| Author | Message | ||
     Grianp |
I just purchased a brand new hero blue windscreen and airbox to replace my old ones. I want to have them professionally clear coated for an extra layer of protection, especially the airbox from gas. Now will any automotive clear coat work, or does it have to be one specially made for plastics to allow for flexibility? For those who may have had this done, how much did it cost you? One last thing, The foam padding strip on the back of the windscreen, what purpose does that serve? The one on my current windscreen fell off long ago, but the new one has it. I was wondering what the benefits, if any, were to having it. I personally think it looks strange on there especially with the translucids. Thanks! | ||
| Bads1 |
Call Will Christman at The Sign Shop of Racine, Wisconsin. Hes done them a few times. 262-634-3000 | ||
| Zatco81 |
Automotive clear coat is somewhat flexible, you shouldn't have a problem. | ||
| Bads1 |
If its not done correctly its a big problem. You have one shot at it. | ||
| Zatco81 |
Why one shot? What kind of problem would you run into that would only give you one shot? (Message edited by zatco81 on August 07, 2009) | ||
| Sifo |
You can't simply sand blast the clear off if it starts failing. | ||
| Zatco81 |
Well...I guess if sandblasting plastic is your only other option then...yeah, you only have one shot. Might I suggest this?  Grianp--PM Sent (Message edited by zatco81 on August 07, 2009) | ||
| Bads1 |
First you do run a DA on it with some fine paper. You must be able to get adhesion. Your pretty much ready for clear but make sure your surface is clean of skin oil or any other residue. Use a tac clothe to wipe it off after you clean it. Spray your clear in a light coat first. Let that set up for 20 minutes. After that go to your next coat and repeat the process. Then your third coat will be heavier.... you want to make it look wet with out any orange peel. Thats the trick though.... if you get a run,you'll have to block sand that run out. If you burn through the clear??? Then you will most likely scuff the translucent surface as well. Then you have another can of worms.Its a touchy one. Best let a custom painter do it. | ||
| Nik |
Use a urethane clear coat with a flex additive. Use an adhesion promoter before the first coat. Bulldog 3-in-1 works good for both of those. You'll need to take the shine off the plastic before spraying, I use a red scotch brite. Anyway, here's the datasheet from DuPont with a more detailed how-to: http://www2.dupont.com/Surlyn/en_US/assets/downloa ds/reflections_coating_guide.pdf | ||
| Bads1 |
You don't need flex promoter. Funny how people think you need that on these parts.... you don't. And you can't use scotch brite on the whole surface. It won't give the bite needed and you may leave imperfections from the use of it. As far as Duponts how to??? Your kinda going against the rules per say to do this. Those directions are great if your going to paint first. | ||
| Nik |
The DuPont instructions very clearly spell out instructions for both applying a basecoat first, or just clearcoating molded in color plastics: "Clearcoating molded-in-color Surlyn Reflections® surface: Spray apply Plas-Stick™ Adhesion Promoter for Plastics 2322S Spray apply a two-component urethane clear ChromaClear® Multi-Use V-7500S 2K Urethane ClearCoat." "Clearcoating molded-in-color Surlyn Reflection Series® surfaces: Review Plas-Stick™ Adhesion Promoter for Plastics 2322S instructions in the ChromaSystem™ Technical Manual for application information for spraying this adhesion promoter onto a surface prepared under "Surface Preparation" guidelines provided above. (Note that Plas-Stick™ Flexible Adhesion Sealer 2340S should not be used as recommended in this instruction sheet.) Review ChromaClear® Multi-Use V-7500S instructions in the ChromaSystem™ Technical Manual for mixing and application information for spraying this clearcoat onto the basecoat." As far as the scotch brite pad, once again, from DuPonts instructions: "(1) The high gloss Surlyn Reflection Series® surface requires some roughening of the surface for adhesion. A medium duty abrasive pad (Scotch Brite red) rubbed over the surface several times will roughen the surface adequately. Excessive roughening or use of a highly abrasive pad may cause smearing or abrasion and damage the surface, which will subsequently show through in painting. Cold gas polishing does not provide acceptable polishing without smearing." It also very clearly states NOT to use sandpaper. And how would scuffing by hand with a red scotch brite leave imperfections when compared to attacking the thing with a DA and sandpaper? All you need to do is take the shine off. Sorry, but DuPoint, maker of both the plastics one of the better Urethane finishing systems > You. That document even includes adhesion test results (ref, Table 2) Where are your test results? You are right about probably not needing a flex additive though. They don't say to use any; I'm just used to using it by default with anything plastic. These are probably rigid enough. (Message edited by nik on August 07, 2009) | ||
| Bads1 |
Nik, Molded in color parts is the key word. Not translucent colored parts. Trust me I know what I'm talking about. My test results??? Well lets just say my Son is a Custom Airbrush Artist. Trained by a very close friend of mine that is a award winning custom painter. Me.... I spend countless hours working on all phases of both there work. Heres the proof.    We did the Queensryche bike's for Buell a couple years back. Good enough??? | ||
| Zatco81 |
Lots of good info here. As I stated in the PM I sent Grainp, I would lightly sand the plastics with 600-800 grit sandpaper. I don't think the Scotchbrite pads would scuff well enough on bare plastic although they work great on clear coat if you're repainting something. Be sure to use a sanding pad between your paper and your fingers so you don't sand "grooves" into the soft plastic. I think thats the imperfections possible with a scotchbrite. Flex additive isn't needed with a urethane clear coat. Urethane is already flexible. I did however spray adhesion promoter on my plastics before I painted them. May not have been necessary but deffinately won't do any harm. Haven't had any paint peel, flake, or bubble. Rocks at 60mph however will take it off. | ||
| Nik |
Molded in color parts is the key word. Not translucent colored parts. DuPont makes no differentiation between the two, only Buell marketing does. They're both Surlyn Reflections material. the difference is in the amount of pigments used and that the translucent has to be molded thinner. It's like the difference between urethane clear coat and urethane single stage color. The base material is the same, the single stage just has pigments to make it opaque. You can even mix the two for a translucent effect (great for 'smoking' lenses BTW) I may not be an award wining airbrush artist, but I am certified in automotive refinishing from my local vocational school, and was trained by award winning hot rod customizers. I'm also an engineer so I tend to trust datasheets and hard empirical results more than anecdotal experience. I've also done exactly what the OP wants to do (though not on my Buell, yet, specifically all the lenses on my car, made of a close relative to surlyn), in exactly the way DuPont describes (substituting generic urethane products) and its stood up to three years of sun and 'road debris' without any evidence of adhesion issues. As to red scotch bright not being good enough... the use of an adhesion promoter between the plastic and the paint forms a chemical bond; just as when you're doing a paint repair. You don't need the mechanical bond of sandpaper in this case. If done right, 6-800 grit, with a softblock by hand, and WET, it couldn't hurt though. Could probably smooth out any molding imperfections that way and end up with a really slick job if you took the time. | ||
| Grianp |
Thanks for all the feedback, it is much appreciated and I am sure others will find this info very useful. However, as I stated in my original post, I am having this professionally done. I do not have the time, patience, or equipment to do this. When it comes to painting I truly believe that you get what you pay for. So I am definitely having a shop do this. Plus if something does go wrong with the process, they are liable. I am not having that burden on my shoulders doing it myself. I just got to now choose where I want to go have it done. | ||
| Bads1 |
You don't understand what I'm saying so you paint your way.... try it show to me then we'll see. | ||
| Firebolt32 |
I'm also an engineer so I tend to trust datasheets and hard empirical results more than anecdotal experience.  | ||
| Bads1 |
Erik Buell is a engineer and damn fine one. He trusted us.  | ||
| Etennuly |
Gentlemen! Why can't we agree there could be more than one successful high quality way of doing it? If I were doing that particular job of just clear coating for protection, I would first clean it with a spirit wipe and or cleaner for plastics, wet sand with 1200 or 1500 grit using slightly soapy water, rinse clean, blow it dry, tack wipe, single adhesion promoter coat, two coats of high solids high quality clear coat, let it dry a few days, wet sand with 2000 grit, buff with my 3" mini buffer, using '3M Perfect It III' compound, hand glaze until dizzy. I use a lot of scotch brite for sanding, but I don't like what it can do to a soft surface like the Surlyn, or even ABS for that matter. Even the finer pads, if you look very closely at a soft surface, will be micro abraded as much as smooth sanded for what is needed to enhance adhesion. I find they are better suited for old surface time hardened surfaces prior to refinishing. If I were doing custom effects inside and outside of the cover I would, after prep, clear coat first in and out, then lay on the custom colors, then clear again, 2000 wet sand the outside to smooth out any lines, then one more clear coat, and then on to the wet sand and buff procedures. Grianp, Do you see why this kind of stuff gets expensive? Labor aside, I bought a 2.5 liter can of high solids clear for my shop recently at around $320.00, the catalyst runs $190 and reducer is $65.00. It may be enough to do twenty or more of them, but these are minimum amounts that get purchased in the brand I use. We have a cheaper brand of stuff we use, but it is not recommended for use on smaller high quality parts like these, because it just won't look as good. It fits better on the side of a truck that will never see buffing and polishing. | ||
| Bads1 |
I'll tell you guys why not scotchbrite and why the DA did best. It was because the DA was consistent in sanding and your hand is not with scotchbrite. We found that if not just right.... you'd see the fine scratches even through the clear. No argument here. Do it however you want. I'm just trying to help the original poster out. | ||
| Etennuly |
I have a Hutchens DA with a hook-it pad, I could see using that with 800 grit and water. It gives a really nice even surface. I have done a lot of Corvette stuff with that. Usually don't get that out for smaller projects though. |
