TSB
screen printing => General Screen Printing => Topic started by: Wildcard on December 19, 2015, 04:27:52 AM
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I'm getting this issue with pallet tape forming bubbles, which then can turn into wrinkles when pushed flat again. It seems to be linked to jobs with greater flashing where the boards heat up, but only shows up after they have cooled down - like the next day.
The tape I use is regular sign vinyl application tape, I use 2 layers, and in this particular image I even used a bit of extra spray tac between layers to help keep it stuck. I've tried using wb table tac and spray tac on top but neither seem to stop it happening. Made sure I was applying it firmly, rubbed it down well, etc.
What am I doing wrong here?
(http://images.tapatalk-cdn.com/15/12/19/67e9e85fc823ddf71cc992ee8c430dc9.jpg)
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What is underneath? MDF, aluminum, soft top?
I get bubbles under my tape if I don't use a vinyl application squeegee during application. But I NEVER get wrinkles like that. I have silicone rubber tops on all my platens except homemade ones.
I use low tack transfer paper originally designed for application of vinyl decals for special circumstances. I think its R Tape brand, but it may be Transferrite. I'm not there to check.
If you have MDF tops, you just may have trouble for a while. I dislike them, but I know it is available with a smooth Formica like finish. "Melamine" is a word that sticks in my mind for the smoother finish. I've never liked the natural finish of MDF for shirtboards but I can't find the other type locally at the moment.
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The image is of aluminum pallets on the auto but I get the same issue on my rubber top manual pallets.
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Looks like you are getting small air pockets under the tape, when heated with the flash the air expands and makes the bubbles. R Tape here, little spot of spray tack in the two back corners and along the front edge. Secure the tape with an application squeegee to make sure there are no air pockets, if there are any I pop and smooth them and trim flush with the pallet.
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The issue is possible in your application. we use sign tape on rubber top metal pallets, (Vastex)
we have found that we can dramatically reduce the amount of bubbles with the way we apply the paper.
Here is what we do,
First like brother Itsalittlecrooked said we use a teflon sign squeegee to wack down the tape.
Our trick is to cover the pallet with a light coat of water base tack, cover 90% of the pallet with a TEFLON sheet from our heat press tacking down only about 10% of the paper with the squeegee.
Then we pull back the Teflon sheet another inch or two chase that section down and so on across the pallet.
This allows us to manage a 2 or 3 inch wide strip of tape at a time that seems to eliminate most bubbles and all wrinkles.
down the road when bubbles do pop up we eliminate them with a little hammer we made which incorporates a series of needles robber from our embroidery operation.
If you would like to buy a handy little tool to pop those bubbles try one of these.
http://www.monokote.com/accys/topr2190.html (http://www.monokote.com/accys/topr2190.html)
http://www.gpmd.com/cgi-bin/wgp569p.pgm?V=TOP&I=TOPR2190&DESC=Woodpecker (http://www.gpmd.com/cgi-bin/wgp569p.pgm?V=TOP&I=TOPR2190&DESC=Woodpecker)
called the woodpecker this "purveyor of puncture-ation" is used in a very similar operation to eliminate air bubbles in heat shrink covering applied to radio controlled aircraft coatings.
mooseman
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We have that happen if we mask the pallets hot, then run something and let them cool. If you just mask them cold or real cool, you should not have a problem. I've never seen it that bad masking a cool pallet.
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Mooses's tool also one-ups a standard ponce wheel for perforating old stubborn tape before soaking with one's favorite solvent for removal.
(http://www.monokote.com/accys/topr2190.jpg)
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I have rubber-topped steel pallets like Mooseman, too. All I do is peel off a sheet large enough to cover the pallet with extra all around. Keep it in a loose fold raised above the pallet, start one end at the front edge only letting an inch or so of the tape touch the pallet, then holding the other end with one hand slowwwwwwwly roll the paper towards the back as I use a nylon sign squeegie to smooth the paper down, pressing hard as I go but keeping the leading edge off the pallet. I never get wrinkles, and for the few bubbles I get, I poke the edge with the tip of an X-acto knife and squeegie the air out towards the hole with the nylon squeegie.
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I was too lazy to write all that, but Tom did. So all I have to do is say +1.
And I never get wrinkles doing it that way...ever. Basically, it is very close to Standard Operating Procedure for the application of transfer tape to weeded sign decals. At least the way I do it. My manual and my auto both have rubber tops on the regular shirtboards.
Bubbles, yeah. They happen. Poke 'em and forget it.
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Thanks for the feedback. Each time I've put new tape on i have become more determined to avoid the bubbles, and with this example there was 2 of us: I secured the corners firmly on one side and my helper pulled the tape taught above the board while I worked the tape down firmly in sections from one side to keep pushing air out. It was a cool pallet, and no bubbles to be felt or seen after application. Only bubbling the day after a job with warmed pallets...
So i guess I'll keep trying as all have suggested in these posts with their tweaks and hope to get it done better next time.
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I have rubber-topped steel pallets like Mooseman, too. All I do is peel off a sheet large enough to cover the pallet with extra all around. Keep it in a loose fold raised above the pallet, start one end at the front edge only letting an inch or so of the tape touch the pallet, then holding the other end with one hand slowwwwwwwly roll the paper towards the back as I use a nylon sign squeegie to smooth the paper down, pressing hard as I go but keeping the leading edge off the pallet. I never get wrinkles, and for the few bubbles I get, I poke the edge with the tip of an X-acto knife and squeegie the air out towards the hole with the nylon squeegie.
I use this method, but have a wide roll of pallet masking tape from my supplier.
Vinyl being what it is, I'm kind of surprised that could even be used for pallet cover without a risk of stretch, leading to some fashion of bubbling, but I guess it can.
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I have rubber-topped steel pallets like Mooseman, too. All I do is peel off a sheet large enough to cover the pallet with extra all around. Keep it in a loose fold raised above the pallet, start one end at the front edge only letting an inch or so of the tape touch the pallet, then holding the other end with one hand slowwwwwwwly roll the paper towards the back as I use a nylon sign squeegie to smooth the paper down, pressing hard as I go but keeping the leading edge off the pallet. I never get wrinkles, and for the few bubbles I get, I poke the edge with the tip of an X-acto knife and squeegie the air out towards the hole with the nylon squeegie.
I use this method, but have a wide roll of pallet masking tape from my supplier.
Vinyl being what it is, I'm kind of surprised that could even be used for pallet cover without a risk of stretch, leading to some fashion of bubbling, but I guess it can.
Where does vinyl come into it?
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I have rubber-topped steel pallets like Mooseman, too. All I do is peel off a sheet large enough to cover the pallet with extra all around. Keep it in a loose fold raised above the pallet, start one end at the front edge only letting an inch or so of the tape touch the pallet, then holding the other end with one hand slowwwwwwwly roll the paper towards the back as I use a nylon sign squeegie to smooth the paper down, pressing hard as I go but keeping the leading edge off the pallet. I never get wrinkles, and for the few bubbles I get, I poke the edge with the tip of an X-acto knife and squeegie the air out towards the hole with the nylon squeegie.
I use this method, but have a wide roll of pallet masking tape from my supplier.
Vinyl being what it is, I'm kind of surprised that could even be used for pallet cover without a risk of stretch, leading to some fashion of bubbling, but I guess it can.
Where does vinyl come into it?
Maybe I misunderstood Wild's post, but it said -
"The tape I use is regular sign vinyl application tape, I use 2 layers"
If that not vinyl?
I don't use vinyl, but from the picture, it looked like a similar product to what I might get from Diane (CYW) for a vinyl transfer.
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Most of the stuff we get as pallet tape, is repurposed application tape used for vinyl, but pretty much just appears to be a coated paper product.
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Interesting. I've always used a really, really wide masking tape product, the same masking tape material that a painter would use.
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Yeah, for the most part it looks and feels like masking tape, except maybe a little smoother texture and of course in a wide roll.
I figure they are all pretty much the same but there is a chance that I have a tape with particularly low tack or something?
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I get similar "bubbles" after the tape has been applied and I coated with waterbase tack and didn't print a job right away. If left over night its like the moisture in the tack or just humidity will make the tape come up in that kind of pattern. I just recoat with a thin 50/50 mix of tack (all my tack is cut 50/50} and then reflash. Never had a problem with the pallet tape creasing. It lays down nice and I am off and running.
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Yeah, for the most part it looks and feels like masking tape, except maybe a little smoother texture and of course in a wide roll.
I figure they are all pretty much the same but there is a chance that I have a tape with particularly low tack or something?
They do make low-tack (and high tack) versions.
Another thing we do is once you have the paper applied and cut, use the roll
as a sort of rolling pin on the pallet.
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It seems that the overarching solution to this particular issue is not one involving any tricky science of expansion rates of different materials or anything like that, but rather the simple one: learn to apply the stuff better dumbass.
Re-application will scheduled for right after the Christmas break as punishment.
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This. First learn to apply evenly as possible. Then, using the roll, start in the middle. Push forward, then back towards you. Tiny bubbles may be popped with a razor.