What size of metal flakes you use?
S , M , XL or XXL?   

How many flakes i need for 1 Lt clear lacquer?

I used 400 micron flake when I had a play with a paintbrush 

http://www.beachbuggy.info/index.php/topic,7580.msg78069.html#msg78069

Do you have the means to experiment?   

The results you get vary greatly. From the tiniest of sparkle to dots and splodges.

use "high pressure -low volume" compressor and gun with a medium tip and adjust the pressure and fan size and spray onto a large piece of heavy cardboard. This way you will get some idea of the effect

Keep in  mind the heavier each coat you apply the more flakes you lay down.

The one thing to focus on is use the same mix for the entire vehicle. Keeping it well agitated.

When metallic first arrived on the scene I was advised to watch out for mismatch. That is to say don`t try to match something already painted. Do the lot in the one go so that as the flakes settle as the solvent flashes off they settle in an even manner as possible

I have sprayed many a wing, door panel etc with paint from a dealer to find that when applied and say looking at the panel straight on it is a good match. Stand in front and look down the side an it stood out like a sore thumb.

There is nothing like giving it a go to find what suits you.

The traditional old school size of flake when moulding in the gelcoat was .025 inch which equates to 625 micron or XL in new money.

Dave..... Have you ever mixed flakes yourself with gel coat and tried to spray it to a mould rather than use a brush? Wondering if it`s as simple as it would sound. (Have something in mind for the future).

When low pressure high volume spray equipment came along I was often told this was ideal for metalflake paint application but have never tried it. All my spray stuff is old school high pressure stuff.

No - I don`t do the "spraying" thing   

I've orded XL metal flakes on E-bay:
In a few weeks i hope to sray with it

Let me know how you get on and what gear you use

metalflake from the 70,s used to go by name,i.e metalflake/glowble/flip flop etc.as well as automotive supply for the particles try greetings card suppliers ,my brother used to work in the card industry and got prices quite a lot cheaper than many paint suppliers.though they might be a bit reluctant to supply small amounts.

try greetings card suppliers ,my brother used to work in the card industry and got prices quite a lot cheaper than many paint suppliers.though they might be a bit reluctant to supply small amounts.

The stuff used on Greetings cards is not UV stable and fades really quickly 

no it has to be uv safe as thats what they dry printing ink with

I got mine from here

http://www.ibbotsonflake.co.uk/index.html

Modern flake fades like mad anyway, red fades to pink in double quick time and when I built the chartreuse flake that had been East Coast Buggies demonstrator shell you could clearly see where I took stickers off the bonnet. Maybe Ambre Solair should introduce sunblock for buggies? 

If anyone knows of anyone that has old stocks of the traditional Meadowbrook foil (rather than the modern polyester) flakes in stock can they let me know? Asking for a friend, ta!

I'm going for the L size 0.15 but not sure how much to order to get full coverage (i.e. No basecoat visible) on a Lwb gp if anyone has any ideas. Having to order from US to get the right colour.

Paul,
all my setup is hvlp
flake gun i plumped for a Roth flake bomber 2.5mm tip. got stung by customs for it though (came from america) workked out at around £90 then another £30 customs and £16 for royal mail to release it to me 
as for the flakes Roth do some realy trippin stuff but i have to say house of kolor are fantastic