Waco SRE by Earl Stahl

[marcin_pl]

Time for covering. I used Esaki tissue for the first time. It's different than a material being selled in Poland under a name "japanese tissue". "Our" japanese tissue is more porous, with distinctive fibers. It has no wet strenght and is shrinked by a shrinking dope.
Esaki was a new experience to me so before putting it on the model I made some test frames. I was afraid of a shrinking force, which could deform delicate structures. After the tests I decided to use Esaki on stronger parts: fuselage and wings and a thinner Kashmir tissue on the stabilizers. Esaki was shrinked with water from atomizer (I was a bit afraid of it but it went OK). All parts got two layers of mixture of 50:50 shrinking and non-shrinking dope.
So far so good and now all the elements except the fuselage are attached to a building board for at least a week.

Marcin

[marcin_pl]

I prefer to trim my models by setting a horizontal stab angle. Typically I use small slivers of ply, balsa or cardboard and put them under leading or trailing edge of the stab respectively. But after reading MKelly build log about his Waco I decided to use his idea of a "regulator" with a small plastic screw. It turned out easier than expected and works brilliant! Additional weight can be neglected but a stab angle can be set with stellar accuracy.

Marcin

[kaintuck]

Very nice! Your building skills are terrific.......should be a nice plane, please keep us informed.
Marc

[Crabby]

Hi Marcin, I have that plane on my bucket list just for pleasures' sake. I have my Dad's which he flew indoors, it is the Mooney peanut scale SRE. I will check out the decalage today, I can attest to its solid flying.

[Konrad]

I prefer to trim my models by setting a horizontal stab angle. Typically I use small slivers of ply, balsa or cardboard and put them under leading or trailing edge of the stab respectively. But after reading MKelly build log about his Waco I decided to use his idea of a "regulator" with a small plastic screw. It turned out easier than expected and works brilliant! Additional weight can be neglected but a stab angle can be set with stellar accuracy.

Marcin

For RC gummy band conversion I like to set my decalage at 0.5° (up trim using the wing chord line as the datum). This often ends up being parallel with the bottom of the wing if it has any Philips entry in the airfoil.

Note; I do like a rather aft CG.

[marcin_pl]

No, this thread is not dead 

I started the wheel pants. I must admit I love them and I hate them.
After some thinking about attaching them to the undercarriage legs I made a simple jig. It helped me to keep the same atittude of both wheel pant equal.

Marcin

[Konrad]

What's to hate? THEY LOOK GREAT!

[ZK-AUD]

Agree it looks great.   The bit I hate is having to glue them back every time they get knocked off or around. Then I had an epiphany while building my Corby Starlet and bent the U/C wire a different way to provide a really strong mount for the spat.   The wheel axle is a separate piece. Photos to explain at reply #19

https://www.hippocketaeronautics.com/hpa_forum/index.php?topic=25412.0

[marcin_pl]

ZK_AUD,

Interesting concept - I have to try it in future.

A used a bit different approach. The main undercarriage leg is also an axle for a wheel. A small piece of plywood with oval opening is glued with epoxy to the undercarriage legs. The oval opening and epoxy on two legs block rotation around the axle. A spat has small plywood "bearings" glued inside, that support an axle. The small plywood inset is recessed into a sidewall of a spat.
Assembly is very easy and allows for final tuning of a spat attitude.

Marcin