power trim

[jken1995]

Just curious if a servo could be used for power trim for a 3.5cc size engine. If so how much torque would be necessary to do this. If not has anybody been succesful with setting up a power trim system of another type?

Jeff

 

[Mark Poole ModVP]

Yes it can be done but you will see few racers use it. I think that it would take a pretty stout servo. The one to ask would be Ernie Lafluer. He uses trim on his boat and obviously it works very well for him.

 

[Jerry Wyss]

Mike Hughes has done that,, frustrated him as I remember,, In a race .

JW

 

[SayMikey]

Mike Hughes has done that,, frustrated him as I rememberJW

I talked to Ernie after a ball buster run at the Nats time trials. I said whats all that salad for. He said we threw the boat in the water Trimmed up, got the needle,slipped the pipe in and made a bonzi run all after setting everything in the back straight. Any man that can do all that in one pass is a REAL MAN not me id be confused and HIT something......

 

[10x8]

Just curious if a servo could be used for power trim for a 3.5cc size engine. If so how much torque would be necessary to do this. If not has anybody been succesful with setting up a power trim system of another type?
Jeff

Page 662 of the Graupner Modellbau 2003. You could apply this to nitro setup if you wanted too I'm sure. I think any hi-torque 12kg job servo would do the trick.

Peter

 

[jken1995]

This boat is not really for racing(fun boat). I have always wanted to try this on a dumas tunnel I have just to have a little fun with it. I think I have seen Ernie on this site before. I will have to check the member list.

Jeff

 

[jken1995]

I need to thank Peter for the attachment he sent. I will have to study that some more.

Thanks

Jeff

 

[waltr]

The Graupner setup won't work on our boats.

I see a bunch of things torn up. I really doubt you can control the trim with the steering rods anyway. I have a few 67 and 80 OBs where a small geared electric motor turning a screw attached to the OB motor works the trim,but the setup is heavy.

Ernie's setup is with a cam and works pretty slick.

The man knows his OBs and he runs 5 channels. I struggle with 3

https://www.intlwaters.com/gallery/displayimage...m=917&pos=9

 

[moparbarn]

k&b made a power trim setup WAAAAY back when. they will pop up on ebay every now and then. don't have a clue about servos needed.

 

[waltr]

Another setup is on my AMPs OB with K&B 11.

It uses a servo,lever and a rod, but it really doesen't work all that well either.

 

[HTV Boats]

Just curious if a servo could be used for power trim for a 3.5cc size engine. If so how much torque would be necessary to do this. If not has anybody been succesful with setting up a power trim system of another type?
Jeff

Jeff,

To answer your question, on my 7.5 tunnels I use a Futaba 3305 (100-124 oz) servo and it works fine. Has metal gears which are a must. Remeber you only need to move your lower about an 1/8th of an inch at the bottom of the mount. I have made direct leverage mounts and like the one I got from Ernie LaFluer the best. Uses a cam which takes constant pressure off that a direct leverage would have. Ernie uses a stick radio and drives with total trim control. Very few people are that good with a radio so I just use my 3rd channel as a switch with down and up trim preset. Gives me choice of a conservative or blow over ragged edge boat with the touch of a button. Ideal would be to pull the trim out of the corners and let it down about 3/4 down the straight setting you into the turn. Again in traffic I am not capable of doing this all the time. If I get behind it gives me a boost but I find I drive the conservative side more often for faster laps. We used to set up fixed on the ragged edge and throttle back. Now I seem to be able to barrel through corners without lifting. If your off on the needle it also may break loose a stiffer prop. Trim gives me a choice.

Mic

 

[jken1995]

Mic

I can pretty much picture what you are talking about with the cam and I can see the benefit for using a cam with the constant pressure of the motor running. Is there any pics though just to make sure I understand this setup? It may be a handful but it has got to be fun driving it!

Thanks,

Jeff

 

[Tim_Duggan]

pic in gallery

 

[HTV Boats]

Mic
I can pretty much picture what you are talking about with the cam and I can see the benefit for using a cam with the constant pressure of the motor running. Is there any pics though just to make sure I understand this setup? It may be a handful but it has got to be fun driving it!

Thanks,

Jeff

Jeff,

Look in my photo albums under HTV Boats I put a couple pics of Ernies trim. Couldn't figure out how to put one here. Cam rides in an oval slot in the swivel block. Take a piece of mayby 3/8 inch round stock and drill an offset hole for a shaft to turn it or just take a wheel collar that is for a larger shaft and set screw it to the smaller shaft and you have a cam.

To the contrary the trim takes a setup that can be a handful and gives you control. The fun is having the "button" for 3-5 xtra mph.

Mic

 

[jken1995]

Mic,

I am glad you had those pics as what I was picturing was not even close. Ernie L. setup is pretty slick and after seeing the pictures I can see why it works so well. Simple and easy! Thanks alot for all the help.

Jeff

 

[Mike Hughes]

My set up was for an 12cell electric tunnel back in the early 90's. I used a high torq futaba. I think it had 140oz. I used a cable attached to the bottom of the mount to push it in or out. The top was the hinge. I had wired an extra trim pot into the radio. All I had to do was push a button and it would change the ohms on the 3rd channel and move the servo. As soon as I let go it would go back. By using a trim pot I was able to change how much the mount moved when the button was pushed. Worked great. The electric boat was really light and it would fly down the shute and I was able to set it in the turns with the button. I never really tried it on my nitro boats. The LYNX. tunnels I run now do not need anything like that to get through the corner.

Mike

 

[jken1995]

Mike,

Your power trim setup sounds cool. Especially the fact that you had to wire the radio itself. The great thing about this hobby is that any one person is only limited by their own imagination.

Jeff

 

[Joe_Knesek]

A linear actuator like this may be worth looking into.

 

[jken1995]

It looks like that linear actuator plugs into a receiver. I have never seen one in rc use or in any catalog. Where can you get these and are there any other types of actuators for rc use?

Jeff

 

[Propualsion]

It looks like that linear actuator plugs into a receiver. I have never seen one in rc use or in any catalog. Where can you get these and are there any other types of actuators for rc use?
Jeff

Hi,

yup, same here... Joe where did you get it? Appreciate your reply. Thank you.