Bed rust repairs

[yungupgrade]

My short bed has pretty bad rust. I've been slowly taking my angle grinder to the rust spots to see what's salvageable or not. The drivers side is mostly salvageable besides the fender corner but the passenger side seems like a lost cause. I do know the bed fenders are for sale on eBay but I have no welding experience. Now I could definitely pay the money for the parts but what metal would I need for the "odd" spots? I would prefer not to sink a ton of money into just the bed. Not sure if it would be cheaper to buy a rust free bed, but if it is I'll definitely consider it. Any advice?

[ghetdjc320]

The replacement bedside panels will need to solid metal to weld to. It does not look like that would be a good option for you rig. I would be curious to know how the underside looks as well and in how many places the rust has eaten clear through the metal. Having a shop weld on new metal will probably cost you more than a decent replacement bed. @Pete M is our Comanche bed got to. 
 

Now I don’t recommend this as it’s not a permanent nor a structural way to repair things but you could also sand everything down with 80 grit (using a da sander or similar) to remove all loose scale and paint. You could then use the whole por15 treatment process which starts with an acid based rust killer. I have seen people even use a mesh backer along with several coats of por15 to create an almost fiberglass-like structure to bridge holes in sheet metal. That stuff is quite the product with proper prep work. 

[Pete M]

ouch.  that bed is... toast.    where are you located?

[yungupgrade]

4 hours ago, Pete M said:

ouch.  that bed is... toast.    where are you located?

just sent a PM

[yungupgrade]

4 hours ago, ghetdjc320 said:

The replacement bedside panels will need to solid metal to weld to. It does not look like that would be a good option for you rig. I would be curious to know how the underside looks as well and in how many places the rust has eaten clear through the metal. Having a shop weld on new metal will probably cost you more than a decent replacement bed. @Pete M is our Comanche bed got to. 
 

Now I don’t recommend this as it’s not a permanent nor a structural way to repair things but you could also sand everything down with 80 grit (using a da sander or similar) to remove all loose scale and paint. You could then use the whole por15 treatment process which starts with an acid based rust killer. I have seen people even use a mesh backer along with several coats of por15 to create an almost fiberglass-like structure to bridge holes in sheet metal. That stuff is quite the product with proper prep work. 

Ironically the underside is nowhere near as bad as the wheel wheels. Pretty crusty, but not rotting away like that. Interestingly I have also found no evidence of frame rot given how rusty the bed is. I've stabbed every inch of that frame with a screwdriver as hard as I can and no metal has caved. 

 

I do plan to use POR15, but I was going to use it on the frame, prep it like you said and try to do the inside of the frame as well.