[dsraven]

I wax and grease remover the parts first, then I use 80 grit to remove paint where needed. then do hammer and dolly work and then once down to bare steel and you get it as straight as you like you really should epoxy prime the metal before adding any filler. filler is a porous material that is prone to holding moisture so you don't really want that against the steel. epoxy seals the steel from outside elements and seals any old paint so it won't react with any new products applied over top, then a skim of filler as needed and appropriate sanding, then some high build primer, usually a different color than the epoxy so you can see when you get close to sanding through the high build and also a type that is good to use direct to metal in case you have sanded through the epoxy, and then block sanding-more high build etc, sealer and paint. if you are like me and those parts will sit for a bit before paint and assembly then I usually give them a shot of epoxy again (another color than the high build for the same reasons) to seal them since the high build is not a sealer and can also hold moisture, oily fingerprints etc. epoxy these days is a lot more easily sanded than days past, especially if wet sanded and you choose the right brand, so that is less of a concern. if it will be awhile sitting in epoxy the stuff also hardens up so the sandpaper doesn't gum up either, especially if wet sanded. the epoxy seals it so you can handle the parts for mock up etc. I use the durablock sanding blocks for the finishing sometimes as they are hard but flexible. I use a long board sandpaper strip stapled to a piece of plywood for getting panels straight on rough in because I find the foam covered long boards can have too much "give" in them so they conform to the panel too much. a hard straight piece of wood only hits the high spots for getting things straight and true to start with. the durablocks will conform to a curved panel and still only take the high spots off as long as you don't apply too much pressure. part of the process is to apply less pressure so your paper only takes off the high spots. sometimes for those small areas or corners I will use an eraser from the office as it is also hard but flexible and doesn't absorb water when wet sanding. also, if wet sanding, change the water lots so you don't get a stray piece of git or dirt on your paper from the bottom of the bucket. some detailing places carry a bucket screen that fits in the bottom of a 5 gallon pain to keep sanding blocks from hitting the bottom and picking up contaminants. when changing paper grit change the water for the same reason otherwise you can pick up grit mixed in the water from the courser paper. when doing some rough bodywork, in the hammer and dolly stage, a huge felt tip marker from the dollar store can be an asset. just rub the marker on the panel and when you do a quick sand with the hard sanding board to find the high spots you will easily see where the paper has taken off the marker on the peaks. a shrinking disc can be your friend at the end of the hammer and dolly stage, it heats up the high spot, you quench that with water right away, and the high spots shrink down to be flat like the surrounding material. some guys have had luck using an old laundry iron for the same purpose. the metal just needs to be hot enough to make steam when a wet rag is applied. others will use a torch but it is an art then and requires practice so you don't go too far and cause more headaches and work. if you have sandblasted parts they will need to be wax and grease remover treated, then the parts should be sanded to remove the blasting profile. even if they look good the profile can be like a mountain range if you look close. if you simply shoot epoxy on them and store them for later you can end up with the peaks showing through and the parts can be rusty when you come back for them. one of those vixen body files works pretty good to take the basic high spots off the straight panels, since sandpaper goes flat pretty quick on bare steel. a flap disc also works but then it also leaves a profile to deal with. a vicious circle.
anyway, that was long winded so I will stop ranting now. keep up the good work and post those pics. it keeps us interested and motivated on our own projects.