CAM newbee: How to drive a 4th axis using F360?

[thburn]

Hello,

I am brand new to CAM inside F360. Up to now I worked 'only' with modelling workspace for 3D printing.
Now I ordered a Stepcraft 2/600. Further I ordered the UCCNC Software and also the 4th axis module.

https://www.stepcraft-systems.com/cnc-3d-systeme/stepcraft-2-600

To make good use of the time until the machine is delivered I have following question:

Beneath 'normal' milling operations I want to create my custom addon for this machine which is a 'paste extruder' (first for wood glue only).

My idea is to use a 'normal' syringe and add a stepper motor and a spindle to it to empty the syringe.

Now my question is how can I use F360 CAM module/workspace to drive the syringe?
Lets say I want to put the wood glue in a shape of a circle onto a piece of wood.

How I use F360 to create the circle? In my understanding I need only the path (the circle) which the syringe has to follow.

Do I use the drawing functions to create this paths? Or do I have to create a 3D object of the circle?

I also don't know how to tell F360 how to drive the syringe to squeeze out the wood glue under a certain speed.

Further I must lift up the syringe after the circle is done, move to the next shape and push the syringe down again.

Any help to come closer to my target is highly appreciated!

Thanks a lot!

[Steinwerks]

There is no 4th axis continuous toolpath yet, but soon if you'll be using Fusion 360 Ultimate. That said, programming an A-axis move is pretty simple in and of itself but it depends on how the machine commands the movements (inverse time or degrees per minute).

Your best bet is to provide a model example that we can help with to get a clearer understanding of what you're trying to accomplish.

As to actuation of the syringe, well that's going to be a completely custom solution.

[thburn]

@Steinwerks:

thanks for reply. To make it more clear what I want to get I attached an image to this message.

For the 4th axis I think I don't need a toolpath because I just need the stepper motor turn with a certain speed to squish the wood glue out of the syringe.

Of course I need also to start and stop the stepper motor at the starting / ending points of the shape I want to follow (in the image I used a circular shape as example).

- Can I generate the G-Code for this with F360 now?

- If I cannot create the G-Code for the 4th axis with current version of F360 may it is possible to use F360 to generate the G-Code to move the tip of the syringe along the circle? And the 4th axis G-code I can then add manually using a G-code editor?

Thanks... 

[Steinwerks]

Moving the tip around the circle would be very simple and can be generated now. Actuating the plunger will be more of an experiment in terms of automation. I think you could do it with a little tweaking of a post to output a spindle speed to set the plunger feed (it is an RPM after all) but the machine side is going to be completely custom as far as I know. Definitely possible.

[thburn]

@Steinwerks:

thanks again for reply, but sorry I did not really get what you wrote - remember I am newbee to CAM 😉 - may you can explain it again?

You said:
Moving the tip around the circle would be very simple and can be generated now.

How do I do this? Do I use an SVG file and create a toolpath from it?

You said:

Actuating the plunger will be more of an experiment in terms of automation. I think you could do it with a little tweaking of a post to output a spindle speed to set the plunger feed (it is an RPM after all)
What is 'tweaking of a post'? Does that mean what I suggested to edit the C-Gode manually? If yes what will be the G-code commands I have to enter?

What means '(it is an RPM after all)'?

Thanks in advance for making it more clear to me 😉

[thburn]

Hi,

may someone else can help here?

Thanks a lot...

[Steinwerks]

Have you gone through the CAM introduction series that Mike Mattera made? They are linked in my signature as well as stickied at the top of the forum.

As far as driving the 4th axis to push a plunger, this is a mechanically custom configuration that is going to be a bit above the nominal level of help available on this forum. It's unrelated to Fusion generally, you would have the same challenges no matter the software used. Using a 4th axis to do so may actually be more complex than other options as well, and I suggest seeking out automation help before worrying about how it will be programmed.

[porsbym]

Seconding what @Steinwerks said, I can add a little bit of specifics for the StepCraft/UCCNC combination since I happen to be familiar with that combination (that's what I use).

On the CAM side:

Create any toolpath operation (probably 2D Contour will cover most of your needs). Use a flat end mill with the approx diameter of your glue strips. You probably want to turn off all linking and transition moves. Think of the cutting passes (shown in blue) as the passes that will get glued.

On the post/G-code side:

You may need to customize the stock UCCNC post to turn on and off the spindle when the movement is NOT a cutting move.

In UCCNC:

I don't think you need to do anything here. But if you do need something extra e.g. when turning on/off the glue "gun" you can customize the spindle on/off macros.

On the hardware side:

You will need a little bit of electronics between the spindle controlling pins from the output connector on the Stepcraft and the Stepper motor. An Arduino and a Stepper driver should get you quite far.

Best of luck! Please post some pictures of your results!

/Mark

[thburn]

@Steinwerks, @porsbym,

thanks for reply again, this is reall helpful for a newbee like me.

Regarding the hardware I will use my 3D printer plus DryLin components from igus to create it, so this seems not to be a big problem.

@porsbym: You wrote:

You will need a little bit of electronics between the spindle controlling pins from the output connector on the Stepcraft and the Stepper motor. An Arduino and a Stepper driver should get you quite far.

Are you sure that I need a stepper driver? The reason why I ask is I yesterday called Stepcraft in Germany regarding this issue and they told me I can DIRECTLY connect a stepper motor to the D-Sub output connector of Stepcraft 600 - there is no need for a driver - I am a littlebit confused now?!?

I looked on their website and they offer a 4th axis tool called: circular table with three jaw chuck:

https://www.stepcraft-systems.com/en/accessories/system-accessories/cnc-accessories/circular-table-w...

On the images one can see that the stepper motor is directly connected to the D-Sub plug - no driver electronics in between - so I think they are right a driver is not necessary.

What do you think?

@porsbym: You wrote:

On the post/G-code side:

You may need to customize the stock UCCNC post to turn on and off the spindle when the movement is NOT a cutting move.

Does that mean I have to add the GCodes for the 4th Axis manually?

New question:

On the download side for UCCNC post processor I can read:
if you are using a fourth axis, make sure to enable either the property 'fourthAxisAroundX' or 'fourthAxisAroundY'. 

What does fourthAxisAroundX and/or fourthAxisAroundY mean and what I have to enable for my syringe?

Thanks again...

[porsbym]

I suppose that is possible if you don't also need the 4th axis attachment at the same time. I guess I got side tracked by thinking you wanted 4-axis machining also

What the post does with regards to 4-axis is NOT what you need, though. It is for controlling the angle that it moves to coordinate positioning of the tool in relation to the toolpath calculated in CAM.

I think you can do one of two things:

1. Find a way in UCCNC to turn on/off continuous rotation of the step motor based on the spindle start/stop commands.

2. Implement a custom post to calculate a "fake distance" in the post to drive the A axis an appropriate number of turns to give you the expected glue output for a given movement distance.

There are probably other options also. I guess which one is best for you depends on what area you are most comfortable with: Electronics, UCCNC customization or post customization.

/Mark