Just out of curiousity do the pulleys appear to be really small compared to the shapeways and instructable walk through. I thought they were a bit small when I got them but they fit nice and I wouldn't imagine that pulley size would cause any adverse results if the motor speed were slightly altered.

Out of curiousity does it matter how the motors are plugged into the motor shield.Meaning while staring at the drawing surface does the right motor have to go into M1 and M2, and the left motor into M3 and M4 or vice versa? Before I permanently wire everything up to get final measurements I wanted to be sure.
A few pics of where im at.Motors need M3 hardware and there done for now. Just lacking the pulley cord...

Thanks. Im taking my time on measurements and setup to ensure quality.Im definitely planning on testing the wiring before I call it quits in that department and move on. Wiring on this project is far easier than anything else I've undertaken. I'll post more up tonight after my test on the running the motors again this time with both power supplies running. Any advice on a testing the motors and ensuring correct direction. Should it be as obvious as if I place the pen in the bottom center that the left motor should move clockwise and the right one counterclockwise to lower?

Got both motors to work in correct orientation. Had to rewire the left one briefly but it works. From home point to bottom of the page the LStepper moves CW and the RStepper moves CCW to lower, and reverse for raising up. Almost at the end of completing buildup.
All that is remaining is:
*Measure machine width and height.
*Cut spot in gondola for servo motor.
*Add counterweights to cord

Thanks sandy! This has been a enjoyable build so far. A quick question though. When you click render pixels in the controller does that start and initiate the drawing and can that drawing be paused if a low ink pen needs switching out and the drawing resume from the paused position and what angle is the servo swinging to lift the pen off of the page. The parallax servo I'm using is there standard limited rotation servo and it came with only the four way attachment so I plan on clipping the other three legs off since there isn't an alternative right now. Thanks for all your help and replies.

Gotcha! I plan on incorporating the servo shortly after I have run a few drawings through and tested things out a little further. This is my first drawing and where im set at right now:

*Machine width-762mm
*Machine height-1194mm
*Page width-457mm
*Page height-610mm
*400 steps
*no change on rev.step.mm
*Grid size-27
*Sample area-37
*Variable square wabe
*Bright pixel-255
*Dark Pixel-0

Pen was a Pigma Micron 0.30mm black. Is there a way to render more detail with another setting. When i did standard square wave it looked like it was going to color the entire page. Thanks again for the help.

Awesome! Thanks for the feedback. My gondola is taking on a kind of swooping circular pattern and I think I will adjust that accordingly for the next drawing. Im trying to set the home point as accurately as possible but what you may be seeing from the drawings are areas that im taping off the paper to the board and then removing it post drawing. What do you think would be good settings to move on to from here. I have kept the grid size at 20, and the sample area at 22. These are the two images that I did last night. Trying to correct the previous issues slowly but surely. How did you render the two color images from the instructables. Were there changes in dark pixel and bright pixel section or what else went on. I think I used on the first one variable sized squarewave and in the second variable frequency square wave.

First one Self Portrait.
Second Best friend Tyler

Photographing drawings is hard! They're quite indistinct - and I'd say for such small pixels you can make better use of your pen. There aren't any pixels which are fully shaded - solid. This is because you've got your pen width set to be bigger than your pen really is. Try knocking it down a bit, or set up, and do a pen width test to figure out what setting to put your pen width to.

The ones you're talking about on the instructable, which do you mean? The multicolour ones are done using a couple of different images, and the mask function of the controller ("pick mask colour" or something like that). You can see the current masked colour with the info overlay (press "i"). So for the penguin, I had one layer that was just the yellow parts, and all the rest was masked off with bright green, and drew that. Then a second layer that was just the red parts, and then a third that was just the black parts. Each time, use something like GIMP or photoshop to block out the detail I wanted to hide with an unusual colour.

Didn't use the bright/dark pixel theshold for those ones, but they are useful for that kind of masking.

Personally, I don't use a square wave pixel with any grid smaller than 40ish, because I think the dynamic range suffers too much (as well as taking forever), and if you do then use a very fine pen (as you are doing), and set the pen width carefully to get the maximum range in the pixel size you do have.

sn

Got slightly better results on this one. Still not there. The pen at least did not run out like I thought. Going to try and increase the grid size and sample area some more and run some more through it and see what happens.

Sandy, when you do work from a photograph what pixel pattern are you using most of the time. I'll test pens again tonight before I send another print through and see if I can't get even better resolution. Here is the one from last night with the original photo for comparison.

Hi, sample area is entirely "to taste". Bigger equals creates more blurred results, smaller creates more contrast between neighbouring pixels, so it's easy to come up with results that are jagged when representing small details like lines.

I think that last drawing looks pretty good. That's with scaled square, and it looks like you've set the pen size to be a bit more true? I really like the look of that pixel, and it gives a very good, half-tone style impression - newspapery. Quite good detail, probably better than the regular variable frequency square wave. At least, it's more representative than that the variable frequency one - I think it probably matches the eye's interpretation of density better.

I usually use the variable frequency one as my main pattern, because I enjoy seeing the pixel perimeters staked out in such a clear way.

sn