Lil' Satan build.

The MA GF series 6x3 cut down is my favorite prop. They are a lot harder to break than the Cox grays, and they balance pretty easy. Much much easier than the black Coxes. I don't know if the holes are the same size on the 7x3s. I still ream the front screw hole in case it's off center, and use a spacer in the rear. To cut them I use my engineering compass set to size, plug one point in the hole and scribe where to cut. Then cut it off with scissors or fingernail clippers. Sand the tips round and sand the back side to balance. I cut them to 5", 5.25", and 5.5". If the hubs won't balance easily, I just save them for slower engines.

I buy them from Windsor Propeller Company, $1.69 for a pair.
http://masterairscrew.com/gfseriespropellers.aspx

Well, added washers for down thrust and it flies straight and level no problem. Black widow with 5x3 is plenty fast, controls are snappy, but loops are big. Actually belly slapped it on the grass twice looping it. What should the control throws be on this plane? It seems like it might be coming into the circle when it loops, what would cause that? I'm pretty rusty and this plane is pretty fast so I may fly it with the prop backwards and try and analize the loop a little more.

Try a 5.5"x3" prop, that'll tighten up the loops. It's what I usually use on mine. Mine flew wider loops with a 5" prop, but i haven't tried it again since I braced the control rod. A 6" prop is too much for it. The throws should probably be around 25deg. Too much and it'll get worse too. I'll try to measure mine and see. I'll post back with that tomorrow. I made a 5.25" prop that I plan to try Saturday morning.

Coming into the circle, do you have outboard thrust? That's important on the Satan. No wing warp and the stab is parallel with the wing when you hold it up and eyeball it from the front? What about outboard wingtip weight? If you are using a streamer make sure it's tied to the outboard tail boom. I think mine does better loops with the drag from the crepe paper streamer on it. I still step back a bit when I do a loop.

Everything looks straight and plenty of side thrust as well as wingtip weight. I'll try the 5.5 prop. Like I said things were happening pretty fast so it was hard to analyze if it was coming in or not.

According to my crude measuring method, I have 20 deg. of up and 22 or so deg. of down. To get that throw, I have the elevator horn set to the sensitive hole and I filed off the stop nubs above and below the elevator on the tail boom.

Not being happy with the results of my scratch building efforts I purchased two lil' Satan reproduction kits on eBay.
http://myworld.ebay.com/henry36912&ssPageName=STRK:MEFSX:SELLERID&_trksid=p3984.m1543.l2533
I recommend this guy, good kits, not great but a radial mount kit AND a beam mount kit for $42 shipped. A few pics of the build.

Notice relocation of the tank to dead on the cg.
https://i.imgur.com/qU73y.jpg

Parts, nacelle awaiting paint.
https://i.imgur.com/BqUlj.jpg

The mock up.
Should fly sometime this week.
https://i.imgur.com/i41HU.jpg

Looks good, I am going to build one of these sometime. Hope this one works better for you.

Ron

After learning to launch from my new stooge(took about four attempts much to the amusement of the junior high kids who were skipping school in the park) I got some good flights in. Even tried inverted and got a solid lap in then a solid dive straight in!
https://i.imgur.com/9FJMj.jpg
The second attempt at inverted:
https://i.imgur.com/I3ckB.jpg
At least the Satan is easily repairable.
https://i.imgur.com/EPnIb.jpg
Maybe it was bad luck to make the plane match the epoxy bottles?!?

I think I'll try to find this plan...

Rémy

JPvelo wrote:After learning to launch from my new stooge(took about four attempts much to the amusement of the junior high kids who were skipping school in the park) I got some good flights in. Even tried inverted and got a solid lap in then a solid dive straight in!
https://i.imgur.com/9FJMj.jpg
The second attempt at inverted:
https://i.imgur.com/I3ckB.jpg
At least the Satan is easily repairable.
https://i.imgur.com/EPnIb.jpg
Maybe it was bad luck to make the plane match the epoxy bottles?!?

Woops! Good looking plane even with the booms snapped off. At least you got to go inverted mine went straight into the ground!

Are those booms made out of ply?

"Are those booms made out of ply?"

Yes, for now. By this time tommorow they will be ply and just a wee bit 'o the fieberglass.

JPvelo wrote:"Are those booms made out of ply?"

Yes, for now. By this time tommorow they will be ply and just a wee bit 'o the fieberglass.

Oh ok, must have been a good solid hit then to snap those things off.

It's beautiful. I love the clear red covering. Sorry to hear about the crash, they just refuse to stay pretty. How about the fuel draw with the tank like that, does it get a steady feed? Remember to re-balance it if you put ply and fiberglass on it. I see yours has a spar in the wing that mine doesn't have. I added one near the front that wasn't in the plans, just to hold the foil shape a little better.

Keep at it and keep us posted.

The extra spar was part of the kit and really helped the wing go together easy. I forgot to add tip weight so fuel draw suffered on loops when the plane got light and slow so the fuel sloshed inboard. Already added 1/4 ounce to the outboard tip and am going to pressure vent the tank with fuel tubing:
https://i.imgur.com/cWz3t.jpg
Also just picked up 40 engines on eBay and might play around with drilling one for crankcase pressure.

Rebuilt/shortened tail booms, extended nose 1/4 inch to move cg forward. More inverted practice today, straight into the ground full power. Twice. Sum total of damage: two busted props. I love this plane.
https://i.imgur.com/Nq3G7.jpg

What do you think is causing it to crash when you fly inverted? When it's right side up, does it fly level when the elevator is neutral? If you're new to inverted flying, I think it's best to use wrist only. Less muscle memory to train. The Satan may be harder for learning to fly inverted because you don't have a rudder on the bottom to tell your brain that it's upside down.

RknRusty wrote:What do you think is causing it to crash when you fly inverted? When it's right side up, does it fly level when the elevator is neutral? If you're new to inverted flying, I think it's best to use wrist only. Less muscle memory to train. The Satan may be harder for learning to fly inverted because you don't have a rudder on the bottom to tell your brain that it's upside down.

I can see that, but flying in the opposite direction might be your best indicator

"What do you think is causing it to crash?"
Inexperience, pilot error, and disorientation. Not necessarily in that order. And the sun was in my eyes. Also, the dog ate my homework.

Rather than jumping straight into inverted laps, try this: using only your wrist, start doing figure 8s. Do as many as you can without losing line tension(3 or 4), then pull out right side up and go around. When you're back up to full speed do 8s again but larger(not bigger loops, just stretched out for a longer distance). Keep doing sets of 8s, each time making them larger until they cover half a circle. Those are called lazy 8s. practice that and you will develop the reflexes to control it in either direction. When you feel ready, level off out of your 8s upside down and go around once and flip back over. Keep doing inverted but only one lap only at a time and then flipping back over to normal flight. You'll soon be comfortable with the reflexes and it will come naturally. Remember to have the wind at your back when doing 8s or flipping over to invert. Also use the least sensitive hole in the control horn.

Like the eights idea, will approach it from that angle next time. Thanks for the advice Rusty.

Tried the lazy eights, great idea Rusty. Thank you. Still busted five props but things are getting much better. Fun and somewhat relaxing to stand without spinning and watch the plane do consecutive eights.
Also wanted to report on the pressure vent setup I showed in an earlier post:
https://i.imgur.com/cWz3t.jpg
Works amazing, consistent fuel draw and steady rpm for entire flight.

Good, JP, I thought about that yesterday, wondering if you'd had a chance to try it. What's happening when you bust the props, are you pulling the elevator the wrong way when you're inverted? If you use Cox Black props, they usually won't break, you just unbend them and send it off to fly again. They are hard to balance if you try to balance the hub, but just balancing the blade is fine for sub-20k rpm engines. What about your arm action, are you trying wrist only? And one more tip; I think it's best not to try and rotate the wrist or arm upside down and right-side up as you follow the plane. I just thought all that might be less confusing, but only you can know for sure. Sorry if I'm telling you too much and just muddying up the water.
Can you point a camera at your field and let us see what you're doing? I understand if you don't want to post videos of wrecks.

I'm glad to hear the pressure feed into the prop-wash helps. I've never done it, but I have wondered if maybe it could work even better if you made a wide inlet for it, like maybe affix a forward pointing stub of metal tube to it.

Pilot confusion sets in when I stray from lazy eights and go for laps. I'm using master airscrew 7x3 cut down to 5 that I pick up at the local hobby shop for 1.75. The engine is a #1 cylinder on a horseshoe backplate that gives good line pull on 32". I may try 42" lines to open a little space between the plane and the ground. I was flying mostly wrist but I started to naturally straight arm it during the lazy eights. Interesting.