Dave Frank plans ? Any good ?

[TERRY COWGER]

I think I will stick to the center with the drive and just offset the cowling.

Thanks T.C.

 

[Duck899]

Center the driveshaft I find works best. Most scales have offsets built in the sponsons that will help with torque issues anyway. Sometimes you need to add weight in or on the left sponson when viewed from the rear.

 

[lohring]

My electric Dave Frank hull has the motor and drive offset around 3/4" to the right. All the batteries are on the left to counter act the torque.

Lohring Miller

 

[TERRY COWGER]

Thanks for the reply, now I'm confused ?

I'm guessing it runs well as it looks well used, does it want to pull to one side?

Is this an 1/8 scale boat and does the strut mount in the center of transom or to the right, any sponson mods.?

Of course mine would be offset to the left and batteries on the right as it's going to a 1/10 scale and turn left.

T.C.

 

[lohring]

This picture is a good indication of how it flies out of a turn. Electrics have a lot of torque when they are generating more power than an 11 cc nitro engine at the same or lower rpm. The strut is off set as well as the drive line. This helps counteract prop walk. You can do the same thing by angling the strut.

Lohring Miller

 

[hugh hargett]

Cool photo! Thank goodness for a rudder with some length. Wat power you running in there Lohring?Shes coming off the water with great "Attitude" lol. Terry many run with no offset but running with offset can be an advantage or improvement depending on the hull and driver. Ive always felt a hull with it was likely a better turning hull or at least one capable of keeping a tighter turn towards its bias. I dont really like the angling of struts for this coz when youre in a straight line your fighting more drag even though the typical angle is very small. If you remember the "who makes this hull" thread with the bud hull. That was an extreme case of using strut angle to aid in turning or compensate for torque/walk issues. Either way sucess Has been had. The offset is more acuurate when building certain scales so I run it. I certainly dont think it hurts a boat when done right. The main thing is to figure out what your goal is when doing it. Prop walk,torque roll, or trying to keep the inside sponson down in a turn. All are different things in my mind things that somehow get melted together mistakenly when talking about offset, the reasons for having it, as well as on what side :unsure: .

 

[lohring]

That's a Tyler Garrard photo with Brian Buass driving. I learned about strut offset by looking at Joerg's 140 mph hydro. We had been using strut angle on our gas SAW hydros to get them to run straight. After that, I ran 1" offset on my next Laser mono, and Mike ran similar offset on his newest SAW hydros. I have no idea which method is best, but both work well.

I saw an article that suggested small strut angles aligned the resultant of prop walk force and prop thrust with the boat's centerline. However, we were starting to run strut angles of over 5 degrees and still needed some rudder angle to get the boat to run straight. Maybe a combination would be best. Also, prop walk can be reduced by more efficient propellers than the ones we were running in the beginning.

Lohring Miller

 

[TERRY COWGER]

Thanks for the help guy's

The thing is I don't know what issues I will have with this boat?

It's going to be run in the 1/10th Modern Scale class. I plan to offset the cowling to the left and I will be running a ,062 wire drive and P spec. power.

I have no problem offsetting the complete drive train, if it doesn't cause me problems or if it will work better ?

If offsetting would help it hug those pins, then I'm all for it ?

T.C.