Hi guys,
I was just wondering if it is possible to have a multiple bit CNC router? Not sure why I would want multiple bit though, just wondering. I would think that a lot of it has to do with software, for knowing the coordinates for the bits, and then some hardware for actually setting the bit in place and tightening.
Thanks. :D :D :D :D :D :rainfro:

I am using a Sears Quickrout. Pictures on last page of this thread:
http://cnczone.com/forums/showthread.php?s=&threadid=694&perpage=15&pagenumber=4

Turbocnc allows setting each tool.

Bill

I am using a different approach. I have 3 routers mounted on my machine, each one with its own bit.

http://www.cnczone.com/forums/showthread.php?s=&threadid=2580

That sure is cool, but how does it work? How can the software control the three routers? I saw that you are using nomal TurboCNC.
Thanks.

The easiest way is for each router to have it's own axis to be able to move up and down independently, but it's more complicated to build. Buscht's looks like they all move together. Not sure how he does it, because it seems like the other bits would get in the way. With independent axis', you just move each one independently. You would probably use fixture offsets to locate the second (and/or third) router(s). Sorry, but I don't know the g-codes offhand.

Personally, although I haven't tried them yet, I'd go with the Craftsman collets like Bill. Get a good Porter-Cable Router, and set up all your bits in the Craftsman collets, and tool changes can be very quick. But, if you need unattended tool changes, dual routers would be the way to go. (If you have the room for them)

Originally posted by Sanghera
How can the software control the three routers? I saw that you are using nomal TurboCNC.
Thanks.

The first router could be your "Z" axis, the second one could be your "W" axis. To use the first router you'd use

G1 X1 Y1 Z-.5

the second one would be

G1 X1 Y1 W-.5

You'd probably have to manually edit the code to switch, depending on what you'd use to generate the g-code.

Ok, Thank you very much for the reply. :):):):):):):rainfro:

You Could do what im doing if you can get access to a cnc lathe im making a belt driven spindle with a 30 taper to accept regular cnc machining tool holders just program an op stop and drive her to home bout 30 second tool change and you are back in to the wood

Sounds like a good idea. Now, how does it work. Is this right. So, there is a spindle with a 30 degree taper driven by a belt, and the machine chuck comes near it and eubs against it to loosen the chuck, goes and get the right bit and then tightens. I'm probably thinking too complicated. :) :rainfro:
Thanks.

Also, how can you program your software, so that it can change bits when you want it to. How do you tell it where "home" is? Probably a whole lot of stuff to do with G-Code.
Thanks.

Hello?

Sorry, I missed this thread. On my router all 3 heads move up and down at once. They are 7" apart, so the widest part I can make is 7" without the router bits hitting. That is the drawback to my system.
On the plus side it is very simple and cheap.

Right now I don't have automatic on and off controls for the routers. There is a fixture offset command in G code, G92 I think, that let's you reset the program origin. Just move the origin 7" between cuts and everything works fine.

I change tools all the time when I do a 3D wood carving job. You can see my machine at the post below.


http://cnczone.com/forums/showthread.php?s=&threadid=171

The custom collets start on page 4 of the post.

Thanks for the post and for all of the replies. So does your (HomeCNC) system change parts as it is needed for the part, or do you have to manually change the bit? I mean, have you set something up so that the bit can be changed in the middle of making a part? I'm not sure what the G-Code would look like or what I would have to do to program the router to know where the bit is that it needs and change, I have an idea about the hardware, but I'm not sure about the software.
Thank you very mcuh. :):):):):):):rainfro:

Typically Sanghera you would use the "M" code "M0" this code would be placed at the end of a milling cycle where you need to change a tool, it stops the program, the spindle, coolant if applicable, giving you time to manually change the tool, then you push "Cycle Start" to continue on.

Ken

How would you program it so that it can do an automatic change for the bit you want?
Thanks.

You will need a automatic tool changer ("ATC") for that. Normally found only on commercial machines. When ever the program encounters the code Txx it knows to get that tool.

Ken

an automatic toolchanger would be a SWEET DIY project for the group. those sears parts could be the basis... i havent much clue how it would work though - i could donate PIC programming though to control it.

would be a SWEET DIY project
I agree it would, I think the equipment would have to be designed from the get-go with this in mind as most of the DIY routers/mills do not have enough Z height to provide the necessary room for the tool change. Possibly if they could go full back and the tool changer came up from the bottom ?????

I would love to seee someone come up with that.

Ken

So, you guys want to get together and make something like that? I could maybe help. How do the industrial machines change bits? What mechanism?
Thanks.

Sanghera that seems like a neat idea but every machine is different, making it impossible to develop a universal "ATC". Owning a machine that has a ATC I know enough to say it will get complicated real quick for the DIY'r. The spindle has to have a means of accepting a tool automatically, the controler has to know at all times what tool is in the spindle and where the next tool is in the pallet, it has to be smart enough to put it back in the same slot from which it came, and a ton of other mechanical considerations. Not a easy task at all.

EDIT:
It could be possible to set the tool pallet up with sequential tools as needed for any given job. Unless this would be for production, I think it would be nothing more then a extremely cool
setup and require far more expense and effort then it would be worth.


Ken

I have seen a plotter at a high school that had about seven differenct "pens" that it can pick up, all different colours or whatever. It plots CAD drawings, and just picks up pens as it needs, it is very neat to watch. I know that the CNC would probably be a little bit more complicated.
Thanks.

Here are plans for a DIY toolchanger. It looks very neat and could probably be adapted.
http://home.insightbb.com/~joevicar3/default.htm

Yeah, these plans could be a good starting point for modification ideas to other routers/mills. I purchased them months ago just because they looked interesting.
Ken

The easiest way to build this is to copy the concept found on the heavy duty woodworking equipement.

The kind of machine that i repair have 8 motor mounted on a rotating plate. The tool hare permanently mounted with a collet on each motor, each time you call a tool change, the plate rotate to point to good motor. It's like a revolver. I think of using this principe on my second machine, using 2 or maybe 4 porter cable router mounted on an aluminium plate rotating with a gearbox with an encoder mounted on it. You only have to program some macros with mach2 an wire home switch on the plate and youre done!! Not easy as talking of it but i think it's the most easy to build. I prefer to work on electronics than complex mechanics.

I have attached a picture of the machine i'm talking about.

An M06 is the tool change code. I change it manually. It is difficult to make an auto tool changer when your using a standard router like a Porter Cable. There is not through the spindle hole to use a draw bar on.

With the revolver, you not change the tool, but the complete motor, no drawbar needed!!

Is this something of interest?
http://groups.yahoo.com/group/minitoolchanger
http://www.homeshopaccessories.com/