Clean lines...

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Well-Known Member
Jul 10, 2004
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Hello, my question to all you great painters out there is how do you mask and get nice crisp lines when your done? Everytime I peel the mask off my lines are crappy looking.

My theory is to pull the mask right after each coat and then re-mask for each additional coat, but is there some other way? Thanks.
Well first off it depends a bit on what type tape you use. the "Blue Painters" tape works well and is easliy obtained and pretty cheap.
Then the technique. I've always let the paint dry completely then peeled off the tape. You could also take the time to cut along both edges of your tape line to make sure the tape is seperated from the paint on the roc...this requires a bit of a steady hand and patience.

To get twisted lines like the kinda most people use for flames you could buy striping tape. Electral tape works decent but is extremely sticky so i wouldn't advise it at all if you can help it.

As far as the way i paint. I use an Airbrush. not the type you attach to a propellant can either these tend to cause problems and deffects in the paint.
If you can afford it its a great deal to invest into a nice quality airbrush usualy around $70-$90 and of course you need a compressor of some sort that will operate at somewhere around 20 PSI.

But if you can't just get the most out of your spray cans. There are many people here that are pretty much experts at spray can painting.

Just experiment with different things do some research and find your grove. eventually with some practice you'll be turning out those crisp hard lines.

Good Luck!
Re: blue tape. I get paint wicking UNDER the tape. Ideas?

Re: airbrush. Recommendations on a model? I have a compressor, and consider that most of my paint goes bad before I end up using it all :-(
Sharp Lines are dependent on a couple things, the thickness of the masking and how well the edges are sealed before the second coat is applied.
There are any number of different masking media that will produce good clean lines if "processed" between coats.
Blue line is ok for large models, Parafilm-M is great for small model and tiny detail. as well as a bunch of liquid masking rubbers that dry to a 1 mil or less film.. all have their place. Generally for simple color seperations on standard and larger LRM models I use 3m fineline tape, it's greenish, only 1.5mils thick and available at most auto and sign supply stores. Another trick is to use scoch brand migic transparent tape on places you need a very small paint dam. simply "de-stick" some of the adhesive between your fingers before application.
NOW the real trick to clean lines! an Actual use for those testors clear coats. That's right clear coats! Burnish down your maskings, than quickly apply a light coat of matte or gloss clear to seal the tape edges. you must make sure ALL the egdes are down. allow the Matte clear to flash off about 10 minutes. than spary your next color. remove that tape and presto.. instant clean lines. if you used the Magic tape you won't have much of a paint dam line either.
I did a whole series of articles on finishing which are located in the Library section of if you'd like a lot more info on types and appliecaton of tapes, sheets and other makings. Look under Tech-Tips OO2- 005 if memory serves.
Hope this helps.
I use Tamiya Masking Tape (available at most hobby stores) for masking between colors and I have never (honestly) had bleeding under the tape. I leave it on for however many coats I am laying down (Krylon and Plasti-Kote) and then pull -- nice clean lines every time.

Example picture this case I painted the entire rocket Baby Blue, masked off the fins and painted the BT and nosecone Red Metal Flake.
I use frosted scotch tape ,,, leaves nice sharp lines
Blue tape is better than plain old vanilla masking tape, but it's not ideal - it still has a "crepe" like texture under which paint can seep. It's fine for house painting, but not so good for detailed models. It's better if you burnish down the edges and/or shoot base color or clear before putting on the next color layer - this fills the gaps in the crepe texture with base color, preventing bleed through. However, often times you shoot additional layers before the earlier layers have fully cured - I know this is not ideal, but it's a fact of life, too. A heavily burnished tape edge is more prone to lifting the base layers in this situation.

A better tape is fineline striping tape as it's more smooth (less chance for seepage) and flexible, so it can curve and conform to irregularities more easily. Hard burnishing isn't required so lifting of base layers is less of an issue - just make sure the edge is completely stuck down (a light burnish with an exacto handle or your fingernail).

There is another tape product I've used with good results, but the name escapes me. It's a brown paper tape with sticky stuff only along one edge. It is quite smooth so seepage is minimized and not super tacky so it's not prone to lifting base layers.

Micromister has good advice - parafilm sounds ideal if you have a decent source of it, and peeling the tape up soon after shooting (before full cure) helps in getting cleaner lines.

Finally, don't flood the paint on - that invites seepage. A technique to control this is to shoot a light mist coat to help seal the edge but not induce seepage, let it flash off, then shoot another layer to get the proper build.
I good brand is Paasche. They have a site do a search for Passche and it should take you to it. They are pretty good quality and for about $80. Try to get one with a double action chamber. These are more "fine tuned"
What kinds of paints do people normally use in airbrushes? I've only seen the tiny testors paint bottles, and the quart cans at the hardware store.
anything you can make thin enough to spray will work as long as you have the compatable thinner on hand to clean it afterwards
Originally posted by stymye
anything you can make thin enough to spray will work as long as you have the compatable thinner on hand to clean it afterwards

Also, unless the paint is specifically formulated for airbrushes (and sometimes not even then), you should strain it through something. I've seen people use old pantyhose or coffee filters.
As a major airbrush fan myself, I find it's the best thing for spraying rockets.

Two choices - single action (e.g. the venerable Paasche H) or dual-action (e.g. Iwata, Paache VL, etc...) For detailed modelling and fine lines, no doubt the dual-actions are better. For coverage of area and not-too-bad finer work, it's hard to beat the simplicity of a single action. A Paasche H with a "#5" tip can cover at least as well as your typical spray can, probably better, and is not at all sensitive to cloggling as the orifice sizes in that tip are relatively large. I.e. I never filter my paints when shooting through a #5. And I shoot every sort of paint imagineable including thinned latex house paint. The #3 and #1 tips on this airbrush make it pretty capable in the fine detail realm, just not as much so as a good dual-action. Plus, the H is dead simple to clean.

You can find a simple, new Paasche H on eBay for under $25 - though this typically is one with a single #3 tip and a single paint jar. Kits with multiple tips and jars can be had for under $50. In fact, I see one such kit there now for about $44 on a "Buy it Now" (no bidding) sale.

Well, if you really want great lines you will need to spend a few $'s. Blue tape that you get from a Home Depot is OK but you will get bleeding. The only sure way is to buy some 3M striping tape (1/8, 1/4, 1/2) and layout your strips after the base coat. Once you have sprayed go ahead and pull the tape. This will keep the lines fairly flush. When all is dry go ahead and wet sand with 1000 grit or higher and then clear coat. Time consuming and costly but you will love the results.

By the way, I use an airbrush with PPG auto paints. Tough as nails. Now if I can stop losing my rockets!
No one has mentioned 'frisket film' yet for masking. Glorified 'slightly sticky plastic film' that can be cut into shapes, have shapes cut from it (once laid down) It used to be a big 'must have' for air brushers..

Also, I have heard that certain spray paints have an 'additive' which leeches into the glue on masking tape, causing the dreaded 'underbleed'.
there is a paint that i get at my local hobby lobby called Createx. Its already thined out so all you do is shake it a bit and throw it in your cup and spray all day. And it cleans easliy and is extremely easy to mix to get different could also on the flip side use automotive paint in the little cups if you can find it.

I agree with limd21 airbrushes aren't hard to take care of at all. at max you could spend 10 min cleaning your entire brush system. and thats if you take it all apart and clean every part...which isn't needed often enough to even really worry about.
Originally posted by pr_rocket04
Hello, my question to all you great painters out there is how do you mask and get nice crisp lines when your done? Everytime I peel the mask off my lines are crappy looking.

My theory is to pull the mask right after each coat and then re-mask for each additional coat, but is there some other way? Thanks.

Whatever the tape, rub the edges down with the edge of a coin before starting painting.

Self-adhesive vinyl is more expensive but works very well for fine detail.