Undercoating Suggestions..., Wurth SKS...POR15...Paint??? Options

[ty914]

Finally some progress is being made here. I have the undercoating almost gone. Surprise no rust!!! So here is the question…what to do with it now? I was planning on spraying it with Wurth SKS. I do not plan on making the underside perfect so is this the best option? I just spent a week on my back to just put it back on? So what have you done to your underside? Pictures and lessons learned please…

[seanery]

paint sounds like a winner to me.

[Lou W]

I used 3m Body Schutz on mine, and left it the black color, since then, I shot clear over it. I am very happy with the results. Check out my blog for more pictures. I looked into the Wurth product, it's expense, and you'll need to buy their application gun, which isn't cheap either.

[Phoenix-MN]

I used Wurth SKS and yes it is a little more spendy but the results are nice. The Wurth gun isn't that expensive but just about any body schutz gun will work.

My results
http://www.phoenixhobbies.com/html/paint.html

Paul

[Eddie Williams]

you can get wurths and the gun fairly cheap at harbor freight

[2-OH!]

I'm sure this idea will be poo-poo'd but, here goes...

I stripped it first to make certain there was no rust...Treated or replaced bad areas I found...POR'd the entire underside then covered it with a product called "Herculiner"...It's a brushable product similar to Rhino liner or Linex liner they put in the bed of pick-up trucks...Bottom pan and all wheel wells...2 coats...Looks great and is ureathane based so you can paint over it...Which is what I plan to do with the body color...

It has very small (tiny) bits of rubber in it and will help repel road rocks and noise...Just painting bare metal will make for a noisy ride...Mine will be a daily driver not a racer...

Oh, by the way, it's available at PEP Boys at $39.00 - 1/2 gallon...

2-OH!

[Eddie Williams]

hope you didn't get any on your hootus!

[BIGKAT_83]

I used 1 liter of Wurth SKS and saw that it would get pretty pricey to do the bottom and trunks with it. So I used U-POL gravitex plus sprayed just like the wurth and was less than half the price. I could not tell any difference in the two.

Bob (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif)

[ty914]

Thanks guys for the help...I guess undercoating is undercoating and it all works fine. There hasn't been anything shot down. Maybe I should have started a post about the "club" logo...and get more feed back.

[Katmanken]

I'd put a coat of 2 part catalyzed primer on it first. Dupont Variprime is a great self etching 2 part catalyzed primer. Sets up hard, can be stored in a sealed jar mixed for a couple of weeks without hardening, and has some zinc for protection.

Then I 'd add the undercoating.

Why? Not much sticks to bare metal well except primers and unlike most primers, variprime is NOT POROUS.

Second, get a nick or stone chip in the undercoating and water can wick up and cause rust to form on bare metal. Unprotected metal rusts WAY faster than protected metal. And, if the undercoating doesn't stick well to the bare metal, it will seperate easier and the rust will spread quickly from water wicking betweent he undercoating and bare metal.

So, I like the Variprime for a good hardened basic waterproof rust protection coat and primer combo, and the Wurth (or equivalent) undercoating to act as a shock absorber for the rocks and sand that will try to blast the paint off the bottom of the car.

Do what you want. They aren't making any more teeners.

Oh yeah, Variprime must be sprayed, doesn't brush well.

Ken

[ty914]

Dude...thanks Ken. Very helpful in my quest for knowlege. I told my wife this will be the "last" time this would be done to "this" car. So I want it to last and be done right. I hope this car is still on the road another 30 years from now.

[Katmanken]

You are welcome.

You do need to Ospho the bottom of the car to convert the remaining rust to magnetite, then the Variprime, and then the Wurth.

I can't find Ospho locally so I use a Dupont auto body equivalent. It has 2 bottles. Contents of bottle 1 mix with water and convert the rust. Contents of bottle 2 neutralize the first and add a little zinc coating. Then the variprime.

I lived on the beach in Florida in perpetual salt spray. Had to learn what worked.

Ken