This is a how-to guide on the application of water slide decals to plastic models. It's "a beginner's guide" because it's written by a beginner, and hopefully it's useful to other beginners.
You will need:
Some guides also suggest decal setting or decal fixing solutions, which I did not have. The only liquid I used was water.
0. Think about which decals to apply, and which order to apply them in. Practice with the less visible decals first, and apply the more visible decals later. Some decals might be easier to apply if the parts are disassembled first. Check the manual and prepare all the parts beforehand, so that you don't have to fiddle with wet parts later.
1. Cut out the piece of decal to be applied. I find it helpful to cut as large as possible so that there is more surface area for holding on to the backing sheet.
2. Drop the cutout into water for a second, then pick it out of the water and drop it on to the paper towel or napkin for a second. This is so that the decal is wet, but not too wet.
3. Clean the area where the decal will be applied, and place the wet backing sheet somewhere near it. The cleaning step is to avoid trapping bits of dust or lint under the decal.
4. Gently push and prod the decal with a tweezer until it slides off. The decal will initially be firmly attached to the backing sheet, but after 10-20 seconds, pushing it will cause it to slide, and from there you can slide the decal into position with the tweezer. This takes a lot of patience -- if you push too hard, the decal will break apart. But if you just wait and push it at sub-millimeter displacements, eventually it will move.
Some random video suggested letting the decal dry on the paper towel for 10 seconds and just place it on the model after that. The instruction manual says pick the decal off of the backing sheet with a tweezer and apply that. Those techniques didn't really work for me, I found it easier to minimize the distance between the sheet and the plastic and slowly slide the decal from the wet backing sheet to the intended position.
Be sure to adjust the decal position with a tweezer to keep it wet. Adjusting decal position with a cotton swab will cause it to dry prematurely, and a dry decal will not move.
5. Once the decal is in position, gently tap its edges with cotton swab to soak up excessive water. Try tapping at an angle that is perpendicular to the decal. If you tap at a more oblique angle, the cotton swab may push the decal out of position.
6. Wait for the decal to dry applying the next decal, or apply a decal that will be attached to a different part.
Few days after complaining about glue, I finished all the assembly steps for Nacchin, except applying decals. I don't remember my previous experience in applying decals, other than it was a pain, so I watched some random video on how to apply decals. I found the video helpful but it was more focused on how to make the decals look good, and I just want to know how to get those things to stick at all. So I have documented my experience in the form of a how-to guide. Hopefully someone else will find these notes useful, especially people who prefer reading text over watching videos.
At least for me, I still have a few more kits with decals that I haven't started building yet. Maybe next time I would be less fazed by those decals. I like how Kotobukiya included at least two copies of each decal, so there were at least two chances to get each setting right. Two tries might have been too optimistic, and there were a few spots where I ripped all available backup decals, so I just didn't apply those. Oh well. For the ones that did manage to stick, I had to admit they look better than stickers, because decals are a bit thinner than stickers.
I hate water slide decals. I love water slide decals.
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