You don't really need plans. A couple of photos or a fair idea of how it should look. You can eye ball the dimensions to clear the car and fit your space.
Along with I's and H's Iwould get some channel, angle and rod, to fit your scale. Of coarse sheet goods in the correct thickness.
I don't use plans of any sort in my scratch building, just try to image how ''they'' would build it, and have at it.
Click on the "footprint" and it gives you the size, in inches. You can take it from there, for a scratch build.
https://www.walthers.com/cornerstone-series-r-detail-parts-wood-chip-car-loader
Mike.
My You Tube
If you know the Walthers model number, you may be able to find one by searching online, as hobby shop inventories may contain one or two long after Walthers runs out.
You might also contact Walthers and see if they would send you an instruction sheet. They keep many of these on computers, so they might be able to pull up a copy and email it to you.
It takes an iron man to play with a toy iron horse.
I am new to the forum and after a 25 year hiatus, I started to build an HO layout. I very much interested in scratch building a wood chip loader as an extension of large wood industry plant. Walther's detail kit would have been ideal, but is no longer available. While I have several kits on my layout I really enjoy scratch building. Looking to build this out of scale I and H beams, with cat walk, etc. I would appreciate any direction or insight on some plans. Thank you in advance.