Fokker D8 wing streaking test update

[Dan_San_Abbott]

Winter Hawke;
After the wing is stained, wipe off excess with clean cloth in the same direction. Allow to dry. After the wing has dried apply two coats of matt varnish. Allow varnish to dry between coats. lightly sand the first coat, and ust throughly. Paint the matt black crosses. allow to dry and then paint the flat white borders. You will not have any bleeding.
Blue skies,
Dan-San

[WinterHawke]

Originally Posted by Dan_San_Abbott

WinterHawke:
The streaking is too light, the color have more intensity.
Blue skies,
Dan-San

This is how the wing is now - note that there is a color shift towards blue, as it is indoors under flourescent lamps:

Should it be more like the pure stain colors? This photo are from the previous thread by Langdon:

[Langdon]

It is wonderful to see so much interest in this once controversial camouflage scheme! Don't we all wish it was plain olive drab? It would be so much easier.

Just a thought, would it be a good idea to put all E.V - D.VIII discussions under one folder in the Aerodrome site rather than all over the place as it currently is? My suggestion would be Fok. E.V - D.VIII as a sub forum of the Aircraft forum.

1. Would the stain have been applied to the bare plywood only.

Yes. However, in our tests, we had trouble scaling down the effect to ¼ size. So a preliminary coating was added to help. While Del’s wing is ¼ scale, the grain of the wood is not!

Certainly it would have been applied only to bare plywood, as a stain it is not much good for mixing with substances other than alcohol or water. We applied ours (to the test pieces) with a 100 mm, course bristle brush, lightly charged to minimise the blotting problems. It is a problem in full scale, I would hate to overcome this in ¼ scale.

2. Was the plywood surface sanded.

Lightly sanded. The skins are very thin (1/64th on the model), and there’s not much room for too much sanding. At some of the edges, the much darker underlayer becomes visible when sanded. The sealer Del used was color matched to the color of the plywood, to help mask this.

Lightly sanded and not sealed.

3. How about the areas were there was glue out side the join that soaked into the ply layers.

The stain will not cover these areas and we are trying to minimise the amount of glue seepage but it was probably not a concern on the original.

4. Glue would inhibit the absorption of stain. Causing very light stained spots.

The color is noticeably different over the glue, as one would expect. On the model, CA glue was used – something unheard of 90 years ago. This was another reason for sealing the wing.

Again, the sealer only slowed down the absorption, it didn’t eliminate it – the goal was to miniaturize the effect.

Correct.

5. The stain would have soaked quite quickly into the wood only if the wood fibers were soft, darker coloring, as if wing was sanded or if the wood grain was raised.

If the stain was the least bit wet, or heavy, it wicked in very quickly, and it didn’t seem to care what it soaked into (you should have seen Del’s hands!)!

It is absorbed very readily anyway and needs to be applied quickly with a comparatively dry brush.

6. Plywood has a burnished finish from the mill and sometimes a waxy type coat from the fabrication of ply bonding, stain would have not soaked into the wood as much as laid on the top surface, lighter coloring.

The 1/64 ply does have a finished side, but it still is porous, and the stain was very happy to soak in given the chance.

7. Type of brush used equals how much stain it would have held and how long to pull.

We actually found the brush made a big impact! Softer brushes retained more liquid, and it was almost impossible to get the stain to streak. A stiffer brush worked much better – I believe that Dan-San mentioned in Langdon’s thread on the subject (referred to very frequently this last weekend!) that he felt that something like a wallpaper brush was used by Fokker.

We used a stiff brush, not a paint brush, with long, fast, light strokes. I think this scheme would have been applied in a very similar manner to the way the Dr.I was painted, although the stain would be harder to apply in the streaky effect than the pigment on the Dr.I.



Courtesy Dave Watts

The angle of the paint strokes on the scheme is the natural angle used by a righthanded painter, painting in the position shown in the photo above.



Fokker Heritage Trust

8. Brushed recharged more then once on same pull. Dark to light and dark to light on same pull.

Actually, the brush was infrequently recharged. Very little stain was needed to accomplish the streaking. More time was spent getting the load on the brush right – the technique ended up being a kind of dry brushing rather than painting with liquid.

As above, one charge will cover about half a metre of wing span.

9. How concentrated was the pigment in the stain mix, ratio of solids to carrier.

We ended up being happiest with the stain mixed per the instructions. One packet of the powdered stain was mixed with ½ Liter of liquid. Thinning later just made it harder to get the brush “dry” enough to streak the stain.

I will have to ask Koloman but he has noted the concentrate we have experimented with on the test pieces (below) I think pure is a ratio of 1:1 and the other samples relate to a watering down of this mix.





10. What was the carrier for the color pigment.

Del used denatured alcohol - Alcohol was what was listed on the packet. It was mixed, per the instructions, by first heating a pan of water to about medium-low, then a second pan of alcohol was set into the heated water. The heated alcohol was then mixed in the final container with the powdered stain.

We used water as a mixer as the Fokker title block made no mention alcohol, they didn't mention water either but we thought they would have this on hand, the title blocks are usually very accurate in the materials used and their quantities.

As a note, our references were the above mentioned Thread by Landgon on his research on this subject, in particular his photos of the streaking tests. We balanced those against Dan-San Abbott's drawings on the subject plane, and the Stec photo (post 101).

My views on this camouflage scheme are very similar to Dan-San's, the only difference I note is that I do not believe there are intentional, different styles, rather I feel that the differences come from the poor repeatability of the streaky camaflouge style, it all depends on how the brush charge is covering and also probably, on who is doing the brushing.

Dan San,

I have photos that seem show the varnish to be high gloss.

Langdon

[womenfly2]

Just awesome guy's! Great idea Langdon to put this information all in a sub-title. How do we do this? Can someone set this up?

On the streaking, great points Langdon made. I do not think Fokker or his employees we artists or had any great care in applying this stain other then what they were shown.

As with today's employees its an 8+ hour a day job only and not their life. With shortages of material at this point in the war limited materials and tight control on material allotment was a real concern.

I read somewhere that the DR1 wings were not at times completely varnished protected due to allotted amount of material give to the painter and how heavy he/she applied this. He could run out of material before the total wing had a even coating. ( This maybe incorrect, comments )

What we need to consider in all this is, think like a work/employee in Fokkers factory and how he would have applied this stain and not let our artistry get in the way .... is it lunch time yet?

I also think pictures in B&W of test wings would be useful for comparision to the RL photos for wing depth of color.

Just some thoughts ... comments:

All this testing and discussion is fantastic ... keep it coming!

[jumpinjan]

I'm a little confused here. My question is why did you use a solvent like alcohol to use as a medium to apply the dye to a model? Why not use thinned Nitrate dope as the medium to apply the dye? We use to do this on every free flight model that we built back in late 1960s &'70s, but we used RIT clothing dye instead. Another point is why are you using the same authentic dye powder that Fokker used 85 years ago? Here's an alternative dye that is widely used in "Candy" car finishes, so I would assume it should have more resistance to sun fading (since it's designed to be applied to a car)
http://www.houseofkolor.com/hok/products/specialty.jsp
I have used this "INTENSIFIER KANDY KONCENTRATE" a lot and I still have a few containers left and I think they have roughly the SAME colors available as what you are using. A word of caution, white paint (for the crosses) will not stop their tendency to "bleed". You need to apply a sealer (specially made for this) first before the markings, white & black crosses, are applied.
You know, if I can get some spare time, I'll try my intensifier dye and if I find anything interesting, I'll give you a full report.

[Langdon]

Originally Posted by jumpinjan

I'm a little confused here. My question is why did you use a solvent like alcohol to use as a medium to apply the dye to a model? Why not use thinned Nitrate dope as the medium to apply the dye?

Another point is why are you using the same authentic dye powder that Fokker used 85 years ago?

I suppose the point is to make it as it originally was. I'm not so up on model building but don't you only use dope on fabric? The wing is plywood covered and the camouflage is a wood stain, the instructions are specific on how to apply the stain.

Langdon

[Dan_San_Abbott]

JumpinJan;
Plywood surfaces were never doped, the were sealed with shellac and finished with varnish. In the case of flying boat hulls, the plywood was finished with enamel paint, i.e. Dehavilland 4, 9 and 9a forward fuselages.
Albatros used yellow ? shellac and clear varnish to finish the plywood fuselages.
Blue skies,
Dan-San

[WinterHawke]

Good evening, all . . .

Jumpinjan,

Dope was never a consideration for the stain medium - as mentioned, it is far more suitable on fabric than bare wood, and would have added it's own quirks to the equation. Del went with alcohol because that was what is specifically called out on the stain packets, and it's fairly benign. Also, the alcohol (or water) would dry leaving little behind, unlike the dope.

As Langdon so intuitively states, one of the goals here is to try to use the stains in the same way as original, as far as practical. We modelers unfortunately have some added variables that we have to deal with, such as scale effect of the materials and fuel proofing requirements, but I think Del's on the right track here.

It may be an option in the future to use more modern materials instead of the stains once we know what this looks like, but for now, we're trying to stay as true to the original as possible, taking our best guesses along the way.

Langdon,

Thank you so very much, first off, for that wonderful original thread that started all this madness (yes, you're quite right - why of why couldn't the wings have been olive for all our sanity's sake?!?) Your photos have been a tremendous help so far, and the new ones help explain some of the issues we're fighting now.

I was pleased to read that we had arrived at very similar techniques concerning the application of the stain - stiff brush, light fast strokes, rather dry - I don't think many people realize just how difficult these stains are to apply in a consistant manner if a streaked effect is desired! We tried, as much as possible, to match the style your original pictures show - our biggest concern was how intense to make the colors. The difference between the brown and the violet is extreme, and we struggled getting a balance between the two.

Del has gone back and added some more color to the bottom of the wing (along with the crosses), and will tackle the upper surface next. Follows is the latest photo of his work.

A question if I may - Have you any test samples showing results after the clear varnish application? Our present plans here are to use a clear semi-gloss outdoor polyurethane (the reasoning is for it's ease of handling, UV protection and fuel-proofing qualities), and in our test panel, we did see some change in the colors (but that was with the somewhat subdued colors we originally tried). And we did assume that the finish is glossier rather than matt, as several of the better photos seem to show a reflective finish.

This is going to be a very different looking machine - somehow I can't get the image of a beetle with shiny green and purple wings out of my mind! And it is definitely going to get people stirred up.

Fun, fun, fun!!!

Many thanks to all, and we'll keep the updates coming! Dan-San and Langdon, please keep us on the short and narrow, and we'll try to keep it true!

'til later,

Lee McDuffee
the WinterHawke

[Langdon]

Originally Posted by WinterHawke

Have you any test samples showing results after the clear varnish application?

This is going to be a very different looking machine - somehow I can't get the image of a beetle with shiny green and purple wings out of my mind! And it is definitely going to get people stirred up.

Many thanks to all, and we'll keep the updates coming! Dan-San and Langdon, please keep us on the short and narrow, and we'll try to keep it true!

Thanks for the very kind words Lee, as I mentioned above its wonderful to see so much enthusiasm for an aircraft that many seem to feel looks too modern and therefore not as interesting as the biplanes or triplanes (they're all wonderful).

The test samples in my posting above have been partially lacquered, I was hoping it would completely transform the colours but it didn't although they are a deeper shade. I have asked Koloman to try using alcohol as the mixer as I'm hoping that may stop some of that blotting effect by drying much faster. You are absolutely correct, applying this scheme is much harder that you might expect and the violet and green require some toning down to match in with the blue and brown, to me the green needs to be darker like lush grass.

Having said that, the outboard areas of the wing in the Fokker photo look to be very dark violet indeed in contrast to the lighter areas which must be the blue, the top side of the damaged wing on the right side of the photo does not appear to have the same tonal difference between the two upper surface colours.

If I can give a critique of your wing above it is that you have angled the brush strokes too much, in the Fokker factory photo above, the angle is about one rib bay for the wing chord, adjacent to the inboard side of the port aileron.

Do you have any photos of the fuselage that you could post?

Langdon

[womenfly2]

Wow! The wing in the streaky camo looks better then I pictured. Great work guy's!

When I built my Pietenpol AirCamper I wanted the varnished wood to look like the old varnish used in the 1930's. Talking with the crew at Rhinebeck and Owl's Head museum I came up with a product called "Epifanes". Its sold at boat supply stores and has a UV barrier in it. When applied it has a golden brown tint to it that very closely matches the varnish on some of the older planes at both museums. I was told by Ken Cassin at Rhinebeck it is pretty close to the varnish used in WW-1 and throughout the 1940's.

Just a thought for the top glossy (or matt?) varnish coat, they have both. Give it a look:http://www.epifanes.com/home.htm



Dan,

Could you post the wing drawing showing the outline/details of the camo finish?