.

Phil

PS: My suggestion may not be of interest to x2cnc but it might give others with similar goals something to think about.

He has the X2, and wants to make an ATC for it. Clearly he wants to save some money too. If he wanted a new machine he would have said so (and I bet he knows about the other machines). If he had $1500 just lying around, he would probably buy a bigger machine, but he would still want the ATC. Getting an ATC for the bigger machine costs just as much.

[philbur]

There is a forum for this toolchanger on Yahoo.

http://groups.yahoo.com/group/minitoolchanger/

There is a movie of it in operation in the files section.

Phil

I'll be danged if I can figure out how that thing works; from the pictures, the geometry looks like it's trying to cram the toolholders into the spindle at an angle.

[X2cnc]

You did of course miss my point in you hurry to chastise me.

I wasn't chastising you. The wonder of electronic communication is that we can talk nearly instantly to anyone; the downside is that sometimes the feeblebrotzes get snarpfurbled.

[The Blight]

X2cnc, he was talking about me.

Why post such a thing in this topic? He is asking about an ATC for his X2 and I'm sure he knows all about the bigger machines. People looking for bigger machines will not go into a topic about ATCs looking for machine recommendations.

And even if he got a bigger machine, he would still have to pay a lot of money for an ATC. I have not yet seen any ATCs for the X3 or X4, so he would have to think up one on his own. Just a lot more work and money.

It would have been a good point if he was planning on spending such a large amount of money on an ATC, but here seems kind of pointless. It might help some of those other people watching this topic, but my bet is that they came here to look for some cool ATC designs. I would say that X2cnc seems like a smart enough guy that he can figure out what is more economical on his own.

X2cnc if you want to, I could send you some pictures of my design. If you have solidworks, I could even send you the cad files.

[X2cnc]

X2cnc if you want to, I could send you some pictures of my design. If you have solidworks, I could even send you the cad files.

I don't have Solidworks, but I'd love to see some pictures of your design.

I'm sure the swinging-carrousel design I came up with would work, but I started this thread hoping someone would suggest a different, perhaps better, idea.

[Crevice Reamer]

I'm just noodling here, but how about a straight rack that mounts to the table side (or end) and slides or pivots on and off? Nothing to turn with a stepper. Nothing to index. Either an air cylinder or a gearmotor could simply drive it onto the table or back to park.

When not needed, the table space is available. Once shifted into place, it would work just like Hoss's passive rack.

CR.

[philbur]

I think the problem is that you can't use the space on the table for a part if the tool rack needs to move into that space for a tool change, so you may just as well leave it permanently bolted to the table. It would work if the rack were up at maximum Z, operating above the work piece, but then if your Z is slow tool changes could be like watching grass grow.

Phil

I'm just noodling here, but how about a straight rack that mounts to the table side and slides or pivots on and off? Nothing to turn with a stepper. Nothing to index. Either an air cylinder or a gearmotor could simply drive it onto the table or back to park.

When not needed, the table space is available. Once shifted into place, it would work just like Hoss's passive rack.

CR.

[Crevice Reamer]

I think of the space as mainly used for work clearance. I doubt if many folks would be bolting a vise to the table end. I'm envisioning some rails bolted to the sides of the table, and a simple rack that slides onto or off of the table space at the end.

CR.

[digits]

I think the problem is that you can't use the space on the table for a part if the tool rack needs to move into that space for a tool change, so you may just as well leave it permanently bolted to the table. It would work if the rack were up at maximum Z, operating above the work piece, but then if your Z is slow tool changes could be like watching grass grow.

Phil

Does tool change speed matter at all on an X-2? It's not as though your cycle times are going to be measured in seconds - I would have thought that reliability is the key here...