Wild Thing Nearly Ready For The Pond

[Curtis Beaumont]

Alright,

After all of this I am balancing the boat and it is coming in very nose heavy. I did some things with the top deck and I believe I have extra weight in the front due to over use of epoxy and glass up there. In order to get it to a CG of 9.5 Inches from the transom, I need about 14 oz of lead in the rear. Now, the question is this... Should I leave it for now and add the weight incrementally if I need it? Should I get it as close to 9.5 now and tweak it, or is 10.5 (33%) a good number and possibly make the boat handle well? I made a rear compartment that separates the transom from the rear radio box bulkhead, which is about 3/4" wide, but the lead would nearly fill this up.

Let me know your thoughts,
Curtis

 

[seaducerpete]

Ive always heard that cg should be around 33%

 

[David Ashcroft]

Avoid adding weight if possible,,,best thing is to move the internal bits and pieces fore n aft to get your desired CG,,for future reference place all items in hull and measure CG then secure,,, other than that just throw her in and have fun testing..

 

[John Finch]

Curtis,

Adding weight won't hurt your boat. Better to have the right CG. While 33 percent is ok with a seaducer it is too far forward for most mono designs. 29 to 31 percent is the range that you should shoot for on most mono hulls. This one loves to be about 30 percent. If when the boat airs out the nose drops, add weight to the transom. If the CG is too far forward the boat will stuff or swap ends when it hits the water after leaving the water. I tried 32 percent on my 34 inch wild thing for SAW and it swapped ends when the bow dug in after letting off the throttle. I changed it to 31 percent and the boat glides on top of the water and settles down smoothly when I let off the throttle. Let us know what you find out with your boat.

John

 

[Curtis Beaumont]

Thanks John,

I'll try out 31 percent at first and see what it does.

I appreciate the help.

C

 

[David Bryant]

please post an image of your new Wild Thing if you get a chance Curtis

 

[Curtis Beaumont]

sure, here it is. It was made from plans, vs. the kit and I took some liberties with the build (beveling the deck, changing the v-angle of the bottom, etc.)

 

[eekern]

Looks great curtis.....hopefully Jullian will have his seaducer ready to give you some competition.

 

[BobBonahoom]

Curtis,

Mine came out at 10" or about 31%. I assume John's number recomendations are without fuel.

To get it to 30% I had to move the battery from the left front to the right rear of the radio box. I also added 2 oz of lead on the rudder bracket. See pics.

Now I see perhaps another problem. The pipe, battery, strut, and added lead weight are all on the starboard side of the boat. This will add to the torque twist and make for a deeper right trim tab to keep it from listing. (I am guessing at this though, since I have never run a mono before). I think I will move the battery and weight to the port side of the boat to try and improve side to side ballance - John, does this make sense?

 

[Curtis Beaumont]

Finally, a picture of my boat with it's namesake. This is my little girl, who happens to be 4. Her name is Hazel.

Hope you like it.

C

 

[ALLAN YUEN]

Fool in Happen !! Show picture of Mark Anderson blew out hole because he forget put glued carbon fiber cover inside engine area

 

[John Finch]

Curtis,

Mine came out at 10" or about 31%. I assume John's number recomendations are without fuel.

To get it to 30% I had to move the battery from the left front to the right rear of the radio box. I also added 2 oz of lead on the rudder bracket. See pics.

Now I see perhaps another problem. The pipe, battery, strut, and added lead weight are all on the starboard side of the boat. This will add to the torque twist and make for a deeper right trim tab to keep it from listing. (I am guessing at this though, since I have never run a mono before). I think I will move the battery and weight to the port side of the boat to try and improve side to side ballance - John, does this make sense?

I see you have the pipe on the port side now. The battery would go well on that side as well. You are thinking all in the right direction.

John

 

[BobBonahoom]

Thanks John,

Actually, I have my pipe on the starboard side. (Curtis has his on the port side). I have moved my battery and lead weights to port.

 

[Curtis Beaumont]

John, I also assume it is a good thing to keep the weight low, but that is merely an assumption. Would you recommend keeping it down on the keel?

Thanks,
Curtis

 

[John Finch]

Low is always better.

John

 

[Sean Wills]

Curtis your daughter a cutie! And the boat looks nice too

 

[Curtis Beaumont]

Thanks,

I'm proud of both of them. My daughter much more so.

C

 

[Grimracer]

Just looking at the pic of you boat Curtis.



Maybe you have done some of this allready,, but

I have the same motor and really like it.. Keep in mind the included carb is a tad large for a 21 boat. After you have some time on your boat start looking for a smaller bore carb.

The header looks like a wide radii unit. You FOR SURE want the short. Glen Q on here can get you the right header (nova will work).. Get a pipe tool from Woods racing to set the lenght.

The plug cap.. I like and use mine BUT.. have made a keeper that holds that cap in place. At speed it can blow off.

Also.. (Im sure you have thought of this).. might want to get a muffler for that pipe.. On a mono its hard enough to keep the noise down (guitar body boat)



Looking forward to seeing it run this summer



Grim

 

[osracer]

Curtis

The pipe I offered to you is a quiet pipe I don't remember what kind but my mono with an OS RZ ran like Jack the Bear with it. I also have an OS20G carb you can have. Not sure if will fit or not but think it is what you are looking for. Grim can probably jump back in and let you know. The pipe measuring tool is for the nova header, it is one that Grim used to make.

Bill

 

[Curtis Beaumont]

Thanks you guys,

Since I took that picture, I swapped out the carb for one from the OS outboard I had laying around as a spare. I also grabbed an NR header and shortened it up a bit. I think I am at about 8.75 so far, with the dremel ready to go to cut it down. I didn't realize about the muffler, but I will connect with Bill and look into mounting the quiet pipe. I didn't realize about the keeper. Do you just tether it to the boat, so you don't lose it, or actually keep it from coming off the head of the engine, so you don't loose the cooling? I am considering changing the route of flow, so the head plug is the return line that leaves the boat, not the intake.

Thanks for your help you guys.

Bill, are you planning to be at the speed run next weekend? I will, maybe that would be a good time to connect and get those parts from you.

Thanks again,

Curtis