Model Boat Mayhem

Technical, Techniques, Hints, and Tips => Painting, Finishing and Care. => Topic started by: Pointy on June 04, 2006, 04:25:44 pm

Title: Varnish- is it necessary
Post by: Pointy on June 04, 2006, 04:25:44 pm

The instructions with the boat I'm building recommed using Halford Acrylic Car sprays. This stuff is used on cars- cars which stand outside in the rain,the sun go through car washes etc  why do I need to spray a layer of varnish over it? I've tried to in the past and it ruined the model I built because all the white of the superstructure went urine yellow. I asked some guys I met today who were running scale destroyers on the lake where I was. They said they used enamel and never sprayed varnish over the paint work and yes they couldn't stop white going yellow either.

Could someone help me with this? Do I use enamel all over now because it is harder (I'll need loads!) or will the water based Acrylic be okay without varnish? Does anyone know how to stop white going yellow with varnish? :-\

Title: Re: Varnish- is it necessary
Post by: Stavros on June 04, 2006, 06:45:39 pm

Wiht most car sprays they are what is called a base coat which has not got any laquer jn the paint so to get any gloss you need to give it a coat of laquer to get a shine,as for white going yellow with varnish the trick is very simple.Instaed of painting the article with white gloss then applying varnish,apply a car based white base coat then spray with a laquer coat and hey presto no more yellowed white ;)

Title: Re: Varnish- is it necessary
Post by: barriew on June 09, 2006, 06:46:30 pm

Been meaning to reply to this for a while and keep forgetting..........

I varnish for two reasons (scale models)

1. I tend to use different paints - enamel gloss, matt, satin and acrylics. A coat of varnish make the finish more uniform. It also affords some protection to decals and vynil lettering
2. To give some protection.

As for yellowing, Humbrol Matt, Satin or Gloss Cotes don't seem to affect white in the same way that polyurethane varnishes do.

Barrie

Title: Re: Varnish- is it necessary
Post by: Pointy on June 10, 2006, 10:30:15 pm

Thanks for the replies guys, do you thin the Humbrol Clear cote before you apply it?

Title: Re: Varnish- is it necessary
Post by: barriew on June 11, 2006, 02:03:09 pm

Yes - the matt quite a lot, the satin not as much - dont ask what is a lot 'cos I didn't measure it.  ;D

I did the matt when it was quite cold and it was very thick and difficult to mix. The Satin seemed thinner. I brushed both finishes.

Barrie