1/16 Scale Ford "Quad" Field Artillery Tractor Design and Build

[darter]

I do not count studs as I do not count rivets.
The heads look great and uncluttered.
If it looks right then it is right.
So I still count 24.
Great work.

[missileer]

Dave,
I think your current design looks fantastic. Since I have never worked on or studied the drive trains of heavy duty equipment of either Ford or Chevy, I would not notice the difference. I would bet that a good percentage of the modelers who will build this model are in the same boat. I just want to build it, because of the detailed, complexity and size of the model. It will be a show stopper, regardless of who's drive train you use! That's my two cents.

John

[whulsey]

Dave, have you seen this photo of one under restoration in Australia? Shows the towing set up fairly well.

The V8 you show is a later model with the more conventional mount distributor. The WW2 type would have still been the 'crab' type mounted on the front of engine behind the belts.

[airdave]

Distributor on my engine (if I were to install one, which I will not) is in the front
thats why I directed the wires that way...but mine is nothing more than a stylized version of flathead.
Thats also why I didn't bother too much about the exact number of head bolts.
Don't read so much into it...its as good as its gonna get! lol

...
Having said that, I am now being anal about the Tow setup in the rear.
(Mainly because this is a more obvious component once the model is built).

The issue is these Quads are the 4x4 short chassis version of the CMP Truck
built both by Chevy and Ford in Canada.
As such, they incorporate a very similar overall design, but with many different components and sub-assembly designs.
The Chevrolet version, for example, uses a straight 6 Chevy engine and Chevrolet Axles and Differentials.
Whereas the Ford has the flathead V8 and different style Axle castings.

Not only are there two different manufacturer designs, but body styles evolved and there were many changes over the course of the War and after.

Both Chev and Ford designs have a cable winch system driven off the main drivetrain, but the cable pulley and guide assemblies differ between body types and manufacturers.
So too, does the rear Towing Hitch mount.

My Gun Tractor is intended to be a Ford design since I preferred the early Ford body style (more like the British Morris C8) and the interesting Ford Differential housings.
Unfortunately my original (model) design for the back end of the frame
was based on some reference photos that turned out to be a Chevrolet Quad.

Like this:


And my model:


Its funny...when this was first suggested to me (that my Ford had Chevy parts)
I had just photographed a Chev Gun Tractor locally, and it had a radically different setup.
I thought for sure I had the correct design.

Late model wide body Chevrolet Gun Tractor:



Anyway, I have since discovered, that the Ford setup...at least on earlier Fords...looked more like this.
In fact, exactly like this:


So, now I have to go about modifying my design.
As I said to someone else, I have no problem modifying my model design.
In fact I prefer this design with its larger support end brackets that almost look like "bumperettes".

My problem is with modifying my test build...cutting off parts does a lot of paper damage.
I don't want to rebuild the entire frame at this point.
But I don't know how easily i can cut off the wrong parts and replace them.

Thats my dilemma, and where the project stands at the moment.
Stay tuned for a report!


...

[darter]

Dave, if you're happy with a stylised drive train and happy to leave details such as a distributor, to the builder, then surely you can be happy with a stylised tow hook.
It looks great to me and if a builder wants a different hook then they can make a different hook.
I'm sure that if you were to see these vehicles in use during the war there would be quite a number of variances between them.
So, unless you are portraying a very particular vehicle, who can say what was right.
Your'e doing a brilliant job.

[airdave]

I guess thats my problem...
I was(am) very specific on the type (Ford not Chevy) that I was portraying.
And the Rollers, Cable Guide, Hitch and Spring Mount, and bracketry
are very obvious on the finished scale model.
In fact (unlike the engine) they are an important visual detail (in my opinion).

And if the design I did, is definitely not a Ford type, then I have to change things...just for my own sanity.

I'm okay with redesigning and changing the kit...
I just hope I can cut off the parts and install new parts on my prototype
so as not to have to build another one!

Although, I do agree with you...in the field, someone could have welded a different setup onto the back of this Ford.
Who would complain, as long as it worked?
But until I find a Ford FGT with this same setup, I have to submit to the ones that have pointed it out.

[CharlieC]

Originally Posted by darter

....
I'm sure that if you were to see these vehicles in use during the war there would be quite a number of variances between them.
....

I don't there would have been especially on an artillery towing vehicle. You have to be able to unhitch the gun in the dark without showing any lights. About the only way to do this is endless practice on a hitch which doesn't change between vehicles.

Regards,

Charlie

[airdave]

The Hitch(hook) itself (or its position) is not in question.
Same goes for the Leaf Spring type plate that supports the Hitch Hook.
Those are the same on every vehicle.

Its how that Leaf Spring is suspended between the tail end of the frame rails.
And the various bracketry and plates that go there.

Its also the large rollers for the Tow cable.
I've seen at least three different set ups, with various widths of rollers.

...
Once I get the proper Ford parts figured out, I'll post an update.
If the chassis survives the dissection to receive those parts, I'll post a happier update.

[rickstef]

Dave,

Pardon the question, I am not sure if you mentioned this, but have you contacted any of the museums which might have a Ford version of the truck in their collection, and ask if they would have a digital copy of the field manual for the truck?
Or even the Libary of Congress? Or the Army Heritage Center?

I have in my collection a field manual of the CH-47D, and in there are dimensions and detail drawings, so this might be an idea if you get stuck.

[airdave]

Considering all the vehicles and variants, produced by two different manufacturers over the course of the War...
it would be difficult to have a full manual for every vehicle.
I have a copy of the "Vehicle Data Book - Canadian Army Overseas" produced in 1944 that lists all CMP vehicles in use at that time.
At least 200 vehicles are detailed with their very basic specs along with maintenance and operation information.

Bodies were produced by a separate company.

I have clear photos of both Chevy and Ford chassis that show the differences in the frame attachments.

As I said...I already know what it looks like...I have photos of the Ford chassis.
As I already explained, my original design was based on some photos (one photo in particular) of a Chevrolet chassis.
I made the mistake.
I didn't think to verify that the Ford was different.

My issue is not with redesigning the model...its with altering my test build.
I don't want to rebuild the entire thing (to this point).

...
Museum?...lol There are few Canadian Gun Tractors in Museums around the world,
and once again, there are too many variants.
So to find exactly the right one....

And you have to rule out the Australian versions...they can be quite different.

Most CMPs existing today are in private hands, and I have had better luck dealing directly with their owners on the forums.
But once again, so many variants...

And, as I said, its not an issue of the difference between a Ford and a Chevy.