Author Topic: Paint Gurus, I have questions  (Read 714 times)

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Offline denward17

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Paint Gurus, I have questions
« on: April 06, 2023, 03:53:28 PM »
 I have a set of Franken's side covers that are raw.

Pretty sure I will end up painting them myself after visiting a paint shop today.

Would the correct procedure be:
1-Scuff surface
2-Spray Adhesion promoter
3-Sand before primer?
4-Primer, scuff up and clean, and add another coat of primer
5-Scuff up, clean and shoot paint
6-Scuff up after paint for Clear coats?

Thanks for any info....

Offline Alan F.

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Re: Paint Gurus, I have questions
« Reply #1 on: April 06, 2023, 03:57:29 PM »
#5 seems unnecessary, I welcome expert opinions.

Offline denward17

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Re: Paint Gurus, I have questions
« Reply #2 on: April 06, 2023, 03:58:58 PM »
#5 seems unnecessary, I welcome expert opinions.

Which part?  The scuffing before paint?

Offline Alan F.

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Re: Paint Gurus, I have questions
« Reply #3 on: April 06, 2023, 04:03:15 PM »
Yes, I'm no expert but such a thin layer may not need scuffing before clear is applied.
It would be very easy to sand thin spots.

Offline denward17

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Re: Paint Gurus, I have questions
« Reply #4 on: April 06, 2023, 04:13:46 PM »
Yes, I'm no expert but such a thin layer may not need scuffing before clear is applied.
It would be very easy to sand thin spots.

Oh I see, you mean #6, scuff up paint before clear coats.

Offline Alan F.

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Re: Paint Gurus, I have questions
« Reply #5 on: April 06, 2023, 04:36:01 PM »
Ah you're right, I'm polluting your thread!

Offline WideAWAKE

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Re: Paint Gurus, I have questions
« Reply #6 on: April 06, 2023, 07:55:06 PM »
It will all depends on how you plan to paint them (solid color, multicolor, pinlines etc..) and what you  paint products you use.



Offline Mark1976

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Re: Paint Gurus, I have questions
« Reply #7 on: April 06, 2023, 09:25:40 PM »
   Ok, you need to determine what kinda of paint you're going to apply (lacquer,  enamel, urethane), different paints require different preparation. Are you going to shoot rattle can paint, or buy a hvlp gun and shoot your own, either is a completely satisfactory way. Once you outline that we'll be able to determine the materials and method to prep and apply color and then a clear coat. Its not any more difficult than putting the topend on your bike, if you can do that,  applying color and clear coat will be a piece of cake.
Start with the end in mind...

Offline denward17

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Re: Paint Gurus, I have questions
« Reply #8 on: April 07, 2023, 04:27:55 AM »
Plan on getting an auto parts store to mix paint in aerosol spray cans, eurothane.

Offline Mark1976

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Re: Paint Gurus, I have questions
« Reply #9 on: April 07, 2023, 08:17:49 AM »
   Metallic or straight color?
Start with the end in mind...

Offline denward17

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Re: Paint Gurus, I have questions
« Reply #10 on: April 07, 2023, 09:52:07 AM »
Straight color.

Offline Mark1976

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Re: Paint Gurus, I have questions
« Reply #11 on: April 07, 2023, 11:19:49 AM »
   I was always taught, "your paints only as good as whats underneath it" so your prep is really what makes the rest of it stand out. Urethane prep is similar to lacquer prep, its a little more detail oriented. Have a clean (grease and oil free) location to do all your work, cleanliness and patience are your friend here. I'll assume since you have new covers, there's no damage at all to them.
   Start with a clean cover, wash with warm water and soap (dish soap is fine), I wet sand just about everything thing, (you can dry sand if you choose) so start with a bucket of water and 320-360 grit wet dry paper (3M, Norton), you can add a few drops of soap to the water if you'd like, it'll help keep your paper from sticking and packing as you sand. If you can, find a small thin sponge to wrap your paper around, wet it down and carefully sand the surface till you have a uniformly dull surface, no shiny spots. We're not sanding oak so don't bear down on the paper, its a light gentle process. Your preparing for primer, creating a base for good adhesion, if you have any imperfections or blemishes they can be addressed now.
   Once you've got your covers sanded, clean 'em again, and wipe down with clean dry cloth (cotton preferably, but a high quality paper towel is fine as well). Now you can apply your primer. If your shooting a dark color use a dark primer, dark gray (black) or red oxide are my preferences.  Apply 2 possibly 3 coats, leave several minutes (3-5) between coats, this will give each coat time to properly adhere and dry as well as minimizing the possibility of runs in your primer.
   Once that's done, leave it alone till the next day. Rattle can primers are always slow to fully dry. Patience...
   Now, once its fully dry you can inspect the primer surface, looking again for any imperfections. If you've done it right there shouldn't be any and now you can prep for your color coat. Again wet sand the surface uniformly with 600 grit this time around, keeping in mind that you're only sanding it enough to create a smooth blemish free surface. Stay off off the edges and corners as your going to sand thru to your base, and you don't want that. If you do you can always apply primer again, but the edges and corners I do dry and carefully,  think doing this in a, one and done process.
Once you get that far, let us know.  Then you can shoot your color and clear coat.
Just my 2 cents.
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Offline BenelliSEI

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Re: Paint Gurus, I have questions
« Reply #12 on: April 07, 2023, 12:21:00 PM »
Excellent advice above. I’m NOT a painter but I’ve learned a “tac rag” is really useful for cleaning off dust, just before starting.

Offline Mark1976

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Re: Paint Gurus, I have questions
« Reply #13 on: April 07, 2023, 02:27:08 PM »
   Just a side note when sanding, straight line sanding, any direction is fine, do not sand in circles. The sponge or whatever you choose to use to wrap your sand paper around (small rubber pad) is to keep you from using your finger tips and creating an on even surface. Sanding blocks are just too big and long and rigid in this situation so you'll need improvise to get a flexible block that can follow the contour of the cover. I like a sponge as it holds water and suits the light touch you'll need to keep from sanding thru the primer.
Start with the end in mind...

Offline denward17

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Re: Paint Gurus, I have questions
« Reply #14 on: April 07, 2023, 03:09:49 PM »
^Thanks for the tips Mark.

Offline denward17

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Re: Paint Gurus, I have questions
« Reply #15 on: April 14, 2023, 07:35:15 AM »
As a follow up, I got an auto parts store to mix some paint that was close to the Alpha Candy Red (it was paint code 3Q2 from Toyota).  I knew it was not an exact match but very close, and looking at paint chips compared to my tank it was just a little lighter.

Anyway, I used the aerosol can I quickly discovered it was appeared to not be mixed correctly, it was too dark and more purple.  The spray can nozzle also had drips that caused some issues as well.

Discovered that my finish work was not desirable either.  So I am stripping the paint and starting over.

I will probably end up just dropping off the side covers to a paint shop.

Offline Rosinante

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Re: Paint Gurus, I have questions
« Reply #16 on: April 14, 2023, 08:01:48 AM »
I might chat with the folks at my local auto paint store.  They are routinely helpful.  Auto paint is complex.

Ideally of course, you would use a two-part paint.  But that would rule out the rattle can delivery system.  When I use rattle can paint, I warm the can before shooting.  I put it in warm water for a bit.  Pretty warm, actually, just not scalding.  Shake much, shake often.  Put the paint on in a mist.  Multiple thin coats are your friend.

But....I have little experience with paint schemes where there are multiple different layers.  Like flakes and fancy undercoatings and translucent top coats.  My rattle can experience has basically been only opaque paints.

So....begin by stripping to ensure there is no wax or grease or whatever.  Like the release agents that manufacturers use to get parts to release easily from the molds.  Wax and grease remover.  The auto paint store has that.  They also have lint-free paper towels.  (as an aside, they also have the degreaser I greatly prefer over the kerosene-based stuff).

Primer that is made to stick to the plastic.

Sand after each step, but here you are mostly sanding to get smoothness rather than sanding to get profile.  Like 2000 grit.  Wet sand.  Paint does not "fill" anything.  It only highlights whatever underlying problems exist.  strip clean between each coat also. 

Obviously, a paint shop would do a great job.  But spendy.  I think you can do it, instead. 
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Online newday777

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Re: Paint Gurus, I have questions
« Reply #17 on: April 14, 2023, 08:08:18 AM »
As a follow up, I got an auto parts store to mix some paint that was close to the Alpha Candy Red (it was paint code 3Q2 from Toyota).  I knew it was not an exact match but very close, and looking at paint chips compared to my tank it was just a little lighter.

Anyway, I used the aerosol can I quickly discovered it was appeared to not be mixed correctly, it was too dark and more purple.  The spray can nozzle also had drips that caused some issues as well.

Discovered that my finish work was not desirable either.  So I am stripping the paint and starting over.

I will probably end up just dropping off the side covers to a paint shop.

What color is the primer you used Dennis?
Stu
Honda Parts manager in the mid 1970s Nashua Honda
My current rides
1975 K5 Planet Blue my summer ride, it was a friend's bike I worked with at the Honda shop in 76, lots of fun to be on it again
1976 K6 Anteres Red rebuilding project, was originally my brother's that I set up from the crate, it'll breath again soon!
Project 750s, 2 K4, 2 K6, 1 K8
2008 GL1800 my daily ride and cross country runner

Prior bikes....
1972 Suzuki GT380 I had charge of it for a year in 1973 while my friend was deployed and learned to love street riding....
New CB450 K7 after my friend returned...
New CB750 K5 Planet Blue, demise by ex cousin in law at 9,000 miles...
New CB750 K6 Anteres Red, to replace the totaled K5, I sold this K6 at 45k in 1983, I had heavily modified it, many great memories on it and have missed it greatly.....
1983 GL1100A, 1999 GL1500 SE, 1999 GL1500A

Offline denward17

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Re: Paint Gurus, I have questions
« Reply #18 on: April 14, 2023, 08:23:30 AM »
^It was a Dupli-color engine primer I had as spare.  It was medium gray.