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Author Topic: problems !  (Read 1448 times)

triumphjon

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problems !
« on: September 22, 2011, 10:06:36 PM »

ive almost completed the restoration / conversion of a circa 1920s pond yacht into a radio controlled yacht , however its maiden sail yesterday didnt go too well ,  its unresponsive to any helm inputs and seems to prefer sailing backwards instead of forwards ! !

its 45 1/2 inches loa including a ten inch bowsprit and five feet tall from its keel to the tip of the mast
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Jpop Andrew

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Re: problems !
« Reply #1 on: September 22, 2011, 10:25:38 PM »

I can't quite tell from the picture, but one thing to consider is how large your rudder is.  With square riggers anyway a four foot model would need a rudder about four times larger than the original ship's proportions.  On my HMS Beagle I found that a rudder only three times larger than the original wasn't large enough, and had to add a Plexiglas extension.
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triumphjon

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Re: problems !
« Reply #2 on: September 22, 2011, 11:11:52 PM »

a new rudder has been fabricated this evening , 4 inches x 7 inches high , im unable to make it any taller as it sits between the keel and the underside of the transom !
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tigertiger

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Re: problems !
« Reply #3 on: September 23, 2011, 05:35:04 AM »

One thought did strike me.

Sail set up. If the sails do not go out in proportion to each other, the jib can act like a weather vane. I have had this on a model where the jib jammed. She just faced upwind, would not turn and ended up going backwards.

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rmaddock

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Re: problems !
« Reply #4 on: September 23, 2011, 03:52:48 PM »

One thought did strike me.

Sail set up. If the sails do not go out in proportion to each other, the jib can act like a weather vane. I have had this on a model where the jib jammed. She just faced upwind, would not turn and ended up going backwards.


I'd actually had the opposite thought.  You've a very long bowsprit there with no sail flying from the very front. With a foresail, the centre of effort of the rig would move forwards. It's currently back which would also affect your steering but in the opposite manner to that suggested by Tigger above.  If the original model had a foresail then it may be balanced for that setup.
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Netleyned

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Re: problems !
« Reply #5 on: September 23, 2011, 05:14:13 PM »

No point in a bowsprit (pun intended)
if you don't have a foresail rigged on it

If the original set up was for pond sailing
back and forth it would need the balance of an
extra jib to keep it on line.

Ned
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rmaddock

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Re: problems !
« Reply #6 on: September 23, 2011, 05:25:40 PM »

Indeed  {-)
The absence would give it whatever the opposite of weather-helm might be. In other words, it would try to turn out of the wind. This, with the small rudder, might well make it difficult to control and lead to its seemingly wanting to go backwards. An alternative to a foresail would be to step the mast further forwards but that doesn't look like an option.  How about taking a reef in the mail sail? Less area there would move the CoE forwards.
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triumphjon

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Re: problems !
« Reply #7 on: September 23, 2011, 09:43:16 PM »

the bowsprit is indeed for a second sail to be added , its been cut but hasnt yet been stitched ! ( sewing machine belongs to my partner )  currently the sails are on independant control , ? with the bigger rudder installed ive managed to regain control of my steering
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