Discharge and Water Base questions

[Binkspot]

We have been playing with the CCI discharge white and base for about a month, getting comfortable with it. Just received and started playing with the PC system over the past 24 hours.  I have been reading all the fantastic post in the other threads. I thought we were ready to offer it as a printing option then a few concerns came up. This past week what ever job was in the press at the end of the day I would clean the under base screen on multi color jobs or the white screen on one color and run a few extra shirts using the base or white as appropriate. Wash and dry the shirts and scrutinize them. Everyone was impressed with the results. Yesterday we ran black Beefy Tee's normal plastisol then did a few with the discharge white. After they came out of the dryer out of habit I did a stretch test and noticed it would crack like uncured plastisol. The image sprung back together when let go. Went back to my other test shirts from earlier in the week and they were fine but they were not heavy shirts.

Questions are:

Is it cracking and revealing black because the weave is looser then a normal shirt or not enough pressure or you can not use the discharge on such a heavy shirt, etc.

Can you discharge on 100% cotton sweet shirts or other heavy garments? More pressure lower mesh?

Do you mark up or up charge the price for a discharge or water base print?

WOW using only discharge and water base is there a limit before the colors bleed into one another?

Hard or light flood, which works better (I know every one is different)?

I have been using the Ink Cal app on my phone to figure usage for plastisol and usually very close, it also has calculations for water base which I will assume will be close also. Is there another method of calculating water base consumption since it needs to be mixed as needed.

How much extra ink should be mixed for a normal run 5, 10%?

Is there a way to save unused discharge or water base or just discard extra.

Other then emulsion is there anything else that will be damaged by the discharge? Any problems with squeegee rubber breaking down, corrosion of flood bars, etc?

Do the squeegees loose their edge faster running water base?

We use packing tape to tape the sides of the screens and Scotch tape on the bottoms for reg marks and or pin holes. Will these still work or will the water base make them come loose.

We print a lot of boxes with acrylic paint, use Textile PV emulsion which will last for a few hundred boxes before breaking down. Would this work for short runs, maybe 100 or less? I have a quart of the WB-25 that we will try later.

Any extra steps when doing a color change on the press? I will assume just use a wet rag to clean the screen out?

Any additional work needed to reclaim screens other then the usual?

Do the screens and equipment need to be washed or rinsed off as soon as the job is done? In other words can I pull a screen and put it right in our reclaim rack and possibly sit for a day or two before being reclaimed or should it be rinsed out with water before putting it in the rack and set over night?

Will the WB or discharge kill the dip tank?     

Thanks in advance





 

[jasonl]

I had the same problem with cracking whites, add 10% water to your mix and it should go away.  It did for me.  You have a lot of good questions so hopefully lots of folks will chime in.

[jasonl]

BTW, what is this phone app you speak of?  Gotta try that.

[tonypep]

All will be adressed and revealed. Stay tuned and don't forget to read the trade rags. Some of those peeps actually know what they are talking bout. Seriously though send me a p-mail

[Binkspot]

BTW, what is this phone app you speak of?  Gotta try that.

Its called Ink Calc from the screen print store. I did a search on "screen printing" one night and it came up.

[ebscreen]

Heavier garments like Beefy tee's do require more saturation. More saturation requires more
evaporation before the discharge process starts. Add to the fact that you've covered your water
layer with a non-breathing plastic layer and you've got your answer on that one. Longer
dwell time should help.

We print %100 cotton sweatshirts just like we would regular shirts.

If something needs to specifically be done with discharge (IE the client asks for it)
we occasionally mark it up, depending. Some jobs are just easier run with discharge,
so we do it and don't upcharge. Contract is always upcharged.

WB colors blend, very well. This is part of their attractiveness. It also means that butt reg
had better be butt reg, etc.

Light flood, you want a thick layer of ink to keep the screen from drying in. That said we'll start
to move the floods down as we get near the end of a run to be sure that we're getting full floods
with diminishing amounts of ink. Rarely see any difference unless you're really squishing it through.

On custom mix colors we make sure there's enough from the initial mix for the entire run. For white and
such we'll mix several batches throughout the day. Estimating wb ink usage is a little more difficult
due to the level of saturation, which will change the amount of ink used quite a bit, as opposed to plastisol.
Experience will kick in at some point and you'll get closer.

Never seen anything other than emulsion damaged by WB inks. Maybe pride, but that's it.

We avoid reg marks whenever possible (MHM FPU allows this) and when not possible we place them high
enough above and far enough below to not have to have ink travelling over them. (IE setup job then shorten
stroke/flood length) You really don't want any tape on the back of the screen at all. We will also occasionally
tape on the ink well side of the screen, after setup, before inking. There's an art to it though to make sure the
tape isn't lifted by the squeegee/flood though.

We use Murakami Aquasol HV and a post exposure and wipe on hardener on long runs. No problems
on 10K plus runs. I'd go Diazo if I could stand the exposure times though.

WB screens are reclaimed immediately after use. Or at the very least get all of the ink out. Do NOT let sit.
And no ink in the dip tank of any variety.

[Rockers]

Is there a way to save unused discharge or water base or just discard extra.






 

We are testing a discharge ink from an Italian company which can be kept activated for at least 6 month. It will not go bad during that period of time. All you have to do is keep a lid on the pot of activated ink. But that`s the only discharge I know of that can be kept.

[BorisB]

Is there a way to save unused discharge or water base or just discard extra.






 

We are testing a discharge ink from an Italian company which can be kept activated for at least 6 month. It will not go bad during that period of time. All you have to do is keep a lid on the pot of activated ink. But that`s the only discharge I know of that can be kept.

Would you mind sharing which italian ink brand this is?

[Rockers]

Is there a way to save unused discharge or water base or just discard extra.






 

We are testing a discharge ink from an Italian company which can be kept activated for at least 6 month. It will not go bad during that period of time. All you have to do is keep a lid on the pot of activated ink. But that`s the only discharge I know of that can be kept.

Would you mind sharing which italian ink brand this is?

Sure. They are called Virus.
http://lunicatools.files.wordpress.com/2011/09/brochurevirus2010d.pdf

[BorisB]

We tested their DC inks two years ago. They are very similar to Magna Colors from UK. Nothing very outstanding for my shop. But didn't know about 6 month pot life. They didn't mention it in their documentation. See links below.

CCI is way better. More opaque and easier to print. For my Shop that is.


http://dl.dropbox.com/u/14537899/Eco%20Discharge-ENG.pdf

http://dl.dropbox.com/u/14537899/HYDRA%20FLASH%20NOTES%20ENG.pdf

[Rockers]

Which discharge did you use from Virus?
The discharge plus which s their regular discharge or the Eco discharge?
I'm talking about the regular one which is still certified by OEKTEX II.
Next I will probably try Matsui's new Eco discharge.