Puretch Photopolymer Solar Exposure with Space Bag for Photo Etching Demo #3

[Cristoviolanalgonas1]

Hello Jennifer,

Hey I have a question, how long is the film good for?

I bought some film from your website about a year more or less ago.

But i recently try to use it, and it seems bad, when I first got it it worked perfect.

But now some parts develop well and other parts not to good, it comes out uneven.

I keep it inside a sealed black plastic and dry place, don't know what happened to it.

Let me know when you get a fresh supply so I can order again.

[capefearpress]

@Cristoviolanalgonas1 The film has a one year shelf life. Many people use it successfully well after this. Store between 45 and 70ºF. The cooler it stays the longer it can last. Maybe your film got too warm.

[Cristoviolanalgonas1]

@capefearpress

Okay, now I know. I also want to thank you for the good advice you have me about etching presses. I'm going to be sending you another order soon thanks!

[Colhoon]

I make pcbs with inkjet onto high resolution paper (canon i250), print negative then after printing, use baby oil rubbed on the back with a tissue to make it semi transparent, 30 second exposure in sunlight works fine. Have obtained 8 thou lines and spacing if needed.

[capefearpress]

@Colhoon This is great to hear. What part of the world are you in? I assume you are using the Space bag here with the Puretch. Bravo!

[Colhoon]

@capefearpress queensland, australia .. I use the old top off a photocopier, the padded top and glass section and a couple of small plastic clamps.

My film is probably 5 years old and started having issues this week .. never fear (lol) got some more on the way from you thanks.

[dub1operator]

((((nice dub sound))))

[sunzoo1]

anything?

[sunzoo1]

My line work is opaque. No halftones. Just pure black and clear from transparency. Standard work you might see in the plastic kit hobby. Double sided to etch right through the brass instead of minor relief work. The reason I keep asking is because the resist did not leave a purple coating on the brass. I just got a slightly faded look where the resist should have been. Have done small test and it keeps turning out the same. I keep wasting material.

Exposure problem, right?

[rampandpark]

Have you etched one yet after doing a post exposure? The Your exposure may not be long enough but it's hard to say. This is why I recommend the stouffer. You may have enough film there to resist, don't judge by color.

What are you exposing with, how far from art and how long?

[sunzoo1]

Yes I have tried to etch. There was no sign of the resist after about a minute of etching. I expose using transparency paper with design on top of the resist for a few minutes in noon day sun. I'll try a few more experiments before I get a stouffer. Just didn't think I'd need one for pure black and white transfers. Thanks

[capefearpress]

Not sure what transparency paper is but if it's paper, this could be the problem as it's blocking too much light. You need to use clear film. I use Posjet. A few minutes in the sun with clear film would probably be too much unless you're at the North pole right now. Please e-mail through my site for further support.

[sunzoo1]

Do you need to do the stouffer step if your images have no halftone(pure black and white)? Is the space bag's use only for keeping everything stuck together instead of using tape? Is your puretch formula durable enough to be etched using a sponged filled with f. chloride instead of submerging in a tub? always nice choice of music, too.

[capefearpress]

Puretch is a high contrast film and won't work with a grey image. I know the stouffer is different densities of gray but it's which step the film quits exposing at which lets you know what's going here. Then you can do a proper exposure to a black and white halftone. I hope that makes sense.

[capefearpress]

The space bag works like a vacuum frame giving you good contact between the art and film. A vacuum will do this much better than tape or even a glass contact frame. The size of your dots or lines will determine how important your contact is. You could expose not so fine lines without a vacuum but not fine halftone. You should be able to use a sponge for very small plates.

[sunzoo1]

Is it possible to skip the stouffer stage at all; can I just leave the setup out in the noonday sun for a few minutes? Is there a such thing as overexposure. If so, what would happen?

[capefearpress]

What kind of image are you trying to etch? You can do small tests with the art you plan on using but the stouffer takes the guessing out. If you overexpose a fine halftone, very small black dots will not open up to be etched. It's harder to overexpose larger line work as long as your black is opaque.

[SoyJESUCRISTO]

so thats how puretch film is supposde to be used, now i know what i was doing wronge thanks for making this videos

[capefearpress]

What was it you were doing wrong? Glad this helped.

[SoyJESUCRISTO]

what i was doing was taking the top plastic off and puting on the positive, and i think this put moisture into the actual resist, so when i tryde to develop the film this afected the developing and not all the unexposed resist was coming off, but today i fallowed the same exact steps you show on this videos and it work perfect!