Protecting exposed and new sheetmetal

[hawaiiz]

Aloha All - Never done auto body before but here goes

 

What should I use to protect exposed and new sheetmetal between procedures - Grind, cut, weld, shape before epoxy primer/Body Filler

 

Im leaning tword spray can primers that Ill sand off before filler is applied, and if so does the brand of primer matter??

 

Also is using Rage Extreme, should I still use "Metal to Metal" for gaps and holes Etc???????

 

This weekend I will attempt to start patching holes. As I will only get about 6 hour runs once or twice a week I trying to come up with a plan.

 

Im starting on the rear end, filling in the shave and mocking up the rear 3 peice spoiler I plan to fill in.

 

Thanks in advanced. HawaiiZ

[Brad-ManQ45]

If the car is in a garahe and won'y get rained on - use Ospho.

 

I got some at NAPA, much cheaper than PickleX. I have had my car down to metal in one fenderwell area for over 2 weeks and no rust.

 

If the car cannot be out of the rain, the only recourse is epoxy primer - rattle can WILL NOT prevent rust - it is porous.

[hawaiiz]

Aloha - Yes I have a gallon of ospho I picked up. Ive heard it not good to leave under certian primerspaints. I like the idea, its cheap insurance, I imagine Ill still sand it off before the filler or epoxy primer then. Thanks HawaiiZ

[hawaiiz]

I had a hour this morning to play with the wirefeed welder. I put in some new .30 flux core wire and new tip. I practiced stitch welding on some 22guage galve sheet metal. So far so good. Build the cofidence a little.

 

So question - I have the 3 peice spoiler to install and I want to intergrate it into the sheetmetal. Yesterday I was looking at Fiberglass.

 

The spoiler is fiberglass, should I try to glass it in or better to use gold filler?? Any thoughts HawaiiZ

[JimmyZ]

Here's a page I made for someone just getting into it...

 

http://warbuddies.homestead.com/RestoHelp.html

 

It's not all inclusive but it should help

 

Jim

[sweetleaf]

For stuff as thin as 22 I would use .25 . It should make it a little easier to get a smaller bead with less burn through.

[hawaiiz]

Excellent write up - I have read it before

 

Since Im still not sure what to do Ive been just spray can primer after I work on an area. Since I live in hawaii I called some paint supply stores but shipping is expensive and since its considered hazardous even more expensive.

 

Since I most likey will be repair/repaint every 3 years or so (due to rust coming back until I can do the full rotissiery deal) I plan to use inexpensive paint (single stage enamel ??) What line of primers should I order or is the stuff at Napa OK??

 

Thanks Again HawaiiZ

 

Quote

List primers in order of application...

Zinc ChromateUsed in lieu of phosphoric acid treatment on bare metal. It does not adhere well to paint so limit your overlap if painting a patch of bare steel on a painted panel. IMHO it should only be used on metal with no history of severe corrosion. If the part is too complex to acid treat then go ahead. Since it's better to treat the metal I rarely use ZC primer and skip straight to epoxy. ZC needs to be topcoated "immediately" because it is not a moisture barrier.

Epoxy PrimerCan't sing enough praise of this stuff. It provides an impermeable barrier to moisture. Apply it to treated steel or over ZC primer. On areas that have been sanded through during bodywork reapply to seal the body filler and metal before applying next primer. Some epoxy primers can be thinned with acetone to spray more evenly or through a smaller nozzle. If the car has a chance of being exposed to weather then apply unthinned. Some epoxies need to "stage" or set for 15 -30 min after mixing. The more expensive epoxies are ready to spray as soon as they are mixed. Always stir the can with a fresh stick and never allow any mixed epoxy or it's hardener to come in contact with the unmixed stuff in the can. If not topcoated within a few days epoxy needs to be scuffed and reapplied as the chemical bonding to the next layer won't happen when it is cured.

Apply body filler over 40 grit scuffed epoxy. After sanding body filler there may be bare metal exposed. Reapply epoxy to this area before leaving bare metal exposed for more than a day.

Avoid long term exposure of epoxy to sunlight.

Sprayable Polyester Filler Just like the name says it is polyester glazing putty in a gun sprayable form! In PPG's Omni line it is known as...

MX241 Gray/ MX245 Buff Polyester Primer/Filler. You only need this stuff if you are having issues with bodywork over large areas. It easily hides gouges in metal from coarse grit sandpaper.

If you have a wavy panel due to sandblasting or have a large area of body filler to level out this stuff is the best! Hoods, doors, esentially any flat areas can be made mirror flat with this stuff. (Assuming you sand it properly) As an example of it's filling abilities one guy taped a quarter on a panel, buried and completely hid it after sanding. That is almost the limit of it's filling abilities. Mix it in small quantities as it sets quickly! Mix only enough to get you through a single coat over the affected area. Clean your gun out after each pass. The pot life may say 45 minutes but even in my 2.0 tipped primer gun it starts coming out like molasses at the end of the second pass. (Could be the Florida heat)

High-Build Primer Any paint defects such as orange peel or sand scratches cannot be hidden by the topcoat. High build primer is applied prior to topcoating . High build is wet sanded with 220 grit to knock the peaks off and finished with 400, progressing to 600 grit. 600 grit can be used as a final grade but there are sometimes adhesion issues with such a fine surface. Apply high build as booth time gets near so that a good chemical bond will occur. (Preferably less than three days)

Hi-build hardens in the gun quickly so mix enough for one coat and clean your gun after each coat on hot days. Apply this stuff good and wet and avoid spraying too far away as it will dry before it hits the surface. This will leave you with little balls of primer sitting on top of the rest. Try not to get it in areas which you won't be sanding. If you do then you can use a scotch-brite pad to remove/level it.

Primer/Sealer This is applied immediately before the topcoat goes on. As the name says it "seals" the work so that nothing underneath can get through and vice/versa. Consider it insurance that is optional but HIGHLY recommended. I've painted without using it. If you are using a cheap basecoat or a single stage with lots of translucence (clear) then you need to use it.