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screen printing => General Screen Printing => Topic started by: Rockers on June 12, 2012, 08:54:50 AM
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I`m really new to printing with an automatic. As a matter of fact 2 weeks new. But in these 2 weeks I could not really print much with the auto because of the wrong compressor we got recommended. Now I have to get these red polos out, 250 of them and have some issues regarding ink coverage.
Generally it`s a white underbase and then a red and a black. But somehow I never get a 100% ink coverage on the red and black. There are always little dots of white where there should be red and black ink. How can I avoid that. I tried more pressure but that just makes the black image bleed in too much and certain characters unreadable. i raised the off contact but no luck either. Did some adjustments to the speed of the print stroke. Well you name it I`ve done it.
My base is on a 128N
red and black each on a 166N.
Screen tension is around 25N.
Solutions please, I`m getting desperate.
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You are over flashing the underbase. I would go up in mesh counts as well to lay down less ink in the right place (on top). This way less ink = less heat needed.
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I would also seriously think about not even basing, but only running a highlight white. It looks like you are trying to get double duty out of your white, laying down more than is ideal on the underbase part, and, like printficient said, curing rather than just gelling it.
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I can't understand underbasing black at all, and if it's a red shirt, why not let the red shirt show through? Print black first, then the white, you probably don't even need to flash at that point. Of course, if the customer wants you to print the red, then black, white, flash, red. Just my thoughts, but we definitely don't underbase black, except in a very special instance, and I don't think this is one of them.
Steve
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Right there with you Steve. Underbasing black is just a bad idea a great majority of the time. It really makes the print look cheap and almost never looks good. I would knock out the black and the red. You will get a much cleaner and nicer looking print.
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And like I said, not only a base, but a solid base is going to amplify all of the drawbacks.
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Definitely agree--black and red on red polos the UB isn't worth doing--assuming they're all red. You should still be able to run black, red, white wet on wet--flash--white, and be off in one round even if you want/need to flash.
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To answer the first question you ask about ink deposit I,m thinking your base white is not smooth and thick which someone mention. Next I agree with the all other comments about not under basing black or the red if your printing on nothing but red shirts.
Darryl
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I have had this and I don't rememeber what I did to fix it. I think it was the white was not flashed long enough. Also clean the backs of all your screens to make sure they are clear. I had a ton of issues with under flashing my underbase when I started on an auto. Make sure your boards are hot when you start.
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I have had this and I don't rememeber what I did to fix it. I think it was the white was not flashed long enough. Also clean the backs of all your screens to make sure they are clear. I had a ton of issues with under flashing my underbase when I started on an auto. Make sure your boards are hot when you start.
I would suggest that as well. There are just so many little things that can cause this so make sure you change one thing at a time until you fix the problem and you'll know exactly how you fixed the problem.
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Rockers I agree with you on underbasing the black on this job. If you don't underbase the black then you will get the texture of the polo fabric in the black areas and have 2 levels to the print. With the underbase your print is all on the same level and texture. I think its a better looking print for this design, especially on a polo with texture to deal with.
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The idea of using black as a preventative measure from seeing the pique of the polo is a good thing to mention. Also, the OP didn't mention but it could be going on both black and red garments and is another reason to use black and red.
At any rate, my guess is as mentioned, over flashed. They do point out some very good tips about other reasons/ways of handling this so make note of it for future reference.
You mentioned the base was on 128N (What does the (N) stand for? Is that Newtons?
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"N" is Newman Roller Mesh. At the end of each number Don has the letter N, not sure why this was done and what purpose it serves but I'm sure there is a reason.
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Most of his problem is the substrate that he is printing on and not filling the voids in the garment with his base. Its all in the underprint.
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Are you printing base white under the black?
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Are you printing base white under the black?
I do, but judging by the feedback I get it might have been the last time I`ve done that.
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Is red the only color its going on?
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And the black.
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Sorry, Is it going on only red garments or are you printing it on other colors?
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Are you printing base white under the black?
I do, but judging by the feedback I get it might have been the last time I`ve done that.
I would certainly avoid printing white base under black ink. In all cases. This is what is making the black "shiny"
Also you can have the red shirt coming through on the red areas. Ideally you would use white and black ink only. The base white and top white can be the same film.
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live and learn rocker boy
we all do ;)
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I have changed just 2 things and the shirts came out perfect. instead of our standard Union white I used QCM`s simply white and changed as well the Union black for QCM WOW black. There was probably no need for using a different black but the white made the difference.
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Wonder if it was still just a flashing issue.
Different whites flash at different times.
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Wonder if it was still just a flashing issue.
Different whites flash at different times.
Its how the white was laid down to start with. He did not fill the voids in the garment completely. Changing the white probably fixed it because it was a different viscosity and he was able to get a better deposit that filled the voids better.
I sure hope he changed more than that though and did not base that black.
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Wonder if it was still just a flashing issue.
Different whites flash at different times.
I was thinking the same thing.
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There's a pretty large viscosity difference between the bucket of QCM 109 I have and the Union whites I have as well--if the Union ink was a little thicker and tackier, all other things equal it may not have laid down as smooth...
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For as long as I can remember, Union has encouraged modifying their whites if that is what it takes to clear the screen or get smoother results.
The argument used to be made that adding reducer will diminish opacity, to which they countered, clearing the screen usually helps opacity.
Likewise. a smoother finish could probably be achieved with the addition of base or reducer, but a lot of that comes with experience.
It's nice and convenient to have an ink work right out of the bucket.
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I am finding out that I am basing or reducing almost all my inks. I use to never do anything to them.
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For as long as I can remember, Union has encouraged modifying their whites if that is what it takes to clear the screen or get smoother results.
The argument used to be made that adding reducer will diminish opacity, to which they countered, clearing the screen usually helps opacity.
Likewise. a smoother finish could probably be achieved with the addition of base or reducer, but a lot of that comes with experience.
It's nice and convenient to have an ink work right out of the bucket.
Used to be? Heard it last week. ;D
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For as long as I can remember, Union has encouraged modifying their whites if that is what it takes to clear the screen or get smoother results.
The argument used to be made that adding reducer will diminish opacity, to which they countered, clearing the screen usually helps opacity.
Likewise. a smoother finish could probably be achieved with the addition of base or reducer, but a lot of that comes with experience.
It's nice and convenient to have an ink work right out of the bucket.
Used to be? Heard it last week. ;D
But I think that now, almost everyone understands the premise of a properly reduced ink completely clearing the screen is potentially more opaque than some unmodified ink not all making it through to the shirt.
There was a time when this was commonly an actual issue and choice to be made. Some folks really felt that they needed to suffer.
I will sound even older than I actually am but, like the kids in the Uverse commercials, "you kids don't know how much better you have it!" ;D