Hawkeye’s Squawkbox

We originally published this as a “Featured Article” back in September 2006 on the Hawkeye’s Hobbies website. With the website makeover in full swing, I’m going to republish some of those articles to keep them accessible as well as a way to answer questions from the many new subscribers. This particular subject has been a topic of recent discussion on one of the modeling forums. Hope you enjoy reading this and the other encore articles that will be appearing soon. Gerald

Painting On the Tree - by Al Jones, Milwaukee, WI

There’s nothing unusual in the practice of painting first. There are some advantages which I will list. But, the hardest part for most people who try the system is choosing a proper kit.

Since you will not be removing most of the pieces from the trees before beginning to paint, you must have some reassurance in your mind that the thing is going to fit well, or you will end up removing all the paint in sanding, and fitting once you start assembly. So, pick a kit that has a good reputation for excellent fit as your first move.

Then, there are some parts that have sprue attachments on the exterior surfaces of the model. The new Razor Saw from Unique Master Models, which will be available soon here, at Hawkeye’s Hobbies, will remove 95% of sprue attachment plastic. But, some sanding will always be necessary on these places.

So, what I do is to cut the sprues into 2 inch sections which can then be glued somewhere onto the inside of the part where it won’t be seen on the finished model.

I use alligator clips to hold the sprue sections while I’m painting the parts which can then be stuck on a toothpick set upright in a piece of foam board (Styrofoam) while the part dries. The rest of the parts stay on the trees protected from handling fingerprints and other flotsam and jetsam until the paint is dry.

I should probably say something about sanding any plastic surface that will later be painted. If you want the paint on the sanded surface to look like the paint on unsanded surfaces, you need to make the sanded area look like unsanded plastic. I have pieces of wet or dry sand paper in my collection with grits from 400 down to 2000 which is available at auto paint stores.

But, even paper that fine is not enough. I use finger nail polishing sticks to bring the plastic surface up to the same gloss as it had coming out of the mold. You know the ones: they are multi-colored with the final buffing surface always a smooth gray color.

Start buffing with the rough surface; that’ll take out most of the sandpaper scratches. Then buff with the intermediate surface . . . many times this is the white surface. Finally, buff with the smooth gray surface and your sanded plastic will be ready for paint. One warning on the polishing sticks: watch out for rubbing in too much heat where the polisher will begin to break down.

The rest of the parts on the trees can then be painted immediately. The razor saw will take the parts off the trees after the paint dries with minimal touchup required.

Sometimes I touch up with the airbrush and other times with a hand held paint brush. Just a little dab’ll do ya’! I no longer use nippers or shears for removing parts from trees.

These tools crush/damage the plastic in your model if you cut close enough and sometimes those spots need to be fixed later. I don’t like to have to fix later.

OK! Everybody’s model building nightmare is fuselage seams and the leading and trailing edge seams. You need to have some philosophy here. My philosophy here is the KISS principle. You know, keep it simple s______!

I hate fillers of all kinds and avoid using them with a passion. If fillers are necessary (remember that when you choose a kit you are choosing one that fits well; so, you shouldn’t need fillers), use whatever you’ve become accustomed to: melted plastic, body filler, epoxy, super glue. Smooth the filled area with sanding or whatever your normal procedure is. Finish off with a polishing stick. If your filler is softer than the surrounding plastic, you may want to spray a coat of primer which you can then sand down and polish after the primer dries thoroughly.

Warning: NEVER use the intermediate and final polishing surfaces of a polishing stick on PAINT.

So, with regard to seams, in order to avoid using fillers, you need good parts fit, you need to get into the habit of carefully dry fitting parts to see if any tweaking is necessary before assembly, and you need to learn how to glue parts together in a way that produces plastic “bubble-up” along the seams. I use a “Touch-n-Flow” applicator with Weld On #3 liquid solvent for my glue. Good solvents will melt the surfaces to be attached sufficiently so that some of the plastic in the seam will “bubble up” from the seam when the parts are pressed together. It’s a good idea to use some kind of clamping system here so that the bubbled-up plastic does not sink back into the seam. Let the bubbled-up plastic dry thoroughly, a couple of days, and then slice off the bubbled-up plastic with a new #11 X-acto blade. Wallah! No seam to fill.

Protect the paint along the seam with tape. Currently, I’m using Tamiya’s masking tape because it comes off clean–it does not leave any adhesive residue on your paint. Another good tape is from 3M; it is the stretchable plastic masking tape used by house painters. Sand the seam lightly between the tape edges. Polish the seam and after removing the tape, touchup the area with your airbrush.

Why use this method? You never handle painted parts until they are thoroughly dry.

Fingerprints do not show up on these painted parts. During the assembly process, you are not stopping, starting, forgetting what you were doing because you have to paint and then wait for the paint to dry. You just proceed through the assembly process one step after the other. It is like you used to do when you were 9 or 10 years old and you put a kit together in one afternoon. It is much easier to remove paint from surfaces to be glued after the paint is dry then it is to try to remove the paint from those surfaces while the part is sticking to your other hand. Some guys struggle with touch up after the parts have been removed from the trees. For me, I figure I’m going to have to do some touch up anyway. Why not do it in an organized, logical way.

That’s it. No secrets. No special skills. Just straight forward model building. Ah! I can smell plastic. I’m gone!

Al emailed me an addendum:

Now, what do you do when the kit is less than a Tamiya? I still pre-paint parts on the trees? The worst moldings that have the large sprue attachments and 3-dimentional mold seam lines which are a big job to clean up . . . I just take those parts off the trees first, clean them up, attach short sprue segments to an inside surface, hook up an aligator clip, and go ahead and paint before any assembly. It is important to remember that glue does not hold well to painted surfaces; so, I still have some prep to do before assembly. My goal is to assemble these kits with little or no filler that requires sanding. Once painted, parts can be dry fitted, mating surfaces can be matched by sanding on a piece of 400 grit wet or dry paper that has been contact cemented to a piece of plate glass. My favorite filler is window glazing compound which can be applied to both painted and unpainted surfaces. A smooth steel tool–spatula, awl, exacto chisel blade, etc.–can be used to put a glossy finish on the filler which can then be painted immediately. No sanding, no waiting for the filler to dry. The one flaw in the filler process is that the glue joint where the filler is applied must be firm. Any flex in the joint will crack the filler. Remind me that later I should talk a little about gluing upper and lower wing halves. There is a philosophy that I use which is helpful and some techniques and tricks, too. aj

I will, and I am looking forward to including it here! Thanks Al!

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