Model Boat Mayhem

Technical, Techniques, Hints, and Tips => Painting, Finishing and Care. => Topic started by: Colin Bishop on October 01, 2015, 04:20:13 pm

Title: Polyurethane Varnish
Post by: Colin Bishop on October 01, 2015, 04:20:13 pm
As some people on here will be aware, I am a great fan of traditional polyurethane varnish which can be used over most finishes without problems and is very durable. Several firms make it but it is less easy to obtain than it used to be as the main outlets often only stock the acrylic quick dry type.

Earlier today whilst in a traditional hardware shop in Emsworth, Hants, I came across these handy sized 125ml tins from Blackfriar. They also do a gloss as well. They are not cheap on the face of it at £4.25 each (although a lot cheaper pro rata than Humbrol tinlets) but I thought they were worth it!

Colin
Title: Re: Polyurethane Varnish
Post by: BarryM on October 02, 2015, 11:34:11 am
Colin,
My experience of polyurethane varnish is that it acquires a yellow tinge over time. Have you managed to avoid this?
Regards,
Barry M
Title: Re: Polyurethane Varnish
Post by: Colin Bishop on October 02, 2015, 12:22:14 pm
Barry, any varnish will tint the underlying finish to some extent so it is best not to apply it over white or very light colours. The interior polyurethane does not have UV filters and is clearer but if your boat spends most of its time indoors out of bright sunlight there shouldn't be a problem. The exterior type has filters which protect it but it has a yellow tint to start with which of course isn't usually a problem with wood finishes!

Paul Freshney who has a reputation for his excellent model boat paint finishes uses Ronseal polyurethane well thinned down and sprayed on and has never had any problems that I am aware of but he does look after his boats which are usually kept in boxes - as are mine.

The UV in sunlight & daylight will break down almost anything given time!

Colin