Tech: Scratch build References

Tech: Scratch build References (using a scale model to build 1:1 blueprints)

After purchasing a nice rolling chassis with 4 banger motor and open car cowl, I was ready to build my Hotrod.


I finally decided that a 28 29 roadster pickup was the way to go. I would just build the back half of the cab and a couple of doors.


One problem, I didn’t have any blueprints or know anybody who had a car I could use to take measurements from.

I came up with a solution that would get me close enough. I went to a hobby store and bought a scale model of the car I wanted to build. I would take measurements from the model and scale it up to create my own blueprint for the build.

Tools needed: calculator, ruler, calipers, & a decent scale model.


Carefully measure the pieces need for your drawing. Multiply the your measurement by the scale your model was built to. In my case the Revel model kit I bought was a 1:25 scale. So I multiplied everything by 25.


This method will get you close to the outside dimensions You will still need to account for flanges and internal details not present on the scale model. The kit I bought came with a separate frame, bed, & 2 cabs.

Here is a PDF file of the drawing I did using this method
View attachment 28-29_ROADSTER_PICKUP.pdf

 

That is different and I LIKE IT - keep us posted on the progress.

 

This thread will give you photos of the little details, and tips on fabrication.
http://www.jalopyjournal.com/forum/showthread.php?t=299603
Don't expect to do as good as Neal on your first try.

 

Thanks. I'm not worried about the doing the metal work. Vintage tin is real scarce here in New York State. I just couldn't find any plans or drawings for the cab. I still need to find one locally so I can see how the door jamb goes together. The drawing I was able to put together should get me real close.

 

Remember, those scale models are not real true to scale. If something looks off when you start building, follow your eye.

I had that same kit out the other day comparing the cowl area to a vintage 28 sedan kit, niether one matches the other and both look "off" from the real steel PU and sedan in my garage.

 

thanks Tman. It helps that I already have a cowl and frame as a reference. I'm hoping using those and the model i can make it come together. the back of that cab is square and that should help.

 

Now that's what I call "reverse engineering!"

Anyone want to pound out a belly tank based on measurements from that old P-47 model lying in the basement...

 

your body first and your eye second. make it fit you. model A's are a little short on leg room

 

I'm 6'-4" so there will have to be some stretch. I was thinking a few inches in the doors and a few in the cab.

 

I admire your industriousness. 1/25 is quite a scale up, but I gather you're just looking for general dimensions. Good luck on your build.

 

It would pay to do some research on the model kit you are going to scale up. Although the Revell kit you used is pretty good many of the earlier kits are VERY inaccurate. Take for instance the old AMT 32 5 window. That bares little resemblance to the real car. I saw some guy use one the same way for a 1:1 project, the car looked like an MG!
Doc.

 

I was just looking for general dimensions. the back half of that cab is pretty square. I just needed some reference point to work from. Basically I'm just making a 3 sided box with some curvature on the bottom. same for the doors.

 

I extrapolated measurements from photographs when building the cowl mold for my Bantam. Once you have a known measurement, the rest is just simple math.


Flatman

 

I will have to keep that in mind. I have more than a few pics of 28-29' RPU's.
thanks

 

Good idea - but you could take it a step further with the help of your internet hamb buddies.
Post some drawings and label the dimensions a, b, c etc. then ask if anyone can check the dimensions against their real one - it only takes a few minutes and can be very helpful.
I've taken measurements from my car for people before now.
Mart.

 

thanks Mart. I know I could count on my Hamb Brothers to help me out. when I start on the doors I Will need some good photos of the jamb & the inside of the door. It would be cool if I could get a picture without the door skin attached.

 

I used the same model and some dimensions from the HAMB to come up with the blue and the green models in the image. I didn't follow up with adding any other details yet but plan to at some time. I would also like to do up a 28-29 closed cab as well.

 

oldtin,
cool. what software did you use to create that? I have an accurate model of a T frame.

 

I work in Unigraphics, thats where the posted image is from. I also dabble with Catia, and occasionally mess with autocad.