NC vs Acrylic Lacquer

[durwood]

The flating agent varies in name depending on brand, usual names are flatting or matting agent or base.

Do you want to bet on the price?

Normally auto/aircraft and marine paints have a premium price compared top other paints.

Our paint was bought under Govt contract and the price still was way above retail for industrial lines.

[Lignum]

Durwood, i get 4 Ltr of auto lacquer from Super Cheap for around $90 (less 20% on sale days) is that good or bad?

[martrix]

Awesome advice Durwood, thanks for the info. I think I will stick with the Auto Acrylic lacquer now. Haven't bought it for a while but I think it is similarly priced to say a Mirotone Pre-cat lacquer, I was just never sure if it was suitable for timber. Makes sense about being more durable and resistant to UV as it is designed to be almost always exposed to the sun, and its crystal clear to boot. People would be mighty pi$$ed if their car started to turn yellow after 6 months out of the showroom .

I assume it is also flexible enough to move with the timber during expansion and contraction? It must be because I know it doesn't dry as hard as 2-pac and I have never had any problems with the 2-pac finish cracking on a table top, cheers.

[durwood]

Hi Lignum and Matrix,
The super cheap lacquer would be OK for general wood work I personally wouldn't consider it for a car unless it was an old bomb. The top grade lacquer is about 30-50% more in price.

The auto paint is very flexable just look at a pranged panel on a car next time it really has to be crunched up to crack.

The normal test is usually to bend it around a 1/4 inch rod without fracturing. You can also add flexing agent to it, that has to be done on very flexible plastic parts.

[silentC]

Straight answer time then. It's a piece of furniture that will be in a bedroom. I've coved the panels tonight and want to start finishing them tomorrow. We got to 19 degrees today. I've got a brand new bag of shellac flakes and some 95% metho. So do I go with the shellac and wax, or do I buy some auto lacquer?

[echnidna]

Use the shellac , you can always overcoat with lacquer for better moisture protection

[echnidna]

btw Lignum, get a price for 20 litres of furniture lacquer,
I think you might be surprised.

[durwood]

Go the shellac, both shellac and lacquer will react pretty well the same in the same temp

[martrix]

Hi Durwood, can you use automotive primer or HiFill as a sealer on MDF to then overcoat with Auto Acrylic? I would like to have a play with some acrylic Candy's.

[durwood]

Hi Matrix,
Yes you can no problem, MDF has a waxy surface so its a good idea to give it a good wash with some Wax & grease remover or thinner first.

Just do a small area at a time wet it with one rag soaked and straight away wipe with a clean cloth.

If you are only playing around spray on the primers or if you intend doing something important thin the primer down more and brush the first coat on then spray the rest. You shouldn't need more than 3 coats of primer.

Do you know what to expect with candy colours?

[silentC]

I had a play with some lacquer yesterday. He only got in high gloss (forgot to tell him I wanted 50&#37 so it's not the finish I want for the current project.

I used the 2.0mm set up on the gun. I turned the air flow right down and opened the needle right up. I only waited until it was touch dry (a couple of minutes) rather than the 10 minutes recommended on the tin. It seemed to go OK but I got two problems:

1. Cover was a bit patchy when you look at it sideways into the light. But I think that was poor preparation. It has long streaky 'holes' in the surface that follow the grain.

2. When the last coat dried I had some pin-head sized air bubbles. What causes that?

[echnidna]

did you rub back between coats.
pinholes can occur if the last coat hasn't cured properly

[silentC]

Nope didn't rub back at all, just sprayed several coats one on top of the other. Was just a test panel to see what it would look like. Maybe I didn't leave it long enough before the last coat. But it was actually a bubble or blister in the finish, as though air was trapped, or some sort of gas formed between the layers.

I think the streaky patches were because I didn't sand and seal properly. It looks like the finish has soaked in along grain lines, rather than a solid glassy film.

[bitingmidge]

Give it a quick LIGHT dusting with thinners, and report back!

Cheers,

P

[silentC]

Righto!