Twin outboard install, Fine design 32.

[RaisedByWolves]

That mount/pivot plate looks great. Nice job. I love the ingenuity. Adjustable trim for rough water is an awesome idea. I have always wanted to do a F1 tunnel hull with trim.

Madprops, I would think a rock crawler servo with 400+ oz/in May be enough. Or maybe a Retract servo? Be a slower speed too.

I have a bit of experience with the stronger servos and adequate power has to be supplied as they can have over 5amps stall.

Man, an F1 with tilt and mixing giving you precise down thrust on the bow in turns........

You could also add a gyro to prevent blow overs.


Mad, Im probably going to make a mount for inside the transom to hold the actuator. I can bolt it to the transom to transfer the motor thrust to the transom. This will have a pin going through the transom to take the thrust and be sealed with O rings or even a small boot.

Im pretty sure a mount attached only to the bottom of the hull will get ripped off as the actuator will be taking a large percentage of the forces put on the back of the boat from the motors.

I plan on using an intermediary link between the actuator and the thrust pin, but until I get it back and test it some more Im not sure if it will be under driven or over driven. That will depend on what amount of resolution I can get with the unit.

Then again it could always wind up as a direct link to the thrust pin.

Figuring it all out along the way is half the fun.

[MadProps]

as I mentioned this is my first scratch build and I have never run twin motors and I have no idea how other are controlling trim I was going to use a speed limiter to slow down a servo but I was mocking up parts today and came up with a tilt & trim system, since we only require a couple millimeters trim adjustment this approach may just work for me???? we will see

[JestDanny]

I would think with active trim you would need stops on each the up an down trim adjustments. The smaller the boat the smaller / narrower the window of adjustment needed? Most of my RC boating experience is with tunnels, I club raced 3.5 cc and 7.5cc nitro tunnels in years gone by, and have been messing with FE tunnels for two years. Too much head ache not enough gain IMHO. The window between too wet an too light is very small, with the wide sweeping turns of a typical race coarse you don't need a lot of boat in the water to make the turn. That being said, I do think as the hull size increases so does the adjustment window needed between full tilt up and down. Only larger hulls would benefit more me thinks. I don't know? Jest thinkin?

[srislash]

Agreed

[MadProps]

maybe I am missing something or dont understand your meaning but I only need less than 1/4" of liner travel to actively trim these motors & I can do it "incrementally & very slowly" there are stop points for the active trim adjustment.... using the 3rd channel mico trim adjustment I can bump it in to any angle I choose just like you can adjust in your rudder trim incrementally in a boat or plane to go straight

the tilt will go just full up and full down without in between stops , but the trim I can incrementally bump on the fly in to any trim angle I choose "within my range of travel" and at a super slow speed, maybe you didnt see the slow incremental adjustment of the servo arm in the video?

[JestDanny]

On our little race boats 1/4" is a huge swing in adjustments. When I set up and dial in a hull I'm only adjusting my tilt/ thrust angle by 1/64" at a time. On my little Dumas HS Sprint the window of thrust angle needed to trim it out is about 3/32". From the sweet spot where my boat is set up and runs and handles the absolute best, if I add 1/32" positive (up) thrust angle, I get a very light loose running boat with handling issues and am more likely to blow it off the pond. If I change the thrust angle down / negative 1/32" from the sweet spot I get a wet, plowing boat that looses 2 mph top speed. I honestly hope that active trim works out for ya. I jest think once the boat is dialed in proper you no longer need to adjust anything. I guess the only advantage is in the speed in witch a hull is dialed in you can do it on the fly, I have to loosen screws on the bench to make adjustments. Once on the pond I see no advantage over a well trimmed / set up boat. IMHO it jest adds complexity an head ache, being that the window of adjustments need is so small. Honestly good luck, keep us posted on your results, maybe I'm just an old fashioned fool set in his ways and totality wrong on this.

[MadProps]

well that clears things up Im not confused about your meaning you dont understand my approach to the concept & since its jest your opinion..... trim is not needed???? or it may not work! or too much work,a headache? then Im really not interested in your opinion if there will be a benefit ...........I already have benefited from the project

have you built a tilt trim system doesnt sound like you have .....your just wasting my time.....this 1/4 inch and the speed of movement your confused about tells me..... I personally dont think you have the mechanical aptitude to understand my approach to the concept. did it cross your mind YOU may learn something from our efforts? this is pretty simple stuff here gents and not uncharted waters, others that possess mechanical aptitude skills have installed trim and it worked well!

what makes you think were are not capable of slowing them down enough to accomplish this ...hear of servo speed controllers....you dont think there is any application benefit for this? changing water conditions that I will be able to adjust on the fly, you say you need to bring your boat back and adjust 2 screws to do this? well I will only press a button on the fly and achieve the same benefit as from a real boat....... try thinking outside the box

too much headache! too much complexity maybe this conversation is above your skill level, let alone injecting your uninformed opinions, we will successfully engineer trim systems.

I already know there will be a benefit and frankly it really dosent mean diddly if this turned out as useful as interior lites in a tug boat ....then Im just damned thrilled, Im doing this because I possess the skills to accomplish this engineering mod.............. because Im a modeler


edit: people are already racing with working on the fly trim on F1 hydros.... and using just a servo....since your so free with your uninformed opinions let me give you mine..... next time you go to post "I think" stop yourself and go google the subject before you waste peoples time, jest a 2 second look I found some already racing F1 with trim, there are boats on youtube with nice slow incremental trim .some boats come from the factory with trim!!!...yeah were all wrong but you

this excerpt taken from RC groups
there is a racer in Texas, Ernie LeFleur that runs trim on his 3.5 OB tunnel.Ernie's works rather well, he can hold the engine and it will move the rest of the boat with no problem.

you have a great day I have a technical project to finish and dont have the time to explain how it works
but thanks!

[RaisedByWolves]

The only downside I can see is weight, but with twin engines......


The length between the pivot and the locking bolt will make a given measurement of tilt (Which should be spoken of in degrees) will be different for different mounting systems. .015 of adjustment for one setup may be minuscule while for another it is huge. Hence the need to use degrees for any of this to have any meaning.

My biggest concern is having too fine a resolution where it takes a lot of input to achieve the desired result. On some radios the amount of throw for a given input can be changed to account for proper function which I can utilize on my Graupner MX24.

Unfortunately that is not the radio I will be using for this boat.


Mad Props your setup looks nice. Interested in seeing it on the water. You're going to need a pretty stiff rod on the tilt/trim servo. Have you given thought to how your steering links will handle the tilt?

That is currently one of my biggest challenges along as well as how it will work regarding the jack plate, but the jack plate issue will be a one time setup.

[RaisedByWolves]

Well my build got stalled as I had to send my actuator back to the manufacturer in Canada to get it reprogrammed to work like I want it to.

Heres the issue I was having.

[zooma]

Not so linear, eh?

[RaisedByWolves]

Not so linear, eh?

Got an email saying they were able to write new code and flash it to work the way I want it too. I should have it back in a week or so to test.

Got the mount done and the motors temporarily mounted for fit and everything looks good.

Also showing my patented wine crate boat stand/storage box. Still needs foam but this lets me put boat/radio/batteries and tools all in one tote.

[RaisedByWolves]

So I have been putting this off to work on my 1:1 boat to eventually do some fishing but Im now getting back to it. I got my actuator back and they reprogrammed it and thats working well. I also milled the forward mount for the actuator and got it light enough that I think it is done. It came out looking like a cross between a Tie fighter and an X wing with all of the angles and extra material removed. Pics coming soon.


My dilemma now is how to go about creating a steering system that wont interfere with the trim/tilt, or better said, wont deviate the steering inputs when the motors are trimmed. I know I want a push/pull operation with the motors linked via an adjustable linkage Im just not sure how to go about it.

Can anyone give me some insight into the workings of the twin steerable outdrive setups that look to have some type of piston (Hydraulic?) steering setup?


Something like what is being used here.

https://forums.offshoreelectrics.com...5&d=1518063460

[properchopper]

Cool project You probably know about these guys but if not there may be some product/ideas that could fit with what you're trying to accomplish...

https://www.servocity.com/

[srislash]

Well this ( https://forums.offshoreelectrics.com...5&d=1518063460 ) would be me. These hydraulic dummies can be bought by themselves and come in a couple lengths. They can/or may have flex cable glued into them. Positioning for smooth operation is key, depending on application (the one pictured being about as tuff as it gets). Now I have also thought of making my own using .098 prop stubs and cable in brass tube. Having steerable drives means you don’t need a lot of rudder throw either. I do have a functioning one here if you need measur.

Shawn

[RaisedByWolves]

Cool project You probably know about these guys but if not there may be some product/ideas that could fit with what you're trying to accomplish...

https://www.servocity.com/

Thanks, I forgot about them.

They have some interesting ball links I may have to get.