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Old 8th February 2006, 11:07 PM   #1
Vikash is offline Vikash  United Kingdom
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Default Cabinet finish - When to buff out?

I'm aiming for my first high/mirror gloss finish. The cabinets have been sealed, primed (18 coats sprayed), and three coats of gloss black sprayed on.

At the moment wet sanding the top coat with 1200 grit results in a matt finish so I wasn't sure whether I need to cut and buff out now, or only after the final clear coat has been applied.

It's gone well so far, I don't want to mess it up at the last stage...
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Old 8th February 2006, 11:15 PM   #2
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Final clear coat? Think again! To get a deep black effect you're looking at at least three or four clear coats, if not more, all rubbed out before the final polish.

Sorry!
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Old 8th February 2006, 11:25 PM   #3
Vikash is offline Vikash  United Kingdom
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Err, yeah I intend to do several clear coats Al I'm just working on the black coat at the moment and wasn't sure whether it would be ok to start the clear coats when the black looks matt.
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Old 8th February 2006, 11:35 PM   #4
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Wipe it over with a damp cloth, and if there are no deep marks or scratches then you're good to go with the clearcoats.
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Old 9th February 2006, 12:12 AM   #5
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I don't see a need to go all the way to 1200 grit before the final coat. I usually do 320 between coats, 400 before and after the last black, then 320 on the clears and 400 before the last clear coat.

It is VERY important to get to the point that the surface is uniform before proceeding to the next grit, as Al said. I'd go a step further and say be sure that the sanding marks are all in the same direction. My hand sanding tends to go in ellipses, and is shows through the topcoats. Also be sure to clean the surface thoroughly between grits. A piece of 400 grit sludge will ruin your 600 grit efforts in a heartbeat.

Depending on your spraying technique, you'll probably want even more clear that Al suggests before rubbing out to ensure that you don't rub through the clear.

Be sure to let the finish fully cure before buffing out. (several weeks for lacquer) Depending on the compound you use, you can stop at 1200 grit. If you go to 1500 or 2000 you can skip the rubbing compounds and go straight to polish. Take a look at 3M's automotive rubbing/polishing compounds. Manzerna also makes excellent compounds. I used their polish sticks on a domet flannel buff chucked in a drill with excellent results.
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Old 9th February 2006, 12:23 AM   #6
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Quote:
I don't see a need to go all the way to 1200 grit before the final coat. I usually do 320 between coats, 400 before and after the last black, then 320 on the clears and 400 before the last clear coat.

It is VERY important to get to the point that the surface is uniform before proceeding to the next grit, as Al said. I'd go a step further and say be sure that the sanding marks are all in the same direction. My hand sanding tends to go in ellipses, and is shows through the topcoats. Also be sure to clean the surface thoroughly between grits. A piece of 400 grit sludge will ruin your 600 grit efforts in a heartbeat.

Depending on your spraying technique, you'll probably want even more clear that Al suggests before rubbing out to ensure that you don't rub through the clear.

Be sure to let the finish fully cure before buffing out. (several weeks for lacquer) Depending on the compound you use, you can stop at 1200 grit. If you go to 1500 or 2000 you can skip the rubbing compounds and go straight to polish.
This dude knows his stuff!

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Old 9th February 2006, 12:31 AM   #7
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Thanks Mark. Learned it the hard way.
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Old 9th February 2006, 09:44 AM   #8
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Yup, loads and loads of coats of lacquer - I apply up to 10 fairly thick coats if I'm painting somthing important.

I have found flatting the penultimate coat of base but not the final coat gives better results provided the final base coat goes on well and dries flat and shiny.

I apply about 5 coats of lacquer, flat them after a week of so, apply the final 5 and polish out the surface a week or so later.

My tips are... Place the cans in water at about 40 degrees for 20 mins before spraying and I use a bit of carpet in a plastic bag as a sanding block to ensure even pressure across the surface of the sandpaper.

Be careful of the edges when sanding The number of times I went through an edge or corner is unbelieveable...

I learned the hard way too Some of my early efforts were shockingly bad
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Old 9th February 2006, 10:35 AM   #9
dnsey is offline dnsey  United Kingdom
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And don't let anything touch the surface until the finish is fully hardened.
I put a lot of work into giving a front panel a piano black finish. Several days later, when the laquer was completely hard to the touch, I placed a light aluminium knob on it, just to see how it would look, and fogot about it overnight. By the next day it had sunk into the laquer, leaving a prominent ring mark
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Old 9th February 2006, 10:51 AM   #10
Vikash is offline Vikash  United Kingdom
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This is the stuff I will be using for the clear coat: http://www.paints4u.com/ProductDetai...productID=3166

I've used the same U-POL stuff for the primer and basecoat.

What is the time required to fully harden? I've also been sanding down after only letting it dry overnight, or sometimes less.

Bob, I've been using only 600 grit directly after every four coats of primer, and I just tried going straight to 1200 after applying three base coats. It gives smooth results fairly easily and avoids digging back into the primer coats.

I tried buffing out a small patch after sanding the basecoat to 1200 grit using automotive rubbing compound, and the results were excellent. I'm happy with the finish there, but I assumed the clear coat is then applied primarily as a protective layer. Is this right?

I also wondered whether clear coating the matt finish base coat (sanded 1200 grit) would bring back the full gloss once the clear coat is applied. I think PM has answered this one.
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