Tips and Techniques

[jackfitz1944]

In this thread I would like to share some of the techniques I use to build 87th scale vehicles. I would also like others to share their methods. This can be a learning experience for all of this.
I have included a picture of my workbench, I didn't tidy it up, I left it as it was after working on the '37 Stude pickup. Other projects in the photo are a '38 Buick, a '41 Plymouth pickup. and a '41 Chevy Coupe-pickup (all made by Cutters). The Opti-visor and light are a must for old eyes like mine. The toothbrush is to wash castings with dish soap before priming. Also shown is a selection of paint, glue, paint brushes and tools. The tools I use the most are a hobby knife, emery board, tweezers, a pin vise, and different grades of sandpaper. I plan on showing a step by step description of the way I build a model.

[skunk]

Cool! I can't wait to see the rest of your work.

I agree with Christian that seeing photos (not just of finished items) is very interesting. Pictures of things that might seem boring to the modeller themself may be of great interest to other modellers. Inspiration as well as education. And perhaps we will also be able to offer you a tip or two!

[cfesmire]

Look forward to your sharing of techniques Jack.

[jackfitz1944]

The first thing I do when starting a new casting is to inspect it. Some things that need to be cleaned up are easily seen, like the mold flash around the wheel wells and along the bottom, as seen around the bottom of this Chrysler Airflow. I use a hobby knife, file, and fingernail file to clean this up. For the wheel wells I use a hobby knife handle with sandpaper wraped around it to clean up the wheel wells. I also inspect the casting with my Opti-visor for other imperfections. I like to wet sand the flat areas with 220 wet/dry sandpaper. For small pinholes (air bubbles) I have been experimenting with Krazy Glue (cyanoacrylate also known as CA) and Testors plastic model cement that comes in a tube. I put a small amount on a piece of brass wire and fill the indentations. So far it looks like the CA works better. I then sand the area smooth. For the flash that is between the body and the bumper on some castings I use a hobby knife to open a hole by spinning it as it bores a hole. I then repeat this step until I have enough holes to cut and chip away the rest of the flash. After the casting is cleaned up I wash it with dish detergent and a toothbrush and left it air dry.

[jackfitz1944]

Here is my technique on painting tires and wheels. After cleaning up the tire castings and painting the wheel, I stick the tire castings to an upside down piece of cellophane tape. I work out of the cap of the paint bottle with a very fine brush. I work on a self-healing work mat and stick a hobby knife in the tape so I can spin the tires as I work on them. This is my first attempt at painted whitewalls. I normally use Testors "Rubber" paint but this is a mixture of flat black, flat gray, and rubber. I finish the backs of the tires after the paint on the front has dried. When working on the separate hubcaps, I stick them on cellophane tape to paint after cutting them out of the mold flash.

[cfesmire]

Super results Jack. You've sanded all the mold lines off of the treads for a real uniform circle, the prep work means as much as the painting. Color looks good too.

[lordrusty]

I have a tip that I have been using for years on my 1/9 scale resin horse castings. To avoid those annoying pinpoint surface air bubbles, first powder the mold interior with ordinary baby powder.

Brush it around to cover all interior mold surfaces, brush out the excess, then using compressed air (from a compressor or "canned air"), blow the remaining excess away. Pour your resin into the mold, allow it to cure, and there should be no more of those annoying pin holes on the surface.

A phenomenon called "surface tension" is responsible for the formation of these air bubbles or pin holes. The application of talcum powder -- baby powder -- breaks this surface tension, allowing the resin to evenly and cleanly coat the interior surface of the mold, thus producing clean castings.

On the castings you have that need filling, may I suggest a filler putty? "Squadron" makes a white filler putty, as well as a red color filler putty, that works wonders on the pin holes found in many raw resin castings.

I have found it in my local hobby store. It is similar to the Bondo red filler putty. This is different from regular Bondo Auto Body Filler. This stuff comes in a squeeze tube, as does the Squadron brand.

You simply apply a light smear over the pin hole, quickly wipe away the excess, let it dry, then sand the area smooth. It can also be thinned with rubbing alcohol while applying it. Hope this will help!

John.

[Lee]

jackfitz1944 said:

If the left hand is holding the knife and the right hand is holding the brush, how are you holding the camera and taking a picture too.......

[jackfitz1944]

I wondered if anyone would notice I had both hands full. My lovely wife took the picture.

[jackfitz1944]

I'm sure somebody has done this before and maybe even posted it but here's what I did on my day off. I have some castings that look too small. So I decided to try and make them larger. First I took the casting and drilled a hole in the bottom and inserted a screw. I then pushed the casting into a blob of clay, moving it side to side and back and forth to enlarge it. I then mixed some casting resin and poured it into my ersatz mold. The photo below shows the process and the comparison of the original Walther's '48 Ford and my larger version. I'll have to do a lot of work to the casting to make it look good.

[Lee]

Very clever. After looking at your castings, I should just send you our molds and let you do the work. ;D