Micro Mask usage question

homyakchik · Post by **homyakchik** » Mon Feb 20, 2012 5:05 pm

Hey, all

Well, my adventures into learning to paint something besides a Zoid continue. I've tried scotch tape to mask off areas for paint/no-paint (paint leaked underneath the edge), Tamiya and architectural/drafting tape (paint leaked underneath the edge) and now Micro Mask. (Currently I'm having to just rely on having a steady hand, which isn't always the case.)

I like micro mask; apply with a brush, trim (theoretically) with an xacto--what's to dislike? But usually when I apply it, parts of it peel right off (when I want them to; I haven't had one peel yet when it was inappropriate) and parts of it stick so hard that I've had to mar the paint job to pick them off (knife, dental carver, tweezers--sometimes the MM just laughs at erasers or scotch tape).

My question arises from today's misadventure. I wanted to paint black stripes down the length of a pair of cannon barrels. I measured points, used a ruler to pencil my guidelines on the painted barrels, and applied a coat of micro mask to both side of the lines. My thought was to use a knife to cut the mask, and then peel it away from where I wanted the paint, leaving me with a good paint job (for once).

This time, I masked the barrels last night, and came back to them early this afternoon. Parts of the mask would cut, but not peel cleanly; parts of the mask stuck as though its life depended on it. I wound up spending a half-hour getting the mask stuff off the barrel, and I'm back to trying to figure out the masking tape trick to do the painting.

The instructions on the mask bottle just say to apply with a water-cleanable brush, that it can be cut into patterns (I'd've not though straight lines such a problem), and can be peeled up when finished by hand or with scotch tape. Nowhere does it say how long to let it dry, or when I can safely paint over it, or anything like that.

Anyone with mucho experience with micro mask have any words of wisdom they could impart to me? I really like the ease of the stuff (applying), but haven't been very happy with the masking/trimming/removal results so far. *sigh*

Thanks

Davey

irishtrek · Post by **irishtrek** » Mon Feb 20, 2012 9:12 pm

What type of paint are you using, enamel or something else???

homyakchik · Post by **homyakchik** » Mon Feb 20, 2012 9:30 pm

I blush to admit that I use a variety of types. My preference is for acrylics (usually Model Master or Tamiya), for ease of cleanup and thinning. As I can't use my airbrush so much as I used to could, a lot of my base coats (the overall color of any given model) more and more often come from a Wally World Rattle Can (and I couldn't tell you what type of paint those are). For other smaller areas of color (greeblies and thingy-bits) I have some enamels (again, the modelling specific ones) and generic paint thinner to clean the brushes.

Up 'til this model, this mixture of types and sources has never been a problem. Of course, I've never until this model tried so hard to do STRAIGHT LINES, either, argh.

If not micro mask, any notions of effective paint-proof, arthritis-proof means of masking for hand (and occasional spray or airbrush) painting?

Thanks very much

Davey

homyakchik · Post by **homyakchik** » Thu Feb 23, 2012 10:14 am

Well, no one else seemed to know. Maybe it'll help others.

Micro's website features the information to avoid using it on acrylics, as both acrylics and micromask are water-based (or at least water-soluble). This certainly fits in with my experiments; acrylics (bottle or rattle-can), the micromask digs in like an anchor; I've still got bits and pieces of blue stuff that I can't get off my model without damaging scraping. Enamels (bottle or spray) and the stuff seems to peel off nicely. Wally*World rattle cans (I have no idea what they are) are a mixed lot--some, the micromask digs in even harder (if that's possible), and others, the stuff barely holds on at all. Lesson here: micromask is useless if you rely primarily on acrylics (at least, that's what it seems like to me), as I do.

I found we had a roll of blue paint masking tape. Cut my own edges. Had about a 95% blot-free success rate (and most of the blots are easily touched-up), which I guess is about as good as I'm going to get, at least for now. I'm definitely re-thinking my painting plans for my next model.

The Tamiya masking tapes that I've got are worse than useless. They'll barely stick, but they'll do that just long enough to fool me into painting; after that, I can count on bleed-under every single time. Peh.

Davey

riplikash · Post by **riplikash** » Thu Feb 23, 2012 1:23 pm

I don't have any experience with micro mask, but after reading your post wanted to offer some advice. You may already know this, but if not I figure you would like to know.

Some care needs to be taken when using a combination of paint bases, for a variety of reasons. First, they can expand and contract at different rates, which means if you are not careful, over time they will begin to flake. Second, they cure at different rates, so covering a slow curing paint (for example, oil paints can take days or weeks to cure) with a fast curing paint (acrylics) can cause issues as well, both because they are contracting at different speeds, and because they can interfere with each others curing process. Third, because the bases can be destructive to each other (the paint thinner used in oils and acrylics can really mess up some acrylic detail jobs). Finally, because they can interact...weirdly with each-other, making it hard to predict the effect you are going to get.

Now these problems don't necessarily happen every time, and with every kind of paint. But you can't really tell in advance, and since many of them won't happen for months, or even years, it's best just to avoid the problem altogether.

You can do this by following two simple rules: 1) acrylic goes down first, oil's and enamels only after you finish with the acrylic, and 2) seal between steps with a matt or gloss varnish. This will lock in the layers and keep them from interfering with each other. As a bonus, since many finish work techniques use oils/spirits and you have to seal anyways, you can at this point choose a matt or gloss coat depending on the type of finish you are going for. A gloss coat will really help oil washes travel and get into the smallest of crevices, while a matt coat will allow you to more easily apply weathering powders.

irishtrek · Post by **irishtrek** » Thu Feb 23, 2012 1:25 pm

Have you tried blue painters tape and from what angle do you spray the paint from, do you aim it at the tape or from the back side of the tape???

Lt. Z0mBe · Post by **Lt. Z0mBe** » Fri Feb 24, 2012 10:42 pm

I had the EXACT same problem with Micro Mask. I did two things:

1.) Use Tamiya tape! I think using some of Terry or Robb's sold me on it. Buy three or four different widths. They'll last as long or longer than that bottle of Micro mask, and are less expensive. They take curves better and are easier to position.

2.) For those times when I absolutely must have a liquid mask, I use Castin Craft latex mold builder. Note (I cannot emphasize this enough): It will absolutely etch SOME other latex/acrylic paints and not others. Test it first.

I hope this helps.

Kenny

homyakchik · Post by **homyakchik** » Sat Mar 10, 2012 6:33 pm

To all:

I'd known (sort of vaguely) that different types of paints will cure and harden at different rates. Considering that for this model I was putting a different color/coat on every four or five days, I think they were hardening pretty well (the base coat is sitll repelling pretty much everything else; I have serious concerns about getting a matte coat to take hold).

Most of the Tamiya tapes have proven useless to me (as noted); they'll go on and stick, but the paint always leaks under 'em (this may be because I'm brush-painting rather than spraying; I can't get my airbrush to work). Since everyone else still thinks highly of them, I picked up a really thick (couple of inches?) roll of the Tamiya yellow last time at HT; I'll try it on the next model built.

The blue painter's tape (with manually-cut outer edges) has been my biggest success so far. Again, I might have better luck if I was spraying, but 'til I can get the airbrush to work, brushing's it.

When painting over tape, I paint from the tape outward, as though I were dry-brushing, in an effort to keep the paint from crawling back up under the tape. Usually then I can actually dry-brush the edge of the tape/mask before loading the brush again. This seems to help the tape hold a mask better.

Big thanks, riplikash; I'll remember those for the next model.

Davey

JasonJDF · Post by **JasonJDF** » Sun Mar 11, 2012 1:17 am

A very simple tip that has always served me well is to use masking tape then spray a coat of the base color. This does two things, first it seals the edges of the masking tape and second, any color that bleeds under the tape is the base color. Once that has dried, and I usually don't wait as long as I would for a regular coat to cure, spay or brush the color you wanted to use for your stripe. It is also a good idea to run a sharp blade along the taped edges before removing the masks.
Your stripes or paint edges should be nice and sharp.

Joseph Osborn · Post by **Joseph Osborn** » Sun Mar 11, 2012 12:11 pm

Lots of good info in this thread. Does Micro Mask contain ammonia like many of the other liquid masking products? If so, that's why it attacks acrylics so badly. I saw a video of a guy who used acrylics to airbrush large-scale figure models, and he was using latex mold builder to mask different areas on the figure. He hit the acrylic paint with a spray of Testors Dullcote (or maybe it was gloss; it's been a while since I saw that video) before applying the ammonia-rich latex, so he avoided the bad reaction by sealing the acrylic.