Genesis skittish at high speed

[Prop-a-Gator]

Any updates on the tuning Matt? I got my Daytona out this evening. It still looks like it's running wet at 28% (9-1/4"), but it's moving on 6s. I'm guessing mid to upper 50's. Got to run it from a canoe dock on a big lake where rc boats are allowed! What a difference to be able to open her up. I will move COG back some more to see where the limit is. My Daytona is prob a little nose heavy because I reinforced the tips with extra glass and resin.

[izcain]

It's wierd how different two identical hulls will take to get them setup ok. I reinforced mine as well but I also have a couple layers of kevlar throughout the boat so maybe that is the difference. I even have a bunch of floatation stuffed up into the top as well.

[Mattwarner]

Hi Guys, ive ordered an M445 prop and going to raise the strut slightly but need to do some work as it wont go any higher, however ran it last night with the cog around further forward (will work out the " later as i didnt have a ruler) and it ran much better, i am also going to make a standoff to offset the rudder and just fill in one of the holes for the rubber boot.

[ozzie-crawl]

Building a twin cat but whilst waiting for funds to finish thought i would do a bit of work on a hull i have had sitting awhile.
Decided to offset rudder (same rudder as yours) Found a old motor mount had the same distant apart screw holes. mite not be perfect but very cheap fix

[izcain]

I think you will be pleasantly surprised on how it reacts with a prepped m445 on the back.

I think I am going to try one of bens offset rudder kits from fightercat. I could make one but I dont have the time right now!

[Prop-a-Gator]

Matt, I've seen some use motor stand offs to offset the Genesis rudder. Like this:
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=6290
I don't know how durable they are.

Can you seal the boot hole temporarily until you run the offset rudder? You have a very clean looking boat with the push pull rudder. I'd hate for you to change it and find the offset doesn't help your issue.

I offset my rudder but I had very little before to compare to after. I just wanted to. Here's mine:

[ozzie-crawl]

OSE has these http://www.offshoreelectrics.com/pro...rod=oct-oc4off there 28mm were the hk ones are only 20mm.
even tho the prop will be set back a bit the rudder would still be very close to the prop wash (using a 45mm prop)
Being there is already a hole for the steering if you measure center of rudder to the rudders arm hole (20mm) then double that so you pickup the left side rudder arm,you would want the center of strut to center of rudder to be 40mm.
If that makes sense. the right servo rod lines up with the left rudder arm hole if the center of strut and center of rudder are 40mm apart.

[carlcisneros]

Ozzie;
those are the ones i use on my daytona and they work great.

[ozzie-crawl]

Ozzie;
those are the ones i use on my daytona and they work great.

Good to know. I was thinking 28mm plus 4-5mm to center of strut, 4-5mm to center of rudder and your dam close to that 40mm center to center

[ozzie-crawl]

Double post

[JonD]

OSE has these http://www.offshoreelectrics.com/pro...rod=oct-oc4off there 28mm were the hk ones are only 20mm.
even tho the prop will be set back a bit the rudder would still be very close to the prop wash (using a 45mm prop)
Being there is already a hole for the steering if you measure center of rudder to the rudders arm hole (20mm) then double that so you pickup the left side rudder arm,you would want the center of strut to center of rudder to be 40mm.
If that makes sense. the right servo rod lines up with the left rudder arm hole if the center of strut and center of rudder are 40mm apart.

Sorry, but I don't quite understand how this OSE part is used to offset the rudder. Can someone post a photo of a boat set up with offset rudder using this part, please?

Jon

[JonD]

I offset my rudder but I had very little before to compare to after. I just wanted to. Here's mine:

Hi Prop a Gator,

With the offset rudder to starboard side, do you find that the extra drag on this side causes the boat to want to veer right noticeably? Reason I ask is that other threads have suggested that an offset rudder is better placed on the port side as this would help compensate against prop walk which also tends to want to make the boat veer to the right. But with the Gensesis where the rudder servo is already on the starboard side it certainly makes for an easier mod to put the rudder on the starboard. I am planning to offset my Genesis rudder but am undecided which side to put it on. Starboard is certainly easier, but if this tended to make it veer right more, I guess I would be inclined to go the extra mile and put it on the other side.

Jon

[Prop-a-Gator]

Jon,

Yes, good point. My boat had a tendancy to veer right when I had the inline strudder. When I blew the ESC, I decided I'd offset the rudder while I rebuilt a few things. I read quite a few threads that advised to offset to the starboard side. Quite a few veteran boaters/racers and a few fast videos - all starboard - with some explaining that it is better at counteracting prop walk. They also cited moving the rudder out of the thrust cone and allowing larger diameter props than the strudder. Well, my boat still has a tendancy to veer right - though only slightly. I still have to sort it out. I've been trimming my rudder to go straight, but that slows you down. I should add that those same threads also advised to have the rudder adjacent to the prop. Mine is set back a little.

I have also had a recent discussion with a very experienced boater who told me offsetting the rudder to address prop walk is a myth. The only reason to offset the rudder is to move it out of the thrust cone/prop wash. It does have benefits, but not for prop walk. He says the reason most people offset to starboard was to help the boat turn right for racing. In the early days, servos were weak and boats couldn't turn left well due to prop walk, so they raced clockwise. Offsetting the rudder to the starboard side on vee bottoms helped keep the rudder in the water during turns while racing. He agrees with you. If anything, the added drag from the rudder would tend to make the boat veer to that side - so it makes more sense to offset to the port side. I hope he doesn't mind me paraphrasing his words.

I'm pretty committed to the rudder installation now. I'll update if I find the culprit or a solution that does not involve trimming my rudder to the left.

[ozzie-crawl]

Cats as far as i have ever seen are on the starboard side. Think only hydros run on the port side.

[Mattwarner]

m445 arrived today! got her bolted on and raised the strut slightly so its about 5mm off the table, I am also planning to use some 60mm long m3 bolts and brass tubing to make the standoff, will post some pics and results after i try it