I was reading a woodworking magazine and it had an article on coatings. One section was on varnishes and it explained what the types were. I started googling varnish, mostly for WW1 wood frame models for my use. Probably what was on the planes was a derivative of what they call "boat soup". It would be cheap to recreate but probably not a good thing for models. Violin varnish looked like the perfect thing, but the real stuff is expensive, like $200+ an oz! Then I came upon this and it looks promising; looks like it can be mixed with just about any carrier. http://www.stewmac.com/shopby/product/5032

I just sent that off to a friend trying to figure out staining Koverall. Thanks.

Martin

Martin, is your friend hoping to stain the Koverall BEFORE applying it? I can't imagine that working. The problem I always have with stains is that I have to buy dozens before I find one that has anything like the color I really want. [:'(] For example the can of "Golden Pecan" Varathane stain&polyurethane (water-based) that I just tested is PINK! There's just no other word for it.

It might be able to die Koverall, but that is not how I see it used. You can tint your dope, poly, your clear whatever, and bring up the color by layers. From base coats up. In the PC10 debate, the brown shift has to come from the varnish darkening in the Sun. Ever see the antique furniture that is all black? Old boat soup type of varnish darkening over the years. Musical instrument builders are pretty picky so I think primary staining of wood either by directions or slipping some in dope might get the right look, and I am thinking on the PC10, a lightly tinted coat might be the thing.

I did a LOT of testing with stains and other colors (coffee) added to polyU and Nelson's clear and never got something I wanted to use (as clear doped linen). The probably with the "layers" approach is that you have to work out how many layers the model really needs first, and then you need to add just enough color so that the total number of layers together create the right color. Another problem is that it tends to "pool" or go on heavier in some areas and so then you get an uneven color...and not in a good way. I'm not saving it can't be done but it would talk an awful lot of testing.

My own opinion on this, based on photographing my SE5a model in different light on the same day, is that the "brown/green" issue is a matter of reflective properties in different light. In direct sunlight the model appeared brown, but in open shadow (which tends to have a bluish quality) the model appears more of a darkish green. What a coat of tinted varnish/clear/Poly might add, however, is a pleasing depth to the finish.

The original poster is talking about staining wood if I read him correctly.

Use water based stains for your fuse wood parts. This wont effect the glue adhesion later on.

There are a number of dyes that I have that are used for wood. These come on power form to be mixed with water. I bought them at Wood crafters.

Keep in mind that the wood you are using is different from the woood used on the full scale. You'll have to take that into acount. Unlike my guitars you dont want the wood grain showing as an attractive feature.

Proctor Enterprise also sells water based wood stains that work out just fine. So thats another sourse for them.

OD has pretty much the same color properties as PC10. In as much as it too changes the color shift from green to brown depending on sun or shade.

On the topic of staining wood, I haven't had much luck there either. The stains always seem too "thin." Partly this is because we are often using very light colored woods, like basswood. I got a nice color for the fuselage of my CI (over birch ply) but it took weeks of testing and 5-6 brushed on coats. I think I tested at least half a dozen different water-based and oil based stains and lacquers. In the end, I ended up using a water-based Japanese stain labeled as "teak." Curiously, the oil based "teak" from the same company looked completely different.

The original planes were done in spar varnish which is in the family of long oil varnishes. That is where I started my search. I was even thinking of mixing up some boat soup or boiling some violin varnish.

If you don't mind me asking, whats the point of all this effort? You dont have the original type of wood so regardless any stain will need to be 'adjusted' to look right.

Oil based stains really don't work well in our application for a host of reasons.

I understand that but I had to learn a little history on the subject and what was what. They still put the varnish on, much improved for sure but much the same, but it is now used as UV protection for epoxy. I also thought it would be cool if the plane survives time, that it ages like a museum piece.

FYI you can alter the colors of stain by adding universal tint to them to tweak a color to suit your needs, when I worked in a paint store we did it all the time to match colors in WB and oil based stain sometimes combining stock colors to get in the ballpark then pushing the color closer to the desired results with tints.

if you have a good quality store they can match small quantities as small as 1/2 pint