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screen printing => General Screen Printing => Topic started by: bryanprints on February 28, 2018, 05:20:14 PM

Title: Fleece Printing Automatic Press Problem
Post by: bryanprints on February 28, 2018, 05:20:14 PM
Running a three color job.  White underbase, white highlight, pantone matched color.  American Apparel F496w Dark Grey Heather.  Spray tack adhesive. 

I've tried basing at 110 and 155.  I'm at max off contact on my Workhorse Saber.  Screens are static at 25ish newtons. 

Still having my underbase white stick in the mesh if I try to two hit it or not cover well enough if I single hit.  When I go to print the over colors I can also see the mesh sticking a bit to the underbase.

Does anyone ever underbase with discharge or maybe dark ink?  Anytime I've tried to print a dark underbase it's always been a nightmare.

The print is very solid.  Feels like I'm fighting it on every head.  If it pulls up a small bit the reg is off.

Any one have some recommendations?

Title: Re: Fleece Printing Automatic Press Problem
Post by: ebscreen on February 28, 2018, 06:14:22 PM
Hopefully you are using at least a blend white as opposed to cotton. Those
things bleed something nasty nowadays.

Stir and warm your ink.

Stand your squeegee more straight up and down and/or use a harder duro squeegee.
Make sure it is sharp.

Discharge base is a no-no. It likely won't discharge enough, and top colors will shift reg unless you have
time/temp/tack down to a science.
Title: Re: Fleece Printing Automatic Press Problem
Post by: Atownsend on February 28, 2018, 07:56:49 PM
If the mesh is lagging behind the squeegee stroke, its likely that you need more off contact or higher tension. Ideally the mesh should snap off the substrate at the same speed as the squeegee.

If you need more OC, you can use some shim stock in the frame holder as a quick fix.

Title: Re: Fleece Printing Automatic Press Problem
Post by: bryanprints on February 28, 2018, 08:44:07 PM
Yep!  Blend ink.  I’ll try the shim idea. We used to do that on our old press. Guess I just didn’t think it’d be necessary on the new one. Well give it a go!
Title: Re: Fleece Printing Automatic Press Problem
Post by: kingscreen on February 28, 2018, 08:49:09 PM
Are you running a Flashback? If so, add 3-5 seconds to your programmed flash TIME.
This will hold the platens up longer and allow more time for the screen to release.
Title: Re: Fleece Printing Automatic Press Problem
Post by: bryanprints on March 01, 2018, 09:33:02 AM
I am running a FB. 

That's a good point, you're saying to do that in table up mode then correct?  Trick the machine to think the flash is running longer?

I'll give that a shimming it a shot!
Title: Re: Fleece Printing Automatic Press Problem
Post by: blue moon on March 01, 2018, 10:29:53 AM
you can also stroke longer than needed. It gives the screen time to get out of the ink.

pierre
Title: Re: Fleece Printing Automatic Press Problem
Post by: kingscreen on March 01, 2018, 11:17:07 AM
I am running a FB. 

That's a good point, you're saying to do that in table up mode then correct?  Trick the machine to think the flash is running longer?

I'll give that a shimming it a shot!

Table up mode, and adding time to your flash program. Extending the print stroke will help too as Pierre said.
Title: Re: Fleece Printing Automatic Press Problem
Post by: bryanprints on March 02, 2018, 03:47:26 PM
Thanks for the suggestions guys!  Ran em today and it worked perfectly.