C.G. question 1/8th scale

[Mike Stewart]

Where do I want the C.G. to be? It's at the back of sponsons in front of turn fin by 1/4" or close to it. Is that good? Boat was blowing over, I added 1 lb to left sponson 3/4 to right. Before I wasted another day at the pond thought I would ask here. Boat weighs 13 lbs. now. rear driver picklefork hull . Thanks any help is appreciated. Mike Stewart

 

[missbudpilot55]

Mi Mike,

I have the same boat, it is a R/C Sportscraft epoxy hull, I will get it off the self this evening & see where my ballance point is at. The only problem I have had with this hull is the turn fin, it wants to bounch in the turns, like the fin isn't working, have a new one on the hull but haven't tested it as of yet.

 

[Mike Stewart]

Thank you Bill. While you have it down would you mind measuring strut depth?

Not sure that mine is the R/C sportcraft, it was really rough hull with several twists here and there especially the transom, which was twisted by over 3/8" from one side to the other. Also the fin on the cowling looked like one of the killer whales with the bent dorsal fin. <_< <_< B) I'm also still looking for pic of it on the water. Anyone else wanting to give input feel free. Thanks.

 

[missbudpilot55]

Hey Mike is this the same Bud Boat.

https://www.intlwaters.com/gallery/displayimage...10084&pos=-1797

 

[missbudpilot55]

The CG on my 1980 Budweiser is @ 3 1/2" back from the rear of the sponsons.

My strut depth is 1 3/4" at the rear eadge and it is angled down @ approx 3 to 4 degress. Hope this helps.

 

[troymcintire]

Thank you Bill. While you have it down would you mind measuring strut depth?Not sure that mine is the R/C sportcraft, it was really rough hull with several twists here and there especially the transom, which was twisted by over 3/8" from one side to the other. Also the fin on the cowling looked like one of the killer whales with the bent dorsal fin. <_<   <_<   B)   I'm also still looking for pic of it on the water. Anyone else wanting to give input feel free. Thanks.

93897[/snapback]

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It wasn't one of mine (R/C Sportscraft). Not twisted like that. I wouldn't give something that twisted away for free. It would have hit the bandsaw. Troy

 

[Mike Stewart]

Troy I knew you wouldn't sell one like this one, it was pretty bad. :blink: :blink: Yes it is same U-12 Budweiser. I wish it was as nice as yours, thats a beauty. Originally I had c.g. 2" behind sponsons and it blew over at half throttle. It did same thing with 1457/3 prather 245 x457/3 x457/2 x455/3. I never got strut that deep though, tried anywhere from 1" - 1 1/2" deep. By angled down you mean kicked under hull to keep nose down? Thanks again, I sure hope to get this boat working.

 

[troymcintire]

How far forward of the transon is the center of the engine? Where is the CG now?

Is the driveline and engine centered in the tub or offset? How far forward is the Break in the bottom of the hull from the transom and whats the Sponson depth?

Sponson depth is measured by putting a straight edge on the strut plate (flat part of the bottom in front of the transom)and making a line continuing forward from strut plate up to the sponson transoms. Then put a straight edge across the back of the sponsons and measure down from the bottom of the straight edge to the line and that will give you sopnson depth.

The Oly I have been running has a sponson depth around an 1 1/8th and the strut is around an 1 3/16 at the front of the prop hub and an inch at the front of the strut (about 2 1/2 front to back) running a 255 with a Mac. CG is about 2 inches behind the sponsons. Troy

 

[missbudpilot55]

Hey Troy,

Could you post a picture of the turn fin on your boat as I am having a fun time trying to get mine right on one of your hulls.

Thanks...........