Nozzle wipe?

blt3dp

I'm curious about this myself, I was thinking of drawing up a hollow cylinder with no tops and bottoms and the wall thickness as thick as what I have my nozzle set to in my slicer. Doing no skirt or brim. I was going to slice it and see what gcode it output. Probably a bunch of segments. I bet I could choose however many to make an arc the length I wanted.

NitroFreak

You could use a G2/G3 arc move with the center at X/Y 0 and a radius of the bed diameter/2.

blt3dp

I couldn't get G2/G3 to work.

Let's start with what a Delta thinks is clockwise vs counter clockwise.
What does it, consider what lets say when looking down at the print bed from the top

We know 0,0 is in the center
-X is to the left, +X is to the right
-Y is to the front, +Y is to the back

My assumption is that for clockwise, it would go: back right quadrant, front right quadrant, front left quadrant, back left quadrant.

But I couldn't get a movement with G2 for clockwise, G2 for counter-clockwise did move from right to left along the front of the bed.

But I kept getting that the movement was out of the printers print area

Running on a Delta with a 284 mm printable area.

So in a CAD drawing, I drew a circle smaller than the printable diameter of my bed. I drew a line from center to the circumference of the circle. I mirrored it and then measured their distances from the origin in X and Y.

Moved to the first position,
G1 X-15 Y-139.79 F1800

Tried to move to the opposite side along an arc,
G3 X15 Y-139.79 I0 J-140.59248 F1800
It kept giving missing I or J parameter

I tried G3 X15 Y-139.79 R140.59248 F1800 and got missing
It kept giving missing I or J parameter

Then I tried
G3 X15 Y-139.79 I0 J140.59248 R140.59248 F1800
It moved, but didn't appear to complete the arc, position in X was something like 1.6

Mysta

@blt3dp said in Nozzle wipe?:

I couldn't get G2/G3 to work.

Let's start with what a Delta thinks is clockwise vs counter clockwise.
What does it, consider what lets say when looking down at the print bed from the top

We know 0,0 is in the center
-X is to the left, +X is to the right
-Y is to the front, +Y is to the back

My assumption is that for clockwise, it would go: back right quadrant, front right quadrant, front left quadrant, back left quadrant.

But I couldn't get a movement with G2 for clockwise, G2 for counter-clockwise did move from right to left along the front of the bed.

But I kept getting that the movement was out of the printers print area

Running on a Delta with a 284 mm printable area.

So in a CAD drawing, I drew a circle smaller than the printable diameter of my bed. I drew a line from center to the circumference of the circle. I mirrored it and then measured their distances from the origin in X and Y.

Moved to the first position,
G1 X-15 Y-139.79 F1800

Tried to move to the opposite side along an arc,
G3 X15 Y-139.79 I0 J-140.59248 F1800
It kept giving missing I or J parameter

I tried G3 X15 Y-139.79 R140.59248 F1800 and got missing
It kept giving missing I or J parameter

Then I tried
G3 X15 Y-139.79 I0 J140.59248 R140.59248 F1800
It moved, but didn't appear to complete the arc, position in X was something like 1.6

So I'm a little lost how it works, if you do G2 X15 Y15 should your head start at x15y15?

zapta

Until somebody with coding skills will write a delta wipe generator script, you can compute the gcode with a spreadsheet like the example below (the values are arbitrary and not necessary realistic).

Edit: apparently gcodes G2/G3 do exactly that and most likely better

dc42

@blt3dp said in Nozzle wipe?:

Moved to the first position,
G1 X-15 Y-139.79 F1800
Tried to move to the opposite side along an arc,
G3 X15 Y-139.79 I0 J-140.59248 F1800
It kept giving missing I or J parameter

Which firmware version are you using?

To describe an arc centred on bed centre, you should use:

G3 X15 Y-139.79 I15 J139.79 F1800

The I parameter plus the initial X position gives you the X coordinate of the arc centre, and the J parameter plus the initial Y coordinate gives you the Y coordinate of the arc centre.

blt3dp

@Mysta
I understood that it moves from wherever your current position is to what you tell it in your G2 in an arc.

@dc42
Now I get how G2/G3 works, I probably was giving it locations outside of the printable area cause I was giving it wrong arc center coordinates.

I'm using firmware 2.02 Stable
I'd go to 2.04RC1, but I saw the issue with DWC not being able to connect to firmware.

Here's a question, my original goal was to start my arc at X-15 at a radius of 141 mm, which would put my Y position at -140.19986

I found that it would never go exactly there. I would issue a command to G1 X-15 Y-140.19986 and it would move, but it would end up at X-14.98 and Y-139.xxx

My printable area is configured as 284 mm, so 141 mm radius and X-15 Y-140.19986 should be reachable. I ended up at the 139.79 value from my previous example by moving X individually to -15 and then moving Y in increments until X changed. Then backed it off. Why would X change at all?

dc42

What have you set the bed radius to in the M665 command?

blt3dp

If I recall, 142

Mysta

Mines 225- ~~but when I look around the bed(which is set to build volume 450x450y and 225 origin offset I can move the piece around to like x300? I would think I would want to max out at 225?~~ Guess that's a S3d bug I've never noticed.

Would this be valid?

G02 X220Y0 I0J-220.0