paint question

[steve from staten island]

My body on my 69 satellite conv. is completed and painted. Now my problem is this,i got a fantastic deal on the body work and paint and the car looks great and is straight as new. The car was blasted,the engine bay was blasted as was the interior and trunk. The underside was rust free but was not blasted. When the body was being done the car must have been two and a half feet off the floor and the entire area underbody was wire wheeled and primed with some kind of polyurethane primer. The engine bay,complete interior trunk area were painted the body color and the engine bay was cleared. When he painted the engine bay he went back down though the transmission tunnel as far as he could reach. Again i got a great price but the underneath is not painted,just primed. My question is,the car is going to be a driver but i still want it to look good. All the wheel wells were undercoated so should i just spray black undercoat on the bottom or should i just paint it chassis black with a brush? Overspray is a area of concern. I would have liked to have it the body color but taking it somewhere is going to be over my budget and the guy who did the work originally is to far and to busy plus he would not paint it with out a rotisserie. So what thoughts do some of you have as you have more experience than me and thanks again

 

[NJRR]

IMHO, if the car is going to be a driver and you will drive it in weather, you want to put as much protection on the underside as possible. So, brushing on a coat of black will add protection. Then undercoating will add even more protection and will cover the fact that the bottom was brush painted and is not the body color. Both can be done pretty inexpensively by you.

 

[Propwash]

I agree with NJ. If it's going to be a driver, protect it the best you can. I wouldn't use the rubberized undercoating out of a can, that's for dang sure. Something like a bed liner (epoxy based) is much better for keeping air/moisture from reaching the base metal. I've used SEM Rock It Liner with real good results. Kit comes with a gun, but you will need a compressor to spray it. It is a 2:1 with catalyst, so it does get hard as a rock. Pretty easy to spray. You will need to spend a few hours masking the car and around it. IMO, that isn't nothing compared to dealing with rust on your underside. It will act as a sound barrier/deadener as well. 1 kit would do the whole underside.

SEM kit: http://www.summitracing.com/parts/smm-42260?seid=srese1&gclid=CK2rgsP3grwCFexFMgodQmEApg

You could also go the more period correct route. Resto Rick sells an undercoating that duplicates the factory look as well. Although it is not asphalt based like the original, but rubberized instead, it does look very similar to what Mopar used. There are several guys here that have used. You would need buy and spray on with a body schutz gun, and again, a compressor would be needed.

http://www.restorick.com/proddetail.asp?prod=Undercoat

If you go the paint route, the simple fact of the matter is that anything sprayed out of a gun vs. being brushed on will be more durable. Main reason being is the catalyst/hardener added to the stuff sprayed out of a gun. You can buy a 2 part, pre-mixed paint out of a can now days, but it isn't cheap (20-25 a can). A regular rattle can would probably give you a better uniformed application, but could be tricky being you'll be spraying from the underside and is going to be tough to keep the can level.

IMO, best bet I could see for maximum protection and going with the brush or roll on route would be to use rust bullet (Or POR15 if you prefer-myself I wouldn't). Roll on a couple coats of the silver rust bullet, scuff till dull with scotch-brite pads and then apply a coat of two of the black shell. Rolling on, with using a brush in the tight spots would work best for a uniformed coating.That would create a pretty tough coating for your underside as well.

http://www.summitracing.com/search/brand/rust-bullet?kr=rust%20bullet&SortBy=BestKeywordMatch&SortOrder=Ascending

Whatever route you go, I wouldn't be afraid of spending more than ample time cleaning and prepping the underside. If you don't get real nice and clean first, what ever you apply on after will be pointless. And mask, mask, mask away.

Good luck what ever route you go.

 

[soundhd]

If it is NOT going to be driven in the winter or very rarely in the rain I say paint the undercarriage any color you want.....but if it going be driven in all types of weather undercoat everything if you want it to last.

 

[Meep-Meep]

The factory process was to dip the lower part of the body in a gray colored solution that resembled the inside of a wishing machine tub. Then after that it got a coat of the green zinc chromate primer from about the middle of the door up. The spray primer color might vary and I don't know the particulars from plant to plant. My LA built 68 RR is medium/dark gray on the bottom with the green on the top. In your case if you wanted to duplicate the factory look (all body color under the car is NOT correct) you would use some sort of a primer. Prop made some great suggestions for protection as he is located in a rust factory, but you can do well with any method. And I'll reiterate. Clean, clean and clean. Especially silicone. There are a lot of gaps and sometimes it's best to just use a brush.

 

[Propwash]

he is located in a rust factory

LOL....Good way to put it Meep!

 

[bigbear]

Just my two cents , but I agree with "NJRR" as well . Being from the North east , I know what road's and road conditions can be like and if your car is going to be a driver then you want to protect the underside the best you can . I'd say paint the underside with a good quality paint ( getting in all the nooks and crannies ) and then undercoat it . I got lucky with our Dart that were now selling . When I repainted the car it all ready had the factory undercoating still under it . So all I had to do to freshen it up was go over it with a light coating of undercoating and it look's as good as new under the car . But beware , It can get a little messy . So mask it off "real good" and were some cloth's that you don't care about with gloves .

 

[HEMI-ITIS]

IMHO, if the car is going to be a driver and you will drive it in weather, you want to put as much protection on the underside as possible. So, brushing on a coat of black will add protection. Then undercoating will add even more protection and will cover the fact that the bottom was brush painted and is not the body color. Both can be done pretty inexpensively by you.

I agree:yes:

 

[RS23VOA]

3M makes an undercoating that comes in a 16oz can(i think) that takes a special 3M gun to put it on with your air supply. Thats what i use. I get it at the local paint supply store.

http://solutions.3m.com/wps/portal/...0000_nid=GSVMV1M4RLgsQH8HT14PGTglKZNKFXQPLGbl

http://solutions.3m.com/wps/portal/...0000_nid=LL22JJR03MgsQH8HT14PGTgl2XJ0F7P834bl

 

[steve from staten island]

Thank You so much. You guys are the best