New 1963 Shasta Deluxe Airflyte Member

I am sure others will chime in, but any interior wood damage indicates more extensive damage under the skins. You can lift the lower skins but not remove to check for floor sill rot and you could replace if needed. Most have a degree of rot. Any rot will structurally compromise the integrity which could cause failure. Any pics?

Your trailer should be fine stored inside. The problems with vintage trailers occur when they are on the road and out in the weather.

I'm curious about the angle iron you described. If it is below the sills, not original. The front, rear and side skins should be lifted so that you can inspect the wood. Any soft spots need repair before taking it on the road. Edge trim, awning rail, roof protrusions, doors and windows should be re-puttied.

Birch ply is available, you just have to search for it. Many of us use shellac as a finish.

We are always happy to help.

Doorskins can sometimes be found at local lumber yards. They are 1/8 and usually have nice patterns.

Yes, my eBook is here: vintagetrailerrepairmanual.weebly.com/ It doesn't address add ons like the angle iron seems to be, tho. Lots of good info and photos. It is electronic. Email help and questions always welcome.

Also try Larry's site: cannedhamtrailers.com/ He has many videos on repairing vintage trailers.

Peter makes a good point about the paneling.  Red oak or white oak offers a good match for the grain in ash paneling. I don't remember which one tho. Do a search on red or white oak panels in the search bar on VTT and see what comes up.

I would also call around to lumber yards to find the paneling.  It's a little more, but the quality could be better.  Somewhere on our site is a thread about paneling sources.  I think it focuses on birch, but if they have birch, they problaby have one of the oaks I previously mentioned.

Also, in regards to the unusual angle iron on the sides, It could act like a catch for rain water dripping down along the sides and then holding it under the skirt board that runs under the sides of the trailer. That could accelerate wood root.  That's just a guess.  If you can slide a piece of paper down between the skin and the back side of that angle iron, I would expect water to get in.  You are in California and some famous old boy band wrote a song about how much it rains in California.  That helps. Your trailer is stored in doors, so  it's protected, but still I would be curious as to what you would find once the skins were removed as Vikx suggested. 

Going underneath and sticking an ice pick or an awl into the wood that's covered by the angle iron might tell you the condition of the wood or just wait until you get to the point of pulling the skins.

I once had a Scotsman that had angle iron added on the front at the bottom of the front wall, and the water had cascaded down the front from above traveling under the angle iron and then rotted the wood severely underneath. That angle iron had been added for wall support by some PO, but it made things worse by feeding the rot. I tried looking for the thread, but I can't find it. It had photos in it.

Rod

Thanks for the advice. I won't buy any paneling without taking a sample that doesn't have shellac. I am familiar with white and red oak. I did find some soft spots on the sill, and it makes sense that the angle iron collects water. Not sure why they would add the iron. I will have to learn how to lift the skin as I don't see screws on the bottom yet and am thinking it might be hard with the iron in the way. I will want to remove the angle iron permanently eventually, but it won't be in rain with angle iron or on the highway until I can see the sill condition.

Did you ever decide what to do for interior stain?. I wouldn't be able to say that it would work for you, but I use amber shellac for my birch panels
It's off the shelf and I actually use a cup gun and spray mine. Very similar match without going through all the trouble with using alcohol based dies to mix with shellac. Very low pressure, 40psi.