rudder spacing?

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DIXIENOURMOUS
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rudder spacing?

Post by DIXIENOURMOUS » Sun Aug 14, 2011 11:32 pm

well first day out on my first boat and tried to make a turn and ended up in a tree. i was makin the turn at 2500 rpm's turned the rudders and it really didnt turn so i revved it to 3000 and it just made me get in the tree faster lol.the boat slid side ways in to the tree but i really had no control
the boat is a PE 60 aluminium hull with a 3 blade warp drive and the rudders are real close to the hub should i move them apart?
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Re: rudder spacing?

Post by Whitebear » Sun Aug 14, 2011 11:51 pm

My bet is your still on the learning curve. You got a cheap lesson if you didn't tear the boat up. Remember when there is no air being blown over the rudders you are out of control unless your sitting still.

That blast over the rudders will get you turned but then you have to dig into it to get the boat to to begin to change directions. The trick is to learn how to make both happen seamlessly. Just like a race car, you should be accelerating through and OUT of turns. Now that don't mean going fast or haulin a$$, it means accelerating. Never cruise the boat faster than it has the power to power out of a turn or emergency situation.

Find ya some skinny water with no obstacles around and get some slow speed practice. Move up as your skill progresses. Also it would be good to get with an airboater friend and have them around for pointers and for a safety man, just in case. Likely at this point there is not much wrong with your rudders, just learn how and WHEN to use them. You can work on the boat mods much later.
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Re: rudder spacing?

Post by DIXIENOURMOUS » Sun Aug 14, 2011 11:58 pm

i know air needs to move over it rudders but can they be to close together? i have been driving fanboats for a little while and know some stuff

my buddies don davis fast boat wont turn unless rev it up but this thing has a hard time turning even if you rev it
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Re: rudder spacing?

Post by theairboater » Mon Aug 15, 2011 12:14 am

Hi Dixie,Go out and try spinning brodies with that boat.That's how i learned what the boat wanted for turning.Just a thought.Some folks in fairbanks will say i still haven't figured it out after 15 + years in the swamps.

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Re: rudder spacing?

Post by Whitebear » Mon Aug 15, 2011 12:17 am

Not knowing your boat I cant make a statement about rudders on it. Spacing generally runs between 18 and 22". Generally the prop is about a soda cans length in front of the transom and some dip that much below the transom and others run totally above the transom. This is all very GENERAL and likely will at least give ya a range.

Might get more/better input with some good pictures posted, &/or detailed measurements.
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Re: rudder spacing?

Post by DIXIENOURMOUS » Mon Aug 15, 2011 12:26 am

ill get photos tomorrow
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Re: rudder spacing?

Post by djh0405 » Mon Aug 15, 2011 12:30 am

If you slid sideways into the tree it sounds like maybe you didn't straighten the rudders fast enough. The longer theyre turned the more the ass end is going to slide sideways. If the boat isn't turning good it could be rudder spacing. Are they turning and the boat doesn't change direction or are the rudders just not turning like they're supposed to? What kind of rudders are you using and what size?

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Re: rudder spacing?

Post by Smuggler » Mon Aug 15, 2011 5:58 am

Here is a Rudder spacing formula... Length of prop divided by 2 minus 10= rudder spacing.. That should put you right on the money :D

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Re: rudder spacing?

Post by MYDIXIEWRECKED » Mon Aug 15, 2011 6:35 am

Smuggler wrote:Here is a Rudder spacing formula... Length of prop divided by 2 minus 10= rudder spacing.. That should put you right on the money :D
Sounds about right. I run an 80 inch prop and my rudders are 28" apart. I didn't have the formula but got in a good guess! LOL
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Re: rudder spacing?

Post by watersports7 » Mon Aug 15, 2011 6:41 am

Smuggler wrote:Here is a Rudder spacing formula... Length of prop divided by 2 minus 10= rudder spacing.. That should put you right on the money :D
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Re: rudder spacing?

Post by harley » Mon Aug 15, 2011 7:51 am

that's all good info on rudder spacing, and like Whitebear said , you might just need so more stick time to learn some more on how to controll your boat in your turns.. it's is best to find some open skinney water and do lot's of different moves with your boat, that is one of the best ways to learn your self ,you just may need some more stick time, bro... 8)
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Re: rudder spacing?

Post by DIXIENOURMOUS » Mon Aug 15, 2011 1:16 pm

i cant get the photos to load (file to big) but the rudders are 48"x24"
space between them 25"
prop 60"
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Re: rudder spacing?

Post by djh0405 » Mon Aug 15, 2011 1:52 pm

25" isn't too far off, but might not hurt to bring them in a little. I think mine are at 24". Are you sure your rudders were turning completely? Are you set up with a cable or dog leg steering? Boat could be fine, maybe you just need to get used to it. Not tryin to say you don't know how to drive one, just sayin not all of them handle the same.

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Re: rudder spacing?

Post by DAVE C » Mon Aug 15, 2011 6:05 pm

by some chance did you end up with a step hull as your first hull ?

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Re: rudder spacing?

Post by glades cat » Mon Aug 15, 2011 6:21 pm

Rudder spacing formula=swing that azz end around and stand on the gas if you want the boat to turn....untechnically speaking.
Speed too fast for conditions.
Them things'll drift 'n slide sideways like a son of a gun.
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Re: rudder spacing?

Post by GladesAirboat » Mon Aug 15, 2011 8:56 pm

Yep, sounds like those darn trees came from nowhere, LMAO been there done that. To many variables to just give a blind suggestion. Deep water, Shallow water, Speed, my favorite not enough time to correct the darn thing. When you go into a slide things happen quick.
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Re: rudder spacing?

Post by DIXIENOURMOUS » Mon Aug 15, 2011 10:56 pm

its a flat bottom deck over with sharp edges on the sides
i hit the trees did a 360 and continued on like nothing happened cause i was hoping no one seen me but my buddie did.
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Re: rudder spacing?

Post by djh0405 » Mon Aug 15, 2011 11:08 pm

DIXIENOURMOUS wrote:its a flat bottom deck over with sharp edges on the sides
i hit the trees did a 360 and continued on like nothing happened cause i was hoping no one seen me but my buddie did.
:lol: :lol: you almost got away with it

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Re: rudder spacing?

Post by Larry » Mon Aug 15, 2011 11:15 pm

A light, flat bottom boat can like to slide. That pe60 isn't much weight to get the back of the hull to dig in and turn. My 125 deckover is almost as free as a stephull while turning, my brother calls it a drift boat.........

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Re: rudder spacing?

Post by dick2256 » Fri Aug 19, 2011 3:19 pm

DIXIENOURMOUS wrote:well first day out on my first boat and tried to make a turn and ended up in a tree. i was makin the turn at 2500 rpm's turned the rudders and it really didnt turn so i revved it to 3000 and it just made me get in the tree faster lol.the boat slid side ways in to the tree but i really had no control
the boat is a PE 60 aluminium hull with a 3 blade warp drive and the rudders are real close to the hub should i move them apart?
when I built my first boat years ago the guy that was my adviser said I should use water rudders along with the air but that was a bad idea it did turn nice but was hard to set it up so the rudders would flip up if you hit a rock or a log,I ran those about a month and took them off and just used the air. Just takes a little to get to know your boat.

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Re: rudder spacing?

Post by DIXIENOURMOUS » Sun Aug 21, 2011 10:20 pm

ok well i got found some skinny water and went wild tryin to find the boats limits my findings are that it takes alot of water over the deck and still floats, it will flip over if a wake rolls under you long ways,and when on plane it will not turn i think its too light and doesn't want to hook like larry suggested
believe me i tryed to wreck this boat to test the limits
is there a way to fix the not turning on plane?i am going to try to raise the back of the motor is this the right direction?
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Re: rudder spacing?

Post by JAMES » Sun Aug 21, 2011 10:25 pm

Smuggler wrote:Here is a Rudder spacing formula... Length of prop divided by 2 minus 10= rudder spacing.. That should put you right on the money :D
WHERE DOES THE MINUS 10 COME IN PLAY JUST WONDERING
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Re: rudder spacing?

Post by Smuggler » Mon Aug 22, 2011 7:12 am

JAMES wrote:
Smuggler wrote:Here is a Rudder spacing formula... Length of prop divided by 2 minus 10= rudder spacing.. That should put you right on the money :D
WHERE DOES THE MINUS 10 COME IN PLAY JUST WONDERING
Its just a formula I came up with and 10 seems to be the magic number. For me anyway :D :D

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Re: rudder spacing?

Post by cntry141iq » Tue Aug 23, 2011 12:46 pm

and the formula works ... just fine ... and if anyone is within an inch or two of being in accord with it they shouldn't just move the rudders to be perfect .. because it isn't that critical .. driver is much more critical LOL
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