Rudders or should I say not using rudders

[ris]

We had a short discussion about taking off the rudders a while back. My question is "Is your Mac kind of squirrely when you are running about 6.5 to 7.5 mph?" We let the rope for the swing keel down about 6 inches when we are moving or docking only taking it up when anchored or docked. Would our boat move straighter with the rudders? (we have no sail) We have no problem docking without rudders. Today we had at least a 12 mph wind and had no problem docking. I do not know if it is the 14 inch prop or what it is but we come in slow, and if reverse the boat it stops almost instantly. Our only problem is keeping the boat straight when traveling. We have yet to get our auto pilot to work correctly. We were told by Ray marine that we needed to get some software update to make the wheel pilot work better. I am not sure if a update will do it or if it needs the rudders. You folks with newer Ray marine wheel pilots and no rudder sensors let me know how your boat does when running on the motor.
When we run 11 or 12 mph we have no steering problems but it is quieter and less stressful to run at 6.5 and 2000 rpms also uses a lot less gas.

[DaveC426913]

The general, widely and strongly held belief among Mac owners is:
When motoring
below 5 knots, blades down.
Above 5 knots blades up.

Motoring above 5 knots with a rudder or keel down is a recipe for leaving a good portion of it at the bottom of the lake.

[yukonbob]

Dave summed it up pretty good. Unless we're trolling and need the extra low speed control or while docking, if the motors on all the blades are up (cause we'd better being doing at least 7knts. Have no issues with control other than having to keeps your hands on the wheel at all times or the boat will veer off (right I think) no worse than any other boat I've owned tiller or wheel. It's not something that has to be fought just not completely ignored. If you're fighting it check your trim tab above the prop on the lower leg, just loosen and click over a few notches in the opposite direction it's pulling. Maybe swinging that larger prop is causing more prop walk? Maybe more so at intermediate speeds?

[Ixneigh]

I pick everything up under power at any speed. The M was so squirrly I added a set of skegs. These solved the problem.
Barring that check weight distribution. If the boat is heavy in the bow she's not going to power well at low speed.
Ix

[bobbob]

There's a lot of discussion here about the Mac "semi-planing" speed and how it can definitely be unstable. 7kts sounds low to be in that region (more like 10 kts) but who knows. As soon as you are trying to go above hull speed you should make sure to get comfortably into planing.

[Seapup]

Ray marine wheel pilots and no rudder sensors let me know how your boat does when running on the motor.

I had an old raymarine/autohelm on my There is no way it could keep the boat straight with no rudder. It was constantly correcting right or left and really only worked well when things were balanced. The new ones are probably much better.

I found no centerboard and one rudder to be the best hull speed motoring configuration on my

I noticed in the narrow canals like the dismal where you are going straight for miles adding any centerboard would make it track one direction or the other, especially when people moved around on the boat. It gets a bit boring and I would try all the configurations. A tiny degree off course and you are hitting the bank.

With the centerboard up and 1 rudder down it was not so sensitive and would motor along all day in a straight line flat water.
95% of the time flat water motoring I didn't even turn the autopilot on since it had a wheel lock. I just locked the wheel and let it track straight, no listening to the AP hunt around just to keep a straight line the boat does anyway when balanced.

[133bhp]

I leave one or both down when motoring, up to 14knts, been fine. I did use to bring them up, but you get that noted instability at around 8nts, Unless doing high speed turns, I don't think it matters, just a bit of safety margin by Roger I suspect?

[ris]

Ixneigh what and how did you add skeggs to the boat. Is it possible to have too much weight in the aft end of the boat? Maybe we will solve this problem. Great discussion

[Gypsea Wind]

Ixneigh, how and where did you mount the skegs? Pics? Thanks!

[WASP18]

Rudders and center board up while cruising at 5 kts, my X wants to zig-zag. Steering a straight course is a physical challenge.

Rudders down and center board down about one foot, the boat tracks in a straight line at 5 kts and it suddenly becomes a relaxing pleasure.

Same configuration when docking with rudders and CB down. So far, I've had good luck docking by playing the wind; low speed in forward gear, shift to neutral, let the boat coast, reverse throttle quickly, then neutral and the boat drifts in nicely. With the rudders and CB down, the boat doesn't slide left or right caused by wind.

[DaveC426913]

Rudders and center board up while cruising at 5 kts, my X wants to zig-zag. Steering a straight course is a physical challenge.

Rudders down and center board down about one foot, the boat tracks in a straight line at 5 kts and it suddenly becomes a relaxing pleasure.

With my above 7knots, it is a constant struggle to keep it straight. And even then, it's more of a straight-ish. I've tried CB up and down and everywhere in between.

I do not relish the thought of what is going through the minds of the skippers in oncoming vessels, when they see me slaloming like a skier. "OK, he's veering off to port. Wait, he's coming back. He's veering off to starboard. Wait, he's coming back. Get off the road idiot!!"

I would welcome suggestions.
But
1] don't want to add skegs, as that'll cause drag when sailing (or are they attached to the kicker?)
2] trim tab isn't the issue, as it veers either way equally.

Maybe my rudders are out-of-true...

I wish someone would run a 'Optimizing Your Mac' workshop.

[sailboatmike]

Mine zig zags but I have found its more operator error, so its not the boat its me.

The helm on my X is VERY direct so a small input brings about big changes in direction, I have learnt make a small movement of the helm and wait for her to come around, a heavy hand or come to think of it a moderate hand will result in the GPS plot looking like a zig zag stitch on a sewing machine

[WASP18]

Rudders and center board up while cruising at 5 kts, my X wants to zig-zag. Steering a straight course is a physical challenge.

Rudders down and center board down about one foot, the boat tracks in a straight line at 5 kts and it suddenly becomes a relaxing pleasure.

With my above 7knots, it is a constant struggle to keep it straight. And even then, it's more of a straight-ish. I've tried CB up and down and everywhere in between.

I do not relish the thought of what is going through the minds of the skippers in oncoming vessels, when they see me slaloming like a skier. "OK, he's veering off to port. Wait, he's coming back. He's veering off to starboard. Wait, he's coming back. Get off the road idiot!!"

I would welcome suggestions.
But
1] don't want to add skegs, as that'll cause drag when sailing (or are they attached to the kicker?)
2] trim tab isn't the issue, as it veers either way equally.

Maybe my rudders are out-of-true...

I wish someone would run a 'Optimizing Your Mac' workshop.

My personal experience is anything above five knots the boat will zig-zag in the configuration I described. At or below five knots the boat is rock steady. At WOT with rudders and center board full-up, the boat tracks steadily, straight ahead, with no bad habits. Therefore, between five and below fifteen knots, the boat is unsteady and needs to be constantly corrected.

These handling characteristics seem to be the majority-experience based on what I've been reading on these forums.

[dlandersson]

I just assumed it was my lousy seamanship - you know, like the commercial with the wife saying how her hubby is a lousy golfer.

My personal experience is anything above five knots the boat will zig-zag in the configuration I described. At or below five knots the boat is rock steady. At WOT with rudders and center board full-up, the boat tracks steadily, straight ahead, with no bad habits. Therefore, between five and below fifteen knots, the boat is unsteady and needs to be constantly corrected.

These handling characteristics seem to be the majority-experience based on what I've been reading on these forums.

[Obelix]

When motoring the at or below 6.5mph, I leave about 1 foot of daggerboard and the rudders down. This may use a little more gas, but the boat is very steady in this configuration.

Obelix