Replies

1. 
   RickL | May 11, 2009 03:30pm | #1

   Two things I would do

   1 Call the manufacturer of the Lacquer...problem is you can't be sure of the info unless they can send you teat data. I'm always coming up with stuff they haven't tried yet but sometimes it's something they actually did. Also some techs are more knowledgable than others.

   2 Do a test

   Can you really rely on an anonymous post?? Don't care if they say they've been doing it for 150 years. It's your reputation on the line if it's a client involved. Forums are interesting but the old tried and true methods before the web have a lot of merit still.  Everyone wants instant answers but if you don't have a reliable source it's worthless. 

   
   

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   Edited 5/11/2009 8:58 am ET by RickL

2. 
   roc | May 12, 2009 05:06am | #2

   A good source of info is automotive painting books. A couple of thoughts. If the aluminum is anodized from the manufacturer then the lacquer won't stick well. Sanding it will definitely remove the anodizing. Problem from there is you need to coat it immediately ( in a few hours ) with the lacquer or the unanodized raw aluminum will begin to form an oxidized film and the aluminum will turn a bit dull, not bad, and the lacquer may again bead up and not flow out or stick that great.

   There are etching or surface prep chemicals you can get to "passivate", for lack of better term, the raw aluminum and allow a bit more time to spray it and to keep it from not excepting the clear coat.

   I come at this from a purely metal working angle. Not sure how these chemicals will effect the wood. Also you are going to get some metal in the pores of the wood if you sand it and then you could have some "glitter" here and there in the wood that you don't want. Tricky.

   May be best to sand metal and wood separately. Sand or treat the metal at the last possible moment before clear coating. Probably want to go way finer grit on the metal than the wood depending of the finish you want.

   If the alu is anodized and you are going to coat over it without sanding then there are wiping chemicals which is like lacquer thinner without so many additives just to get the surface super clean ( that is get all the finger prints and skin oils, silicone contaminates and to break down the surface tension as much as possible ).

   Clear coat can scratch off this anodized surface easier than the de-anodized surface but at least it will flow out right.

   roc

   Give me six hours to chop down a tree and I will spend the first four sharpening the axe. Abraham Lincoln ( 54° shaves )

3. 
   chairmannz | May 13, 2009 04:37am | #3

   I have made furniture with aluminium in it.
   Routered the holes in the panels, spindle moulded the outside shape, use tungsten tools and if possible buy them for aluminium.
   I sanded it with 120 grit paper and started spraying a bout 3 days later, had to sand about 20 panels and the weekend in between.
   I went to car paint shop and asked what the best option is for under coat and what soort of lacquer i spray on top.
   They gave me a good clear car lacquer for a base coat.
   Then when the furniture was assembled i used clear furniture lacquer over it.
   No problems till now and still looks like after sanding it.
   Let us know how it turned out.
   Cheerio Bernhard.