RC Boatworks Top Gun

[oscarel]

It was 35%, not sure what I was thinking but my math turned 1/3 into 30% somehow and adding receiver battery (2200mah 3s lipo) and Eagle tree equipment didn't help either. Temps on the motors were cold, as they were when it went out. ESC and batts were only slightly warm. I didn't have a current sensor hooked up but I will next time. Yes, bigger props are also next, since I'm running wire drives I don't necessarily have to run CR props, I'm thinking of running dual 447/3 since I've had good luck in the past with this motor and that prop. I tried trimming up but it didn't help at all.

[Jeff Wohlt]

You do know those couplers I sent were .093...correct? I see you posted 078 wire above.

That would not be good.

[oscarel]

Yes, I need to update. I have one .093 and a temp .078 that I'm using. Once the couplers get here I'll swap out the .078. Thanks for sending them!

[Jeff Wohlt]

Should be there today. Were sent priority on Tues.

[Fluid]

It was 35%.

My Stryker F-41 didn't run well at all until I had the CG between 32-33%. With the cat flat on a flat table, where are the struts? They should be either flat on the table or better raised at least 1/4" to 3/8" above the table. You can keep raising the struts until the props "blow out" or fail to hook up. Angle the struts up at the prop end 1 to 2 degrees. All the above will help to get the bow up and the hull running cleaner.

Temps on the motors were cold, as they were when it went out. ESC and batts were only slightly warm.

How long were you running? What was the ambient temperature? No temp gun? "Cold", "warm" and "hot" are terms so relative they are really meaningless.

I'm thinking of running dual 447/3 since I've had good luck in the past with this motor and that prop. I tried trimming up but it didn't help at all.

With twins you normally run a larger prop than you do with the same motor in a single application. Rather than x447/3 props try CRx457s. If they are too much, cut the diameter down to 55 or less. The prop walk you will get from two LH props will probably be terrible.



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[oscarel]

Another run today with current sensor, the 447's are not enough as it was only pulling 140 amps combined.

My Stryker F-41 didn't run well at all until I had the CG between 32-33%. With the cat flat on a flat table, where are the struts? They should be either flat on the table or better raised at least 1/4" to 3/8" above the table. You can keep raising the struts until the props "blow out" or fail to hook up. Angle the struts up at the prop end 1 to 2 degrees. All the above will help to get the bow up and the hull running cleaner. .

I set them between -2 degrees and +2 degrees with no change.

How long were you running? What was the ambient temperature? No temp gun? "Cold", "warm" and "hot" are terms so relative they are really meaningless. .

Approximately 5 mins on 6s2p paralleled to both motors. I do have a temp sensor that I'll hook up next time. I'm in the DFW area so ambient temps are around 70.

With twins you normally run a larger prop than you do with the same motor in a single application. Rather than x447/3 props try CRx457s. If they are too much, cut the diameter down to 55 or less. The prop walk you will get from two LH props will probably be terrible..

I bought a set of CR x457's today and I'll get them balanced and sharpened and go from there, thanks for the advice!

[oscarel]

Should be there today. Were sent priority on Tues.

Thanks Jeff, the showed up today!

[oscarel]

Fluid, what motor and prop did you end up with in your Stryker?

[Fluid]

I run a Lehner 3060/10 on 10S2P/9000mAh. I've run several props, the best were an x460/3 and an x465.

How high were the struts above the table? If they are too deep the strut angle will do nothing.

Watch the motor and ESC temps with the x457s until you know they are safe.



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[oscarel]

The bottom of the struts are 1mm from the bottom of the hull. I started with the ends of the strut touching the table as seen in this photo.

[oscarel]

fluid I just reread your post and the stingers are fixed at the transom, they can't be adjusted up only angled.

[Fluid]

I forgot you were using stingers. Not much you can do to adjust the prop depth without a lot of work. You'll need to move the CG back...why not just temporarily put the packs in the rear of the sponsons just to see if that gives you enough movement of weight. That or stack them crosswise on the tunnel two high. That will move the weight back too. Just be careful when testing to see if that frees up the hull. The bigger props may help too. I don't know of anyone who has used this hull for FE. I almost got one instead of the Stryker.



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[oscarel]

Well X457's made a huge difference. I saw 54 with a lot of porpoising so once it's trimmed and settles down it should do just fine. I ended up breaking the .093 shaft due to too sharp of a bend so I'm going to go back to the .078's for now and see if I can smooth out the prop shaft. I left the eagle tree turned on and lost all data, but after the first 2 min run which was not all full throttle the motors showed 90 degrees, I have the seagull unit so I didn't need to download the data. And of course I didn't look at amp draw...

[oscarel]

Quick update, due to the angle on the shafts I've switched to .187 flex which just came in yesterday. Also I've switched to Turnigy t180's and they seem to have a little more punch than the swordfish, also there are more timing options so I'll start playing with them once I make sure I can keep the shafts together.

[txboatpilot]

Sounds good Oscar! Cant wait to see it on the water..