Offer four data points that may serve just to confuse but here goes.
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</div><div>A. In 2003 timeframe covered a BALSA USA N28 with full F&M process from Polyester covering applied with Polytac, 2 coats Polybrush and a couple of coats of PolySpray followed by Polytone paint just like the Video from Chip Mull. No problems with sagging or wrinkles but the paint is not very resistant to hanger rash. Use Glow engine and no problems with fuel residue. It has a semi-gloss finish and over the long term sort of dulls. Otherwise is fine.</div><div>
</div><div>B. Next plane, 2005, was a 1/4 scale Albatros where I used the same F&M process up thru and including Polyspray but painted with Klasskote paint. Lightly scuffed the Polyspray before the satin KK and it has held up great. Looks like the day it was painted and the surface is tough. No cracking or wrinkles. Only comment would be that the light red and light green does not cover real well. THe Blue and Dark greens and especially white cover well. The challenge with KK is not to build up a thick layer.</div><div>
</div><div>C. Next plane, was a 30% BU-133. Covered in Koverall using Nitrate dope for attachment and filling the weave. painted KK directly over the Nitrate dope. Applied about 8 coats of 50/50 Nitrate dope and used the F&M pinking tapes with lots of coats of dope to fill them. Had pin holes where the dope did not 100% seal the weave over some solid areas and in some areas of the pinking tapes that did not get enough dope I believe. I also suspect that the Koverall might have a more open weave than the F&M material. THe plane was painted gloss yellow and I should have first applied a coat of white for a uniform surface. Otherwise the paint has held up great with no issues in hot weather. THe Nitrate dope keeps things tight. Also like the use of Nitrate dope that completely fills the material, just like Polybrush fills the Polyester covering from F&M so that you can make any edge overlaps disappear with some care and fine sandpaper. Looks just like the day it was painted, about 3 years ago.</div><div>
</div><div>In comparison the Polybrush perhaps fills the weave better of the Polyester material than Nitrate dope does with Koverall but both work. </div><div>
</div><div>D. Next was a Taurus pattern plane that covered with natural Solartex with Niitrate dope over it (as recommended by others, it as an experiment and painted with KK without any primer. Applied two coats of Nitrate to the bare balsa before applying the Solartex based on recommendations from others. Painted it dark blue and white and had no issues at all. I found that I should have been more patient with edge overlap of the Solartex as, I suspect due to the Solartex adhesive, was hard to make them disappear.</div><div>
</div><div>For a small area like an elevator or rudder Soartex works great and would continue using KK paints. For the lighter colors would first apply a light coat of white.</div><div>
</div><div>Have a balsa USA kit for a SPAD XIII and I suspect the best of both worlds might be to first cover with the F&M process, might use something other than POLYTAC to apply it like STIX-IT, up thru application of the Polyspray and than paint with Klasskote using the satin catalyst which seems to spray easier than the Gloss catalyst. THe Gloss catalyst seems to run easier than the satin catalyst. If a gloss is required than use a KK or other gloss clear coat. (Per Dave Platt video). I am tempted to use Latex but have not yet. </div><div>
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</div><div>I have not used MINWAX Polycrylic to fill the weave of Koverall. </div><div>
</div><div>For what it's worth.....(which may not be much.....)
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</div><div>ray</div><div>
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