Truck spec sheets versus models

[robdebie]

I just had the AMT Peterbilt 359 California Hauler delivered, that I want to use to build the 'Duel' movie truck. In an old FSM article on that subject, the builder extended the frame 3/4". But first I wanted to know what the kit's wheel base is. With the parts still on the runners, I measured ~207 mm (front axle to middle of rear axles), translating into ~204".

I had collected as many Peterbilt spec sheets as possible, so I wanted to see whether 204" made sense. But to my surprise, all wheelbases listed in the spec sheets were smaller. The longest I could find was 192"1/2 for a 351.

So what's happening here? Did AMT come up with the wheelbase themselves? Or are the brochures incomplete? Or is there another explanation?

Rob

Edited May 6, 2023 by robdebie

[Muncie]

For a heavy-duty truck, standard wheelbase is a grain of salt thing. The spec sheet will have a standard wheelbase, but heavy-duty trucks can be ordered with almost any wheelbase in one inch increments. 

The standard wheelbase is for a truck without any options.  Add a sleeper on the order and the wheelbase is increased.

The wheelbase may be a later modification.   When trucks see a few years, they start getting modified for a second or third owner   The pictures in the other thread show a big gap between the cab and the front of the trailer like a sleeper had been removed.

Edited May 6, 2023 by Muncie

[Force]

4 hours ago, robdebie said:

I just had the AMT Peterbilt 359 California Hauler delivered, that I want to use to build the 'Duel' movie truck. In an old FSM article on that subject, the builder extended the frame 3/4". But first I wanted to know what the kit's wheel base is. With the parts still on the runners, I measured ~207 mm (front axle to middle of rear axles), translating into ~204".

I had collected as many Peterbilt spec sheets as possible, so I wanted to see whether 204" made sense. But to my surprise, all wheelbases listed in the spec sheets were smaller. The longest I could find was 192"1/2 for a 351.

So what's happening here? Did AMT come up with the wheelbase themselves? Or are the brochures incomplete? Or is there another explanation?

Rob

Remember that the AMT 359 California Hauler kit is too new for the Duel truck, the truck in the movie was a 1957 281 narrow hood and the cab is slightly different.
I just looked in my "Duel files" and found pictures of a build done by Tim Ahlborn and he did 208 inch wheelbase on his Duel truck, and it looks about right.
The original Duel 281 truck was built as a tanker but with a different trailer than it has in the movie, and after what I have found out it could have been bought new by Union Oil in 1957.
Here is a photo of a Union Oil truck specified like the Duel truck with pretty much the same equipment.

 

Edited May 6, 2023 by Force

[robdebie]

2 hours ago, Force said:

Remember that the AMT 359 California Hauler kit is too new for the Duel truck, the truck in the movie was a 1957 281 narrow hood and the cab is slightly different.
I just looked in my "Duel files" and found pictures of a build done by Tim Ahlborn and he did 208 inch wheelbase on his Duel truck, and it looks about right..

Håkan, thanks for the interesting comment on the cabin. I had read that comment too in one of the build threads here on the forum. It said the old cabin had 'smaller' windows. I compared photos, an maybe the windscreen height should be reduced a bit. Do you know?

Thanks for the wheelbase figure, it seems the kit is in the right balkpark.

Rob

[robdebie]

3 hours ago, Muncie said:

For a heavy-duty truck, standard wheelbase is a grain of salt thing. The spec sheet will have a standard wheelbase, but heavy-duty trucks can be ordered with almost any wheelbase in one inch increments. 

The standard wheelbase is for a truck without any options.  Add a sleeper on the order and the wheelbase is increased.

The wheelbase may be a later modification.   When trucks see a few years, they start getting modified for a second or third owner   The pictures in the other thread show a big gap between the cab and the front of the trailer like a sleeper had been removed.

Steve, thanks, good point about sleepers. I hadn't thought about that.

Rob

[Force]

8 hours ago, robdebie said:

Håkan, thanks for the interesting comment on the cabin. I had read that comment too in one of the build threads here on the forum. It said the old cabin had 'smaller' windows. I compared photos, an maybe the windscreen height should be reduced a bit. Do you know?

Thanks for the wheelbase figure, it seems the kit is in the right balkpark.

Rob

On the pre 1960 351/281 cab wich pretty much was a carry over from the 350 the roof cap is slightly different with less rivets and a drip rail all around it, the rear window is smaller with a slider to cover it, the front windows are smaller than on the post 1960 cab and the dash is different. 
Tim Ahlborn's website is a well of Peterbilt information and here is his spotters guide for the 50's to the 80's.
http://www.timstrucks.com/PB1.html

[robdebie]

10 hours ago, Force said:

On the pre 1960 351/281 cab wich pretty much was a carry over from the 350 the roof cap is slightly different with less rivets and a drip rail all around it, the rear window is smaller with a slider to cover it, the front windows are smaller than on the post 1960 cab and the dash is different. 
Tim Ahlborn's website is a well of Peterbilt information and here is his spotters guide for the 50's to the 80's.
http://www.timstrucks.com/PB1.html

Håkan, thanks for reminding me of that. I made a photo compilation that shows these details clearly.

The solution might be simple: design 3D printed wide rubber windshield gaskets, slightly lower, to be glued inside the kit's windows. And a piece of steel wire to wrap that drip rail all around the cabin.

Rob

 

[robdebie]

Here's the first version of the windshield correction piece. The radius of the pre-1960 windshield corners are much larger, so I decided to start with an insert made to fit the kit windows, and added the rubber gasket on top of that piece. On the top side I left 0.5 mm to create a bit of space to the drip rail.

On the back side I made a recess for the glass.

This should work I think! Comments are welcome though.

Over to the next problem area..

Rob

 

Edited May 7, 2023 by robdebie

[Force]

18 hours ago, robdebie said:

Here's the first version of the windshield correction piece. The radius of the pre-1960 windshield corners are much larger, so I decided to start with an insert made to fit the kit windows, and added the rubber gasket on top of that piece. On the top side I left 0.5 mm to create a bit of space to the drip rail.

On the back side I made a recess for the glass.

This should work I think! Comments are welcome though.

Over to the next problem area..

Rob

 

That would work.
3D printing is da thing as you can do whatever you want.

[robdebie]

21 hours ago, Force said:

That would work.
3D printing is da thing as you can do whatever you want.

Yeah, it almost looks too easy. But still you have to analyse photos, draw it in 3D, and print it, or have it printed in my case.

The parts could be scratchbuilt fairly easy too, one could make the rubber gasket with (for example) two diameters of lead wire .

Rob

Edited May 9, 2023 by robdebie

[Force]

Yes that's right, either that or use half round Evergreen styrene strips where you soften the corners with liquid glue, bend to shape when soft and after it dried put on the model.