SAS Jeep
by: Sonny Sy

Historical Background
SAS stands for Special Air Service; it is a Special Forces unit of the British armed forces founded during WW2, Captain David Stirling was responsible for creating this elite fighting unit in 1941. The North African campaign was fought primarily in the desert, Stirling had become convinced of the concept of a desert raiding force, Its mission was to infiltrate the enemy and create disruption by blowing up airfields. Initial tactics involved small raiding teams inserted behind enemy lines by parachute drop, plant explosives and return to base via land extraction by the Long Range Desert Group. This plan proved disastrous on several missions. Undeterred, they modified their strategy. By refitting some newly acquired US made jeeps, they would be able to conduct their operations wherever they wanted and fight with whatever they needed. The field modifications enabled the jeep to better operate for long distances in the harsh desert climate. Numerous machine guns were also mounted turning them into lethal fighting vehicles. The result was an impressive 400 enemy aircraft destroyed on the ground in less than 2 years of operations. This remarkable piece of desert war machinery is the topic of this little modeling project.

Project Background
The very first model I built 22 years ago was Tamiya's 1/35 scale SAS jeep. I was hooked on the hobby and a little obsessed with this vehicle ever since. 19 years later I've moved on to smaller scales and picked up a few new tricks to put up my modeling sleeves. I was itching to give the jeep another go, this time in 1/72 (braille) scale.

I bought a set of the much talked about (in braille circles at least) Academy WW2 Ground Vehicle Set. It contained a nice new jeep complete with a pedestal mounted .50 cal browning M2 machine gun and a tiny little engine under the hood. The set also contained numerous jerricans and boxes which I had hoped were good enough, more on this later.

In order to get started on this project, I scoured the web looking for war time photos of the real jeep. Every jeep had a different layout when it came to armament and stowage. I also looked at dozens of photos of other peoples models of the SAS jeep. These were mostly in 1/35 scale with a few 1/76 scale Matchbox or Milicast Models and the occasional Verlinden 1/15 scale version. There was also a rather rare 1/25 scale build from a Japanese modeler featured in Armour modeling magazine and a brilliant 1/6 scale mod by a local modeler/toy collector here in Singapore. With all these images flashing in my mind; it rekindled a modeling flame. I would build the best SAS jeep I could in 1/72 scale!

The SAS jeep had 3 distinctive features which appealed to me. First, it was laden with numerous jerricans and varied stowage. Second, each jeep bristled with machine guns of Browning and Vickers make. And last but not the least - the crew wore Arabic desert head gear together with their army issue desert khaki shorts and shirts. I would not be satisfied until I managed to render a painstakingly detailed replica of this vehicle in miniature.

The Bodywork
Our little project begins with the Academy 1/72 model of the 4x4 Willy's jeep. At first glance, I thought it wouldn't be too hard to make a nice model from this kit. Sure, I'd add bent wire for the handles on the side. Chop up the front radiator grilles like the real thing, and since I've already got my wire out, I might as well replace the seats to make it look more to scale. Then the only remaining challenge would be to find suitable wheels (more on this later), add stowage and figures then voila I'd be finished. How wrong I was, the front grille presented the first major problem.

The S.A.S. had cut off all but the 2 middle grilles in front of the radiator to improve the engine's cooling. I started chopping the Academy front grilles from the side and ended up with only 1 grille in the middle!? That's when I realize the academy jeep had the incorrect number of grilles. Looking at photos of other jeeps on the internet, it seems Fujimi's kit is the closest to the real thing. (This is the Achilles heel of the otherwise superb Airfix jeep.) My first attempt at fixing this was to remove all the slats from the academy grille and then build 2 new slats with sheet plastic. This didn't work out well enough as you can see from the photos. I ended up recreating the front panel from sheet plastic, and only got it passable on the second try. Next time I'll use a modified version of AirFix's grille.

Another thing that bothered me about Academy's front panel was that it looked a little bit too square when it fact it should be more of a wider rectangular shape. It turns out that Academy took some short cuts with chassis frame by making the portions over the axles a stepped straight shape, where the real jeeps had curved arches. Academy's shortcut necessitates a taller front radiator panel, and to a smaller extent, makes the model sit a bit higher. I decided fixing the chassis was going to be too difficult, so I had to live with a square front panel. I made the jeep sit lower by chopping off bits of the spring suspension mounting points. I finished up detailing the front end by adding the condenser can made from plastic rod with aluminum foil straps and a hose made from wire. The plastic front bumper was cut off and replaced with some bent brass sheet.

Next, I shortened the hood slightly and filed down the edge to give the appearance of sheet metal. In fact, I also filed the top edges of the jeepís main body to reduce the thickness. Next, I filled in the holes where the windshield connects to the body. I made new gear shift levers from wire and blobs of super glue and tamiya putty at the end. Also a new steering column was made from metal wire. The seats were replaced with Magic Sculpt cushions and metal wire frames. The rear bumpers were fashioned from brass sheets. I filed a couple square plastic rods to make the spare tire mounts. Replaced the side handles with metal wire and brass sheet mounting points. I Shaved off the rear side indicators, thinned them and re-attached them at a slightly lower position. Finally I added some stretched sprue to represent hood clips and the small hydraulic shocks. And I also filed in a couple of furrows on the driver side body panel where the tools of the original jeeps were mounted.

I left off the rear seat backrest, and used the dashboard as is, as this piece is nicely detailed.

Wheels
For me, the wheels often play a big part in defining the visual appeal of any soft skinned vehicle. However, in the world of small scale models, I've seen many a wonderfully detailed kit only to be let down by poorly molded toy-like wheels. Academy's 1/72 version of the jeep is unfortunately a good example of this. For although the tire's size (diameter) looks about right, the thread pattern is too big (resulting in less grooves) and is not offset. I would have been able to live with this in accuracy, but even the wheels didn't look anything like the real thing. The rims were too thick, the bulge is too small, with the wrong number of bolts and no hub detail at all. Other braille scale models of the jeep that came before this one also suffered the same wheel problems.

My initial solution to this problem was found in the 1/72 die cast jeep model from Hongwell's Cararama series. The tires had a good pattern and the wheels had excellent hub detail, though the bulge was on the small side. This was a definite improvement over Academy's wheels. Since I didnt want to ruin my nice little die cast jeep, I decided to make copies of the wheels for my SAS model. Using a squash casting method with some polymer clay, I managed to produce 6 new wheels, but I wasn't entirely happy with it.

Before finishing the wheel copies, I was able to get the Airfix 1/72 scale jeep (ex-Heller) from a local hobby shop. This model had near perfect wheels! With some modifications, I was convinced I could come up with something better than what I already had. My 3 main gripes with the Airfix wheels were:

  • 1.) The thread pattern on the tires was not offset.
  • 2.) All the wheels had same length hubs, in the real jeep, the hubs in the front were slightly longer.
  • 3.) The tires looked to be a bit narrow and a little under scale diameter wise. To fix these, I first made resin casts of the wheel halves (inside and outside). I then sandwiched some sheet styrene as I glued the 2 halves back together with an offset on the thread pattern. This was then re-cast as 1 whole piece and used on the final model. I wasn't able to do anything about the diameter of the tires, in fact the multiple casting processes probably shrank the wheels even further, but in the end I decided I could live with it.


There are a total of 6 wheels on the SAS jeep, and the overall detail improvement out weighed the problematic tires' slightly smaller diameter. This I attribute (as an excuse for my laziness) to them being worn down by constant use in the rough desert environment.

Jerricans
Like tires, most braille scale kits fail miserably when it comes to jerricans. Number one problem of course is having only one wide handle when in fact there should be three. The jerricans that come with the Academy kit are guilty as charged. They also suffer from having a simplified shape with poor lid details. I'm always impressed whenever I see a braille scale model with correct looking jerricans. There seems to be 2 common solutions to the 3 handle problem. One method was to use some sort of photo etched piece and another method was to glue 3 pieces of wire or stretched sprue. I couldnít find any suitable looking photo etched piece, while at the same time I wasn't prepared to glue 3 tiny lengths of wire to 11 jerricans. Yes 11, thatís why I like SAS jeeps, they've got loads of jerricans.

I was too stingy to buy resin jerricans online so I decided to make my own. Using the academy jerricans as a starting point, I stuck pieces of sheet styrene to get the correct size and shape - wider with rounded edges and a lip at the base for US style jerricans. For the German ones; these had wide chamfered corners and a groove running around the sides where they had welded the 2 halves together. Actually this should be a double groove, but thatís too small even for me to do in this scale. For the handles I glued 3 tiny strips of styrene, making sure I had a nice groove between the pieces. For the gap at the bottom of the handles, I had to be satisfied with just a depression instead of see through gap, this was necessary because I wanted to make one piece castings for each jerrican. More bits of plastic were used for the lids. Brass sheet was used to form the straps and brackets used to secure the jerricans on the jeep.

Weapons
Each SAS jeep had a unique weapons configuration. I chose the meanest looking configuration based on a photo that keeps popping up whenever SAS jeeps are mentioned. This combo featured a .50 cal browning machine gun in front of the front passenger seat and a twin Vickers mounted on an anti-aircraft pedestal in the middle of the jeep. For the browning, I used the piece that came with the academy jeep. I had to modify it to reflect the "air pattern" version which had a different cooling jacket for the gun barrel. A groove was cut into some wood forming a simple jig that allowed me to drill the numerous holes on the side of the gun barrel. The ammo box came from a Roco accessory pack. Brass sheet was cut into strips and bent to form the swivel mounts. For the twin Vickers, I modified a couple of white metal modern US M240 machine guns from a company called Continental Model Supply Co. The butt stock was cut out and new handles were added from sheet plastic and wire insulation. The pedestal mount is again made up of brass sheet and plastic rods.

I often see models of SAS jeeps with the ďgangsterĒ version of the Thompson SMG, though I donít recall seeing any photos of them using it. Anyway, I think this bit of kit is pretty cool. I made mine by chopping off the ammo clip and front end of a regular Thompson SMG from Hasegawa's US Infantry Combat Team. A small plastic disc was glued to represent the round ammo drum used in ďgangsterĒ version. A bit of wire for the gun barrel and a small bit of plastic for the forward grip was added to complete this weapon.

Additional Stowage
More goodies were added to emulate the look of the heavily laden desert jeeps. Wooden boxes and crates are resin castings of originals that I had made with plastic sheet. Ammo boxes are from Roco Minitanks. Duffel bags were sculpted in place with 'magic sculpt'. Small strips of foil were added to represent the straps that secured them to the vehicle. Sand channels were formed by punching holes into brass sheet. In order to get the right alignment for the holes, I drew the hole locations on some masking tape, this was laid on top of the brass sheet. I then hammered a pin into the brass to form the holes. The shovel is again from Roco Minitanks but I replaced the center bit with a piece of stretched sprue. A small piece of stocking was rolled up and painted to represent camouflage netting. I used some wire to tie it up.

Figures
Over the years, Iíve seen countless models of SAS jeep. Most are either stand alone models or incorporated into a diorama that depicts some form of relatively sedate scene. But for me the SAS story evokes images of action. I wanted to represent this dynamism with the figures on my model.

I started off by chopping up some legs from the old hard plastic Esci British 8th army figure set. I posed them on the jeep, and used blue tac to hold them into place while the super glue dried. The gaps between joint were then filled with magic sculpt. The upper torso and head were made from copies of Hasegawaís US Pilot/Ground Crew set. I used the head from the guy with a helmet in his arms for the driver. The torsos and passenger head came from the guy wearing a beret and sunglasses. The arms were sculpted using magic sculpt and so were the headgear. The steering wheel was assembled with the driver figure.

The figures were painted first. I used Tamiya fine surface primer (white) from a spray can. Then I airbrushed a basecoat of Tamiya red brown acrylic paint. Subsequent layers were hand brushed using Vallejo model color acrylic-vinyl paint. I only have a small selection of Vallejo paints, so I mixed my own flesh tones. The colors used were: Burnt Umber, Golden Yellow, Purpleheart, Light Flesh, Black and Iraqi Sand.

My best advice for painting figures is to use the best brushes. It simply allows you to place paint exactly were you want it. I used number 0 Vallejo Kolinsky Sable brush.

Painting the jeep
I primed the jeep lightly using Gunze Surfacer 1000 shot thinned with Mr. Color Thinner and shot through an airbrush. I tried to spray as thinly as possible so as not to lose any detail but still have a good surface for the paint to stick on. After drying overnight, I airbrushed a basecoat of Tamiya red brown acrylic mixed with a bit of Flat Black. Again, I tried to keep this layer quite thin but solid. I had to brush on the same mixture into the smallest nooks and crannies that the airbrush couldnít get to. Next layer was a coat of Dark Yellow mixed with a little bit of Deck Tan. This was sprayed mainly on exposed surfaces and just lightly going over the deep recesses. More Deck Tan and Flat White were added to the mixture and this time sprayed only on the surfaces that would be exposed to the sun. Mr. Super Clear flat was then used to seal the resulting pre-shaded model.

The next step was to brush paint all the details with Vallejo model color paint. This includes that tires, ammo boxes, seats, jerricans, shovel, machine guns and duffel bags.

Weathering began with a wash layer of dark reddish brown oil paint mix diluted with white spirit. For dry brushing, I mixed up a light yellowish tan color (also from oil paints). I followed this up with an even lighter almost white color paint dry brushed to bring out the highlights. I also used dry brushing to represent the dust accumulation on the tires. For the machine guns, I dry brushed some Mr. Metal Color Aluminum paint.

Chipping was applied with a brush. I used a mixture of Luftwaffe cam green plus Iraqi sand Vallejo paint. I tried to keep it to a minimum, concentrating on the fenders, bumpers, jerricans, the bodywork near the seats and where the paint would be subject to abrasion.

After chipping, the wheels and sand channels were glued on to the rest of model. I used 4 minute clear epoxy. The front wheels were glued at an angle.

Base
I took a wooden plinth meant for figures and stuck a piece carved Styrofoam on top. Thin balsa wood was cut to shape and glued around the Styrofoam and then stained and varnished. For the groundwork, I used Faller Hydrozell mixed with white glue and a bit of sand. This was built up on the Styrofoam in 2 layers. The tire marks were formed while the Hydrozell was still wet. White glue was brushed on and sand sprinkled on top to add more texture. Everything was brush painted with the Tamiya red brown/flat black mixture. Next I brush painted on a sand color mixture of Vallejo paints. I gave it a dark wash, and dry brushed with oil paints to bring out the highlights. I also dusted it with ground up chalk pastels. I had to repeat this a few times as I couldnít get the dusty sandy effect I was going for. That was partly because I didnít know exactly how this effect should look. At some point, I also resorted to airbrushing some shades into the ground work. When I finally settled on the look, I glued some fibers from a scale railroad grass matt product.

The finished jeep was mounted via wire stuck into a hole underneath the chassis. As a final touch, chalk pastels were dusted on the lower surfaces of the jeep.

A couple of light sprays of Mr. Super Clear flat sealed the Ďdealí and I was ready to call it a day on this project.

Photography
Shooting Braille models is a bit of challenge. I started taking ďwork in progressĒ pictures of the model with a Fuji film finepix f60 in macro mode. I was getting decent pictures but parts of the jeep were out of focus, probably due to the large aperture setting the camera had.

I eventually got a Nikon D80 digital SLR camera. This was used for all the finished piece photos. For the really close up photos, I attached a Kenko lens extender to the kit lens. This allowed me to shoot macro without getting special lenses. The downside was with my kit lens, I could no longer adjust the aperture. Luckily, the aperture was stuck at a small setting (f22) giving me a deep focus region. I had to shoot with slow shutter speeds Ė from 2 to 3 seconds for indoor day shots and up to 8 to 10 seconds for night shots. Of course this can only be done with a tripod. I also had to use the timer to prevent vibration when taking the photo. I also had to make sure I wasnít moving too much while the photo was being taken; even the floor vibrations affected the image.

The shots were taken at different times of day, and I had to adjust the white balance setting for color integrity. All the shots were done indoors. At night, I had a fluorescent desk lamp as the main light. During the day, I shot next to large open window. I used big white envelopes as bounce cards.

Conclusion
Well, Iím very pleased with the final result of this project. It took me 3 years of on and off building, but Iím really glad I stuck with it and finished it.

Although decent, the academy kit needed quite a bit of work to get a half accurate basic jeep. Using the Airfix jeep will definitely save you time and produce better results. Still, I am sure that all Braille modelers out there would be grateful if some manufacturer could come up with a jeep that is up to todayís mind bogglingly high standards for 1/72 scale.
Casting Process
Scratch building almost always eventually lead to casting. Depending on the master, I will make the decision to do a one piece or 2 piece mould. For 2 piece moulds, the next step is to determine where the parting line will be, usually locating it somewhere that is easy to clean up.

Procedure for 2 piece moulds
First I lay a slab of modeling clay on top of a piece of corrugated plastic board. I use the non-sulphuric, non-drying, non-hardening oil based clay or plasticine. The non-toxic version for kids should be suitable. I would then arrange the parts I want to cast on the clay; then press them in leaving half of the part exposed. For big pieces, Iíd dig up a small depression before I press the master into the clay. I will then add small bits of clay to the side, building it up to the exact shape I want the parting line to be. I use the blunt end of a paintbrush and sometimes the tip of a needle to get a clean sharp edge.

I also need to ensure that there is a suitable distance between masters and the edge of the mould. Nothing less than ľ inch is ideal. I also leave some room for the pouring channel. I use a section of plastic sprue for my main pouring channel. I will then use short lengths of wire or cut the smaller pouring channels between parts after the mould has set.

When Iím happy with the setting of half the master into the clay Iíll add the sides of my mould box using strips of corrugated plastic sheet. Then Iíll apply white glue to the corners to seal it. These days I use Lego bricks for the sides and seal the corners with plasticine to speed up the process.

The last thing to do before pouring rubber is to make the registration keys. I make this by pressing the blunt tip of a paintbrush into the clay around the parts. I press it slightly more than 1/8 of an inch deep. Also donít forget to apply a layer of mould release. I found that silicon rubber doesnít stick to styrene but does stick stubbornly to cured magic sculpt! Silicon rubber will also stick to silicon rubber. For mould release, I use Vaseline applied with a brush. I would first apply a generous amount to make sure I cover all the surfaces. After this, Iíd go over the parts with a clean brush to remove most of the Vaseline, leaving a fairly thin layer. I let this settle a bit before pouring rubber so that the brush marks disappear.

A word about laying out the parts; I donít use a vacuum chamber for casting though I wish I had one. So in order to get relatively bubble free casts, I place my main pouring channel so that it goes under the parts. This allows the resin to slowly come up from below thus reducing the chance to trap air bubbles. This technique works well for the slower setting resins. Of course the necessary vents still need to be made to ensure the air is allowed to escape from the nooks and crannies.

Now to pour the rubber, again, since I donít have a vacuum chamber, I have to develop a pouring technique that avoids air bubbles. I first mix up a small amount of RTV silicon rubber, just enough to for a thin layer over the parts, not more than 1 mm thick. I pour this on slowly and evenly over the entire mould box. Sometimes, I would take a metal paint stirrer and poke around the edges and crevices of parts to ensure there are no air bubbles trapped. Once I am satisfied that there are no more trapped air bubbles, I would then let this thin layer settle for a few minutes. In the meantime I will mix up more silicon rubber, this time enough to cover the entire mould for about half an inch from the highest tip of the parts. I would then slowly pour this onto one corner of the mould box, letting it push itself over the parts. As the mould sets, the air bubbles will rise to the surface, while the first thin layer ensures that air bubbles that donít make it to the surface does not stick on the surface of the parts. Itís a very slow process but is pretty fool proof.

Once the first half of the mold has set (usually 24 hours), I take the whole mould off the plastic base and turn it over. I take off the plastics walls so that I can remove the plasticine layer. I do this carefully so that I donít accidentally remove the parts from the first half of the silicon mould. Then I place the mould, rubber side down, back onto the corrugated plastic base. I rebuild the plastic walls around the rubber and again seal it with white glue. Then I brush on a thin coat of Vaseline over everything, same process as above. Then I repeat the rubber pouring process as previously mentioned. When its set, youíve got youíre 2 piece mould all set to go.

Casting
To make castings, I put the 2 rubber mould halves together. Sometimes I would use a spray on mould release which I found useless for rubber to rubber surfaces, but might actually help protect the rubber from the resin. I would then sandwich the mould between 2 pieces of corrugated plastic and use masking tape to tie the whole thing together.

For the jeep parts, I used a fast setting low viscosity 2 part polyurethane resin. I have problems with PU shelf life here in high humidity Singapore. After first opening the PU resin, the humidity in the air slowly degrades the resin causing it to produce air bubbles as it sets, very annoying. This happens even if you seal the container. The solution is to use up the opened PU within 1 or 2 months, or the whole lot becomes unusable after a while. For PU, I pour straight away after mixing the 2 parts together. So I make sure I avoid introducing air bubbles when mixing.

These days Iíve found a substitute for PU resin. Itís a product called Gedeo crystal resin. I believe itís an epoxy based resin. As the name suggests, it dry perfectly clear. Itís similar to Envirotex but a little bit less odour. Mixing ratio is 2 part resin to 1 part hardener. Pot life is almost an hour and sets around after 15 hours. Slow, but gives you a lot of time to eliminate air bubbles; perfect for home use. When mixed properly it will set to a hard finish that can be drilled and sanded. There is a bit of shrinkage but not too bad. I was also able to color it by adding small amounts of Tamiya acrylic paint after I mixed the resin and hardener together. Because of the long pot life, you can let it sit a bit after mixing Ė before pouring. This allows the air bubbles to dissipate.

To cast, I just slowly pour the resin into the main mould channel. When the resin reaches the top of the vents I stop pouring. You can tap the sides of the mould to release air bubbles. In the future Iím thinking of using some sort vibrating device to help get rid of trapped air bubbles. When the resin sets, take it out, trim the excess resin and youíre good to go. Use super glue to stick it to other surfaces. Prime and paint with normal hobby paints.





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