Frame Rust

That's about what mine used to look like. I scaled everything off of it with a hammer, chisel, putty knife several.years ago and it really wasn't a problem. Frame was just all rust color. This summer I scaled it again and brushed it good then sprayed it with some Rustoleum rust killer paint then gloss black. If I could do it over again i'd go with flat black. Mine has pitting in places but I doubt it will ever will break through.

 

A half dozen spray cans of primer and paint, a hammer, chisel, & wire brush is about as cheap as it gets. Of course you can spend $600-$1,000 or more having someone else sandblast it and paint.

 

And I thought my 35 year old frame was in bad shape. And it had a water tank on it for most of its life.

You got a few options. Most expensive would be new rails (KW quoted me $9k Canadian for 1 undrilled rail). Not likely at that point though yet.
You could clean it up with a sandblaster or wire brush cup on an angle grinder and see how it looks. If it still has lots of uncorroded base metal you'll probably be ok. A frame rail insert could also be built and installed behind the rusted section. I got a quote from a steel shop to make me insert rails out of 1/4" thick QT100 and it worked out to cost about $50 per foot. Just gotta make sure you cut the ends at 45 degrees and have them cover an additional foot or 2 onto a good portion of the frame. Also bolt them in, don't weld if you go that route.

 

Your fine.
It always looks worse then it is.
Like said , neddle scale it then sand blast and paint. It's going to have some pits and divits but mostly is superficial and would have to be way worse then that to make it structally unsafe.
Frames are perty thick 3/8 inch is common.

 

go to a local paint shop and ask about frame paint.( I will get the name of it tomorrow) it aint cheap $100 gal. you can brush it on or spray it on. it will stop rust in its tracks. I have a 16 yr old truck that I painted with it. still looks great. but I also blast beaded it before I did it.

 

at the left side in the pic,is that a crack?

 

looks like it is just scale rust under that bracket.

 

Chassis Saver is what I got, brush clean and spray is what I did to my 55 chevy truck frame. Set out in the open for 4 years and still looked great.