DIY rust repair on lift gate

[Spook50]

Okay first of all, if it doesn't work I'll just be taking it to my body shop to have them do it up right. As of now I don't think the rust is so bad that I wouldn't be able to do it myself. On the bottom left corner of the window there's an area of rust that has caused the (original) paint to bubble up and looks like it may have gotten down into the sheet metal a bit. It's slowly crept almost to the bottom of the lift gate and as rusty water drips down it's beginning to discolor the paint on my tailgate (which had some rust repair and a repaint done about 4 or 5 years ago; outstanding work BTW). What I'd like to do is first go to a paint or body shop and get a good epoxy based primer, and then get a color matched mix of paint that will match the current paint color as close as possible, and then a good quality clearcoat to seal and protect it all. Now, my issue is that I'll most likely need something rattlecan based. If I have my compressor by then, I've got an older Craftsman paint gun that's never been used (dad bought it about 15 or so years ago, never used it, and gave it to me when I moved out).
Anyway, my plan is to remove the liftgate from the truck, remove the window and strip the liftgate of all hardware and components like the washer tubing, wiper and motor, etc. Then I'm hoping I can just wirewheel the rusted areas down or, if it's bad, use my grinder with a less agressive flapper wheel to take it down to bare metal. If I have to, I'll use a small amount of body filler to level the sheet metal off and then sand it down to a uniform surface. Once that's done and cleaned, hit it with an epoxy primer, a couple coats of paint, block sand and polish like crazy, with extra coats of paint and polishing if need be, and then several coats of clear and a ton of polishing to get it all uniform. Blending with the existing paint that I don't take off will of course be a challenge, but I'm willing to try my luck.

I do have several questions though since this will be my first attempt at any body work at home.

1) If I need body filler, what's the best I can buy? It'd be only a small amount, so price (hopefully) isn't an issue as long as I can buy small quantities. Ideally I'd love to have it filled by plasma spraying, but I don't think that'll be an option for me.
2) Would one coat of primer be sufficient if it's an epoxy base?
3) Is it advisable to do any prep work aside from cleaning between the primer and paint coats? Sanding, polishing, etc.
4) How many coats of paint would be recommended?
5) Same question as #3 only for between paint and clear coats
6) Is there a maximum number of coats recommended for clear? I'd like to put several on for maximum protection, but not so much that I just end up wasting it.

 

[lathamb]

Rage is good. Or bondo.
The amount of primer depends on the surface prep. Put a guide coat (light coat of spray pant) over the primer and sand with 400-600 grit till smooth. This makes all your low spots visible. If metal comes through before its smooth, spray more primer.
If you sand your primer smooth, there is no other prep needed before paint (except cleaning). Just make sure the primer is good and cured before you sand.
We usually sprayed 2-3 coats of color till covered and then 3 coats of clear. No prep between color and clear. You should spray the clear after the color is no longer tacky, but don't wait too long. The solvent in the clear will make the clear bond with the color.
The whole key to the paint adhering is the surface prep. There should be no "shine" on any surface you are filling or painting. The paint won't stick. A good way to clean the shine off the rest of the gate is red scotch brite and comet bathroom cleaner with water. I'd scuff the entire tail gate, paint the repair areas, and re-clear the whole thing.

 

[vixentd]

1. After washing the tailgate with soap, make sure to wipe the entire tailgate down with a degreaser or wax remover. It will stop any fish eye.
2. If you have any pin holes then you must use a waterproof bondo. Evercoat short strand fiberglass, other wise the moisture will bleed through the holes and bubble the paint.
It sands a little harder than regular bondo.
3. When you have put the bondo on then sand and coat with a top coating, icing in the trade, which is a bondo that flows without any pinhole bubbles.

 

[Spook50]

Great advice guys. Thanks for the input.

Is there a recommended "base" of body filler for the longest lasting without deterioration? Like lead or aluminum based?

Edit: just found a fiberglass based Bondo that uses 1/2" strands of fiberglass. Looks like it should work pretty well if there's any filling needed. Still hoping to not need it at all though.

 

[TRAIL TAILOR]

Spook, I just did quite a bit of body work on my 60.. I have used Evercoat products for years and they hold up very well. I like to use Rage or Rage Gold for my fillers.. I have used the TigerHair (fiberglass)before and works very well, it can be used with or without fiberglass matting.

Clean area with degreaser prior to filler, before primer, and between all coats is my advice.

I used two coats of epoxy primer prior to paint. But, pay attention to the flash times and also the length of time that the primer may sit before paint is applied and how long before you have to "scuff" if you let it sit too long.

I recently used BC/CC and used 2 coats basecoat and 2 coats clearcoat.. Depends on your final color and primer combo.. stay light to light and dark to dark is my policy.

If you are not needing to fill in a large area.. I would use a standard filler without fiberglass personally.

Make sure you knead the hardener tube before mixing. I can't stress this enough. Also, just because you add more hardener DOES NOT mean it will harden FASTER, Actually in most cases will cause the filler to not set and stay soft.

Hope this helps you out.

J

EDIT: Clean area with degreaser prior to filler, before primer, AND USE A TACK CLOTH between all coats is my advice.

 

[Spook50]

Spook, I just did quite a bit of body work on my 60.. I have used Evercoat products for years and they hold up very well. I like to use Rage or Rage Gold for my fillers.. I have used the TigerHair (fiberglass)before and works very well, it can be used with or without fiberglass matting.

Clean area with degreaser prior to filler, before primer, and between all coats is my advice.

I used two coats of epoxy primer prior to paint. But, pay attention to the flash times and also the length of time that the primer may sit before paint is applied and how long before you have to "scuff" if you let it sit too long.

I recently used BC/CC and used 2 coats basecoat and 2 coats clearcoat.. Depends on your final color and primer combo.. stay light to light and dark to dark is my policy.

If you are not needing to fill in a large area.. I would use a standard filler without fiberglass personally.

Make sure you knead the hardener tube before mixing. I can't stress this enough. Also, just because you add more hardener DOES NOT mean it will harden FASTER, Actually in most cases will cause the filler to not set and stay soft.

Hope this helps you out.

J

EDIT: Clean area with degreaser prior to filler, before primer, AND USE A TACK CLOTH between all coats is my advice.

That sounds like a good plan of attack. I've never worked with body filler or detailing any sheet metal work, so this will be a new experience for me in pretty much all aspects. I'm hoping I can use that old spray gun I have to do the job, but just in case I can't, is there anything to keep in mind if I try the rattlecan route to make it look as good as possible?

 

[TRAIL TAILOR]

Spook, If you rattle can the OEM paint.. Make sure you use long and steady passes.. I'd stay around a 50% overlap per pass and be patient until it is completely covered and all tiger-striping is gone..

Also, any of the paint stores that mix paint in a rattle can have the " automotive fan nozzles" for the spray cans. It lays down much smoother.

I am in the middle of nowhere so I ordered my rattle can through https://www.carpaintonline.com/MajorcarpaintManufactures_000161Highsolidsurethaneclear_78_p.html

Was a perfect OEM match to my BC/CC.

Take your time ad be patient.

 

[Spook50]

Spook, If you rattle can the OEM paint.. Make sure you use long and steady passes.. I'd stay around a 50% overlap per pass and be patient until it is completely covered and all tiger-striping is gone..

Also, any of the paint stores that mix paint in a rattle can have the " automotive fan nozzles" for the spray cans. It lays down much smoother.

I am in the middle of nowhere so I ordered my rattle can through https://www.carpaintonline.com/MajorcarpaintManufactures_000161Highsolidsurethaneclear_78_p.html

Was a perfect OEM match to my BC/CC.

Take your time ad be patient.

Yeah my only real qualm is making sure I can make the paint look good and have a good match to the surrounding area on the truck. And of course make sure I have all-over coverage so as to avoid any future rust issues. It took 21 years for this blemish to start barely showing up, so another 20 or so years would be great. It'd be so much easier if my paint was factory fresh, but with as long as it's spent parked outside in all conditions, I'm going to try to find a shop that can do a dead-on color match (as opposed to just matching the OEM color code) that I can use for a basecoat.

 

[45Kevin]

If all you are doing to the metal is wire wheeling it an at worst a bit of grinding, you could use spot putty to fill in the grinding marks.

If you just use the wire wheel, or after grinding you still have some black metal, spray it with a rust killer of some kind before filling and priming.

I am just going by my recent (last summer) attempt at body work and it hasn't been time tested yet.

 

[PandaTelf]

Rage is good. Or bondo.
The amount of primer depends on the surface prep. Put a guide coat (light coat of spray pant) over the primer and sand with 400-600 grit till smooth. This makes all your low spots visible. If metal comes through before its smooth, spray more primer.
If you sand your primer smooth, there is no other prep needed before paint (except cleaning). Just make sure the primer is good and cured before you sand.
We usually sprayed 2-3 coats of color till covered and then 3 coats of clear. No prep between color and clear. You should spray the clear after the color is no longer tacky, but don't wait too long. The solvent in the clear will make the clear bond with the color.
The whole key to the paint adhering is the surface prep. There should be no "shine" on any surface you are filling or painting. The paint won't stick. A good way to clean the shine off the rest of the gate is red scotch brite and comet bathroom cleaner with water. I'd scuff the entire tail gate, paint the repair areas, and re-clear the whole thing.

Great advice dude, thanks!