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Prep for the Wildcat Rangers' next expedition

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Prep for the Wildcat Rangers' next expedition

Post  RknRusty on Sun Aug 21, 2016 3:11 am

It's all set for our next excursion. I don't know if it'll be today or during the week. The wind is supposed to be 14-18 today but a lot cooler, in the low 90s. I've never flown the Twister in anything over 10mph, so I better feel it out, especially since I did some more bench trimming since the last flight. Every flight so far has been with more flap deflection than the elevator, and now I have them reduced to slightly less than the elevator, and I also got rid of that clevis.

Also, I've been flying tail heavy, and actually happy with it, but it'll probably smooth out with the CG more forward, but still aft of the plans. It was a 16th" in front of the spar, and with a weighted acorn nut on the prop, it's about 1/4" in front of the spar. I'd noticed it climbing when the power cut, and that's a telltale sign to adjust it. So I'll be flying with two changes, but nothing radical.  I really expect to fly better shapes right away except for obvious caution in the wind if we go today. Hopefully, better patterns than I was doing with the Cardinal, which is getting pretty rickety., but it and the Nobler will make two good backup planes

Before the tank leak, I'd been flying 5 second laps with 12 laps after the clover, and I hope I'm back to that. I'm going to miss the LA.46 with its one-two flip starts. With my disconnected bicep tendon, cranking is difficult unless I back-whack it. A dangerous habit, I know, but it's the only way I can do it. And the FP.35 has been taking me 10 0r 12 tries even though it bumps consistently after priming, and I get worn out and have to let Wayne crank it. The electric starter doesn't fit the acorn nut, so I'm not sure what I'll do for the contest. I could use a spinner and switch to a heavier muffler for balancing. If I like the acorn nut, I won't like messing with success, but I have 6 weeks to figure it out.

I know my videos last week showed mixed improvements along with some of the same old errors, but I have more confidence in this plane and myself than I've had in the past two seasons, including this past spring, when I took 3rd at H'ville and first at Triple Tree. I'll need to give Mike a bad day Lol. But beating Wayne is a bigger stretch. He was scoring low 500s at Brodak, and I have yet to score over 455. But personal goals are what I care most about, rather than what place I finish. So stay tuned, and we'll see if I can make the leap I want for the fall season.
Rusty!

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Re: Prep for the Wildcat Rangers' next expedition

Post  Ken Cook on Sun Aug 21, 2016 5:53 am

The LA, FP , Brodak, Max .35 share the same bolt pattern and case length. Put the FP .40 on it and it will add nose weight. Adding a aluminum spinner will do the same not to mention benefit from a starter. One real problem though with aluminum spinner backplates and aluminum engine drive washers is slippage. You can never get the two tight enough. Eventually it slips so making small sandpaper discs glued back to back grit out  between the two stops that. Back flipping is the best way to start any engine. I do understand for obvious reasons how you can get worn out quickly. You can't get hit by the prop in starting a engine this way. For those that aren't familiar with it, it should be learned.  The FP .40 is going to use more fuel so if that's not an option for your tank it's something to consider. A Brodak .40 would work beautifully but the plane would need almost 2 ounces of nose weight. If the plane is nosing up when the power quits, that could certainly have a negative impact on your landings due to your constant inputs to level it out and land. I certainly would look into that. If you get caught on the wrong side of the circle, the nose could pitch up and stall rendering a abrupt crash which I've seen do some real damage. This is where the fly swatter effect comes into play. The tail of the Twister is large and it can break off. The LA .46 is a good choice, in my opinion though it's a lot of engine for the plane. I have flown many Twister's using a good old Fox .35. Unfortunately, that's what I had at the time. Very underpowered when the winds kicked up. If the winds headed into the 10 mph range it got real loose up top getting blown out of the maneuvers.
 

    Looking at the plans on Walter's site, I see the gear arrangement and I have to say while that straight down gear leg is good for asphalt, it's horrible for grass. Generally, gear in this configuration will promote a flip over on grass landings.  It also has the wheels closer to the CG but I certainly would experiment with sweeping the legs forward as this could also pitch the nose down without adding additional weight. Of course all this is easy to say over the internet as I have no idea about additional obstructions on the plane and or ground clearance.  Does the plane bounce intially on landing?
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Re: Prep for the Wildcat Rangers' next expedition

Post  RknRusty on Sun Aug 21, 2016 10:35 am

Good morning Ken, thanks for the reply, good stuff. I hope you and Shawn can escape for a flight or two between slaving all day every day.


Ken Cook wrote:The LA, FP , Brodak, Max .35 share the same bolt pattern and case length. Put the FP .40 on it and it will add nose weight. Adding a aluminum spinner will do the same not to mention benefit from a starter. One real problem though with aluminum spinner backplates and aluminum engine drive washers is slippage. You can never get the two tight enough. Eventually it slips so making small sandpaper discs glued back to back grit out  between the two stops that. Back flipping is the best way to start any engine. I do understand for obvious reasons how you can get worn out quickly. You can't get hit by the prop in starting a engine this way. For those that aren't familiar with it, it should be learned.  The FP .40 is going to use more fuel so if that's not an option for your tank it's something to consider. A Brodak .40 would work beautifully but the plane would need almost 2 ounces of nose weight.
With my 3.5 ounce tank, I'd have to be careful with a larger displacement engine. I have two reworked fp.40s. I know the one Bob did got much better mileage, down from the 4.5 ounces it used in its stock config. I never metered it to find out exactly while it was flying my 55 oz. Oriental, unfortunately wrecked by my own mistake and following laziness. The fp.40 John Tate gave me is said to be efficient, so both of them rate a try if I so decide. That .35 gives me the stunt run of dreams, so I hate to mess with perfection. After adding the nose weight, I'm now over the 41 oz. mark, which isn't bad. My version of back flipping is to rotate it 180 off of compression and clobber it with my chicken stick(and only with certain strong props like APC). I can almost crank it normally with my bare hand and 3 fingers, but frequently get my knuckles busted.

Slippage is the reason I've quit using spinners, especially in contests. I didn't realize the aluminum ones(Tru Turn?) were that heavy. I think my acorn nut weighs 3/4 oz., and is as yet untested. I knurled the facing and screwed it against the OS prop washer, also knurled on both sides. A heavy Fox prop washer might also be a source of extra weight. Maybe I could partially fill the cup on my Sullivan starter with silicon to grip the acorn nut.

If the plane is nosing up when the power quits, that could certainly have a negative impact on your landings due to your constant inputs to level it out and land. I certainly would look into that. If you get caught on the wrong side of the circle, the nose could pitch up and stall rendering a abrupt crash which I've seen do some real damage. This is where the fly swatter effect comes into play. The tail of the Twister is large and it can break off. The LA .46 is a good choice, in my opinion though it's a lot of engine for the plane.


  Looking at the plans on Walter's site, I see the gear arrangement and I have to say while that straight down gear leg is good for asphalt, it's horrible for grass. Generally, gear in this configuration will promote a flip over on grass landings.  It also has the wheels closer to the CG but I certainly would experiment with sweeping the legs forward as this could also pitch the nose down without adding additional weight. Of course all this is easy to say over the internet as I have no idea about additional obstructions on the plane and or ground clearance.  Does the plane bounce intially on landing?
Logic be damned, in all 15 flights my landings have all been soft, any bounces have been minor and some have actually been greasers. Pretty amazing considering the horrible landings I'm famous for, so I'm reluctant to do anything to the LG that might change that. Of course when I try it with the CG a little more forward, all of the above glory could change.

And yes, the stab on this plane is considerably bigger than the Sig Twister. The fuse, being laminated with carbon veil in the center and wrapped in fiberglass and silkspan, maybe it's a little tougher than bare balsa. This kit actually came with a two piece fuselage meant to be laminated.

I have flown many Twister's using a good old Fox .35. Unfortunately, that's what I had at the time. Very underpowered when the winds kicked up. If the winds headed into the 10 mph range it got real loose up top getting blown out of the maneuvers.
This is the very first thing that impressed me on this plane, its authority in overheads. I'm used to having to be more careful heading toward 90 degrees overhead, but this thing just plows through with ease. I've quit flying behind my head in the V8 and HG and haven't run out of room yet. On my first video of last Sundays flights, I blew my V8 only because I topped out at less than 90, resulting in an awful shape on the bottom loop. That's the one I reflew on the next lap. Funny, when I first learned the V8, I flew it beautifully, and now I have trouble stacking the loops symmetrically. But I'm not going to consider a Fox. I know Bob would be thrilled if I did, he loves them, and defies all accepted Fox protocols while flying them.

Have a good Sunday. That goes for all of my readers too. If I get to go fly, I'll report back tonight.
Rusty

Edit in a question here:
I must've borrowed the steel thrust washer from behind the drive plate because it's missing. Since I'm not using a starter I couldn't think of a reason I need one, so I've been flying without it. Is it necessary? If I decide to use the electric starter, I'll put one on it. I guess if the engine burps, or when it's shutting off, it might be better to have that washer in case the crankshaft floats back and forth.

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FP 35 back flips

Post  JMynes on Mon Aug 22, 2016 5:30 pm

Back in the 90s I was flying speed limit combat in New England. My favorite engine was the FP 35. We used to fill the tank, choke it a couple of times, give it a little squirt in the exhaust port, and check for a bump. Rotate the prop forward and wait for the start horn. When the horn blew we whacked the prop backward and it started first whack 99% of the time.
Of course, this was with a stock engine, no muffler, but it seems like you could come up with a similar one whack start routine by trial and error. Once you find the combination, you're golden.
Oh, and I wore a heavy leather glove on my whackin' hand. APC props will cut you!
Of course, now I give my start button a gentle push and stroll out to the handle. No leather glove required.
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Re: Prep for the Wildcat Rangers' next expedition

Post  RknRusty on Tue Aug 23, 2016 12:23 am

Hi Jim.
This fp used to be an easy first flipper, and it bumps after priming, though it takes about 6 choke flips. I have been meaning to check the spraybar hole position, and if it looks okay I will try another glowplug in it. Right now it's a fairly new Enya#3. It runs consistently really well throughout the flights, although I've had an air leak in the tank, and just found and fixed it. But I have not flown it since then. We're going out to the Fort on Thursday afternoon, so I can see the results of all my shop work since last Sunday. Hopefully, I'm through fiddling with it and can concentrate on practicing.
Rusty

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