High Gloss Piano Black Finish on wood

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Enigma_2k4

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In order to not hijack this thread I'd like to move the discussion re. getting a high gloss piano black finish over here.

JimGore (Ian) was kind enough to take the time to relay his extensive knowledge on the subject to us and I am going to repeat that for the betterment of all here:

There is only one way to get the "high gloss piano" finish, and I can summarize it with two words:

*  Patience
*  Preparation

You are correct correct in saying that it is a hard composite material which is used.  It is called 2K automotive paint.  Because it is mixed with a catalyst, it is in essence a composite material with pigment in it.

To get MDF to a high gloss finish is easier than real wood because it doesn't have grain.  The process I follow for MDF is as follows:
1.  Seal the MDF.  Use wood glue mixed in a ratio of 1:1 with water for the end grain - paint this on with a brush.  You can do the same with the rest of the cabinet if you want.
2.  Sand the sealer flat.
3.  Repeat steps 1 & 2 until completely sealed and perfectly smooth.
4.  Hook up the spray gun and compressor.
5.  Shoot two thick and solid layers of 2K Medium Solid (MS) primer.  This primer allows you to "build" up, and can fill small holes, etc.
6.  Sand primer flat.  Very important - you cannot do water sanding - the primer is not a sealer, and will absorb the water.
7.  Repeat steps 5 & 6 until the surface is perfectly smooth and has no (or as few as you can live with) defects.
8.  Shoot one very light coat of the same primer.
9.  Scuff sand with 800grit sandpaper.  This light sanding is the key for the following coats.
10.  Clean the entire cabinet down with a damp cloth to remove dust.  Leave to dry for a couple of hours in a warm area.
11.  Mix up your paint, catalyst & thinner, then strain using a paint strainer.  This removes any dust or other particles in the paint.
12.  Shoot 3 light coats of paint.  Many people get things horribly wrong here because they try to get solid coverage too quickly.  Rather do 10 light coats than 2 heavy coats for the same coverage.  Some experience in spray painting helps alot here, so try it on some scrap wood first if you have never done it before.  Each coat of paint must be light enough so that it doesn't run, but heavy enough so it is "wet".  If you spray too light a coat, the surface will have a grainy feel (dry).  If you spray too heavy a coat, you will get orange peel, or worse still, the paint will run.
13.  Leave to dry for a couple of hours, then wet sand with 800 - 1000 grit paper, giving special attention to any problem areas.  After, wash surface down with clean water & leave to dry.
14.  Repeat steps 12 and 13 until you get complete coverage, and the surface is satisfactory.
15.  One of the most important aspects in a "piano" finish is the clearcoat.  Because there is no pigment (you can't see what you are doing beyond the first coat, so you must go on gut feel and instinct), it is also one of the most difficult to get right.  Shoot a minimum of 3 coats of clearcoat, using the same methods described in steps 12 and 13.  The more clear coats you put on, the more "depth" you will achieve in your final finish.
16.  When you are happy with the finish on the clear coat, then lightly water sand the entire surface with 1200 paper and wash clean after.
17.  Shoot the last coat of clear.  It will be a very light coat, and needs to dry as slowly as possible to get the highest shine.  The slower drying allows it to smooth out more.  This means using slow catalyst, and slow thinners.
18.  Leave the cabinets for at least 2 weeks without doing anything else to them.  this allows the paint to cure, and any solvents left in the finish to evaporate.  The process is called "post curing".  The longer you wait, the harder the finish will become.  The harder the finish, the easier it is to polish and buff.
19.  Hand polish in the same way you would your car.  It is car paint after all, so go for it.  Machine buffing is not recommended because it will eat through the corners of your speaker cabinet.

For solid wood, you obviously want to see the grain, so you cannot use primers, etc.  The process is the same as the above, from step 15 onwards.

1.  You will need to fill the grain.  This is time consuming and can be very frustraing because it can take long, depending on the kind of wood you use, and how fine or coarse the grain is.  The general idea is to put down a layer of clear finish, let it cure, then sand it down to the wood.  The finish will remain in the grain.  Each repetition will fill the grain more and more, until it the entire surface is level and flat.  I like to use a dark pigment in the finish I use to fill the grain because it gives nice contrast between the wood and surrounding grain pattern, thus highlighting the grain.
2.  After that, continue from step 15 above.

Now, after all that I got my brain juices flowing a bit and I was curious. So off I headed to my local bulders warehouse and I purchased a small tin of Plascon black high gloss enamel. I was on a mission to see just what I could do without a spray gun!

I went home and went thru my off cuts and tried it on:
1. MDF
2. SA Pine
3. White Melamine

And I must admit I was very surprised by the results.

First off I triued to smooth them all off a bit with some 100grit sandpaper I had lying around. I know it's not nearly as smooth as it should be but I didn't care as I was testing things out.

The MDF soaked up alot of the paint and looked dull after 1 coat, however, after a second and third it really looked the part. However, the cheap brush I used showed up all the brush strokes which sucked.

The SA Pine showed the grain thru nicely and looked very similar to the black ash veneer you get on alot of pre-fabricated beds, cupboards, etc at some shops which is cool. My bed is done in this finish and now finally I can build some side tables that will look the part.

The Melamine surprised me the most. After one coat it was incredibly reflective and looked pretty good. However, as I noticed melamine has these very small little "dimples" in it which show thru on the final product. Also, my brush strokes were still visible, with a sponge or roller I could get a much better effect I think. Also, there were small little "bubbles" visible on it, and I guess that's because I applied the first coat too thick.

I have some questions that I am hoping can educate me and fix some of my complete lack of experience a little:
1. The paint was quite thick, and I'm certain that if I thinned it out a bit then I'd not get the visible brush strokes and it would show less imperfections, but it would need more coats. What could I mix the paint with too do this?

2. Would a sponge or roller work better then a brush? Or am I just using a really crappy brush?

3. Can I sand the paint a bit after each coat to smooth it out? I guess I'd need something around 400-800 grit for the best results.

4. The MDF was really thirsty. What's the best thing I can do to prime it a bit and seal off the wood before painting?

5. Could I do a clearcoat afterwards to really seal it off and give a lekker sheen? If so what product should I look for?

I did see a nice compressor 50L for R1000 at builders warehouse but that's a little too much for my budget at the moment.
 
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