CF 3.5 Rigger Project

[MikeP]

Hammer,

My CG is at 25% about 3/4" to far forward. I could adjust some radio gear around the fix it. That puts my turn fin trailing edge even with the CG. Would I move it back as well?

Thanks for the tips on taping that works good.

I got a 1445 prop to try should be close.

Any suggestions on strut height and angle.

-Mike

 

[Hammerhead]

I have some info for you, could you wait until tonight. I have to go to work now.

Hammer

 

[Hammerhead]

HI Mike! Thanks for the chat! This is what I was talking about in ICQ.

Pics are worth a thousand words.

Good luck! Hammer

 

[MikeP]

Hammer,

Ok double checked the front and rear, set the strut eveything is perfect.

I have an idea on the front sponson tubes (see below) tell me what you think.

Thanks,

MikeP

 

[Hammerhead]

Hey Mike!

After you glue that on, you will use electrical tape to tape over it, won't you? That is a pretty cool set up. What are you going to make the pieces out of? Carbon? Kevlar? Aluminum? Let me know how it works. It has to be better than building up the tape.

Hammer

 

[MikeP]

Hammer,

I can't turn a 1445, cavatates then bogs. I got a 1440 to run but it lifts the back and pushes the front end in slowing it down. I got more speed with a prather 220. Didn't have a 225. A prather 230 was too big. It really likes prather and x series Octura props the way the hull is setup. Wondering if my sponson height in the rear is wrong. It's set level with the front. Maybe a little lower in the rear would be better for running hydro props. It runs great now with the strut adjustments. It's getting there a little at a time. ;D

-MikeP

 

[p. mull]

Mike I have the same basic design rear sponsons. I run

my strut half way below the rear sponsons with a 1 degree

neg. angle. And it will pull a 1445 pitched up.

 

[MikeP]

p. mull,

Is your rear ride height on a setup table lower in the rear than the front?

Mike

 

[Hammerhead]

With my 90 hammerhead, the front sponsons are about a half an inch higher than the rear. Might be a problem. I don't know.

Hammer

 

[p. mull]

Mike

When the boat is sitting on the table it is sitting on the strut and on the rear edge of the front sponsons. The top

of the tub is level.

 

[TomMoorehouse]

Mike... can't say for sure with a rigger made the overseas way that it will be exactly the same...... but i would start with your sponsons 1/16" above your setup table to start... then work up to as much as 1/4"-3/8" off the table.

 

[MikeP]

I was reading some tech notes on rc-boat.com. It seems that strut weight has alot to do with prop selection, less strut weight needs x series props. I was wondering if anybody knows what the weight would be for light or heavy strut weight on 3.5 riggers.

-MikeP

 

[Mark Sholund]

Mike,

That is not true about the X series props. The 14 series props are the way to go I believe.You can do so many more modifications than with an X series prop.I think prop wieght is important so I will measure mine on my carbon 21 and get back to you.

Thanks

Mark Sholund

[email protected]

 

[MikeP]

Mike... can't say for sure with a rigger made the overseas way that it will be exactly the same...... but i would start with your sponsons 1/16" above your setup table to start... then work up to as much as 1/4"-3/8" off the table.

Thanks Tom, It looks like this is the problem, I think it should be set up like any 4 point hydro. I don't know what I was thinking when I set it at 0".

 

[MikeP]

Wahoo i'm swinging the big props.

After alot of changes I got it going.

Threw away the OS 2d and ran a OS 4E. (Per Hammer)

Made new rear sponsons 1/8" lower with powdered graphite in the epoxy, block sanded them to get smoth sharp edges.

Replaced the strut with one that extends the prop out past the rudder and has a round bottom.

Sharpend and polished the rudder and rounded the bottom edge.

Launched easy first try with 1445.

Thanks,

MikeP

 

[ggillman]

Way ta go Mike!!!! Yah Hoo !!!!! ;D ;D ;D

That rigger even looks more wicked on the water, excellent pic by the way!!!!!

Gene ;D

 

[Hammerhead]

Way to go Mike!

After all the hard work and long hours you put into that boat, it sure must feel good to see it running like that.

Hammer

 

[Mark Sholund]

Mike,

Sounds like you got the boat running good.Now try

adding some pitch to the 1445 prop and you should

be all set.Have Andy Brown pitch you a 1445 to 3.1"

and you will be happy I bet.Next buy a MAC 21 for

your boat and you will be really FAST.

Thanks,

Mark Sholund

 

[Hammerhead]

Isn't it a Mac .21 that you are running Mike?

Hammer

 

[MikeP]

Mark,

How do I pitch to 3.1? I am running a MAC .21 really love that motor. Has anyone tried a J&D carb on a MAC 21?

MikeP