how many coats of VHT?

So should I cure it or no... the label says that the "special properties" of the VHT won't work unless it's cured....I painted it and it is sitting in my friends garage. I was going to put 3 more coats on, then once it is dried I was going to aim my camping propane heater at it to get it up to a couple hundred degrees and cure it...he don't care about the smell...plus I can't fit the header into my oven anyways...I tried, and subsequently got in trouble

A guy I know put VHT on his cb750 headers and they are now peeling, he didn;t cure it...I don't want peeling, I ride a Kawasaki

I have "cured" my pipe by temporarily mounting it and running the bike for a few minutes. Only problem with that is that front pipes get hot quicker than muffler. You would have to ride the bike for awhile to heat the muffler. Do you need to cure between coats?

Maybe if you have a powder coater near by they may let you cure it in there oven. Just a idea.

I aimed my propane heater on my header today and I think it worked well...the header portion got nice and hot, too hot to touch...I thn moved it to the midle portion of the pipe, and then the back...each part got about an hour of heat...I will put a couple more coats and then do it again.

That's the way I used to do it and anything I did it do worked out great. Lasted a good long time. Even painted the motor and did it this way. Never had any problems with it afterwards. Headers are notorious though for needing repaint every so often so it will need touched up sooner or later but it should hold up for awhile. I noticed a black header will turn a whitish grey color after awhile. Paint stayed on but lost some of it's darkness over time.

9am53 wrote:

I got my header back from my mechanic today all nice and sandblasted. I cleaned it off with brake cleaner and put on 2 coats of VHT flat black...will this be enough?

Actually (and it says this on the can) you only want to put on enough paint to color it. I used the stuff for a lot of years, and it doesn't last. The extreme heat will soften the paint and it will oxidize off over time. I used to strip mine and respray them every few years.

You will get best results if you paint it and let it dry overnight, then use a heat gun to gradually heat the paint and header. Hang it from a rafter in the garage with a coat hangar and spray hot air inside the pipes and on the outside surface, moving the heat around to keep from blistering it. If you don't cook the paint on, it doesn't last.

I never tried painting the inside, it might work? The main problem aera is right by the exhaust port and the first 12" of pipe (around the first curve). That might benefit from inner paint.

9am53 wrote:

cool, I will put a few more coats on and make sure to do the inside. Then I am going to cure it with my camping heater...we'll see how it turns out!

IMHO, you put all the coats on at the same time to make sure they bond and fuse together into solid paint layer. I tried to "touch up" one of mine the day after I initially painted it and it flaked off. I ended up having to re strip it and do it over.

racer54 wrote:

I noticed a black header will turn a whitish grey color after awhile. Paint stayed on but lost some of it's darkness over time.

Yep, exactly what happens. Paint softens up and oxidizes away. Also, be careful not to spill oil as that will stain the paint. NOTE: the paint does not protect against rust as well as you want. My pipes eventually pitted underneath even though the paint surface appeared to be there.

THanks guys. I think I will just cure it on there now, and not add any more paint. If this lasts a few years I will be happy, I will have a nice chrome kerker by then

As mentioned, follow the can directions....

Another thing I most likely missed, no mention of primer here! Again, probably missed it...

Anyhoot, here's what I have had with exceptionally good results for I don't care what you're painting, PREP is everything!

Sand blast/sand the exhaust clean and smooth... Then prep pad it. If chrome as in my head light shells, scotch pad for a ruff surface for the paint to adhere to.

Metal etch Primer 3 med coats.... Let fully cure to can directions then wet sand smooth. Then another 3 coats & wet sand smooth once cured.

For paint, pretty much the same 3 light coats then wet sand smooth once cured. Then 3 (light) to 5 (medium) coats and let fully cure then wet sand smooth.

If using clear coat, spray 3 light coats and wet sand smooth once cured. 3-5 more light coats then wet sand smooth once cured.

NOTE: Most automotive clear coats I have researched won;t hold up to heat but there are can heat clear coats... Not sure of their results... Sorry but on your own on this one.... Maybe some of the others can add to this clear concept on heated parts.

Then using rubbing compound, hand rub to a brilliant shine.

In this method, sure it's work but no one and I repeat no one will know the difference... And it WILL hold up to anything you throw at it such as water, gas or sunshine....

In my project file I have posted images and results so up to you.... or follow the link to the headlight shell can paint I posted in the file base...

kzrider.com/index.php?option=com_docman&...d&gid=455&Itemid=108

Good luck and show some pre & post images throughout your project... Let us know how it turns out....

OMR

for Patton! :woohoo:

POR-15 makes some very high heat paint for exhaust. Its not suppose to burn off up to 1200 degrees. I bought some in silver and used it on my Camaro headers.I haven't run it yet to see if it works though.But I do know regular POR-15 is good for up to 400 degrees and I've tested that before.

I thought the black VHT was supposed to be good to 1500F (?) It is supposed to be the highest heat paint available, anyway that's what they claim on the can. IMHO, no paint is going to be able to handle the heat of a single walled pipe at the first turn of the header pipe. That turns chrome a deep royal blue. The black paint lasts a while but does soften up and oxidize eventually.