Singles versus Twins

Grumpy · Posted: Fri Mar 23, 2012 11:01 am Post subject:

Charlie,

As payment for my past sins, many of "my" products are incorporated in brand new airplanes which take off, make a left turn, and fly over my house many times per day Shocked

Don't start me on my favourite soapbox, it runs through several bottles of wine.

But, if your car or boat had the same despatch reliability as a modern airplane, you would sell it quickly.

Cheers,

Merv

Larry H · Posted: Fri Mar 23, 2012 1:05 pm Post subject:

hardee · Posted: Fri Mar 23, 2012 1:30 pm Post subject:

Chester · Posted: Fri Mar 23, 2012 1:48 pm Post subject:

Harvey, a quick question. How much toe in do you run on your outboards?

ferret30 · Posted: Fri Mar 23, 2012 4:23 pm Post subject:

I'd skip the Teleflex system and go straight to a Voith Schneider Propeller:

http://en.wikipedia.org/wiki/Voith_Schneider_Propeller

They make them for large ships and tugs, and there's a tiny version for RC models, so we just need something in between! Smile

Of course, the draft wouldn't be 8 inches anymore...

hardee · Posted: Fri Mar 23, 2012 4:27 pm Post subject:

I do know there is such a thing, but I don't know how much mine are set at. In talking with my mechanic, if I remember right, because the twins are very close together comparatively, I don't recall that "toe in" would make any difference.

I'm open to learning more on it. Affect on vessel, with and without, and anything else important, I guess.

Harvey
SleepyC Moon

Dora~Jean · Posted: Fri Mar 23, 2012 4:47 pm Post subject:

I have twin 80's on my CD25, the toe-in is set for 3/16" at the front steering bar that joins the two motors. That is the number I was given when I took delivery of the boat, and have kept it there (repaired the slave steering cylinder once, requiring removal). Not sure how critical this is or even if it affects the operation/steering.

rogerbum · Posted: Fri Mar 23, 2012 4:55 pm Post subject:

Chester · Posted: Fri Mar 23, 2012 4:58 pm Post subject:

My boat came with 1/4" toe out, measured at the nose cones and propeller shafts. It was difficult to maintain course at that setting. After changing it to 3/16" toe in it handles much, much better. Thing is, I haven't tried fine tuning it and it is possible there is a better setting.

Captains Cat · Posted: Fri Mar 23, 2012 5:10 pm Post subject:

Pretty hard to measure on a TC255. We have a "liquid tie bar" which allows an almost infinite toe in toe out setting. Our engines are VERY far apart compared with a usual twins setup.

Come to think of it, maybe control of that connection could do a partial Optimus 360 trick!!

thataway · Posted: Fri Mar 23, 2012 7:05 pm Post subject:

Two words--Lightning Strike--either direct, or nearby in the water. All systems are out! I see it happen frequently down here in Florida.

I know of one at least one large Nordhavn which was totally disabled by systems electronic failure. (There is suspicion that a second one also had this and was the cause of its loss). These are very high end yachts which cost millions of dollars, and should have back up systems.

lloyds · Posted: Sat Mar 24, 2012 12:25 pm Post subject:

This is the first time I have noticed a discussion on "toe-in" for twins. I have never been happy with the steering on my 22, it bears to starboard. I changed the tabs on the engine and it helped but still not correct. Does anyone know the correct toe-in for twin honda 35's, 40's, or 50's?

Chester · Posted: Sat Mar 24, 2012 2:32 pm Post subject:

Captains Cat · Posted: Sat Mar 24, 2012 2:40 pm Post subject:

Chester, according to his profile, he has twin 35's.

Maybe the port one got switched with a 45 and just LOOKS like a 35??

Shocked

Charlie

thataway · Posted: Sat Mar 24, 2012 6:47 pm Post subject:

The other issue can be that you have two right hand motors--which is quite likely. You may need more trim tab correction.