Step Test - first time.

[Stinkhorn Press]

Doing a step test. Looking to find out what exactly I should be looking for. And any clarification if I'm doing something wrong.

Mostly following the Murakami newsletter instructions http://www.murakamiscreen.com/documents/StepTestInstructions.pdf

110 mesh screen. Wood frame, tension probably in the 10-15N range.
Chromaline Glide. Glisten method, decent noticeable EOM.
Bank of florescent tubes.
Art was rectangle with 90% - 10% E/W tonal range (as opposed to just a field of 50%?) 24Lpi 22.5 degrees Accurip on epson 1400 1440x720 density 4.

10 steps. Ruby for light blocking. 50 seconds per step, 550 at the max. (200 seconds is our normal for a 110 and results in step 7 of a 21 step chart to wash out)

Did the exposure, washed it out. But now what? By my eye almost nothing is different. Hoping to stop by radioshak and pick up a loupe or lighted magnifier.
What should I be seeing? If I need to do it again, what element do I need to change?

[blue moon]

under the magnifier you'll see which one of the stencils has a good edge. Pick the one that looks the sharpest!

Usually you'll find sever that are pretty close. In that case we go with the lowest time.

at 24 lpi, you should be able to hold all of the dots. If anything is missing, you'll need to tweak something (film, emulsion, time . . .).

post some pictures!

pierre

[Stinkhorn Press]

How do you guys take pictures through a magnifier??

I had been aware of the 4/4.5/5 rule for determining mesh count to lpi count - but as soon as I learned it, I forgot about it - as the shop policies (when I took over) of thin emulsion, very underexposed was holding much smaller dots consistently than was what "recommended". They could get away with it, as there were very few runs over 100 to worry about.   

[mk162]

we used to go with a thin coat and underexpose, it actually works pretty well.  And it held up fine.

What is strange to me, does murikami recommend rinsing mainly from the squeegee side or the shirt side?  Their PDF is confusing.

[blue moon]

not sure what they say, but we pressure wash from shirts side ONLY! going the other direction blows out the stencil.

pierre

[mk162]

that is what I have always done, but then I started thinking "hey, i've learned things wrong before"

[Frog]

As for purposefully making a very thin stencil, you may find that your dots will not be as nice, and lines can be saw-toothed. The threads of the mesh itself will start affecting the definition as they come in contact with the shirt and block the ink.

There should be some good pictures of that here. http://www.theshirtboard.com/index.php/topic,2621.0.html

[Sbrem]

I would recommend a 110s mesh, as the thinner threads will let you make a better defined dot with a thicker stencil, in my experience anyway... with that thin stencil, you might define the dot, but it's uneven vertical shape will put down an uneven layer of ink, the individual dots will be of different heights, and any overlaying colors end up going down of a rough surface instead of a smooth one.
 

Steve

[Stinkhorn Press]

Had the screen guy take a look and he found some differences.
Anything 250 and under washed out clear and perfect (or too washed out at the low end).
At 300 seconds and up, there were places where it didn't fully washout behind the film, leaving corners and crusts floating around the edges.

pictures are kinda crap, iphone and cheap lighted mag.
the 250 is good (that corner knuckle IS clear, even if it's looking fuzzy in the pic)
the 300 pic has pieces I would have liked to have washed out.

we were exposing around 180 sec for 110 mesh, so we'll bump everything up accordingly for now.
Next time - smaller range of test times, tighter mesh, dehumidified screen, warm day - get some variables out.