Deep Vee chine walking question

[David vanmaris]

keep in mind that to put the prop at 1/8 to left can prevent propwalk, sometimes just to much power for hull size though can cause the chine walk, try smaller diameter props with pitch,and also experiment with rudder depth only slightly, also tabs and turn fins, have fun experimenting.

David AMPBA370

 

[Steve Anderson]

First of all, I have no experience with monos.

Second, if you want to learn about monos use the advanced search here and put the name John Finch in the find author line and learn away.

I think you will find John recommends having the shaft come out of the transom on the right side but the strut angled left 2-3* so there is left thrust but the prop hub centerline is centered or a little to the right of the hull centerline. Weight in the boat centered.

Lastly, monos riding on plane don't have the benefit of a wide stable platform. It's a balance of the air pressure under the hull to the right and left of the planing area, the prop, and the rudder upward and any trim or turn input force. The short story is the forces don't maintain the balance on a mono from 0-top speed so it will do crazy thing at some speeds and power settings. Gunning it, as you said, adds even more roll force to the hull than in a steady state so slower smooth throttle change will help it stay balanced.

 

[John Finch]

I have been modifiying one of the traxxas spartans. Leopard 4082 1500Kv, T-180 esc, S+B+P M645, Speedmaster dual pickup rudder, etc,

I am having issues with chine walking above 55mph.

It has been suggested that the strut & stuffing tube being mounted at the lowest possible point in the bottom of the Vee is causing the boat to become more unstable at higher speeds because its to hard for the boat to balance on the tip of the vee. And that moving it up about 1/8" will help. That makes sense.

The boat also seems to want to torque roll. I have shifted the weight in the boat so the port side is slightly heavier. This seems to help at lower to med speeds. But still when the boat gets up to WOT it will still turn and start to chine.

So I looked up some stuff and found a few websites saying that if you offset the strut to the right starboard side about 1/8" this will help counter torque roll in Vee hulls.

I just finished modifying & moving my stuffing tube and strut up about 1/8" and over a little less than 1/8"

But I am hearing conflicting info about moving the strut over to the starboard side. Can any one shed any light on this about moving the strut over to the right to help counter torque?

Thanks

Things to consider.......offsetting the strut to the right helps fight torque to a certain speed. When you get the boat super loose, you need the strut in the middle of the boat and the rudder is then your anti roll controller. Trim tabs are brakes. They calm the boat but you lose speed too. raising the strut up lets the boat settle into the water to gain control. Weight should always be in the centerline of the boat. Back to the rudder...........when your boat is going faster than original design the rudder is your controller. The rudder lifts the boat where it is mounted. Closer to the keel and the boat rolls to the right. Further away from the keel towards the starboard side of the boat and the right side of the boat lifts. Get it in the right sweet spot and the boat tracks straight. This location is determined by the speed and lightness of the boat on the water, so you need to compensate more or less as the boat goes faster. Most boaters don't get to the speed where the rudder is the trim device, so consider yourself getting the most out of your boat and leading into seldom approched areas of trim. I learned this from countless years of record trials with mono hulls that ran way past their designed speeds. This is secret info by the way, so don't tell anyone. LOL There is also more dynamics to the rudder setup that affect trim, but this will get you started in the right thought process.

 

[hugh hargett]

A square bottom strut may help too.

 

[John Finch]

Now ive heard two different stories about offsetting the strut 1/8 ive heard set it off to the right and the left.

Read down this page it says offset to the right

rc boat hull attitude

and i read it here

deep vee setup

im not liking the internet anymore lol.

That's the problem with anyone posting. Everyone has ideas, but how many people really know the full story. Having the strut to the right of centerline lifts the right side of the boat to counter act the torque of the motor that rolls the boat to the right. BUT, if the rudder causes a lot of lift, it might work better if the strut is a little to the left of center. The problem is.......everyone has different boats at different weights, and different rudder and strut locations etc. What works for one guy most likely will not work for another. There are few people who understand ALL the dynamics and even the best and most knowledgeable cannot read a few words on the internet and say with certainty what needs to be done to fix a problem on someones boat without seeing the boat run and actually driving the boat to get a feel for what is going on. The internet is good for sharing ideas, but the modelers have to put those ideas to the test themselves. All the knowledgeable people can do is point out the cause and effects of hardware. Unfortunately some keyboard racers will thow you off the correct path because they really don't know the cause and effect. Better to get into a club and latch onto the old fart who has been there tried that and can help you out in person. That's why IMPBA and NAMBA organizations were formed. To help the newbies and promote model boating! Join one of the organizations and meet modelers face to face if you really want an education.

 

[Charles Perdue]

Now ive heard two different stories about offsetting the strut 1/8 ive heard set it off to the right and the left.

Read down this page it says offset to the right

rc boat hull attitude

and i read it here

deep vee setup

im not liking the internet anymore lol.

That's the problem with anyone posting. Everyone has ideas, but how many people really know the full story. Having the strut to the right of centerline lifts the right side of the boat to counter act the torque of the motor that rolls the boat to the right. BUT, if the rudder causes a lot of lift, it might work better if the strut is a little to the left of center. The problem is.......everyone has different boats at different weights, and different rudder and strut locations etc. What works for one guy most likely will not work for another. There are few people who understand ALL the dynamics and even the best and most knowledgeable cannot read a few words on the internet and say with certainty what needs to be done to fix a problem on someones boat without seeing the boat run and actually driving the boat to get a feel for what is going on. The internet is good for sharing ideas, but the modelers have to put those ideas to the test themselves. All the knowledgeable people can do is point out the cause and effects of hardware. Unfortunately some keyboard racers will thow you off the correct path because they really don't know the cause and effect. Better to get into a club and latch onto the old fart who has been there tried that and can help you out in person. That's why IMPBA and NAMBA organizations were formed. To help the newbies and promote model boating! Join one of the organizations and meet modelers face to face if you really want an education.

AMEN....NOTHING BUT GOSPEL!!!!!