WHEN: Most Friday evenings. TIME:

04 October 2007

Gold dust true scale body prep tips for serious model car racers - from Jan Roestorf

Hi guys

I've been asked to run "the Aussie-way" past all of you.

This is what we do over here in Australia when it comes to painting and mounting bodies for a Plafit historic racing car:

1 - Planning and preparation:

Cut and trim (I use small files and sand paper together with scissors and sharp xcato knife) the clear (we only use use Lexan - bugger the cost, it's the best) body to fit the completed and race-ready, repeat, race-ready chassis. Normally, I'll do two bodies (one for practice and club racing, another for championships and concourse). The body fit must be so that it will fit over the chassis and rest on top of your test board around the chassis,making sure all the bottom edges are straight. It is also very important that the guide is not catching anywhere at this stage. If it merely touches the inside of the body it's OK.

At this stage it is a good idea to also trial fit the body to the chassis and to make all the required adjustments while you can see through the body. I suggest you read the last section now to see how the body eventually gets mounted. All this preparation must include all the trial fitting of scale bits and pieces as well as the interior. You only want to "assemble" the body after it's painted.

2 - Pre paint preparation:

I wash the body, like Rudi with some of the wife's dish-washing liquid, then I use tooth paste and a small, soft toothbrush to dull all the areas where I'll be painting - ALL ON THE INSIDE. Now dry the body completely and make sure you don't have any dust or fluff stuck to the body.

NB! - At this stage you need to do the decals if you want them on the INSIDE of the body, if so go to Applying and sealing the Decals - before you continue with this section.

At this stage I switch on my good florescent light and get my magnifier out. This is where the process of painting a body on the inside BY HAND becomes a joy or a pain. Grab your fine tip permanent marker and draw (using a ruler and other drafting aids) all the feature lines around the windows and lights (and any other detail you choose to do in different colours or where you need a painted edge. ALL ON THE OUTSIDE of the body. Let the marker dry. You will later be able to remove it with Benzine or leave it where you want a black trim line. Now you're ready for the paint job - go to painting the body.

3 - Applying and sealing the decals - ON THE INSIDE of the body:

Cut out all the decals and make sure you know what background they are printed on (some are printed on a white and not a clear back ground). Also make sure you decide which colour of the decal must go on first if it is a multi part decal. Finally, before you start, trial fit all the big ones and understand how they will position in relation to
complex curves.

OK get the flat dinner plate with water, a sheet of roller towel and all your aids. These will include a small tweezer, your decal set solution (to assist the adherence), your decal softener solution ( to make the decal soft and pliable) and a small paint brush with soft bristles. The tweezer is used to handle the decal together with it's paper backing when placing it onto the inside of the body, after it has been left in the water to loosen - but without taking it off the
paper. The paper will slide away once the decal is on the body and will not curl or fold.The small brush is used to position the decal on the body by dipping it in the setting solution and guiding it into place.

So now we know where the decals will go, let's start by placing the numbers first (leave the roundels for now if they are separate from the numbers), then the big prominent sponsor decals and last the smaller decals. Once all the decals are in position (look through the body from the outside and make sure all the proportion are correct),
leave them to dry out a bit. Come back after a beer/coke/tea/coffee and now place any roundels over the numbers. Also at this stage dab the small brush into the decal softener and drop small amounts of the solution all over the decals that need to take on the body shape. This may sometimes be over feature lines or over and around mudguards. ( I race a Porsche GT3 in Red Bull colours and the Red Bull with sun covers the complete side of the car from front wheel arch to back wheel - no problem). The hippie 917K is very easy to do this way. STOP, don't worry the softener will do it's trick, don't put more solution on - put the body away and let it dry over night if you can.

Once properly dry, inspect your handiwork and if there are any air bubbles or creases - puncture them with a pin and dab some softener on the affected areas. After a few minutes see how it's going and persuade the hard to please bubbles and creases with the small paint brush. Let it all dry again properly.

Very important before we start painting is to clean the body by wiping it lightly with a damp tissue or soft cloth. Some of the solutions used during the previous step may leave milky water marks and depending on the colour you will be painting, may discolour your finish. ( I don't worry too much if I'm going to use a light colour). Now get your Tamiya X type clear paint and paint around all the decal edges to ensure that no colour paint will seep under the decal when you paint the final colours. Let it dry completely while you get your final paint colours sorted out.

4 - Final painting - ON THE INSIDE.

Make sure you have a variety of good quality brushes with long soft bristles. I use PC paint, either Fascolor from Parma or Tamiya PC pots (unfortunately the best, but hard to find since Tamiya stopped production sometime ago). When I was in SA last year the guys at various hobby shops thought I was mad buying all their "obsolete" Tamiya PC pots.

At this stage you will have performed the "permanent marker" trick as explained earlier on - please check 'PrePaint Preparation' above. You may now also choose to use some masking, following the lines you've done with the permanent marker, but masking on the inside. I don't mask at all. First, you stand the chance of lifting up the decals when you remove the masking material, and secondly, if you steady your hand and lay your brush down over it's length, painting a straight line is easy. Anyway, practice make s perfect - and if you bugger up it's easy to fix. Here's how; let the PC paint dry completely, then it will scrape off cleanly and easily, you can then repaint the area.

OK if all done, let's start painting.

First paint white or silver behind all the number roundels and as many light coloured decals as you can without being too pedantic, whilst at the same time making sure that you cover the large see through decals properly. This will help the decals to stand out and contract nicely with the rest of your body colour(s).

Then use a small brush and paint around all the windows and lights, following all the permanent marker lines you can clearly see through the body - this lays the foundation for easy painting of various layers. You may also choose to paint around all the number roundels and light coloured decals in this way and the later paint over the back of them with white or silver. Then simply fill in the open areas and leave the first coat to dry.

Very blotchy hey? Yes, it will take a few layers/coats of paint. My Sunoco Porsche have two and my Yellow Hippie one has four coats. Yellow is the worst for covering and the dark blue or black the best. A tip to help here is to paint with a wide flat brush and to paint across the previous coat. If I start to paint from front to back, I'll then do the next coat from side-to-side, and so on.

When you can't see any pinholes through the body, held against the light, you're done with this part of your exercise.

5 - Final detailing and assembly of the body:

I use a very thin reinforced tape (made by 3M) to secure various bits and pieces to the inside of the body. I also use POLY ZAP, made by Pacer Technologies to glue any bits to the Lexan body.

Instead of painting the vents on a body, I use a sheet of matt black vinyl to cut the required shapes and then I stick it on FROM THE OUTSIDE, positioning it with the small tweezer. In some cases (like around the fan detail on the back of a 917) I will paint using Tamiya X type matt black. However, make a point of using a fresh pot of paint as the matt will streak if it's old.

To put the interior in, first stick some reinforced tape against the painted body where you plan to tape on the interior. Then place the interior and tape it in. Don't tape the interior so solidly into the body that the body looses it's flexibility. Stiff bodies are bad for handling. Now put a small piece of tape where the guide may touch the
body during a front end crash.

6 - Mounting the body on the chassis:

OK we're in the home stretch and the part I enjoy. I use a good quality contact adhesive and the rubber sheeting supplied by Plafit to mount my body. A clear see through test board is also a great help as you are able to see the body inside whilst fitted over the chassis.

NB!! - Remember, you read this earlier, if you did not, I hope your body fit is right.

First tape the H-plate and the main chassis plates together so that the chassis movement is 100% restricted, but make sure the wheels can still touch the test board. Also make sure that you don't interfere with the body mounting too much. (On the 1/32nd Plafit chassis there are two holes drilled so that you can screw the two chassis plates together for this process - but due to our 'no-modifications-rule' we can't drill any holes). This little exercise is required to prevent you from ending up with the body glued, having taken up the body movement and hence finding yourself with a body mounted incorrectly.

Now fit the body mountings to the chassis and check that the aluminum vertical sides are the correct length for your particular body. If not, cut them to size. Now roughen up the surfaces facing the body sides. I use a small file or sand paper. Now cut two strips of the black rubber (you only need to make it the same size as the aluminum surface that faces the body sides). Put some contact on the rubber and the vertical aluminum and stick together when ready.

Now place the body over the complete chassis with body mounts and adjust the body mountings so that the body slides with some resistance - not much - onto and off the chassis. Make sure you're happy with the fit and positioning of the body before you continue.

This where it starts making sense to have read this section at the beginning.

Now check where the rubber is touching the body ( very easy at the beginning when you can see through the body) and cut two pieces of reinforced tape to stick on the INSIDE of the body where the rubber mountings will be glued. Make sure the screws on the body mounts are tight (once they're mounted in the body, they will be difficult to tighten properly).

GRAB FOUR COINS (I saw Rudi using the same method in Witbank) and place them on your test board under the body. You can temporarily glue them if you like. This will provide enough free space over the top of the tires, inside the body. (This is why you need a race-ready chassis).

ONLY NOW, when you are perfectly happy, put some contact adhesive on the remaining rubber sides AND on the tape you've stuck on the inside of the body AND WHILE IT"S ALL WET place the body over the chassis with the body mounts mounted on the chassis. The body should fit snugly if you had done the earlier adjustments correctly. All that you have to do is slide the body forward or back to position it correctly on the chassis, apply slight pressure to the outside of the body where the glued areas are, AND WAIT. Being contact adhesive it is not essential that you get a complete glued together situation first time. Once the glue has dried sufficiently, remove the body from the chassis and press the mounting firmly against the body for a good glue joint. Some guys will now add some epoxy around the rubber mounts against the tape for further security - I don't bother.

7 - Fine tuning the body for racing;

Take all the tape off the chassis that you've put on before mounting. Put the body back on the chassis and tighten the lot. Put it back on your test board and check if the body is moving over and around the chassis as it should. I use the small 2mm brass washers that Plafit supply to space the body up and away from the wheels if required. Simply add the between the H-plate and the body mountings. I also setup my front and rear axles with the thin 3mm fiber washers so that I can add and take out depending on this fine tuning.

YOU"RE FINISH and you have a perfectly detailed SHINNY body that will last a long, long time (provided it's Lexan) without damage getting to the decals. maintenance is easy using the POLY ZAP for repairs and the decal setting solution where a decal may lift up. Just puncture it and put a drop of solution in behind it and PUSH down again.

Sorry for this rather lengthy email, but that's my whole story, I can't tell you any more. What's more I'm now tired and ready for bed.

Cheers mates

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