Plastic Models – Getting Off to a Good Start

So, you got a brand new plastic model kit ship with a gazillion pieces and you want this one to come out good enough to display on the mantle. Now where do you start.

You’ll be a lot happier if you deal with the manufacturing imperfections before you begin your creative work. When you open the box you will undoubtedly find the plastic parts large and small molded onto trees and in plastic bags.

1. Inventory your kit with two objectives in mind; making sure all parts are present and observing the overall condition: note all the flaws the parts have – mold lines, pin holes, sink and swirl marks, warpage, and flash.

2. Deal with any issues from the first step. If you need parts, contact the manufacturer and expect a delay for delivery. Most manufacturers will help you deal with missing part issues. If you need to correct flaws, do it now before doing any painting or removal from the trees.

Mold lines: these are very small raised lines on hull pieces, running along sides of a mast or over raised portions. Some are more pronounced than others. The more recent plastic kits have been improved and, you will have hard time finding mold lines. They are easily removed with fine sandpaper or sanding sticks.

Pinholes: you will find these small round holes in the plastic, caused by the pins that push the part from the mold. In newer kits these marks have been eliminated or are in concealed spots. Try test fitting the parts to see if the pinhole(s) can be hidden. If so, sand the surface smooth. If it is deep enough, fill it with putty or body filler, and then sand smooth once the filler is dry.

Sink marks: most are depressions in the plastic flat surfaces like decking caused by plastic shrinking while it’s cooling. They can be any shape or form. These should be filled and carefully block-sanded before spraying primer. Flash Its the most common defect on plastic parts (especially those produced on old tools), but it is easily fixed. Just cut off the flash with sharp hobby knife, and sand the rest with sandpaper, sanding stick, or needle files.

Warpage: this occurs when hot plastic parts are dropped into a box and deformed under their own weight or weight of other parts. Basically, it’s a part that has wrong shape or is twisted. If the warpage is minimal, you can try to fix it with hot air from the hair dryer. Warm the part by blowing hot air on it, and carefully and slowly bend it into correct shape, then wait till plastic cools off. It should hold new shape.

When the body is seriously warped, you can try the following (and this is not recommended for children under 14 or should be supervised by adults) method: boil some water, take it off the fire, and let it sit for few minutes. Then briefly dip warped part in the water, and quickly remove it. Then bend it to shape, and hold until plastic cools off.

Safety Note: Keep in mind that after you pull the part out of the (almost) boiling water, it will be extremely hot. Please wear gloves or other hand protection while handling the part.

Here is more on How to Model Plastic

Post time: 06-06-2017