Very thin laser-printed decals

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sbaxter
Posts: 6843
Joined: Fri Jul 12, 2002 3:42 pm
Location: Tallahassee, Florida

Very thin laser-printed decals

Post by sbaxter »

Just looking for any tricks or strategies for dealing with very thin decals that seem prone to folding up on themselves as you try to apply them. I have a project (not a model) with a couple of quite large decals that I have already printed. I could always reprint and try again if necessary, but the paper isn't exactly cheap.

Thanks!

Qapla'

SSB
“The entire concept of pessimism crumbles the moment one human being puts aside thoughts of self and reaches out to another to minister to her suffering. The experience of either person can neither be denied nor adequately explained by a negative philosophy.”
-- Michael J. Nelson, Mike Nelson's Mind over Matters
seam-filler
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Location: Aberdeen, Scotland

Re: Very thin laser-printed decals

Post by seam-filler »

I've used this for the really large decals on car and airliner models. It avoids lifting and handling the decal and reduces the number of steps between dish and model and cuts the amount of water around, all of which help reduce the risk of folding, curling and crinkling. You could always test/practice this process using strips from the margins of your paper.
  • Get ready a sponge or soft foam rubber pad and soak it in warm water.
  • Soak the decal in warm water as usual, but do not leave it in the water until the decal starts to move. Instead, take out the decal on its backing paper and do not remove the excess water.
  • Lay the decal & backing paper onto the surface of the model, on or right next to where it is to finish up. The decal glue should start to soften. If it needs some encouragement, spray a little warm water.
  • Once the decal is loose, use the wet sponge/foam pad to ease the decal off the paper onto the model - the trick is to slide the paper away from underneath the decal rather than sliding the decal off the paper.
If your decals are really thin you might want to avoid using setting solutions. But another trick is to add a little setting solution to your soaking water. You then get some of the benefits of the setting solution, but being so diluted there is less likelihood of damaging the decal.
"I'd just like to say that building large smooth-skinned models should be avoided at all costs. I now see why people want to stick kit-parts all over their designs as it covers up a lot of problems." - David Sisson
sbaxter
Posts: 6843
Joined: Fri Jul 12, 2002 3:42 pm
Location: Tallahassee, Florida

Re: Very thin laser-printed decals

Post by sbaxter »

Okay; thanks! I have never used setting solution, but I am planning to apply some Micro-Sol to these after they dry. I wonder if there is any sense in leaving a decent margin of blank carrier film around the edges of the print when I cut the decals prior to wetting them; I was thinking that if there is a little folding over at the edges despite whatever I do to avoid that, it would stand a better chance of not getting into the actual print area, and I might be able to trim it away before applying the solvent.

The project, by the way, is applying a name and address number to our mailbox.

Qapla'

SSB
“The entire concept of pessimism crumbles the moment one human being puts aside thoughts of self and reaches out to another to minister to her suffering. The experience of either person can neither be denied nor adequately explained by a negative philosophy.”
-- Michael J. Nelson, Mike Nelson's Mind over Matters
Andrew Gorman
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Re: Very thin laser-printed decals

Post by Andrew Gorman »

Excellent tip, seamfiller!
Directly above the center of the Earth.
seam-filler
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Joined: Thu Apr 17, 2003 11:05 am
Location: Aberdeen, Scotland

Re: Very thin laser-printed decals

Post by seam-filler »

sbaxter wrote: Fri Dec 10, 2021 11:23 am Okay; thanks! I have never used setting solution, but I am planning to apply some Micro-Sol to these after they dry. I wonder if there is any sense in leaving a decent margin of blank carrier film around the edges of the print when I cut the decals prior to wetting them; I was thinking that if there is a little folding over at the edges despite whatever I do to avoid that, it would stand a better chance of not getting into the actual print area, and I might be able to trim it away before applying the solvent.

The project, by the way, is applying a name and address number to our mailbox.

Qapla'

SSB
OK - some extra challenges here.

Setting Solutions - I normally only use Micro-Sol (or the equivalent) only where there is a textured or undulating surface that the decal need to be softened to conform to - this, I presume, is going to be a fairly flat surface which should not need decal softening. However, I do use Micro-Set (or brand equivalent) on the surface before I apply the decal - this helps with adhesion.

I did a very similar project several years ago. I my case, the decal was applied to a brass plate (about 8 x 4 inches) and I applied the decal over the whole surface of the plate. The critical thing here was preparing the brass properly with polishing, de-greasing and lacquering before applying the decal. I used an inking roller to squeeze out any air bubbles (these would have really shown up against the brass).I had to be careful with the choice of final varnish because it had to be completely weather-proof. After all, rural Scotland can be a pretty harsh environment. I started with a few coats of my usual acrylic varnish and, once that was dry and well-cured, I applied a few coats of an exterior acrylic varnish. About 8 years later, the brass is still nice and shiny but the text itself has begun to fade - but I only had the use of an inkjet printer so I am not entirely surprised.

As for leaving carrier film edges, Unless you're doing what I described above, I would tend to keep the carrier film edges as close as possible to the printed area. If you're using the method I described in my first post, the fact that you are moving the backing-paper, not the decal means that you are much less likely to get curling at the edges. As I suggest, practice with scrap surfaces & spare decals. I would rarely plan to trim a decal once it is has been applied - so much can go wrong. I will admit to having trimmed the odd decal in place because things had already gone wrong ("Oh well, might as well") but I wouldn't recommend it.

Best of luck!
"I'd just like to say that building large smooth-skinned models should be avoided at all costs. I now see why people want to stick kit-parts all over their designs as it covers up a lot of problems." - David Sisson
sbaxter
Posts: 6843
Joined: Fri Jul 12, 2002 3:42 pm
Location: Tallahassee, Florida

Re: Very thin laser-printed decals

Post by sbaxter »

seam-filler wrote: Mon Dec 13, 2021 4:38 amOK - some extra challenges here.
Thanks for the additional information … but I already acted based on your earlier post, along with some of my own ideas. I did think of using a roller to help fight air bubbles; I used a foam paint roller lightly saturated with warm water. There were a few small bubbles remaining, but I pricked those with a pin and then applied Micro-Sol, which seems to have almost completely eliminated them. There were a couple of very minor fold overs around the edges of the decal, away from the print itself, but even without trying to trim them away, they are hard to see. I applied Micro-Sol to the entire surface three times, and now the edges of the decal film are difficult to see. If I hadn't done a light sanding before I applied the decals, you might not notice any difference at all. The main giveaway is a difference in gloss, since my sanding dulled some of the gloss a bit and the decal film is glossier.

I am SO ready to be done with this project. Lots of things have caused delays in finishing it, some not directly related to issues with the work itself, but plenty were. I've primed and painted the mailbox three times (using commercial spray paint), only to have the various clear coats I applied cause the underlying paint to wrinkle and crack. It didn't seem to be a matter of cure time, as that happened even when I had allowed the base coat to cure for at least two months in one instance. The first time that happened, I had masked and spray-painted the design for the name and address number using the same brand of paint as the base coat. The second time, my wife had painted it by hand with craft acrylics. The third time, I had tried what I thought would be a more benign primer -- but that time, I noticed that the only area of the paint that did not crack and wrinkle up was the craft acrylic lettering. After some more study, I got the idea that part of the problem might have been the mail box itself. It's made of aluminum rather than steel, and some things I read indicated that some primers have issues when applied to aluminum and can cause top coats to crack. I had spotted a Rustoleum primer specifically for aluminum on a trip to Home Depot, and went back the next day to get some -- and of course, they were sold out. So I got my second choice -- self-etching primer, which had also been recommended for aluminum. I applied that after I used aircraft remover, a wire wheel, and my random orbit sander to get the box down to bare metal (at least I didn't have to be concerned about it rusting!).

By this point, there was (and still seems to be in my area) a supply issue with spray paint, so I couldn't get more of the color my wife liked (an aqua-turquoise color). I ended up going to Hobby Lobby and Walmart to buy a bunch of bottles of craft paint in slightly different colors, along with a bottle of white, and mixing about 18 ounces of a close match for the spray paint color myself. I applied that with a small roller and a small brush, using numerous coats to cover the self-etching primer, then two full cans of clear gloss spray on top of that, which I lightly sanded ... and I finally applied the decals two days ago. Waiting for this coming weekend, presuming the weather is dry enough, to put two or three more cans of gloss over the whole thing and be freakin' done with it. It has taken me more than a solid year since I started to get to this point.

Qapla'

SSB
“The entire concept of pessimism crumbles the moment one human being puts aside thoughts of self and reaches out to another to minister to her suffering. The experience of either person can neither be denied nor adequately explained by a negative philosophy.”
-- Michael J. Nelson, Mike Nelson's Mind over Matters
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