Acorn Controller and Foam cutting

[JoNo]

Hello to all,
Has anyone managed to use the Acorn controller to control a 4 axis hot wire foam cutter?

regards
joe

[martyscncgarage]

Hello to all,
Has anyone managed to use the Acorn controller to control a 4 axis hot wire foam cutter?

regards
joe

Need more info about the machine, but should be no issue. I say that because I have a customer that has one and we have planned the upgrade, but he has not pulled the trigger as of yet. Quite a large machine.

You just need to know what M code turns the hot wire control on and off.
We had planned to use AC servos

Marty

[JoNo]

My machine is shop-built using Hi-Win slides, ball screws and steppers, with the hot wire held in a large bow so that tapers, cones, etc can be cut, ie, true 4 axis control - each axis moving totally independently. The hot wire is 2meters long, and I use this to cut aircraft wings, with MACH3. I need to upgrade since it is becoming more difficult to maintain the XP PC these days, and am reluctant to stick with MACH4 as it is a little antiquated these days.
The Centroid PC software manuals, etc, do not mention foam cutting anywhere, and the function is quite different from 4 (or more) axis Mill operation.
I have not found any users or examples of the Acorn used for a true 4 axis foam cutter, so I am still not sure this is possible.

[martyscncgarage]

My machine is shop-built using Hi-Win slides, ball screws and steppers, with the hot wire held in a large bow so that tapers, cones, etc can be cut, ie, true 4 axis control - each axis moving totally independently. The hot wire is 2meters long, and I use this to cut aircraft wings, with MACH3. I need to upgrade since it is becoming more difficult to maintain the XP PC these days, and am reluctant to stick with MACH4 as it is a little antiquated these days.
The Centroid PC software manuals, etc, do not mention foam cutting anywhere, and the function is quite different from 4 (or more) axis Mill operation.
I have not found any users or examples of the Acorn used for a true 4 axis foam cutter, so I am still not sure this is possible.

Can you demonstrate your machine cutting with the 4th axis on a video and supply a gcode program?
If Mach can do it, I can't see why Acorn can not.

[JoNo]

Not enough space around the machine to get some distance for the video cam to see both gantries moving independently...Next best option is a utube video which gives the idea - Credit to the Utuber - not my machine



If you look at the utube video - the wing is tapered ,ie, the one end is thinner and narrower than the other end. So the hot wire has to cut a smaller section at one end than the other, and so the gantries must move at different speeds and positions at each end -
Take a look at 30seconds - the gantry closest to the viewer moves faster into the foam, compared to the gantry away from the viewer.
@ 3.10m the wing is almost done, and the gantry furthest moves more slowly as the wire is about to exit the foam.
It is complex to describe but the action is quite simple..I am sure the Acorn can drive the steppers and gantries with no problem, but it needs o be told how - the software in the PC needs to be able to interpret the (4 axis) Gcode as required for a foam cutter, as opposed to , say, for a 4 axis mill - the Centroid software makes no mention as far as I can find of being able to set this up and to be able to visualize the cutting path.

You asked for a sample Gcode file - This is for a tapered wing section.

[cnckeith]

yes, no problem... Acorn with Pro License is a true 4 axis simultaneous CNC control, the g code program and cnc12 can simply control each axis independently. x,y,a and b. no sweat. easy peasy.

[JoNo]

Sorry to harp on this, but...

I tried installing the CNC12 software to see if this can drive a Foam Cutter. Firstly there does not seem to be a demo mode or a mode where the software can run so that one can see the features, etc. When run it sits waiting for a connection to the Acorn..
Secondly, during the install, it allows ONLY lathe or mill installation - NEITHER of these will control a 4 axis foam cutter as the geometry is quite different.

Between Hardware and Software, there is a lot of money to pay, and I cannot find a definitive sample or example of this actually being possible.

I have asked the question as well on the Centroid on-line Information Request page, but they simply do not answer...

Very difficult to purchase this product under these terms!

[martyscncgarage]

Sorry to harp on this, but...

I tried installing the CNC12 software to see if this can drive a Foam Cutter. Firstly there does not seem to be a demo mode or a mode where the software can run so that one can see the features, etc. When run it sits waiting for a connection to the Acorn..
Secondly, during the install, it allows ONLY lathe or mill installation - NEITHER of these will control a 4 axis foam cutter as the geometry is quite different.

Between Hardware and Software, there is a lot of money to pay, and I cannot find a definitive sample or example of this actually being possible.

I have asked the question as well on the Centroid on-line Information Request page, but they simply do not answer...

Very difficult to purchase this product under these terms!

No problem.
It doesn't get much better than getting a response from Keith.
All I can tell you if Mach can do it, CNC12 can do it. (No demo version of the software)
Really not sure what your concerns are. Centroid CNC12 does full simultaneous 4 axis motion if you by the Pro License.
All the features are listed here: about half way down the page

Marty

[martyscncgarage]

Looking at your G code,
I assume your X & Y axis are linear, are your A & B axis both rotary?
The video shows two linear axis moving....

Marty

[cncsnw]

Generally, you want to use "Mill" software for anything that is not a lathe or cylindrical grinder.

There are a thousand specialty applications. Centroid does not have a "hot wire foam cutter" version of their control, any more than they have a "waterjet" version or a "laser table" version or a "pick and place robot" version. But if the application basically just requires telling up to four motors where to go, and how fast, then you can do it with the mill software.

The burden of deciding where to move the four axes, and how fast, in order to cut the part you want to cut, is on you and on your CAD/CAM software. The control is not going to automatically figure out how to command the A and B axes based on the commanded movements of the X and Y axes. However, the sample program you posted suggests that you have that sorted out already for the Mach3 control.

You will probably want to use "inverse time" feedrate control (G93), so that your CAM software can simply calculate how long each move should take to complete. That avoids the otherwise complicated question of which end of the wire should be moving at the programmed inches per minute, and what contribution axes #3 and #4 make to overall speed.