problem with orange peeling

[craigcraig New User Find all posts View Profile Close craigcraig]

what causes orange peel? i'm cleaning the parts and when i think thier clean i clean them again. i tried prebaking but that didn't seem to make a difference. am i spaying it to thin or to thick? i'm curing at 380 around 15min.

[jtagger19 Experienced Metal Finisher Find all posts View Profile Close jtagger19]

most of the time it's over build ( too thick) .

[tavo1765 Amateur Metal Finisher Find all posts View Profile Close tavo1765]

Under cure, try heating it up for a longer time at 375 for 30 mins

[11111111 Amateur Metal Finisher Find all posts View Profile Close 11111111]

i go 450 for twenty and have good results

[tavo1765 Amateur Metal Finisher Find all posts View Profile Close tavo1765]

Yeah 450 for bigger parts at 10 mins, thing is you want to allow the powder to flow out before actual curing the longer the flow and time it takes at a certain temp the more controll you have over orange peel.

Things that effect orange peel in my previous experience is:

1. Moisture in the lines, humidity above 50-60%

2. Applying to little or too much powder, try to get a feel by going accross left and right counting how many times. example: A bracket, I would stay about 10" away and start to spray counting left to right about 3 times real slow working accross the part to get a nice dusted fully coated part, put it in the oven. If it comes out nice use that method and hany many times you went accross for parts that size, it works out to a certain thickness if you can repeat that process( works out as a math problem) lets say you have a large wheel, go left and right 6x to et a even coverage then place it in the oven, if you get a wavy finish, try only doing it 4x, this is just a basic way of getting a feel not an exact statment of explaing how to coat something.

3. Powder that has been stored incorrectly or powder that needs to be shifted to fluff it.

4. Crappy oven, if you have a oven that doesnt preform you wont get powder to flow out like water, it should turn to highly gloss wet looking paint when flowing.

5. Try using lower temps for a longer period of time, 350 40mins, 375 25mins, 400 for 15mins , 410 for 10mins

6. Powder flows out after 300f you can cure a part at 325 but over a long period of time.

[warchild Amateur Metal Finisher Find all posts View Profile Close warchild]

I been lucky. I have never had anything orange peel.
I guess if it ever does happen I know were to look.

[craigcraig New User Find all posts View Profile Close craigcraig]

thanks for all the info. my previous parts were coming out fine its the most recent ones that have been getting orange peel. its a good possibilty that it could be humidity, or moisture inthe line or even the powder needing sifted. i'm usually good about coating a consistant thickness. oven is pretty on to only about 10 deg off. thanks again for the info