How to make an HO body

You loved them as a kid growing up in the "60's and '70's. Now re-live all of the thrills and excitement of HO slotcar racing and collecting in the '90's.

It began in the U.S. circa 1959 with the Aurora Model Motoring Turnpike sets. What started out as a "little toy buzz car" to supplement HO model railroading soon grew into a hobby sport of international caliber. Whether its vibrators, Thunderjet 500's,Tough Ones, AFX, TycoPro, 440's, HP's or Super G's, HO scale slotcars are back...bigger,faster and bosser than ever!

HO Scale Polycarbonate Body Shell Painting
Introduction:

Why use them? Vaccum formed clear polycarbonate (lexan/General Electric trademark) body shells offer several advantages over the stock bodies that are commonly found on cars. In reality,they are substantially lighter than the stock injection molded item. This usually translates to quicker lap times due to providing a lower center of gravity, better traction and improved handling overall. They are also inexpensive from $1.00 -$2.00 retail...they are expendable-your stock molded bodies are not! Finally they are usually the only way you can get a true reproduction of a current or vintage street or racing car. Several manufacturers produce finely detailed examples of HO cars in clear polycarbonate. Lancer and Motoi for the early narrow chassis; Thunderbolt,TOP,Parma,Madd,Scale Auto, Winn and Rhino for the later wide chassis. These are available either through well stocked hobby shops who cater to HO'ers (rather than ignore us) or through mail order houses. There are literally hundreds of choices. They are available in .007 or .010 thickness (the former for all out racing and the latter for mor detail and durability).

So now you want to try your hand at painting one of these little beauties...but wait! Put down that brush! Laying on a thick,goopy layer of paint with an ordinary modeler's bristle brush will not only produce less than satisfying results...but will load your body with excessive weight which will defeat the purpose of using a light weight shell.

Preparation:

Before you do anything in the color department you need to clean that body shell. Some manufacturers use mold release agents when producing shells which will interfere with paint adhesion. Use liquid dish detergent and water to wash, rinse well and dry with a lint free cloth. Then set it aside in a safe location.

Tools:

For best results...use an airbrush. Don't fear! It's fairly easy. I prefer the Badger 150 or the Thayer & Chandler Vega 2000. They are versatile, durable and relatively easy to clean and maintain. You will also need a sharp manicure scissors, a straight scissors and a roll of 1/4" to 1/2" masking tape.

Paints and Thinners:

Pactra brand R/C paint is the choice for beginner and intermediate. This paint is formulated specifically for lexan and comes in almost 2 dozen colors which can ce intermixed if desired. Another plus is that they screw directly onto the Badger/Vega jar adaptors. Some people prefer to mask off windshields and back and side "glass" before applying paint. I suggest using Hobsco's Magic Masker, Parma Liquid Mask or ( my personal favorite) Microscale's Micro Mask. All of them work well. Apply to the area before painting and remove them with a rounded toothpick only after the paint has set up. Use a gently rubbing technique to peel away the area.

Finish Application:

Apply the paint only after it has been properly thinned and mixed. Set you compressor to 40 psi. Avoid canned air or spare tires. Use a moisture trap. Set for a fine air/paint flow. Since you have infinite adjustments when airbrushing, it is critical to get the mixture correct usually through the trial and error method. Practice on clear plastic soda bottles first. Make sure that you properly thin the paint. If necessary use Pactra brand paint thinner. It is a mild laquer thinner base and it shouldn't crack, warp or twist your body like conventional automotive or hardware store thinners are prone to do.

The airbrush allows for fine control and you should adjust it such that you achieve a consistent even mist of paint. If you use too thin paint it will most certainly dry out brfore it gets to your body shell giving you a mess of micro paint balls. Too wet a paint mixture or holding the airbrush too close will cause paint drips, runs and sags. Please practice first for good control. Use adequate ventilation. Keep the paint schemes simple until you have gained experience and competency. Only after that should you attempt more intricate schemes such as two tones,striping,fogging and of course decal applications. Remember, paint in reverse. Darker colors first then lighter colors applied to the inside of the shell to achieve the desired effect. Use contrasting colors first for best results. Once the body has set up you can begin masking the outer shell for a guideline to trimming especially under the percieved rocker panels. Trim slowly and carefully. Sharp manicure scissors can now be used to trim the wheelwells. After cutting it is an option to use 1200-1500 grit automotive sandpaper wrapped around a pencil to smooth the arches.

With a properly applied finish, you should be able to have full coverage and NOT be able to see through the shell once you have mounted it on your chassis and place it on the track under normal lighting conditions.

Tech Tip:

When preparing bodies for painting, you might try laying the shell on a section of straight track first which will permit you to locate velcro attachments or the preferred body tubes and pins through the shell instead of through an already painted shell. This will give you a truer mounting on the chassis and allow you to adjust for tire, guidepin and pickup shoe clearance.

Happy Model Motoring!