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Old 25th April 2006, 05:14 PM   #1
tf1216 is offline tf1216  United States
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Default Re-post: Spraying advice needed *Sorry*

Hi,

Sorry to re-post like this, the original message is located in the "Everything Else" forum

Spraying advice needed

I am about to proceed and head towards the completion of my cabinets. I have a friend who offered to spray my cabinets and I would like some finishing advice.

I would love for my cabinets to come close to the BMW Laguna Seca Blue finish with the high gloss like Jim Salk was able to create. I think I will finish all of the fascias with a type of white, which I am not sure yet.

http://www.salksound.com/gallery-votm-0704.html

Anyone have any advice how to obtain exactly that blue finish?

Thanks ahead of time everyone!!!!
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Old 25th April 2006, 05:44 PM   #2
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Surely you just need a local bodyshop or paint factors to mix you up the BMW colour?
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Old 25th April 2006, 06:20 PM   #3
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Prep, prep, prep.

Make sure that your cabinets are perfectly straight and flat. Sand them to 220 grit using a long sanding block. I'm not sure what to recommend for a sealer, because I usually use PianoLac which is a water based system and you'll be shooting an automotive paint.

Use an automotive primer, wet sand with 320 grit on a block after a few coats start to cover. Wet sanding is exactly what the name implies. With most finishes you dip your sanding block in water (with a couple drops of dish detergent to help prevent clogging) and sand the surface. If you hit raw MDF, stop sanding and shoot some more primer. The water will cause the MDF to expand and the more you sand the worse it will be.

Your friend probably knows about shooting a contrasting color guide coat to help judge when the primer is flat. If using gray primer, mist on a little black and sanding will highlight low spots.

Most likely you'll find a nice blue that comes close to your desired color at an automotive paint store. I'd shoot the white first, mask it and then shoot the blue. Pull the masking tape at the edge while the paint is still wet to allow it to flow out and reduce the size of the junction.

After you have built up a decent film, you'll clear coat all of it. Build up a good thickness since this is what you'll be polishing. Shoot a couple coats, then start lightly sanding with 320 grit after every few coats.

Once you have sprayed perhaps a dozen clear coats, let the paint fully harden. Consult the paint manufacturer, but this could take several weeks. You'll have a nice glossy finish that shows some orange peel on close inspection. Now the work begins.

It will be hard to do, but start wet sanding with 320 grit on a block. Try to keep all sanding in the same direction - move your hand in a straight line. If you go in circles or ovals you're likely to let the edge dig in and make a deep scratch. If your paper starts to clog, replace it. Not only will clogged paper take longer, it makes deep scratches.

You'll now have a dull, scratchy finish and be cursing me. Sand until the surface is very evenly dull and no low spots remain, or at most very minor low spots. If at any time you sand through the clear coat, stop. Shoot more clear, wait for it to cure and start over.

Clean up. It is vitally important to remove all the sanding dust from both the work and the work area before moving up a grit. the sanding process first flattens the surface and then progressively removes the scratches with smaller ones. A bit of large grit will ruin your efforts. I suggest a bit of plastic drop cloth on your sanding table that gets thrown away after each grit.

Sand with 400 grit until the surface is uniformly dull. You'll see that the surface is smoother, but still not shiny. clean up.

Repeat the process with 600, 800, 1000 and 1200 grit. Take your time, spend at least as much on each phase as the previous. Depending on the polishing compound you use you may need to go to 1500 or 2000 grit. At this point you should have a nice satin finish.

Rent a power buffer/polisher if you don't already have one. You'll want a right angle one that looks like a grinder but goes slower. The car buffer/waxers are not powerful enough. You'll need to get a good polishing head - try googling on automotive paint tools.

Polishing will be a two stage process - a course compound then a fine one. Again, clean up between stages. After polishing you may want to use a glazing compound such as Meguiars, then wax with a good quality wax and power buff.

It is a LOT of work, but oh so much better than a gloss off the gun finish.
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Old 25th April 2006, 06:29 PM   #4
tf1216 is offline tf1216  United States
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Wow, thank you guys!!

Those are the types of answers I was looking for.

I admit that the process is even more involved than I originally speculated but this will be fun!

: )
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Old 25th April 2006, 07:26 PM   #5
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Quote:
Originally posted by tf1216
I admit that the process is even more involved than I originally speculated but this will be fun!

: )
Damned right it will be!
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Old 25th April 2006, 11:41 PM   #6
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While I agree with Bob on the primer work, I will say that if you are using automotive paints, do not sand after shooting the color.

I've shot more cars than I can shake a stick at, the key is in the prep of the primer. This is what you need to make look like what you want your finished product to look like.

The base/clear system is made to act as just that, a system. Each step of the system was designed with production lines and body shops in mind, fast dry, brilliant colors and shiny clears.

Once you are to the point of shooting color, there should be no need to sand. The color will lay in very thin coats and cover very well. Two to three coats of color should get you good coverage. Don't waste color trying to thicken the paint job. Color is designed to be just that, color, not a protective layer. You will also notice that the color sprays very easy, it's hard to make the color run unless you are rushing and trying to force coverage.

The clear is the tricky part because you need to spray the clear very wet, almost to the point of it running. Then let it flash for the recommended time and then some and then recoat again. Two wet coats of clear will probably get you where you need to be, a third may not hurt, but no more than that.

Do not sand if you can, the best clear shines when sprayed right any sanding and polishing only dulls the finish. Chances are you will not achieve the perfect flat spray as a first timer so a bit of sanding will be required.

With a flat block and some 600 grit, lighlt sand the clear, all you are after is knocking off any high points. Next move to a 1200 grit. As you sand you will see dull spots and shiny spots, most likely as an orange peel. Don't sweat it and don't try and force it smooth. With a good polisher as Bob described and a foam pad, use a light rubbing compound to bring the clear back to a shine. I've found through the years that 3M Perfect-it II works wonders to smooth out a clear with out getting into the plastisizers that will cause a dull finish. Followed by a lighter compound 3M Finesse-It II which will really bring out a shine. Then wax and enjoy.

How well you do as a first timer will depend on your patience, painting today is more technique than quality tools. I've seen a good painter lay down a fantastic paint job with an old craftsman gun and watched folks with the high dollar Satas ruin a can of paint.

Get a practice piece and learn how the gun shoots and learn how the paint lays.

Oh well, I'm off to the shop. If you want some more info, let me know, paint is one thing I do know.
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Old 25th April 2006, 11:51 PM   #7
Relax is offline Relax  United States
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Thanks very much guys, this thread is a huge help to newbie painters looking for that deep shine.
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Old 26th April 2006, 12:25 AM   #8
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Dryseals has a lot more experience than I do. I've shot a few sets of speakers. Pianolac is different than automotive paint, but I needed a slow run through the grits when I shot automotive to get good results. I'll bet it was mainly my rookie technique, but there you have it.

The 600-1200 grit routine is enough for the smooth finish laid down by a good painter, which I am not. If you have a heavy orange peel, I'd suggest starting coarser and working slowly through the grits. I sand every three coats of clear to keep the size of the orange peel manageable.

Pianolac is high solids, but cannot be laid down as thick as Dryseals is spraying clear coat, hence my high number of coats.

Practice is important. I used less than 1/3 as much base coat the last time I sprayed as the first and for better coverage on the same size cabinet. Practice on a piece of cardboard or scrap MDF that has been appropriately prepped.
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Old 26th April 2006, 11:13 AM   #9
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I'm going to have to give the Pianolac a try, never shot it but it may well be an easier medium to work with than automotive paint. What gun are you using Bob, the gun can make a difference as far as the way the paint sprays. A decent gun for us week end painters can help wonders. I have seven different guns, one is purely for clears and never sees anything else.
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Old 26th April 2006, 11:33 AM   #10
tf1216 is offline tf1216  United States
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Do any of you gents have links to some of your work?
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