undercarriage

[01somta]

I am about to get my car back from getting a mini tub and new floor pans put in. When searching on undercarriage coating all I can find is paint or coating to use on rusted or pre-coated metal. My question is what is the best thing to use on brand new undercarriages and what prep work is involved (just scuffing it up?). I will need to use something in a rattle can or brush form. Also, is it ok to do this before the car is painted or should it be done after the car is painted?

Thanks for your help

Dustin

[Gordz32]

If you want you can do a spray on undercoating. But at BOS we do this after paint so that that its nice and fresh and no sanding residue gets on it because it hard to get that stuff off after. You can always touch it up after and its very durable. All u need to do is scuff it.

[01somta]

Does anybody have a good product that would work good on new metal.

[HILROD]

If it's all new metal, you can pick what you like the looks of best. All you'd need to do it scuff it up a little, (scotchbrite), and prime it then shoot on any color or texture, you'd like. I've done semi gloss black, body color, and contrasting gloss colors before. Also, you could leave it smooth, or texture coat. The texture could be black, or painted any color. Decide what you like then ask away.

[01somta]

If it's all new metal, you can pick what you like the looks of best. All you'd need to do it scuff it up a little, (scotchbrite), and prime it then shoot on any color or texture, you'd like. I've done semi gloss black, body color, and contrasting gloss colors before. Also, you could leave it smooth, or texture coat. The texture could be black, or painted any color. Decide what you like then ask away.

I would like something black (not glossy, satin at the most) and to have some what of a texture if all possible. It needs to be something in a rattle car or brushable. Thanks Dustin.

[HILROD]

Well with those questions answered, you can scuff it then prime, (spray can etch primer), and seam seal, then get some chipgaurd, (spraycan), then get some SEM trim paint , (also spraycan), it comes in different gloss levels, or any other rattle can color. If you use chipgaurd instead of uder coating under the paint it'll lay smother and be more durable and clean off easy. Under coating lays a little rougher, and heat and any fluid leaks can easily soften it up.

[DLinson]

I did the above method of prime, chip guard, then paint. I used a single stage urethane paint but a spray can would be okay. It does clean up easily. I kept the frame smooth and the sheetmetal textured. The smooth paint definitely chips easier. I don't think I have any chips in the textured areas.

Dennis

[DLinson]

Here are a couple of pictures of the finished under side of the car.

You can paint directly over the chip guard and I believe if you spray it withing a certain amount of time, you don't have to scuff it up.

Dennis

[01somta]

Well with those questions answered, you can scuff it then prime, (spray can etch primer), and seam seal, then get some chipgaurd, (spraycan), then get some SEM trim paint , (also spraycan), it comes in different gloss levels, or any other rattle can color. If you use chipgaurd instead of uder coating under the paint it'll lay smother and be more durable and clean off easy. Under coating lays a little rougher, and heat and any fluid leaks can easily soften it up.

Can you give me some brands and/or part numbers for the rattle can etching primer and the rattle can chipgaurd.

[HILROD]

You can get the primer from Ace hardware, or Autozone. I'll have to check, I think it's Duplicolor. Self-etching primer, it's dull green. The chipgaurd can be whatever is available to you local. If you can't find it anywhere paint supply stores carry spraycans. Just make sure when you top coat it, spray it on good the first couple coats. Get it covered well, then spray it lighter and more even on the last coat for semi-gloss.

[DLinson]

I used SEM brand self etching prier adn chip guard. The satin black etching primer part number is 39673 and the satin black chip guard is 39813. I think it only took three cans to do the entire underside of my Nova including the wheel wells. I bought the SEM products from a local paint and body supply shop. I have also found it at autoparts stores. SEM also sells a satin black or trim black spay paint. That sprays on really nice and even. I used it to paint the front side of my core support behind the grill.

Dennis

[01somta]

Am I going to have any problems spraying these rattle cans since they are going to be pretty much parallel to the ground, or is there a trick to it? Most other rattle cans won't spray worth a crap being held like that.

[HILROD]

Not really, you can tip them just a little and they'll spray. It actually works better than spraying down. I usually do the flat areas with a newer can and finish the cans off on a curved or higher up area. Just jack the car up as high as your saftey stands allow maybe a little bit more on one end, and let 'er rip! Wear a respirator as you'll be in a paint cloud.

[01somta]

So as stated in posted #11 should I start with 3 cans of each? How many coats of primer, chip guard, and paint should I spray? As long as each coat is sprayed right after the last, I shouldn't have to doing any sanding (prep) for the next coat should I? Also does it have to be an etching primer?
Thanks again for everyones help.

[01somta]

Also, I was searching SEM website and I seen that they have a heavy texture chipguard, would that be better. Do you think it would look more like a spray on bedliner. Does the regular chipguard have a textured look to it?

[HILROD]

All of this depends on how much area you'll be doing but, you'll only need to put on a coat or two of the primer, so I'd guess around 2-3 cans. The chipgaurd depends on how you want it to look. The smoother the easier to clean later, and the less paint it'll take to cover. A heavy chipgaurd'll use more product to cover and cover with paint. It all depends on what you want. On my Camaro I made the texture heavier in the weelwells and in more wearable areas, and less in others.

[TnBlkC230WZ]

If it is new metal, doesn't it have and EDP coating on it? Should be able scuff and put your undercoating on. The EDP is comprable to an epoxy primer, so why take it off and put and etching primer on?

[01somta]

Most of the floor pan is EDP coated, the trunk pan and wheel tubs are all custom fab'ed new sheetmetal.

[yoboy sawyer]

HEy did you look in por 15 it is liquid powercoating

[01somta]

HEy did you look in por 15 it is liquid powercoating

I did some reading on the por 15 a while back, but everything that I read was mentioning using it on rusted metal. All my undercarriage is new metal, that is why I decided against the por 15.

[4thgenz]

how long before you get it painted??? if more than a few days...i would def put something on it....you dont want that new metal to get all rusted up!!

[67speedfreak]

Here is a pic of what we did with Agent Orange.
I would coat the metal with epoxy Primer, I use DP 90 and then spray it with bed liner material. We use Raptor coating.
It is a two part catalyzed bed liner material that mixes in it's own bottle and comes with a gun to spray it with.

This is the first time we used it but I am very impressed. Gets very hard and is durable.

The kit is around 100 bucks and you would have some left over. It comes with four bottles of bed liner and one bottle of catalyst so you just mix one at a time a only use what you need.

https://static1.pt-content.com/images/pt/2007/12/IMG_1759-1.jpg