Adjusting lateral trim

C

centerisland

New member
I've seen a number of mentions of "moving things around" to adjust lateral trim depending on load, conditions, etc.

Currently I'm adjusting the trim to level at rest using fuel - the water tank is dry for the winter, and since the boat is new to me there's very little equipment on board. And I'm going to relocate the batteries (as I just mentioned in another thread).

I have permatrims on the (2) BF40s, and no tabs (and would prefer to keep this configuration)

This is working OK since I've been mostly single-handing, but I'm wondering what techniques people use to dynamically adjust trim. I can see having a 5 gal plastic gas container in the cockpit and switching that side-to-side, but that will rob cockpit space (and does nothing to help trim the boat fore / aft). I could see having a couple of racks in the boat and moving lead downrigger balls between them.

So...what techniques do you guys use? Or do you just put up with a perpetual list like on the new WSF Chetzemoka (dubbed the "ILean" by wags)?
 
why are you not using the engine trim to adjust trim? if you have twins its very easy. I think that engine trim is under used by a lot of folks with out boards. My father in-law bought a 16 alum fishing boat with a 60hp on it for the lakes and rivers. Before we went fishing he complained about the lack of speed. When we hit the water I noticed he had the boat running bow down. He then turned to me and asked what I thought of the speed. I reached over and trimmed the motor up, got the bow out of the water and we picked up 10 mph at least. Ed looked around like a snake bite him. Coming from a world of older 2 stroke under 15 hp he had no idea about trim and how to use it. You should be playing with the motor trims separately to level out your boat.

I use mine to get on plane and then readjust for running. I never just set and forget them they are to much of a good tool for that.
 
starcrafttom":l3wufq7m said:
why are you not using the engine trim to adjust trim?
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I do that while running - but I have two issues with that as a "solution". First, the effect varies with speed - and does nothing at rest or idle. Second, I find that I'm running with the stb motor almost all the way down and trimming the port motor to approximate level, which doesn't give me any reserve trim capacity on the stb motor.

I'm probably going to address the second issue by moving the batteries forward, but I really would prefer to start out with a more neutral trim.
 
One word, PERMATRIM. Even on our single main, the difference in trim adjustment with the Permatrim as opposed to without it is significant. In fact, I use the Permatrim much more for trimming the bow than I do using the trim tabs. I think the Permatrim will give you a lot more room for adjustment because even the slightest trim adjustments make a big difference. I've heard of other C-Brats who have installed Permatrims on their twins so that may be the way to go. Just my $.02.

Peter
 
Jazzmanic":13ux75p9 said:
One word, PERMATRIM. Even on our single main, the difference in trim adjustment with the Permatrim as opposed to without it is significant. In fact, I use the Permatrim much more for trimming the bow than I do using the trim tabs. I think the Permatrim will give you a lot more room for adjustment because even the slightest trim adjustments make a big difference. I've heard of other C-Brats who have installed Permatrims on their twins so that may be the way to go. Just my $.02.

Peter
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Peter,

He has permatrims already and doesn't feel that's sufficient for his needs...
 
We use trim tabs on the move but I have packed the boat and outfitted it to meet my needs as well. We keep three, one gallon jugs of reserve fresh water on the boat and I keep it mainly in the anchor box to weight the bow but you could do something similar and keep them in a cabinet or two. I figure its cheap, heavy, useful, and easy to get rid of if you need to. Battery movements or additions can help of course. Have you considered adding more house bank capacity? Do you have anything else heavy or plan to purchase something else heavy for the boat?
 
C.I.
Tilting your motors up or down together will bring your bow up or down repectively. Side to side trim you need some movable ballast like a wife or girlfriend. There are other alternative lifestyles but I'm still in the don't as don't tell mode. :shock: We carry a cooler and a rolled up dinghy so we usually can move those items around and use the the fuel valve to pull fuel from what ever side tank we need to, to get leveled out. in the mean time the little woman hangs out where we need her to be. I don't have twins :D so I can't speak to what might happen if you trim one motor different than the other to effect side to side trim. I hope you get straightened up.
D.D.
 
rogerbum":2oimbu69 said:
Jazzmanic":2oimbu69 said:
One word, PERMATRIM. Even on our single main, the difference in trim adjustment with the Permatrim as opposed to without it is significant. In fact, I use the Permatrim much more for trimming the bow than I do using the trim tabs. I think the Permatrim will give you a lot more room for adjustment because even the slightest trim adjustments make a big difference. I've heard of other C-Brats who have installed Permatrims on their twins so that may be the way to go. Just my $.02.

Peter
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Peter,

He has permatrims already and doesn't feel that's sufficient for his needs...
Click to expand...

Oops sorry, I missed that. :oops:

Peter
 
Aurelia":b6wnowwg said:
We keep three, one gallon jugs of reserve fresh water on the boat and I keep it mainly in the anchor box to weight the bow but you could do something similar and keep them in a cabinet or two.
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Would 24 lbs really make a difference - and you with a 25'? Water jugs as movable ballast is indeed convenient for a variety of reasons but i figured you'd need 5 gal containers at the outboard edges to have any affect.

Aurelia":b6wnowwg said:
Have you considered adding more house bank capacity? Do you have anything else heavy or plan to purchase something else heavy for the boat?
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I am indeed wrestling with increasing baattery capacity - thinking of heading to Cabela's this afternoon to get their AGMs on sale. My biggest problem with more capacity is getting it charged - the BF40As only produce 10 amps each so when running - with electronics - I'm going to only have 10-15 amps to charge with. 2 group 27s, average capacity 95Ah each, combined, 50% discharge rule, is 95Ah - which would take at least 6 hours running to charge. <grin>

I do have an inflatable I'm going to put on top (centered), but beyond that the boat is primarily a commuter to our cabin so I don't have much additional equipment planned. Except now that you mention it, I do have a Yamaha 2.5 kicker - I could fashion a storage mount at several locations to move that around. Except it would obviously be in the cockpit (or on the stern) and could become a theft target. Have to think about that...

One more bow weight contribution would simply be some additional / larger chain, though it wouldn't easily relocatable.
 
Will-C":22kbqw1q said:
Side to side trim you need some movable ballast like a wife or girlfriend.
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Indeed - having my wife along does help balance the boat laterally, though please don't tell HER I said that!. Also, our 50lb dog has gone with me once and prefers to sit under the dinette - perfect location! So I guess I'm really looking for something when I'm solo - and I'm thinking that (4) 10lb downrigger balls would be quick to move around, not take up much space, and if I ever get around to fishing they could even prove useful. <grin>
 
It doesn't take much to make a difference, especially in motion. When my 33lb daughter moves around the boat (constantly) you will surely hear me clicking away on the trim controls. Maybe I'm just picky though.

I mount our little dinghy outboard on a cockpit rail for better balance and you could do something similar as well. That makes a big difference being so far from center. I keep a large cable and lock on it.

I have about 400AH on our boat and only 32 amps max from our outboards so I feel your pain. The real question is how long do you go before plugging it into shore power or a generator. I added the capacity for our needs but don't truely rely on the motors for a full recharge. I have a solar panel and generator for that and each time we are at the dock, I used shore power to top-off as well.

We also keep a cooler strategically placed and I have removed, moved, or added other equipment to keep the balance. If you all knew how my house batteries were positioned you would think I was crazy...(with what I have on the roof, many already do) but the 25 is a fairly weighty craft.
 
Aurelia":2sh0yq0a said:
I mount our little dinghy outboard on a cockpit rail for better balance and you could do something similar as well. That makes a big difference being so far from center. I keep a large cable and lock on it.
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Looks like my outboard with some fuel would be about 45lbs - so that would help.

Aurelia":2sh0yq0a said:
The real question is how long do you go before plugging it into shore power...
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I haven't nailed that yet - but I believe I'll be hooked up to a 15A outlet in the shed where I'm storing it. So, yes - I would normally be all topped up.
 
If you don't need it charged up fast at the dock, you might be able to get away with your existing charger provided you buy compatible batteries. I built one of these into the boat to do the majority of charging on my two big house bank batteries and it does a fantastic job with no moving parts.

http://soneil.com/12_volt.html

Model No. 1206S

It really does charge like a larger charger and I have confirmed low actual watts used. I have a portable 30amp smart charger if I am in a hurry.
 
We use a 5 gallon extra water container, ice chest, Dinghy motor, gear box (generator, power cords, etc) for lateral trim (athwartships). The fore and aft trim, would be by moving batteries or tanks forward etc.

There is a good reason that many folks have both trim tabs and Permatrims. The trim tabs work very well for both lateral and fore and aft trim. The outboard trim is to put the thrust of the outboards parallel to the water/plane of travel of the boat. If you are forced to put one engine down all of the way, it is not running at its most effecient angle. Also as you point out-there is no latitude to get the bow down further in chop. Although I did not have trim tabs on my 22, I had both trim tabs and Permatrim on the 25, and it made a huge difference.
 
I use those 2.5 gallon water jugs with the tap on them and a bunch of the small bottled water bottles under the floorboards to make up empty water tank in the winter or other mis-balanced conditions. You also have pots and pans, extra ropes, spare anchor/chain/rode, canned foods, and a whole host of movable weight items that could be stowed under a bunk or seat.

I think the goal of the boat sitting even at rest would be the ideal so you won't have to lose performance or safety by compensating techniques underway, as mentioned by Dr. Bob.

Once you find the right combination and position of items for a solo voyage vs. one with odd or even number of passengers, it will be easy.

John
 
drjohn71a":20et5klz said:
I think the goal of the boat sitting even at rest would be the ideal so you won't have to lose performance or safety by compensating techniques underway, as mentioned by Dr. Bob.
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Yes, that's my goal. I wouldn't mind the lateral trim compensation as much if it were not so speed-dependent. I can probably get used to it, but I'd like my wife to feel comfortable piloting the boat, and I have a vision of our kids using it as well. So reducing the number of simultaneous variables that must be balanced is my intention. Then, when you have something that truly needs your attention you're not so distracted.
 
Since I have a "settee" on the port side, with guests on board, I typically have more weight on that side. I compensate by monitoring my gas levels in the two tanks.

The Permatrims work well, but I have no adjustment fore and aft by trimming the motors, as (most of the time) I would like to lower the bow (not raise it) esp. when I have guests onboard. One year I put a 30# anchor in the the "anchor well" at the front of the V-berth. That worked well for fore and aft trim, but it was very difficult to get the anchor in and out!
 
Has anyone moved the 20 gallon water tank from the back of the dinette to the front. The storage space is virtually the same size and the hose penetrations could stay the same. Seems like an easy improvement. I have also been thinking about putting a bladder under the v-berth and doing away with the hard tank. I have the hatch covers, just waiting for better weather to go cut the openings.
 
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