My bike paint project came to a screeching halt last week with technical problems...since I am not a painter I have a good friend who has been mentoring me....even then things can go wrong with paint. Painting is not for the faint of heart...It is also not rocket science...no..it is more like vodoo stuff. I would like to share some insights and pics of things I never ever thought about before and now have carnal knowledge of
1. Paint is not only paint...it is a solvent also. So, when you mess something up like sanding and you go right through to the plastic...well guess what...you went through the clear coat, the paint coat, and through the primer coat...you are screwed dude... Why...because paints are solvents and will react chemically with the other coats you went through where you have exposed new edges on your way to the center of the earth...
2. Never ever ever...let me repeat that again for the thick skulled ones like me...never ever ever use a rattle can in late winter time to primer your paint...Why..because they spit extra globs of paint out when everything is not warm and fuzzy. I didn't have my compressor set up and we decided to "rattle can" it on. When you get a spitter...and there were hundreds of these little incidents while rattle canning all of the plastics..you think..no big thing..just sand them down...which i did numerous times...the problem isn't the flatness...the problem is now you have an extra bit of pigment density on the plastic. When you color coat it with some colors these extra bits of pigment will pop out to the eye. Even after 4 color coats and 4 clear coats you can still see some of them. The lesson I have been taught and I hope you are listening to me if you consider painting your bike...anything that shows up on the primer surface that is not uniformily the same will show through in your color coats...We are not talking small dents, scratches, runs...and such...we are talking pigment differences. I have shown my panels to two different professional painters with over 40 years experience between them, and unknown to the other, and they both said the same thing....never use a rattle can...Use an expoxy catalytic primer.
3. Did you know that plastic is the evilest thing I have ever met? I have sanded the front light nacelle that holds the turn signal and air intake down to bear plastic 3 times, stripped it from fully painted to primer coat 3 times. I have been told by several pros that when they make the plastics they pour a chemical into the mold with the plastic pellets. They then heat the mold to melt the plastic pellets. Then they allow it to cool. When the mold is reheated the chemical, previously mentioned, allows the mold to pop free of the surface of the mold. So, when you are sanding and you go through the factory oem coat you have created a new set of dynamics chemically to deal with. Your primer is now reacting with this mold release chemical. On this one little spot on the nacelle I sanded a little too much to get this scratch out and went too deep...naked eye could not tell it...we are talking subatomic level stuff here. Then when you spray your primer back on it crinkles up on you...you sand it all down again and now the spot where it was before has gotten bigger....I am not lying to tell you I have over 8 hours on this one nacelle...Google and painter's advice is this...you have to scrub the heck out of it with hot hot hot water and soap...I used ajax...then use isopropyl alcohol...then when it is dry...you have to use a product like Bulldog plastic adhesion promoter...lay on a light layer...allow it to flash...do it again...allow it to flash...and within 15 minutes put a primer coat down
4. Tomorrow begins a restart of the tank job..I will take airplane stripper and bag the tank in that and take it all the way down to bare metal and begin all over again...I was told to get aluminum tape to seal the top and bottom of tank...
You can see on the pics the areas on the tank that the sanding got to aggressive and destroyed it...both painters said they wouldn't even try to repair it...too technically difficult to do...easier to start over...
As sad as this is...It is a learning experience and I am not discouraged...
1. Paint is not only paint...it is a solvent also. So, when you mess something up like sanding and you go right through to the plastic...well guess what...you went through the clear coat, the paint coat, and through the primer coat...you are screwed dude... Why...because paints are solvents and will react chemically with the other coats you went through where you have exposed new edges on your way to the center of the earth...
2. Never ever ever...let me repeat that again for the thick skulled ones like me...never ever ever use a rattle can in late winter time to primer your paint...Why..because they spit extra globs of paint out when everything is not warm and fuzzy. I didn't have my compressor set up and we decided to "rattle can" it on. When you get a spitter...and there were hundreds of these little incidents while rattle canning all of the plastics..you think..no big thing..just sand them down...which i did numerous times...the problem isn't the flatness...the problem is now you have an extra bit of pigment density on the plastic. When you color coat it with some colors these extra bits of pigment will pop out to the eye. Even after 4 color coats and 4 clear coats you can still see some of them. The lesson I have been taught and I hope you are listening to me if you consider painting your bike...anything that shows up on the primer surface that is not uniformily the same will show through in your color coats...We are not talking small dents, scratches, runs...and such...we are talking pigment differences. I have shown my panels to two different professional painters with over 40 years experience between them, and unknown to the other, and they both said the same thing....never use a rattle can...Use an expoxy catalytic primer.
3. Did you know that plastic is the evilest thing I have ever met? I have sanded the front light nacelle that holds the turn signal and air intake down to bear plastic 3 times, stripped it from fully painted to primer coat 3 times. I have been told by several pros that when they make the plastics they pour a chemical into the mold with the plastic pellets. They then heat the mold to melt the plastic pellets. Then they allow it to cool. When the mold is reheated the chemical, previously mentioned, allows the mold to pop free of the surface of the mold. So, when you are sanding and you go through the factory oem coat you have created a new set of dynamics chemically to deal with. Your primer is now reacting with this mold release chemical. On this one little spot on the nacelle I sanded a little too much to get this scratch out and went too deep...naked eye could not tell it...we are talking subatomic level stuff here. Then when you spray your primer back on it crinkles up on you...you sand it all down again and now the spot where it was before has gotten bigger....I am not lying to tell you I have over 8 hours on this one nacelle...Google and painter's advice is this...you have to scrub the heck out of it with hot hot hot water and soap...I used ajax...then use isopropyl alcohol...then when it is dry...you have to use a product like Bulldog plastic adhesion promoter...lay on a light layer...allow it to flash...do it again...allow it to flash...and within 15 minutes put a primer coat down
4. Tomorrow begins a restart of the tank job..I will take airplane stripper and bag the tank in that and take it all the way down to bare metal and begin all over again...I was told to get aluminum tape to seal the top and bottom of tank...
You can see on the pics the areas on the tank that the sanding got to aggressive and destroyed it...both painters said they wouldn't even try to repair it...too technically difficult to do...easier to start over...
As sad as this is...It is a learning experience and I am not discouraged...
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