Assembly: Aeroworks QB 150cc Yak 55M

[Naughty Monkey]

Joe, have you had any planes that you have used aileron differential?

 

[stangflyer]

I thought about extending the motorbox and not using an engine spacer. But, my flying buddy has a 4 cylinder that he thinks would be fun to try on this plane (after I get a few flights on the plane with the twin). So, I started in on an engine spacer. This is the longest one I've made... 2-3/4". Here is twelve pieces of 1/4" aircraft plywood rough cut. I actually only need eleven so one will get tossed. I still have to lightening hole them all and drill the four bolt holes in all of them. Then I'll epoxy them together, grind that hunk down with a drum sander, and finally seal it.

View attachment 39163

These 4-1/4" long bolts are not going to be long enough to get a locknut on the other side of the firewall. I'll need to order some 4-3/4" bolts.

View attachment 39164

 

[stangflyer]

You know Joe, if ya don't want to use that 3dub, just send it to me. I'm pretty sure I can find a use for it. Lol

 

[Joe Hunt]

Joe, have you had any planes that you have used aileron differential?

Pre protractor days I would use it on all my planes. Later I think the only plane I can remember using aileron differential was my CompARF with skinned hinges. How about you guys?

 

[Joe Hunt]

You know Joe, if ya don't want to use that 3dub, just send it to me. I'm pretty sure I can find a use for it. Lol

Might put it on this plane. Or, the Sukhoi... can't make up my mind. Walbro carburetor... interesting...

 

[Naughty Monkey]

Pre protractor days I would use it on all my planes. Later I think the only plane I can remember using aileron differential was my CompARF with skinned hinges. How about you guys?

I have only heard of using aileron differential to help with yaw while rolling. Now I am wondering if it might be part of poor geometry. If you did use differential, would you still keep the neutral point of the servo centered so you had equal degrees of throw and just move your horn location to get the differential you want?

 

[jamesrxx951]

Pre protractor days I would use it on all my planes. Later I think the only plane I can remember using aileron differential was my CompARF with skinned hinges. How about you guys?

I do not use differential. Rolls very axial.

 

[jamesrxx951]

I have only heard of using aileron differential to help with yaw while rolling. Now I am wondering if it might be part of poor geometry. If you did use differential, would you still keep the neutral point of the servo centered so you had equal degrees of throw and just move your horn location to get the differential you want?

When I had rolls that were not axial that was my problem. This was before I learned how to get my geometry correct. It took me a lot of time figuring it out and im sure I remember watching some of Joes older post from down on the deck.com to help me figure out what to do. Since I was newer in the hobby I didn't know what aileron differential was. But my mid travels were not equal from aileron to aileron.

 

[Joe Hunt]

I got back to working on the engine spacer. I used a 2" holesaw and drilled holes in all eleven plates. Then I epoxied them together, ran the engine bolts through (that I coated in teflon lube) and clamped the whole mess down tight:



While that was drying I glued in my rudder servos. I did the 12 step program and they came out perfect:



Previously I had put the control horns on the rudder. I wanted to put the DUBRO 10-32 control horns on the rudder like I did on the ailerons. But, again the hinge was in the way for that type of horn. And, I already know I am fine with the stock AW horns, so I just used those. Last one of these AW planes I assembled I did the stock pull/pull setup per the manual and the geometry came out perfect. So, I'm hoping that's the case here too.



I put the stock AW controls on with black servo screws, just cuz I thought they were cool. haha I did put thin CA down each of the holes to soak into the balsa before I put the screws in. The screws had a real solid bite.



Finally I got back to the engine spacer. I started sanding on it for a few minutes with a spindle sander and then called it a night. It took an entire 12"x24" x 1/4" piece of aircraft ply to make this spacer. That sheet weighed a ton. After I got the eleven plates and drilled out the 2" center hole, and glued it all together, it weighed 11oz. I'll get it down to 8oz or less with the spindle sander. Still half a pound, but it sticks out 2-3/4"... so it's just big.

 

[Joe Hunt]

I called it at 8oz. I could probably make it 2 oz lighter, but it's so tall. For all the time I have into it Monkey would definitely get upset if it were to crack because I made it thinner. I can live with 2 extra oz.