first, I've searched and read here and many other places in recent months and I've been using epoxy primer (as well as other products) in a number of things with really pleasing results overall. It's what I'm planning to use on the underside of my current project - a 4wd project for weekending on and off road, mountains, beaches (salt!), etc...
the underside has some scattered surface rust (especially along seam areas ..grrr) as well as rust a few places (but not very many) that go in to "frame" rails. There was only one spot that was structurally weak (below the battery). I cut it out and replaced it. Overall I'm doing a LOT of welding on this - plating, gusseting and reinforcing the majority of the unibody structure, removing and adding brackets, etc.... It's not intended to be a work of art, nor is it going to be, but it will be plenty strong enough for what I have in mind. Once I get the majority of the metal work finished, I want to stave off rust expansion for absolutely as long as I can. (I've been working on it a couple months when I have time, and will probably be at it some weeks before "finished") I'm leaning strongly toward...
1. using da with 60 grit, wire wheel and needle scaler (only thing that'll get in to a lot of the corners, etc...) to remove as much of the rust spots and compromised paint that I reasonably can and to rough up the new metal metal surfaces. (don't care about surface imperfections..)
2. use a shop vac and / or compressed to clean out anything in the frame rails / unibody where I have access
3. use pressure washer with clean any heavily oily areas with soap and water
4. drench all of the surfaces with ospho using a garden sprayer and let it sit over night (being somewhat careful not to get much if any into the cavities in the unibody - may temporarily plug the drain / vent holes)
5. pressure wash it
6. spray it down again with ospho and soap, then pressure wash, flush well with water.
7. After it's dry, give the whole mess a couple wet coats of epoxy primer
8. once that's good and dry, do all of the cavities as well as the surfaces with some home brew cavity wax (beeswax, lanolin, rust inhibitors in a mineral spirits base - a variation on a mix that seems to be working really well on some other things so far, and it smells nice too ), and retreat / coat with that ever few years as needed...
am I missing anything? or is there something I can do that will work better for this sort of an application?
Thanks!
the underside has some scattered surface rust (especially along seam areas ..grrr) as well as rust a few places (but not very many) that go in to "frame" rails. There was only one spot that was structurally weak (below the battery). I cut it out and replaced it. Overall I'm doing a LOT of welding on this - plating, gusseting and reinforcing the majority of the unibody structure, removing and adding brackets, etc.... It's not intended to be a work of art, nor is it going to be, but it will be plenty strong enough for what I have in mind. Once I get the majority of the metal work finished, I want to stave off rust expansion for absolutely as long as I can. (I've been working on it a couple months when I have time, and will probably be at it some weeks before "finished") I'm leaning strongly toward...
1. using da with 60 grit, wire wheel and needle scaler (only thing that'll get in to a lot of the corners, etc...) to remove as much of the rust spots and compromised paint that I reasonably can and to rough up the new metal metal surfaces. (don't care about surface imperfections..)
2. use a shop vac and / or compressed to clean out anything in the frame rails / unibody where I have access
3. use pressure washer with clean any heavily oily areas with soap and water
4. drench all of the surfaces with ospho using a garden sprayer and let it sit over night (being somewhat careful not to get much if any into the cavities in the unibody - may temporarily plug the drain / vent holes)
5. pressure wash it
6. spray it down again with ospho and soap, then pressure wash, flush well with water.
7. After it's dry, give the whole mess a couple wet coats of epoxy primer
8. once that's good and dry, do all of the cavities as well as the surfaces with some home brew cavity wax (beeswax, lanolin, rust inhibitors in a mineral spirits base - a variation on a mix that seems to be working really well on some other things so far, and it smells nice too ), and retreat / coat with that ever few years as needed...
am I missing anything? or is there something I can do that will work better for this sort of an application?
Thanks!