emmamarko112
26.04.2021 1:17:39
It looks like the last time this topic was brought up in this forum was in 2006. As a boating Newbie, I'd like to check with you experts to determine the preferred rotation scheme for boats.
See full version: Twin Motors and Prop Rotation
It looks like the last time this topic was brought up in this forum was in 2006. As a boating Newbie, I'd like to check with you experts to determine the preferred rotation scheme for boats.
For airplanes, the normal rotation is port engine rotates clockwise and starboard engine rotates counter clockwise. For planes, the convention is to view the rotation from the front of the plane. The theory for these rotation conventions is to use engine torque and prop blast to help stabilize a plane when one engine fails. more
As I understand boating conventions, the view is from the stern looking toward the bow. I think the prop rotation for boats has more to do with stability in hard turns, directional stability in reverse, and in stern movement during docking manuevers. [links]
When twin props/motors are set up correctly they can assist with steering. more
My reason for asking is that i'm currently building a Brede class RNLI lifeboat, and it should have twin props but ive only built it with one center mounted prop, this is because i didn't know the answer to the above question as ive never built a twin prop boat before, so sooner than take a chance which might prove costly i opted for the single prop.
Usually the port side prop rotates anti clockwise with a left hand prop, and the starboard side prop rotates in a clockwise direction with a right hand prop for forward motion. here
My thinking is that if twin props rotating in the same direction DON'T affect the steering then i might just alter the boat to twin prop, and power it off one motor, i know this would be awkward but it's possible for me to do.
I also found that I can get 39 with just an one more click of up trim but at that point the boat begins to lean left and gets hard to steer to the right. more
I have a 17ft riveted bass boat with a 50hp outboard and a brand new SS prop. No Tach, No Spedo.
So, I go home thinking I will adjust the torque tab on the outboard to the left (counter clock wise) to make the motor want to steer to the right and here is what I found. here
I took my GPS with me and found my top speed is now 38 mph which is up from 34 with the aluminum prop.
Just to catch out the unwary - unlike NEMA, IEC 60034-8 specifies that the rotation direction is viewed at the "D-end" i.e. the drive end (and so does BS 4999 Pt.108). [links]
CW or CCW The real meaning of these labels is dependent on the manufacturer.
ECCW Either clockwise or counterclockwise, connected for counterclockwise rotation at factory
CWLE Clockwise from the lead end [links]
So it sounds like if you say nothing, that's what you get. If you want different then tell 'em.
CW Rotation Only Shaft can only rotate in a clockwise position here