Yam RD 250 Paint Thread

thank you!!cant wait to try it again and now a little bit wiser !!

I would add that you determine what the manufacturer says is the right time window for adding the first clear coat. In the main, you would do so right away as Maritime suggests, just saying that since you are using all one manufacturer, do whatever they suggest.

Think I suggested previously to use official degreaser (often called silicone and grease remover) from an auto paint supplier. Sorry to see you have learned the hard way how important the correct chemicals can be (sounds like the Duplicolor rep is right on the money), but you discovered it on a trial part, so be happy! Bite the bullet and go get a gallon can of the real thing. Only about $20 US where I live, so it is not that bad. A gallon is, well, nearly a gallon more than you need, but it is good peace of mind, and you can use it for lots of other tasks, including cleaning less important parts like brackets for a quick but now more high performance paint job. Another good reason to use it is that silicone is unaffected by lots of other (even very aggressive) cleaners, so a cleaner made for silicone is really valuable. There is also a technique to using it too - think I also promoted it previously. Yea, it IS that important. Easy to scoff at a lot of this - until you have a problem and wish you took the extra few minutes and pennies!

And at the risk of harping, I think I also previously recommended a very good technique for shooting clear. Of course it can't apply to every paint, but I would bet the 2K in a can is not so different from the pro stuff. I learned it from guys that actually know what they are doing, so try it out!

thanks mobius!your advice is always precious and interesting to read!

so things get more serious i have to plan buying paint:
i split up the parts into 2 sections in order to know what i will need to buy:

SECTION 1:
1K PRIMER Dupli Color ,Dupli Color Colour,1K Clear Dupli Color-->DECAL-->2K Dupli Color

Stock seat tail (Plastic)
Custom Epoxy tail (Epoxy Resin/Mat)
Side stripe panels of stock seat (Steel)
Side Electrics Panel (Plastic)
Front Fender (Steel)
Hlight Bucket (Steel)

SECTION 1:
2K FILLER/PRIMER Dupli Color ,Dupli Color Colour,1K Clear Dupli Color-->DECAL-->2K Dupli Color

Gas Tank (Steel)
Oil Tank (Steel)

now i need to calculate how much primer et cetera i will need.do you guys have any rules by thumb?400 ml normally stands 0,8 square meters...

Question:

Is there any difference between normal dupli primer (it says anti rust primer on the can)and dupli color plastic primer?

Can i use the rust primer also on plastics?
The plastics are quite rigid,my epoxy seat is hard too.

Plastic primer is called Adhesion promoter and is different. I actually makes the plastic surface sticky to create a bond with the paint better, regular primer won't do that on plastic. That being said I have painted sidecovers with regular paint and primer and had it work just fine.

Same here.i primed the side cover and the epoxy seat with 'anti-rust primer' and it worked fine.
Just wanted to ask if i should prime the plastic differently then the steel parts.
My plan is to prime all partd except for the gas and oil tank 1K.
Gas and oil tank will be epoxy primed.

Maritime said:

Plastic primer is called Adhesion promoter and is different. I actually makes the plastic surface sticky to create a bond with the paint better, regular primer won't do that on plastic. That being said I have painted sidecovers with regular paint and primer and had it work just fine.

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Adhesion promoter and and plastic primer are 2 different things. Plastic primer is actual primer with a different blend of chemicals specifically suited for bonding to plastic. Adhesion promoter is a clear solvent that is used to prep plastic for application of regular primer. And adhesion promoter doesn't make the plastic "sticky", it opens the pores of the plastic to help aid in the chemical bond between the plastic and primer.

The pics you posted looks like severe dirt contamination. Did you use a tack cloth at all? I noticed the one thing you leave out of every one of your steps is tack clothing. You'll never get a smooth surface if there's a bunch of crap on it. And when you wiped down your painted surfaces with brake cleaner, you were basically wiping them with fast evaporating lacquer thinner. The only time you should use wax and grease remover is at the very beginning before you start your body work and prep, after body work, before paint, and the rare occasion that you might spill anything on the surface or otherwise contaminate it. You should also blow dry or wipe the surface with a clean microfiber immediately after using W&GR so it doesn't soak in causing a delayed contamination.

Thanks octane for your thoughts and wisdom!

Actually i use the tack prep method.the contamination was def chemical,due to the brake cleaner,the dots and spots were extremely regular looking like a rash and only on the part of the paint were i use it deliberately.
Wont do that again
My question:should i use adhesion promoter on my vinyl decals before i spray the 2K on it?

You do not need any sort of adhesion promoter for any aspect of painting your RD. Generally I would say that you do not need any sort of special plastic primer for the plastic parts as the type of plastic (I believe it is just the right side cover?) will take paint very well, but since I can't claim to using the same primer you are using I can't speak to it. The best advice I can offer is to get a high quality epoxy primer and use it on everything first prior to body work. Solvent based primers are much more dedicated to what they are for, but if you are using spray cans it should say if you can use it on plastic. Don't complicate your work thinking you need to add materials you do not need and that will offer zero improvement and the potential for complications.

As a rule there are two means by which you can attach your paint to your project. The first is chemical, where the paint bites into the material it is place over by chemical bonding or by slightly dissolving it. The second way is to mechanically interlock into the surface, in which case sanding is required to create a rough surface to grab on to. It would appear that you do not need any intermediary layer to enable you to accomplish either.

Octane is correct in stating that you shouldn't need to use wax and grease remover after you start painting. However, this is ONLY true if you have a situation in which you paint more or less continuously until no more painting will be done. If you handle your parts in any way at all after application of any material, it is a very wise precaution to meticulously clean and tack everything. Oils in your skin are dreadful contamination for new paint, and even with gloves, you can not be sure of not leaving behind something bad. You will be severely handling your parts (and probably using masking tape to help with alignment) when you apply the graphics, and you should meticulously clean everything before you finish the clear. Go easy on the decals with the cleaner - after all, it is a solvent. Learn how to use the cleaner!! Getting a paper towel wet with degreaser and just wiping down the surface won't do - that is just smearing contamination around. Use lots of towels and wipe on degreaser with one and wipe it off clean and dry with another. Always wipe one pass, flip over, throw away - both towels. Start over on the next area. Yes it takes a million towels.

Thank you!
I 'll stick to that!!

Yeah, I don't think that was ever clarified. You only need to use adhesion promoter on bare plastic. If the paint already has a good bond, you just need to sand and prime. If the paint is flaking or peeling, then you need to strip and start from scratch. And you can use W&GR on base coat, but only if you need to and use it sparingly. really, the only time I use W&GR on base coat is when there is bad dirt in my paint and I need to wet sand it out. At which case I sand with 1000 and then lightly wipe it with W&GR, blow dry, and tack cloth, then back to base coat.

High On Octane said:

Yeah, I don't think that was ever clarified. You only need to use adhesion promoter on bare plastic. If the paint already has a good bond, you just need to sand and prime. If the paint is flaking or peeling, then you need to strip and start from scratch. And you can use W&GR on base coat, but only if you need to and use it sparingly. really, the only time I use W&GR on base coat is when there is bad dirt in my paint and I need to wet sand it out. At which case I sand with 1000 and then lightly wipe it with W&GR, blow dry, and tack cloth, then back to base coat.

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Yep sorry to confuse I had sanded all my plastic bits to bare plastic so the promoter was required. When I have done other parts that had good paint already I just sanded the paint to get tooth and went from there.

Is there a trick using tack cloth?
Bought professional tack cloth from presto.the manual says to slighlty massage the piece,no excessive rubbing.
I had the most problems at my test piece with tiny lints that were enclosed by the paint,altough i used the tack cloth.
It was plastic so maybe there is an electrostatic gravity pulling the lints to it.
Didnt were a full plastic suit yet so maybe this was a source where the lints came from.

No trick. They are sticky and seem like they would have to leave behind something dreadful, but don't worry. I just very lightly run a somewhat wadded up cloth over things immediately before I paint, and very lightly blow some air over the parts from the spray gun - though I realize you can't do that with a can. For me I get the cleanest work focusing on keeping the area very quiet and still. I clean up the shop and cover everything I want protected from over-spray, set everything up exactly how I am going to paint, get out all the tools and materials I will need, and make sure I am absolutely ready in every way. Then I leave the shop closed up and undisturbed for a few hours. When I come back, I am careful to disturb as little as possible, tack off the parts and start painting. I have never been a pro painter myself, but I used to own an upscale paint and body shop and I get cleaner work this way in my embarrassingly filthy home workshop than we generally got in our very fancy pro spray booth at the shop. Most contamination comes from trash off of the thing you paint blown off from spraying the part - important for cars, not really an issue for well prepped bike parts. It can come from the compressed air - not an issue with spray cans (they have other problems like spitting etc) so it is important to filter the compressed air. It can come from the paint itself so strain and filter the paint (again, not an issue with cans). You are right - All kinds of problems are related to the painter. Clothing, hair, dirt from the floor, shoes, etc. Especially bad because the painter is the only thing moving around which tends to shake loose any existing contamination. You have some degree of control over all these things, but even in a very still room there are little specs floating around in the air, and it can take a very long time for them to settle via gravity and are easy to stir back up. To a degree, spray cans have an advantage as you have no air line. Dragging the line around on the floor has to be bad! In the end, it is a losing battle - all you can do is to minimize the problem. That very obvious speck in your new paint is very likely too small to find if you try to dig it out. The paint massively amplifies the actual size. Fortunately the color you are using will hide most anything once you sand and polish the finished parts.

jpmobius said:

No trick. They are sticky and seem like they would have to leave behind something dreadful, but don't worry. I just very lightly run a somewhat wadded up cloth over things immediately before I paint, and very lightly blow some air over the parts from the spray gun - though I realize you can't do that with a can. For me I get the cleanest work focusing on keeping the area very quiet and still. I clean up the shop and cover everything I want protected from over-spray, set everything up exactly how I am going to paint, get out all the tools and materials I will need, and make sure I am absolutely ready in every way. Then I leave the shop closed up and undisturbed for a few hours. When I come back, I am careful to disturb as little as possible, tack off the parts and start painting. I have never been a pro painter myself, but I used to own an upscale paint and body shop and I get cleaner work this way in my embarrassingly filthy home workshop than we generally got in our very fancy pro spray booth at the shop. Most contamination comes from trash off of the thing you paint blown off from spraying the part - important for cars, not really an issue for well prepped bike parts. It can come from the compressed air - not an issue with spray cans (they have other problems like spitting etc) so it is important to filter the compressed air. It can come from the paint itself so strain and filter the paint (again, not an issue with cans). You are right - All kinds of problems are related to the painter. Clothing, hair, dirt from the floor, shoes, etc. Especially bad because the painter is the only thing moving around which tends to shake loose any existing contamination. You have some degree of control over all these things, but even in a very still room there are little specs floating around in the air, and it can take a very long time for them to settle via gravity and are easy to stir back up. To a degree, spray cans have an advantage as you have no air line. Dragging the line around on the floor has to be bad! In the end, it is a losing battle - all you can do is to minimize the problem. That very obvious speck in your new paint is very likely too small to find if you try to dig it out. The paint massively amplifies the actual size. Fortunately the color you are using will hide most anything once you sand and polish the finished parts.

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I experimented a little bit when i painted the side cover by taking a lint free rag, soaking it in water and putting it under the elevated piece which was painted.i had the feeling the the wet rag (not dripping wet) "slowed" down or even "ate up" the overblow of the paint that was hitting the piece.
still thinking about hanging the pieces from the ceiling with steel wire to ensure that I dont move any particels around the object and eclosing them into the paint...
this way the particles in the air would be the only way to contaminate...

just for my interest: you already stated that i need no adhesion promoter for the plastics,but the vinyl decal manual says yes,do you think the 2K will adhere to the decal with no problem?
is there a different way to apply 2K in comparison to the "normal" 1 K clear coat?

thanks!!

I hang little brackets and parts with wires, but NEVER body parts. The reason is that many small parts are either really easy to paint or the paint appearance quality is not very critical - a voltage regulator bracket for instance. Body parts need to be held down strongly so they have no chance of moving around, both so no damage can occur while painting (which usually takes a while), and so you can control your spraying technique very carefully. I very often actually screw my parts down, often in numerous places, and usually to a wooden stand, one stand per part. That way I can have a stand that positions the part as ideally as possible for painting and be able to shoot all the sides, top and bottom as required. I only very rarely put a part on a flat surface like a table for the very reason you suggest.

I make every effort to NEVER touch my parts with anything once I start painting, but if that is not possible, I never use anything to clean them with except W&GR (wax and grease remover) and "known to not create problems" paper towels. I use plain white no printing "Bounty" brand kitchen paper towels as they make very little lint, contain no chemicals or perfume, don't scratch, and are cheap. Can't say I see anything but bad in using water, unless it is distilled and even then don't think it will do much to remove debris or chemical contamination. However, I do suggest you use distilled water with a single drop of dish soap per 2 or 3 liters water when applying your decals, and wipe them down with pure distilled water (no soap) afterward and thoroughly wipe dry. You will be handling your parts excessively to place the decals, so get some W&GR and some paper towels and after 24 hours clean everything thoroughly but carefully right before you finish the clear! After all the work it took to get to that point you don't want any problems!

I am sure I mentioned previously, my favorite "test" for sticky materials like 2K urethane clear is to touch an area - usually on masking or maybe a spot that does not show and is equally wet as anywhere important with my finger. I usually have a spot in mind when I paint so as to make sure it has the same amount of paint as the important areas. When the paint is still too wet for another coat, it will simply be wet. As it cures, a "spiderweb" will be created as you draw your finger away. If the spiderweb is super long, 50mm or more, maybe wait a little longer to re-coat. I usually wait until I get spiderwebs 8mm or less. No spiderwebs is too long, but as long as the provious coat is sticky you should be ok. Do not apply a "dust" coat! First coat after the decals should be a thin to medium wet coat - thin as possible but wet. You want it thin so it offers the least chemicals to attack the decals, but wet enough so it flows out and does not look dry or bumpy. Let that first coat cure longer that usual so it can protect the decals from the following coats. I wait until there are nearly no spiderwebs. Then I start applying regular heavy coats using the spiderweb test between them. If you get everything right you will be able to have all the coats flow out nice and slick. Keep in mind that most clears, out of most guns ( I know you are using spray can, but likely it will be very similar), even when applied sufficiently wet takes about 5 - 20 minutes plus to flow out so be patient and test spray a junk part first (a good junk part so your test is like your real parts) to see how much is too heavy and runs (wait 10 minutes+ + to see!! 2K clears flow slooowwwly but relentlessly - you must wait!!), or too dry and won't flow out, which is a worse disaster than runs or drips. It is not hard, but does take a bit of practice and experience. In summary, over decals, first coat thin but still wet, max tack up time, then 3 heavy wet coats normal tack time. I know pros that do 2 medium coats and one very heavy as a lost coat, but they shoot paint every day and can push that last very heavy coat right to the edge without too many problems. At the end, it is only important for how much work it takes to sand it slick for polishing. The heavier the coats, the more the paint flows (or runs off!) and the less work to sand it perfect for polishing.

As a rule, too wet is better than too dry, but be patient with your test, and methodically repeat on the good parts once you are happy with your test and you should be fine. Here is why. Too dry will make a very rough surface because the paint is not wet enough to flow out into a sheet. Once it starts to cure, the coats on top of this bottom rough coat will not melt it into a smooth surface, and every additional coat will amplify the texture into some super orange peel. Too wet, and you will get drips and runs.

Regardless, do not worry too much! Both problems are fixable, but carry on and continue painting regardless. Fixing problems relies totally on having enough clear applied so that sanding out the problems does not risk cutting into the base color or decals, in which case you start over, so continue to build up the clear as if everything was perfect. After the clear cures, you can carefully sand out all the orange peel, or drips or whatever, and then either apply more clear or polish it. It is very hard even with experience to tell how thin you are sanding the clear and consequently very easy to sand through it, so knowing you have a LOT of clear is your best safeguard.

And FWIW, Consider having more clear on hand than you expect to need before you start. You will not have time to go to the store for more if you underestimate. If you don't have enough, you will have to be extremely careful sanding before you can add more which is risky. I ALWAYS mix up substantially more clear than I expect to use, and when I look at it I ALWAYS say to myself "what an idiot, I'll end up throwing away all this extra super expensive clear - shit!". Well I ALWAYS end up using it all, and about half the time I end up mixing up a bit more! Of course, it may be I just can't get the hang of estimating my materials properly!

Good information above. The only thing I would say different is flash times between clear coats. I wait longer than when it is in "string" or "spiderweb", as it is too easy to get a run if you spray too wet. Wait a couple of minutes past "string" when it is "tack". "Tack" is when you touch the clear and your finger tip sticks but does not string back. Again, touch an area that is masked or a part of your stand that is close to the edge of the part. Speaking of which, I don't know if it was ever mentioned but you always want to spray past the part you are spraying and never stop spraying in the middle of a panel no matter what.

hey guys!

i´m pretty much trough with painting my parts!!th results are really nice,didnt think it would work that good.
i´m gonna post the pics this week,not a lot of time left this week.

i have a question:

i shot 2K as a last coat,letting it cure now,thought about doing another coat,as a additive protection coat and even more shine (this stuff has already a great shine to it).
how do i prep the cured 2K for another shot of 2K?schuff it with red scotchbrite and degrease?

will another coat (over the 2-3 coats already applied)increase the shine?
thanks in advance!

You can use a Scotch-Brite to prep it, but you will want to nib out any dirt or runs. I would highly recommend NOT using W&GR in between as it may cause some reactive issues. In fact, I've pretty much stopped using it all together except for actual degreasing of stuff. I've switched over to water-based prep solvent. Cleans almost as good and no harsh chemicals to contaminate the surface. I've heard a lot of guys are switching over to Windex, including a friend of mine who paints too.

I would take #600 or finer wet sandpaper and sand out all the "nibs" (trash in the paint) and orange peel. Generally you can just focus on the large areas and forget the very difficult (and risky) to sand corners (like around the welded seam on the tank) with the sandpaper, but you need to at least scuff thoroughly what you miss with the paper 100% with the scotchbrite. I usually use a semi rigid rubber sanding block to maintain surface contours. It is very important to abraid the surface to give the following coat some "tooth" to hang on to as the 2K clear will not chemically react with the cured 2K and bite on very well, which is why you see clear peeling so often - bad prep. If you have any doubt about not sanding through, stop and use the scotchbrite! Extra coats of clear don't actually make your work any shinier, but as a rule you can get a much flatter and more perfect surface by sanding things "flat" and then adding another coat of clear to restore what you sanded off. This may sound pointless, but you will see that afterward the orange peel is less, and will require sanding less material back off for polishing. This is because every coat of clear amplifies the orange peel from the previous coat, and usually after 3 coats the peel is fairly pronounced. Your application tools, viscosity of the material and technique are huge factors, but all things being equal, the more coats the more peel. Sanding things smooth and adding back that last coat leaves you with only one coats worth of orange peel, and is usually easy to sand slick without removing too much.
Opinions vary on the W&G remover. For me, it is cheap insurance. I have never had it react adversely with anything ever, so I use it whenever there is any doubt at all. I use it on all sorts of paint of every kind including cheapo spray bomb paint and never had it cause a problem as long as the paint was dry. That said, it is just my own experience, and as has been mentioned, it is a solvent and maybe it is not so good for some paint out there. (Of course, water is also a solvent!) Sanding usually ends up being a pretty messy job with lots of handling. Lots of potential to contaminate the surface and cause a problem. Cleaning your parts with W&G remover is a fairly quick and easy to control process right before you spray, and is an excellent way to make sure anything that found its way onto your parts has been removed. A quick pass with a tack rag after that and you should get great results!
Certainly correct technique is important with the W&G remover. As said before, clean an area with one wet towel and then remove all the solvent and dry with another. Get more towels and do another small area. You need to dissolve contaminants and then quickly remove them which takes patience and technique. When I was manufacturing paint booths, I was in hundreds of body shops, and commonly saw guys pretty much just smearing W&G remover around and mostly it would just evaporate before they could remove it. I would guess those guys didn't feel the W&G remover provided that much benefit. I owned a body shop of my own back then, and for us, defects were simply not tolerated; Rigid control of every operation and religious attention to preparation is what got us there and EVERYONE was an expert with the W&G remover!
FWIW, I don't know a thing about any water based prep materials as I have never used them, but sounds like a good thing if they work as good as HoO says.

Looking forward to some pics!