utahiker
I purchased a new Retro Jr. 509. Does anyone know what the structure is behind the exterior metal? I'd like to add a roof rack and (suv type) ARB retractable awning. I want the roof rack for mounting solar panels.
I also might need to try to fix a fender that's not level (off camber). I'm hoping the dealer I purchased it from will get manufacturer warranty approval to fix it. I can't tell why it's off without know what's behind the siding. 

Fender Right (bad) 1.JPG Fender Right (bad) 3.jpg 
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Mic Tod
As far as I know (u should ck with Riverside at http://www.riversidervs.net/) all their trailers are made with Aluminum tubular framing - like a roll cage.  At least our 177SE is.  Dunno about the 509 but I think it very likely the same.  Gone are the days of 2"x2" wood frames & staple construction.   These trailers are strong and lightweight
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Toothless509jr
Did you ever put a roofrack on your trailer? im looking to do it with mine so i can put up an awning and solar shower
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hiteck
I'm interested in this as well. I just emailed Riverside RV, and am hoping for a reply. I'll reply here if I get a response from Riverside.
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2ty
Retro 509.jpg This should give you some idea of the tube construction, it's all I have without skin.
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hiteck
Thanks for the pic 2ty!

So it appears to really just be a couple hoops for the sides with a flat bottom, supports around the doors, galley and under storage. I would assume there are a few more pieces of aluminum for the roof and in the front.
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TravelerGuy
Hi Utahiker,
This photo is of a 177, but maybe yours is similar on top...
Retro177Construction_1.jpg 
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