My Psuedo-Moth is so cool!

Since my living room is so small, I was having a great deal of trouble hovering my stock Pic Fun, lots of crashes. As a result, I decided to build a moth following plans on John Kallas' web site. So far, I cut the blades by 60mm in length and 3mm cordwise, I was worried about adequate lift since I am running a 310 main motor and 50XC DD tail with a 3030 prop. I also cut the tail boom to 24cm. Everthing else is the same as stock, ie the flybar and paddles have not been cut nor has the landing gear. The hover is so much more stable, but the response is a bit slow, is this because of the stock flybar length and/or paddles? Shortening the flybar will increase response, but cutting the paddles will slow it back down right? Or do I have this totally reversed? Also the tail motor gets very hot, is this because I am running a 3030? Should I run a 3020?

I plan on eventually building a cdrom motor to get the headspeed higher and cut the blades smaller and building better landing gear probably out of piano wire. I've got my eye on getting this thing smaller and smaller. I love that tiny moth posted a while back with I think a 12 inch rotor span, who was that, Warren? My rotor span is about 15 3/4" Does anybody sell Moth sized carbon blades? Sorry about all the questions, I have a million more but I'm just rambling.

This thing is so much fun! Props to the Moth pioneers, John Kallas, JJ's moth page, and of course Warren's ultra-cool mini-Moth!

Thanks!
Ed

if you like e small have you been to marios site.

[dongle]

Pic would be good!

I've attached a picture.

Regards.. Ed

[JJ]

Cute Ed [img]/ubbthreads/images/graemlins/smile.gif[/img] another Mothaholic hm?
Shorter flybar slows cyclic response, paddles have less leverage. I have 175 flybar and small paddles, response is "lively" [img]/ubbthreads/images/graemlins/smirk.gif[/img]
BTW motor change won't change the headspeed but may change the throttle position, and the climb rate. Think about it, increase the headspeed is what you do to climb.

[R44]

Looks very good Ednigma!
Does a Moth fly different? And on what area's does it fly better/worse?
Last one: did you also shorten the main shaft? If not, can you shorten it?

Thanks,
Dave

Yeah another Mothaholic confirmed. When's the next MA (mothaholics anonymous) meeting. [img]/ubbthreads/images/graemlins/smirk.gif[/img]

I figured that a shorter flybar would slow the cyclic response due to less leverage, but what about the paddle size? Smaller paddles should also slow cyclic response?
Since you have a 175mm flybar, did you also leave the paddles uncut? I have the aero paddles that I think come with the ProPic (are they larger or smaller than the more squarish Pic paddles?) and they are contoured at the outer edge and have a symmetric airfoil, so it would have taken alot of time to make them smaller and exactly equal. Funny thing is that when I watch the rotor spin, the circles made by the tracking tape of the flybar and the rotor blades are almost the same size [img]/ubbthreads/images/graemlins/shocked.gif[/img]!

About the CDROM motor, I meant to say that I want to cut the blades further in length and chord, to get the head speed up for hover and I don't know how much more performance I'll get with the 310 (that's why I didn't cut quite as much off the rotor as JohnK suggests in his plans).

I was getting so frustrated by the instability of the stock Pic rising out of GE (remeber my flying room is very small with alot of furniture) that I first tried VCut blades and a 10T pinion. That stabilized the hover a bit, but I was still having alot of trouble hovering. I bought new blades and decided to cut Moth blades (several boom strikes prompted me to cut the tail boom). The first flight was so much more stable rising slowly out of GE. I was hovering for a record 15sec (a record for me!) and was so mesmerized that the Moth slowly yawed to a nose in hover without me noticing and I freaked out and crashed [img]/ubbthreads/images/graemlins/crazy.gif[/img]

Now I've got to learn more about CDROM winding and think about building a mount since I am "lathe-less"

Thanks.. Ed

Dave,

As I have said in other posts, my flying room is very small with alot of Pic attracting furniture. When I try to rise slowly out of GE, the turbulence caused my stock Pic to go everywhere but straight up. If I rise very fast out of GE, I can hover for a few seconds but turbulence would still push the Pic toward many immovable objects. So basically I was crashing and CA'in and adjusting the flybars, etc, etc.

I tried VCut blades which improved stability somewhat, but I was still having trouble. After cracking my tail boom, I finally decided to start building a Moth. As I said in my first post, I made a conservative Moth cut on the blades, cut the tailboom and added a GWS 50XC DD to the tail. The flybar and paddles are stock. The Moth is very stable compared to the stock and VCut Pics. I can rise slowly out of GE (I think it looks so cool and much more realistic to rise slowly out of GE) and hover for much longer than before. Well, 15sec stable hover is alot more than 5sec of unstable hover. I think I lose control with the Moth because it literally memerizes me during hover. Plus, I kind of like the smaller size, it seems to be in better proportions and seems sturdier.

I have not shortened the main shaft because I don't have the means to shorten the main chassis, ie the main shaft housing and bearing mounts. Someday, I may experiment by building my own chassis out of CF sheets. But first, gotta practice more... [img]/ubbthreads/images/graemlins/grin.gif[/img]

Regards.. Ed

Good job. I also cut mine down to moth recently, but just broke my blades. Guess I'll have to get some new ones. I will be leaving mine moth size, because of the stability I get. I like that, but you have to be careful hitting anything with it. You hit anything with the head speed up, it will do in the blades. I love my moth though.