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Jesse J
07-27-2009, 11:14 PM
I am hoping I can get a little feed back on why my cat might be doing such impressive flips.

This is a 27" balsa/ply cat scratch built by me from Shockerman plans. I have a Proboat motor with a Turnigy 100 amp HV ESC with water cooling. This run here spins an X640 on 6S.

I am wondering if I might need to back off to 5S? or smaller prop?

CG is right about 33% and strut is about level with base of sponsons with 3deg positive? (bow up). I am working with a strudder these runs (the one from OFE) with a .062" wire drive. I am also wondering if she is too light, maybe 3lb.

Any ideas would be nice. The batteries are sitting kinda high and might be contributing to the rolls at lower speed, but the nose-dives are kinda weird. I would expect blow over, but nose divez?

http://www.youtube.com/watch?v=ylqJvX1Y9qw

Hey Peter, how's this for a little better "entertainment" grade moviemaking? :w00t:

Fluid
07-28-2009, 02:00 AM
Several thngs to try:

- Raise the strut, try it with the bottom 1/4" above the sponson bottoms and flat. Use a flat table, don't try it 'by eye'.

- Move the CG back to 32%.

- Try an x440 prop.

- Try adding 8 ounces of lead low in the hull at the CG.

- 5S is an option....



.

Punisher 67
07-28-2009, 02:18 AM
Awesome video Jesse , man that little sucker really hauls :moon:

LiPo Power
07-28-2009, 02:23 AM
Hey Jesse
Could you please be more aware next time?
These are Canadian Geese ok..... We need them back when they finish fertilize all the green easy to walk at the moment grass arround the homes.... :tongue_smilie:

Tunda
07-28-2009, 04:11 AM
Jesse you need to run her in a bigger pond..........

Jesse J
07-28-2009, 08:28 AM
Thanks Jay, will try those ideas.

I am aware, Robert, that these are the buggers who COVER the sidewalks with this "fertilizer" so running them off has actually become encouraged here in Denver area.

Tunda, the problem with a bigger pond is that I have to cast farther with the retrieval rod to recover the upside down kitty.

You like Peter? Figured you might get a kick out of some tunes.

Jesse J
08-03-2009, 12:14 PM
Well I incorporated all of Jay's comments AND backed off to 5S. I think she is about right now. The only thing is she gets a little wobbly at speed on anything but glass. Would this be strudder related?

This is a short one and no tunes, sorry bustit and Peter, in a rush and wanted to get this out as an update. Will get some better/longer footage soon. I need to get my rx pack more secured, it came loose and got all wrapped up in the drive line.... I know, rushing to get it on the water. I did, however, put some shots of the rear end in there so you can see JUST what is making this thing move. I have a CC 120 in there to handle the higher than Proboat-standard amps, but the motor is still the same proboat guy.

http://www.youtube.com/watch?v=sh66NNFDDSE

Jeff Wohlt
08-03-2009, 02:48 PM
Damn dude...and with one of my 62 wires! Guess loctite is stronger than solder! Looks like one of my older SS struts with bearings.

I have your other drives going back out shortly. I really think you should stick with 78 myself.

And YES, the inline rudder can play hell with handling in prop wash

Holy cow...on the 5S is did a 360 roll and still landed right!! That was cool!

sailr
08-03-2009, 03:42 PM
Man! She cooks. You need a bigger lake! I'm wondering if that long rudder is causing you some handling problems. When the boat gets airborne a bit the rudder is still hooking up...throwing you off. Not sure. I'm no expert in that area. Just a thought. Anyone else think the rudder is a bit too long?

Jesse J
08-03-2009, 03:52 PM
These are the exact reasons i am soliciting comments! I have a rudder I could throw on the side.

Yep, Jeff, she did at LEAST a 360 if not twice barrel roll and landed wet! This did knock loose the rx pack and man that was a mess.

She gets wobbly at speed. Well, I can try adding a rudder and just remove the inline one from the boom without too much trouble.

Too long of a rudder? anyone else have this idea?

Yes I do have a bigger lake, but for a 15 min break before and after work that is 5 min walk from the garage, you can't complain much (that is if you aren't water fowl).

sailr
08-03-2009, 03:53 PM
Man, I hear ya about that 5 minutes to the lake! Looks like a beautiful development you live in! In your second video it looks like the lake is longer than I thought! :bounce:


These are the exact reasons i am soliciting comments! I have a rudder I could throw on the side.

Yep, Jeff, she did at LEAST a 360 if not twice barrel roll and landed wet! This did knock loose the rx pack and man that was a mess.

She gets wobbly at speed. Well, I can try adding a rudder and just remove the inline one from the boom without too much trouble.

Too long of a rudder? anyone else have this idea?

Yes I do have a bigger lake, but for a 15 min break before and after work that is 5 min walk from the garage, you can't complain much (that is if you aren't water fowl).

Jesse J
08-03-2009, 04:38 PM
Google Earth says it is over 200' in most directions. I do have the fountain to avoid and the walls are cement, so better to avoid them too. Ducks tend to clog the prop but they are getting the idea that it is better to avoid me.

I will try to get a shot this evening after they turn off the fountain. It would be perfect for mini racing...

Punisher 67
08-03-2009, 04:42 PM
Was just thinking the same thing as Jim , that certainly is a beautiful neighborhood you live in Jesse.................:smile:

Jesse J
08-03-2009, 04:49 PM
We LOVE it. Too bad it is only for this summer while I work on my "mentorship" for my research. We head back to Bozeman at the end of August...

bustitup
08-03-2009, 04:51 PM
I like it.....super nice build

the music was awesome too...I acually stayed awake this time


the only thing I didnt like was how you past up all those points...those ducks are easy ten pointers one of them was maybe a 15...must have been the mother

Jeff Wohlt
08-03-2009, 05:03 PM
I think if you add some weight it will be faster.

bigpapa
08-03-2009, 05:13 PM
Jeff i also Run a .062 wire in my Intruder S at 58.4 mph and it has never let go either, AWSOME RIDE JESSE , AWSOME BOAT GREAT JOB AND HAVE FUNNNNN......

:bowdown::banana::bowdown:
:tiphat::tiphat::tiphat:

Flying Scotsman
08-03-2009, 06:02 PM
Jesse, it looks like a balance, weight problem and maybe too much voltage. A very neat looking boat and we can send you some more fowl if you wish.

Douggie

AntronX
08-03-2009, 06:07 PM
http://www.youtube.com/watch?v=ylqJvX1Y9qw


Are you speeding up your video during straight passes?

Jesse J
08-03-2009, 06:32 PM
Are you speeding up your video during straight passes?

Yes, that would be quadruple time. I am glad you noticed...:sarcasm1:

No sir! this is real beans. :thumbup:

Thanks for all the enthusiasm guys, and Douggie, I need no more foul in my waters.

I am going to try first an offset rudder; I still have my aluminum plates in place for solid attachments. I can report back with actual weight - it is rather light, but lemme slapper on the scale n get back with accurate measurements, not precise guesses.
:beerchug:

Jesse J
08-04-2009, 12:13 AM
Got a chance to run just before dark. Ran grEAt!! wanna get some vid of her opened up full throttle for some good long runs. Anyway, I get the idea that I am close with the set up and have the rudder ready to try.

http://www.youtube.com/watch?v=LZV0woENDRU

wolf IV
08-04-2009, 12:27 AM
Awesome jesse!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!! She rides perfect. Almost lost her towards the end, good recovery!

Jesse J
08-04-2009, 08:05 AM
That's the fun of this one, she is on the edge of lettin loose for reals, but then back off a touch and she recovers nicely. She is actually quite aerobatic... and is learning it's best to land wetside. You liked the wheelie? me too.

Jesse J
08-05-2009, 09:49 AM
Got her out on some chop and she looked pretty good. She is on the border of blow over, but this also keeps her loose and fast. I think this is the set up that works best.

Any tweaking suggestions are always welcome.

http://www.youtube.com/watch?v=o5SArsmSZjg