Electric Trim System

[Fastjeff57]

I waited a year until I had this system perfected before posting it, if anyone wants to build one.

To wit: An electric Lenco trim tab cylinder (about a hundred bucks) rotates a cam that raises the tower about 3 pin holes. The obvious advantage of this system is light weight: the whole works is less than 3 pounds (and it’s all steel—Fastjeff wonder metal. Aluminum fabrication would trim some weight.) A DPDT momentary switch works the Lenco with two relays (one relay for + and one for -) to handle the amp load for Trim Out. With minimal load on the system during Trim In, the switch contacts alone handle the amps.

A ½ inch smooth rod is used for the camshaft, rotating in holes drilled through the clamp brackets (where that cross rod was bolted). A piece of 3/8 “ pipe with the cams welded to it is clamped to the ½ “ rod via two set screws in drilled holes. The cams push against an 1/8 “ pipe that rolls freely on the 5/16 “ rod that was used for the neutral/ reverse locking system. (To prevent bending of this rod, the cams are located to the extreme ends.)

After trying to mount the foot long Lenco cylinder to push directly on the arm of the camshaft, I instead made up a simple rocking arm to put it inside the boat instead. Not only is this a neater installation, the rocker arm allows adjustment for various strokes, which helps tailor the system.

That’s it. Nice and simple, fairly easy to make, lightweight, uses less than120 bucks in materials, and it works!

Fastjeff

[Steve Martin]

Neat set up! Compared to a stock trim unit, how fast does your setup trim out?
Forgive my ignorance, what is a DPDT momentary switch and what relays/setup
did you use? Thanks, Steve

[Fastjeff57]

DTDP = Double Throw Double Pole switch.

I used basic Bosch type relays I got off eBay for about 6 bucks each with the connectors.

I can publish my wiring diagram if you wish?

The system goes from full IN to full OUT in about 4 seconds.

Jeff

[Chairman]

Is the Lenco actuator strong enough to be used in place of a hydraulic cylinder on a "regular" trim system -- at least on a small (25hp - 40 hp) motor?

[Fastjeff57]

Neat setup! And it's totally immersible without damage, in case you're wondering.

Jeff

[Chairman]

So that's a yes? Strong enough to be used in a setup like this?

[Yellowjacket]

So that's a yes? Strong enough to be used in a setup like this?

I would think so, he's got it on a 4 cyl merc with a full length tower.

For use on something like on your Dillon you need to mount the outboard pivot for the cam shaft lever on the jacking plate. Not a big deal, but with the way it is set up on that boat you can't jack the motor up or down. I would think you may will want to do be able to change your motor height and he can't.

Overall, a very clever and low cost solution.

[Fastjeff57]

..."...you may will want to do be able to change your motor height and he can't."

Actually, I can (though I prefer not to--long story). The triangular black bracket can be relocated upward on the transom up to several inches, and the rocker arm push rod length modified or simply readjusted.

Jeff

[Yellowjacket]

Yea, you can, but as you said, it's not easy. You would have to loosen and move the bracket too. Then the linkage is going to be different and the trim gage might have to be adjusted too.

If the bracket is on the jacking plate it would move with the jacing plate and you might have to adjust the linkage, but it you would have to do that either way.

If you could figure out a way to mount the cylinder on the jacking plate it would go up and down with the motor and it would all stay aligned and working without hassles. I think that could be done pretty easily, and it could work really well.

When you are testing a rig, time is precious. You need to be able to make adjustments quickly and then get back on the water. If you have to fiddle with adjusting the system every time then it is not as useful. I think it's a good idea, but for what Dillon needs to do it needs some refinement.

[Fastjeff57]

Ah! See what you mean. I'll looking into what you suggested. Sounds like a fun challenge!

Jeff

[Chairman]

I got an email from one of my customers this morning. He has set up a trim system on his Dillon Mini Vee using a trim-tab actuator. He hasn't tested it on the water yet. I will update when I hear the results.

Brent's project: http://www.dillon-racing.com/customerboats/Compton/

[Yellowjacket]

I got an email from one of my customers this morning. He has set up a trim system on his Dillon Mini Vee using a trim-tab actuator. He hasn't tested it on the water yet. I will update when I hear the results.

Well if it does, he can count himself as lucky... Not say'n it can't, but its a poor design for several reasons.

First is that trim actuators don't have a lot of force capability and this is mounted in a way that diminishes that. That is, it is angled away from the line of action, and you have to push like crazy to get any force applied to the motor. If it was much straighter it would be more effective. As it is, most of the force is wasted. It will probably jack inward easily, but it's going to have to work like crazy to to move the motor out when you are running.

Second, it doesn't take a lot of travel to do the trimming. and mechaincal work is the force time the distance. Here you are minimizing the amount of travel, so it takes a lot more force to do the work. Using some type of lever assy (as the OP did) lets the cylinder travel more and allows you to gain force through the mechaincal advantage.

With this short a travel it's going to be very touchy to find the correct trim position, if it works at all.

Like I said, it might work, but it also may overload the actuator, and stall it, or it could just break the plastic end links on the actuator. Thost things just aren't designed to be used like this, if you want this kind of installation, get a real trim cylinder that can make big forces and go for it.

[Chairman]

Brent tested his system and reports that it "worked great!" He says he achieved 50 mph with a 30/35 OMC on his Dillon Mini Vee.

http://www.dillon-racing.com/customerboats/Compton/

[Fastjeff57]

Way to go, Brent! Tested mine yesterday and, though I had a ton of other problems, mine worked great as well.

Jeff

[Steve Martin]

Jeff, could you email the wiring diagram and any pictures for the relay setup?
martin_spm@hotmail.com
Thanks, Steve

[Fastjeff57]

Here you go. I used the switch alone for retracting since it's low load, but two relays (one for each wire + and -) for extend.

Jeff