Caterpillar D7 Bulldozer - Hydraulic blade version - case report.
Autor: Panzerserra | Publicado: 2016-11-06T09:27:00-02:00


Soldiers!!

&nbsp; &nbsp; &nbsp; Let's meet a brave and strong girl, who was facing the worst working conditions to allow the fight to develop in more favorable environments. We are talking about the Caterpillar D7 Bulldozer, used by several allied countries during WWII, in various configurations.




Caterpillar D7 Bulldozer with hydraulic angledozer LaPlant-Choate
France, August, 1944.

History:

&nbsp; &nbsp; &nbsp; The Caterpillar D7 is a medium bulldozer manufactured by Caterpillar Inc.. The first D7 appeared in 1938. The D7 dozer was the primary earthmover for construction of survivability positions and antitank ditches. It had to be transported by trailer due to its poor mobility.


A veteran Caterpillar D7 still in use...
Indeed, a tough girl !!


&nbsp; &nbsp; &nbsp; During WW II crawler tractor / bulldozers were used by Allied military for combat construction in Europe, Asia, in the Pacific, literally all over the world.


Heavy Tractor, M1 Caterpillar D7
&nbsp;818th Engineer Aviation Battalion in France - 1944



Finnish D7 in Winter War. Notice the modified blade
Thanks for the pic, Mikko Heikkinen!!

&nbsp; &nbsp; &nbsp;They also served as prime movers for artillery, and for a multitude of other tasks.


155mm M1 Long Tom towed by standard Caterpillar tractor prime mover
during the Tunisia Campaign, 1942-43.

&nbsp; &nbsp;The crawler tractors had unsurpassed capability to move and tow in the muddy jungles of the Pacific islands which made them especially prized by the Americans SeaBees, Marine Corps and Army units in the Pacific Theater.


A Caterpillar D7 dozer gives an LCM(3) a helping hand.



Caterpillar in Guam, 1945



Marine's bulldozer with 3 tones cammo - Iwo Jima, 1945

&nbsp; &nbsp; &nbsp; When equipped with a bulldozer blade, they could level ground for roads and airfields as well as clear debris, construct fortifications and much more.


Caterpillar D7 armoured cleaning the road.
The King Tiger is not too heavy task for this girl!!



Caterpillar D7 hydraulic blade in Gibraltar
building an airfield with a steamroller






Seabee Caterpillar working in airfield at 
Admiralty Islands



Caterpillar D7 Bulldozer with hydraulic angledozer LaPlant-Choate
under maintenance..


Caterpillar D7 described:

&nbsp; &nbsp; &nbsp; &nbsp;The D7 was a big machine 4.114 mm long and 2.539 mm wide without any attachments), but it was also a phenomenal worker_ Fitted with Cat's own model D-8800, 4 cylinder, 80 horsepower, 13.617 cc &nbsp;liquid cooled diesel engine, it had a maximum drawbar pull over 11.500 kg.



&nbsp; &nbsp; &nbsp; With six speeds forward, four in reverse, it could work equally well in either direction. They can be fitted with a LeTourneau-type angledozer on which the blade could be manually adjusted to cut right or left, or to doze straight ahead. The power control unit can be front mounted, but. still relied on cables to raise the blade, A Hyster D7N 15 tons winch can be mounted at the rear, Weighing 14.400 kg, the D7 could tow loads exceeding 11.500 kg.





Caterpillar D7 Bulldozer variants (WWII era):

D7 7M series, manufactured 1940-1944, approx 10,000 produced. D8800 engine, 74 inch track gauge (1.880mm)
D7A 1T1001 series, manufactured 1943, 138 produced. Armor plated 7M with twin hydraulic cylinders, rear mounted Hyster D7N winch
D7 3T series, manufactured 1944-1955, over 28,000 produced
D7 4T series, manufactured 1944-1945
D7 6T series, manufactured 1945


&nbsp; &nbsp; &nbsp; During WW II, the D7 was one of the bulldozers collectively known as "Tractor, Heavy, M1." Equivalent tractors were produced during WW II by Allis-Chalmers Co. (Model HD10W, G-98) and International Harvester Co. (Model TD18, G-101). About one thousand Caterpillar D7s were also produced by American Car &amp; Foundry under license when WW II military orders exceeded Caterpillar's capacity.

&nbsp; &nbsp; &nbsp; See the movie below: a Caterpillar D7 in action:




Specs:








Caterpillar D7 bulldozer
TypeTracked medium tractor (civil)
Crawler heavy tractor M1 (military)
Place&nbsp;of&nbsp;originUnited States
Service history
In&nbsp;service1911-1945
Used&nbsp;byAllies
WarsWWII, Korea, Vietnan
Production history
DesignerCaterpillar Inc.
Designed1938 &nbsp;
ManufacturerCaterpillar Inc.- American Car &amp; Foundry
Produced1938 -&nbsp;
Number&nbsp;built+ 39.000
Variantssee text
Specifications&nbsp;
Weight14.400 Kg
Length
Widht
Height4.114 mm
2.539 mm
2.40m
Crew1


Engine

TransmissionCat D8800 Diesel, 60/90 HP - 4 cyl. - 13.617 cc.
6 gears fwd. x 4 rev.
Speed forw.18 Km/h
Speed rev.11,2 Km/h
Fuel tank460 liters
Fuel consum.
Traction cap.22 liters/ hour
11.500 kg.



The kit:

&nbsp; &nbsp; &nbsp; Thank the Gods, today we are very well served in terms of tractors. Two Companies (MiniArt and Mirror) inject in plastic various versions of these vehicles, with very reasonable prices, in 1/35 scale:








&nbsp; &nbsp; &nbsp;&nbsp;As a matter of choice of version, I chose this young lady: Caterpillar D7 Bulldozer - Hydraulic blade version.





&nbsp; &nbsp; &nbsp; Let's start...


In my workbench...



Tools, booklet and parts...



&nbsp; &nbsp; &nbsp;&nbsp;Well...Starting at the beginning: by the booklet !! Many parts are very, very small and fragile. but, the worst, impossible to be cleaned without damaging them. The Department of Engineering of Miniart could have put the injection connections in more favorable cleaning places.&nbsp;


Notice the size of parts and the position of connections


&nbsp; &nbsp; &nbsp; Another criticism: parts that could perfectly be merged into larger pieces without diminishing the detail. Small and ridiculous pieces that add up to nothing in detail, but tired of building and cleaning. In summary, an annoying kit.


The sparkplugs glued without cleaning. i'll do that in position
Notice the part pinted by lower arrow: Why not casting in the engine block??


&nbsp; &nbsp; &nbsp;&nbsp;After the spark plugs glued, I was able to clean them ...I used glue-welder to smooth the surface of the spark plugs...


Spark plugs cleaned, at last...


&nbsp; &nbsp; &nbsp; And suffering (useless, in my opinion ...) continues. The piece that was in this position simply disappeared when cut. A lubrication plug that could have been cast in the big part WITHOUT ANY DETAILS LOST !!!


Part made in styrene to substitute the missing plug!!
Ridiculous!!!


&nbsp; &nbsp; &nbsp;&nbsp;Another oil plug. Why this part was made in separate??  Why?? They look the infamous old Dragons 3x1 &nbsp;kits&nbsp;that had thousands of little (useless and invisible...) pieces and not sold in stores. Modeling is a hobby, Lady Miniart ... not a self-flagellation session !!! IMHO!!!


Notice the size and BIG DETAIL of this oil plug...



And glued in place... &nbsp;Why?? &nbsp;Why?


&nbsp; &nbsp; &nbsp; &nbsp;After 2 hours of pain, I build this:



&nbsp; &nbsp; &nbsp; &nbsp;Well,...After this outburst, we will continue the engine constryção. I admit that is very detailed, but at least about 10 or 20 of these parts could simply be casted in the engine block, without problems. Again, IMHO!


The metal part is there to replace a small parts that flies off
and was not found ... Carpet monster strike back!!



More sub-assembles...



Well...the engine is almost there...


&nbsp; &nbsp; &nbsp; It's definitely not a kit for beginners. The fragile parts and brittle plastic lead you to the madness. It's unpleasant to write that, but this kit did not provide to me pleasure, so far ... To me modeling is a nice hobby and not an irritation and suffering exercise. But let's go ahead !!!


&nbsp; &nbsp; &nbsp;And the Saga continues....


The engine in the chassis...



Other side...


&nbsp; &nbsp; &nbsp; Another piece with injection marks in its most fragile portion. The best option is to replace the portion with Plastruct:


Impossible clean the injection marks in
this part...


&nbsp; &nbsp; &nbsp; Control levers and cables. A pity that this detailing will disappear beneath the cabin floor...


Details...amazing details...but...



...Plastic is extremely brittle and fragile!!



All details disappearing ... Frustrating !!



The suspensions: sub-assemblie in position



The suspensions: sub-assemblies in position


&nbsp; &nbsp; &nbsp;&nbsp;And now, the nightmare: LBL tracks. I hate LBL tracks !!! And the worst is: the kit supplies the exact amount of parts. NO SPARE PARTS!!! &nbsp;If you break or lose a little bit, you're lost !! 


First of all, removing the small pieces from the trees ...
I hate LBL tracks!!!



Cleaning the little parts!!!
DO NOT BREAK OR LOSE none of these little pieces !!!



Beware!!!There are parts left and right ... Do not mix !!



&nbsp; &nbsp; &nbsp; To build the tracks, forget the instruction manual !! I followed this method: I glued the pins in the half-segments of each link and then I inserted and glued the other half-segment, building the track, but without the pads.



Pins glued in the half-segments...&nbsp;



...and the &nbsp;other&nbsp;half-segment glued in the tip of the pin.



The tracks in position. Still moveable...



The two sets buit.

Now, glue the pads... Again, these parts are in EXACT NUMBER!! &nbsp;No spare!!


The tracks done: Total time spent with this step; 4 hours!!


&nbsp; &nbsp; &nbsp; After the track's nightmare, the building is a piece of cake!!&nbsp;&nbsp;


Hydraulic pistons of blade



The tractor's body almost complete !!!






Suspensions in position. I usually paint the whole set ...
Blade under construction...




&nbsp; &nbsp; &nbsp;And, finally, the final assemble; blade in position. You can keep the set mobile, but I do not like it. I fixed the blade in the linear working position.


















&nbsp; &nbsp; &nbsp;Next step: painting!!!


The girl is big!!!



&nbsp; &nbsp; &nbsp; Again, my girl will be Canadian!!













Olive-drab !!



...and Future, to prevent silvering...



Decals...

&nbsp;









Starting details...

&nbsp;








&nbsp; &nbsp; &nbsp; Final details:


Headlights with bijoux details...



PVA glue in the interior of headlights...



New reflectors...



The original lense in the left headlight..
The right one in process...



Done!!


&nbsp; &nbsp; &nbsp;&nbsp;And the new Canadian Girl was ready. Caterpillar D7 Bulldozer (hydraulic blade version)  in duties with Royal Engineers Battalion, 2nd Canadian Corps, working in Falaise, France. August, 1944.


Caterpillar D7 Bulldozer (hydraulic blade version)
Royal Engineers Battalion, 2nd Canadian Corps
&nbsp;Falaise, France. August, 1944.








Caterpillar D7 Bulldozer - left side








Caterpillar D7 Bulldozer - right side

&nbsp;












Caterpillar D7 Bulldozer with Kojak and Rover, the dog.

&nbsp;



M10 Wolverine GMC&nbsp;and Caterpillar D7 Bulldozer
in size comparison

&nbsp;


Caterpillar D7 Bulldozer (hydraulic blade version)
Royal Engineers Battalion, 2nd Canadian Corps
Falaise, France. August, 1944.


Thanks for following, Gents !!