Dupli-color engine enamel paint

[Guest]

I painted my engine cover with Dupli-color engine enamel paint. The result looked beautiful.

DSC_0872.jpg

[dpascal]

I then went on to perform this high temp break in procedure:

1. Let the paint dry for 10 hours.
2. Heat the color to 80 degrees Celsius for 30 min.
3. Heat the color to 120 degrees Celsius for 30 min.
4. Heat the color to 160 degrees Celsius for 30 min.
5. Heat the color to 200 degrees Celsius for 30 min.

As seen in the attached picture, the result was a disastrous Smallpox epidemic threatening to consume all man kind.

DSC_0930.jpg

At this point I understood that cool-down periods are needed between temperature increases so I cleaned the head cover down to bare aluminum and executed the following procedure instead:

1. Let the paint dry for 10 hours.
2. Heat the color to 80 degrees Celsius for 30 min.
3. Let the part cool down to room temp.
4. Heat the color to 120 degrees Celsius for 30 min.
5. Let the part cool down to room temp.
6. Heat the color to 160 degrees Celsius for 30 min.
7. Let the part cool down to room temp.
8. Heat the color to 200 degrees Celsius for 30 min.

Up to step 7, everything went fine but after 10 minutes at 200 degrees I started to see very few, but still apparent, tiny bubbles. Not as worse as seen when executing the no-cool-down process but still there.

What am I doing wrong? Is the Dupli-color engine enamel intended to survive 200 degree Celsius?

[sinkankan]

Sounds like your actually boiling the paint to a nuclear level, this break all the bonding agents in the paints chemical make-up. Heating the part gives the paint a chance to actively bond to the part, but if the part is too hot it will repel the paint, hence the spotting where the paint is landing on the part, partially cooling it and trying to bond to the part.
I'd try a low temp heating first on a clean surface, and put the paint into a sauce pan on a tray to get it off the bottom and slowly bring the water to a boil. Remember before you pick it up the can will be hot, so use gloves.

[Nessism]

200C is most likely beyond the limit for that paint. The engine shouldn't get that hot in use so maybe stop at 160.

[jabcb]

Dupi-Color resists temperatures up to 500°F intermittently.

http://duplicolor.com/product/engine-enamel-with-ceramic

200 °C is 392 °F.
I thought Dupi-Color is heat cured up to 200 ~ 250 °F, or 93 ~ 121 °C.

[dpascal]

Dupli-color engine enamel paint should resist bursts of up to 500 F, according to the manufacturer.

http://i.imgur.com/pgr5vF7.jpg

Anyway, I'm out of dupli-color. I thoroughly cleaned the burnt paint (5 hours of nightmare) and my next attempt will be with PJ1 engine paint.

http://pj1.com/i-19004781-pj1-fast-black-engine-paint-500f-gloss-black.html

There are no curing instructions for the PJ1 paint so I'll give their customer support a call tomorrow.

[Cipher]

get a buffing wheel and polish it up.

[dpascal]

Dupli-color engine enamel paint vs. PJ1 engine enamel paint

Well there is a twist in the plot ....
After I sprayed my engine head cover with PJ1 black gloss engine enamel paint I ran the procedure below and the paint not only survived but is now hard as a rock and looks beautiful.
Based on my experiments I can clearly tell that PJ1 is more durable and can withstand 40 minutes of 210C or 410F.

The procedure :
1. Let the paint dry for 10 hours.
2. Heat the part to 90 degrees Celsius for 30 min.
3. Let the part cool down to room temp.
4. Heat the part to 150 degrees Celsius for 30 min.
5. Let the part cool down to room temp.
6. Heat the color to 210 degrees Celsius for 30 min.
7. Let the part cool down to room temp.

An interesting fact is that the curing smell (release of solvents or adhesion process) still took place well into the 210C stage.

[jabcb]

Good that its worked out for you.


Another interesting paint is the Eastwood 2K Aerospray HT Ceramic Engine Paint Gloss Black. They also have a matching primer.
Both are two component paints that you mix in the can.
Its a good bit more expensive, but maybe you get what you pay for.

http://www.eastwood.com/2k-aerospray-ht-ceramic-engine-paint-gloss-black.html

[BurntKittyForge]

I noticed some new (?) silicone based paint HERE (I know, advance auto but that's where I saw it...

Says resists up to 1500. I'll probably go with that for just the block part of engine , and then sand the tips of cooling fins.
Been polishing the heck out of the lower motor and some of top, finishing off with "mother's alum. polish" and nothing on finned part starting to look strange...

Odd thing, I fabricated the exhaust from header to custom (other MC) muffler and sprayed .99 cent/spray-can matte black on that section and it has not peeled or burned, I really just used it as a mock up but it's lasted around hundred miles atleast...weird I guess.Need to paint the "SUZUKI" on both covers black soon.
Thanks for the tips.

[londonboards]

One thing that I have found in the preparation stage; make sure it is clean, clean and clean before painting. Then put in the over at 200C for some time. This gets all the crap out of the metal pores. Then clean again and again (with paint thinners or acetone). Use a primer (like VHT) and do not put the paint on too thick. Multiple thinner coats.



(The bumpy stuff is underlying corrosion - I had this item blasted before painting)