GMC DUKW-353 Amphibious Truck
Italeri Kit #6392
All Rights Reserved
For some reason, modelers take sport in panning Italeri model kits. Some deservedly so, but not others. This is an example of a long-wanted subject that Italeri released in answer to armor modeler calls that doesn't deserve a bad rap. It was a real joy to build - and looks in the end like a mighty fine representation of the real subject.
The original design and concept of the DUKW grew out of efforts began in 1940. Prototypes were designed by Sparkman & Stephens and built by the Yellow Truck and Coach Division of General Motors Corporation (GMC). The DUKW went into quantity production in Pontiac, Michigan from 1943 to 1945. 21,147 DUKW's were built overall.
GMC Model DUKW-353 was an amphibious six-wheel drive cargo truck built on a modified AFKWX-353 long-wheelbase truck chassis originally. The body was made of light sheet steel with an internal metal framework for reinforcement. Every DUKW was built with mounting brackets for the M36 Weapons Ring (often called a "Hip Ring"), and one out of every four was equipped with the weapons ring when produced.
The front deck of the DUKW had a folding surf shield mounted at the nose of the truck. Just behind the surf shield was a hatch covering the Radiator air intake, bow stowage, and air compressor servicing access. The large hatch behind this one was for access to the engine. The windshield surf plate was mounted here on the engine access hatch, when the DUKW was so equipped.
The cab of the DUKW had a swept-back folding windshield (early models was vertical) with side extensions, and a seating capacity for the Driver and Assistant. The cab floor and portions of the side walls were made of plywood. Normal truck steering controlled the DUKW on land, with the Rudder controlled by cable. Steering the front wheels aided waterborne control in tight conditions. All controls for operating the DUKW were located in the cab. Tire Inflation Controls were located both on the Instrument Panel and on the side of the Assistant Driver's seat.
The engine air intake was located immediately behind the Driver's Compartment, with fresh air drawn in through this grate-covered opening and pushed forward through the Radiator. This air flow was then exhausted out the side grills alongside the Driver and Assistant. The engine exhaust system exited through the right side grill as well.
Later DUKW's came equipped with Air Inflation Devices were bolted to the wheel hubs. A tin shield covered the air hose, which extended from the center hub to the air valve stem of the tire. This enabled the Driver to remotely raise or lower the tire air pressure according to ground conditions. The DUKW's tires tracked inside each other, cutting one set of tracks made going over ground easier, and the combat wheels used on the amphibious truck were 11 x 18 inches in size, rather than the 20 inch combat wheels used on other US vehicles of the period. DUKW tires were non-directional and had a different offset, with the lock-rings secured in place by nuts and studs as opposed to the bolts that were screwed into the rims of the 20 inch combat wheels.
The DUKW's cargo compartment came equipped with top bows for canvas, a removable plywood floor and stowage ares underneath for the canvas, bilge pump, and rear drivetrain access for servicing. The rear deck carried a spare tire, sand anchor, and gas (5-gal US Jerry Cans) cans. The Winch was seated in a cutout on the rear deck, with provisions to be used at either the rear or front of the DUKW. To either side of the Winch Mount were attachment points for an A-Frame boom assembly. Early DUKW's had wooden A-Frame assemblies, while the later models had steel A-Frames. The A-Frame was used with the Winch.
Standard accessories on the DUKW were its canvas cab and cargo compartment covers, sand anchor, hand bilge pump, pike pole (boat pole), a set of pioneer tools, rope bumpers, life preserver, hand & vehicle maintenance tools, spare parts, fire extinguishers, gas cans, spare tire & wheel assembly, and the M36 Weapons Ring on some vehicles.
Underneath the rear deck and cargo compartment was the Rudder and Prop Shaft. The Drive Shaft was external, and housed inside hollow tubes sealed with rubber boots. The drivetrain of the DUKW was GM's "banjo" type single reduction differentials - and interchangeable with other GMC "Jimmy" cargo trucks.
DUKW's cargo capacity was 5,000 pounds or 25 fully-equipped solders. Overland, the top speed of a DUKW was 50 miles per hour - waterborne was 6 miles per hour. The DUKW had a 40-gal fuel tank and a range of 240 miles on land, or 50 miles waterborne - water operation consumed much more fuel.
The photo above is a line drawing of critical measurements for the DUKW-353 Amphibious Truck. This is helpful, if you decide as I did to mount a weapons ring to your model kit.
The most helpful reference I found for building my model kit (aside from the Technical Manual itself) is the spread done on the DUKW in Ampersand Publishing's Allied-Axis: The Photo Journal of the Second World War - Issue #2. Other helpful books were Squadron Signal's DUKW In Action and Concord Publication's US Amtracs and Amphibians At War: 1941-45. On the Internet, I found three reviews and modeler's thoughts helpful in finishing my model. Ian Sadler provides analysis and thoughts, and both Bob Collingnon and Stephen "Cookie" Sewell are well-known, experienced, and respected modelers who provide thoughtful insight on the DUKW. Their review and impressions on the kit are helpful.
The Italeri kit really does cut a fine example of a DUKW-353 produced after 1943 - basic as it appears when first opening the box. The features and fittings on the DUKW changed during its production run, with the most noticeable differences being between the first 2006 vehicles and later batches. Confusion often arises because these interim batches aren't easily tagged - i.e. Model 1944 or Dash-7, or something like that. Photo reference is very important. The vertical windshield would be easier for a modeler to retrofit on their Italeri DUKW model, but the rounded nose would be a bit more difficult to reproduce.
It is also noteworthy to mention that the Italeri model kit does not provide the modeler all the little extra gear, cargo, and other detailing bits for fleshing out your model kit. Adding these isn't a difficult chore, and fun - as most modelers go on a "scavenger hunt" normally in completing a model anyway. Options to model an early-production DUKW or a vehicle equipped with the Air Inflation System or Wheel Pants are not included in this model kit. The M36 Weapons Ring or A-Frame Boom mentioned above are not included either.
There aren't many parts in Italeri's DUKW model kit. Not a really bad thing though, as you can move pretty fast in assembly and cleanup, leaving you time, energy, and sanity in contemplating the little additions that make an individual model special. I deviated from their suggested assembly instructions right from the beginning to make modeling life easier on myself, but was still able to leisurely complete assembly in the span of a weekend. The relatively few details provided in the basic kit pointed me in the direction of modeling a vehicle assembled in or after 1943 - a Korean-war era DUKW in the end. This required the least modification of the basic model kit, and called for small detail additions that kept it fun in the end.
I started out by assembling the boat hull. I felt as if I could have used another set of hands in putting these three parts together. In my kit example, there was no warpage of these large subassemblies whatsoever - which was great! Italeri's plastic responds well to Testor's Liquid Cement, and that's all I needed to join the hull parts together. I used Scotch Tape to clamp them together while the glue setup. I had some minor gaps that were filled with White Glue and or Gunze Mr.Surfacer 500 where appropriate - from the inside of the hull. No exterior seam filling was required after careful assembly.
The second place where an extra set of hands would have come in handy was putting together the axle subassemblies and getting them onto the boat hull properly. Wonderfully detailed, Italeri's DUKW is equally as nice on the underside as it is topside - maybe better. I found that using liquid cement to get a quick and strong bond on my front axle subassembly just wasn't going to cut it. I also found it increasingly cumbersome to try and hold it all together until the glue set. I used superglue and accelerator at the four points in which the leaf springs attach to the hull instead.
Having learned my lesson with the front axle subassembly, I went straight for the superglue and accelerator option for mounting the rear dualies to the boat hull. The attachment points were larger and probably really didn't need the quick bonding of superglue, in retrospect. The Combat Wheels fit snugly on the axle posts - if you don't remove the mold seams. I wanted to be able to take them on and off throughout the assembly, and yet still have tight-fitting tires in the end for final attachment. Once everything had setup on the hull, it was simple to go back and swipe little excess glue or mold release marks like the two little circles inboard on the axle mounts...
I then attached the Driver's Compartment Footboard (Part #2A) in place underneath the upper hull. I also cleaned up the ejector pin marks on the lower hull pan that are visible through the Engine Breather Grate (Part #15A). As mentioned above, there are parts of the real DUKW that are constructed with plywood. Italeri didn't model this feature with scribing a "wood" effect. I thank them for that. Armed with good references, a modeler can go to town rendering this effect on their own model - in their favorite way. I had to pre-paint / prime the interior portions of the cab during this stage of assembly - I doubt you could reach them for adequate paint coverage otherwise. The DUKW's major controls are present, and Italeri's dash panel is complete for the most part. Later DUKW's also had a First Aid Kit and Map Case mounted on the dash panel - not shown here at this stage of model construction.
For kicks, I took a scrap Italeri GMC CCKW-353 Transfer Case and installed it in the void between the two drive shaft humps molded on the lower hull. Its not highly visible centered underneath the Grate in the photo below - but it's there. Italeri doesn't provide anything to go inside the area - though you can see enough through the Grate to spot the void. You really don't have to go beyond that detailing point, but there's room if you're so inclined. With that little bit done, I painted the whole interior before sealing up the hull - no chance to get at it all later.
The upper hull fit so tightly to the lower hull assembly that I really didn't need any glue to hold them together. For piece of mind's sake, I slowly worked the joint with Tenax-7R liquid cement. The detail on Italeri's kit is quite delicate and understated. Heavy glue applications would melt this all away - a situation where Tenax-7R is ideal. I was left with gaps around the cutout for the Winch however. Instead of messing around with filling and sanding, I made a little box out of .005" sheet styrene to insert into the Winch cavity - covering up the gaps and keeping the assembly neat.
With the hull parts drying, I went ahead and put the wheels together. They fit snugly and cleanup just as easy. The Combat Wheels are noteworthy for how "squarish" the profile is. This helps - perhaps - to date them as later examples as used in the Korean War timeframe, as opposed to WW II Tires which appear a bit more "round" in profile. I'm quite sure aftermarket wheels will soon come along to make it easier for a modeler to render a WW II DUKW-353. Below photo: front tire standing, rear tire on right side and the spare tire on the left.
Another thought is that Italeri might have made attempt to model the Combat Wheels in a terrain condition other than running down a road. Consulting my copy of Form YT-4311 DUKW Amphibious Operation, the manual prescribes deflating the tires according to different ground conditions - ranging from 10 pounds for soft sand, to 20 pounds for hard sand or boulders (rounded rocks), to 30 pounds for sharp rock or coral, and finally 40 pounds maximum operating pressure for hard surfaced ground or improved roads. The setting of 10 pounds increased the ground contact area of the tire more than twice that of the tire set at 40 pounds - to improve traction and prevent the tire from "digging in". When I look at the Combat Wheels provided in the model kit, I can envision Italeri having made an attempt to model a tire set at a different pressure - like that of 30 pounds for coral or sharp rock littered beaches. Just a thought...
Interestingly, Italeri did not model the notch in the lock-ring where the Air Valve Stem locates on any of the Combat Wheels. This omission almost compels a modeler to scratchbuild a tire inflation system (not included in the Italeri kit) to address this deficiency as opposed to attempting to gouge a square hole to locate Air Valve Stems. However, not all DUKW's are shown equipped with this system - even those appearing as models produced after 1943 - though it was probably commonplace for a DUKW to have this system in place.
In my abbreviated assembly sequence, I left off all the tiny loops and details until just before painting. I handled the DUKW model quite a bit during assembly to get everything lined up and securely together - these details would have surely been destroyed in the process. To Italeri's credit, they cast them pretty fine - which translates to highly-breakable. The DUKW is quite a large model too - easily the longest 1:35 scale model truck I have next to the Dragon Wagon. If you take your time in the assembly process, the assembled DUKW model will have no wheel alignment problems, and the model will sit on all six wheels properly.
During assembly, I noticed small things like what appear to be mount points on the bottom of the interior boat hull that could accommodate an engine, the cutouts in the cargo bed walls to make attaching the top bows easy, and the like that causes me to ponder whether or not Italeri planned a follow-on DUKW Accessories Set to supplement this release. It would be an interesting answer to complaints about how "barren" the basic model kit comes presently.
Is the DUKW-353 big? Below is a photo of my favorite 35th scale figure "Sarge" who I used during modeling projects to help me visualize relative sizes of parts and components. I placed him in front of Italeri's DUKW model for a sense of scale - the DUKW is almost a diorama all by itself!
With the basic DUKW model kit together, I moved on to minor detail additions to improve the overall appearance of the miniature. To allow me to get into the cab easier, I left off attachment of the M36 Weapons Ring until later. I did decide to go ahead an model a set of Wheel Pants - on the front initially. These were pretty easy to render with sheet and strip styrene - no description beyond photos would be better.
To make these parts, I first drew a template on a piece of Evergreen #9020 .020" (.5 mm) thick styrene sheet, using the Italeri kit wheelhouse as a guide. I trimmed this out and sanded to adjust the fit. Once done, I taped the plastic sheet part into position front and back with lengths of Scotch Tape to hold it in position properly. The inner strip of the stiffener is made from a length of Edgerton Enterprises #62510E .010" x 1/16" styrene strip glued into position. It matches the detail on Italeri's kit molding nicely. It also forms the base of two little tabs on either end allowing me to glue the Wheel Pant into place in the end assembly after mounting the Combat Tires. The stiffener itself goes on top of this, and is a length of Evergreen #132 .030" x .040" styrene strip. This makes the little tabs stronger. I lightly beveled the edges of this strip to fit better onto the Italeri hull. Another length of this strip goes along the bottom of the Wheel Pant - below photo with the tape repositioned. I rounded the leading edge and tapered the trailing edge from top towards the hull and positioned it like in photos. It adds two more gluing points to secure the Wheel Pant in position. This part will probably be supplied by aftermarket manufacturers - but the whole exercise to design and create this single piece only took me 10 minutes. It is easy to do with four pieces of plastic and you don't have to wait!
To allow me to easily get the Combat Tires on my model after painting, I would not attach the Wheel Pants permanently into place - I used tape to hold them in place as above. This also afforded further opportunity to model rudimentary Tire Inflation System equipment. This is practically hidden with the Wheel Pants in place, but I modeled it anyway. I often change my mind later on in model construction, and if I left the Pants off - then the gear would already be modeled. However, when I finished the Wheel Pants, I decided that I liked the look of them in place on the model.
The Air Inflation System parts were constructed out of scrap resin shapes and styrene strip. Solder formed the air hose connections. Even if a mostly hidden detail - it does add some depth to the model in the end.
Italeri did not provide a small bulkhead in the cab that locates behind the Assistant Driver's Seat. This also makes a helpful attachment point for one of the Tamiya M36 Weapons Ring support legs too - which increased its value in adding to my model. Basic attachment points for the support legs are cast on the Italeri model already - the mounts themselves just need to be dressed up. They are triangular in design, and simple to render with styrene strip and a little creativity.
If you don't wish to go to these lengths to add Tamiya's M36 parts to your kits, Blast Models in France is offering a nice resin conversion set for you. You can also obtain a canvas cover for your cargo bed from Blast Models too. To mount my M36 Ring to the model at the correct height, I used a homemade jig as shown below. Tools like these are simple for a modeler to make on their own - and alleviate the need to "eyeball" everything.
Later model (after 1943) DUKW's could be found with a Map Case and First Aid Kit mounted on the Dash Panel. This area is bare on the Italeri model kit, and readily accepts this detail. Behind both seats, the the corners closest to the side walls, a Rifle Clip (outboard) and a Fire Extinguisher are mounted in the later vehicles too. Though not provided in the Italeri kit, most modelers have a couple of these items lying around in their spare parts bin. On the front deck, I replaced the Hand Bilge Pump with an example scratchbuilt out of brass tubing. The Italeri part looked a little thin as presented in the kit.
On the rear deck, I replaced the Italeri Jerry Cans with fine resing examples from AP Bayardi's range. I used Accurate Armour's US Army Jerry Can Holders to mount them - equally nice photoetched parts. The Winch Drum is wrapped with nylon string to simulate the cable. I also added two lengths of .040" styrene rod to replicate "all-threads" - the missing posts inside the Spare Tire hub to secure it into place.
The Cargo Bed of the Italeri kit is pretty nice as presented. Later model DUKW's commonly had five Cargo Hoops mounted there that are not provided in the Italeri kit. As the DUKW did so many things, this isn't a terrible oversight on Italeri's part - I'm sure there will be many different ways modelers will build and display their DUKW models. At this point, I added the fiddly (delicate) detail parts to my model. I would begin painting soon and not handling the model roughly from this point on. To Italeri's credit, they cast these parts as thin as examples found in AFV Club kits - and they break as easily too. The last thing I added to my model were front dressings to visually improve the engine air exhausts on either side of the cab. Italeri molded these grates solid, and I for one wish they had opened them up. I didn't want to drill them out at this stage of the game, but came up with a quick expedient to create an illusion that they might be...
On the next page, the painting, marking, and weathering commence...