1/4" Dual Rudder for 51" FE

[jlanders001]

Hi guys. I’m building a 51” FE boat for the first time and I have a few questions if any of you have the time.

What are the pros and cons of a double rudder for a 51” FE with ¼ flex shaft vs. a single rudder? What do you guys think of this one:

http://www.ebay.com/itm/130419150856...84.m1438.l2649


What prop(s) would be good for a 51” FE? Would a X457/3 work for a good balance of acceleration and top speed?

Thanks,

JTL

[jlanders001]

Can nobody help me on these? I would really appreciate it if you could.

I even have more questions now:

Can you have too much servo power? I have a 1/4 scale servo that puts out 349 oz/sq in. How much power would be good for a double rudder 51” FE?

Where do I get a motor mount for a CC 2028? What about Collet too for the 2028?

Thanks guys!

JTL

[srislash]

I'm pretty sure you can get any mount for any hull here http://forums.offshoreelectrics.com/...01-motor-mount
I don't think you can have too much servo power,I had the same question awhile back and everyone seemed to be using a 125 oz/in servo for single setups.I had found one with big specs 300+oz/in but it was a retract servo for a plane and waayyy too slow.Thats what I would watch for.And depending how fast you want to go,maybe a metal gear servo.If you stuff the boat backwards its alot of pressure on the servo.
And lastly,OSE here should have a .250 to 8mm collet.http://www.offshoreelectrics.com/pro...oct-ocfhe8mm25
I do however see they are out. Ah,found one http://kintecracing.com/Collets_Couplers.html

[Doby]

What 51" hull are we talking about??

[jlanders001]

This one:

http://www.ebay.com/itm/300630788645...84.m1497.l2649

I liked the lines of this boat a lot. The guy who builds them is very talented man. Very very nice too.

[LarrysDrifter]

Looks like giant pain to tape.

[JIM MARCUM]

Two rudders may look cool, but have twice the drag. I'd go with a single offset rudder & a 1/4" twin needle bearing stinger drive. JIM

[Make-a-Wake]

Here's my 51" GT...........same one................it did a sub impression on the fifth run..........

You need to re-inforce the hull very well if you are going for the speeds i went for.

[jlanders001]

Here's my 51" GT...........same one................it did a sub impression on the fifth run..........

You need to re-inforce the hull very well if you are going for the speeds i went for.

Thats cool man. I'd love to take a look at some pics of your transom and interior for layout ideas. If its not to much trouble send any pics you may have to jlanders001@sc.rr.com.

I've been into RC for years, just not boats. Still in the planning stage on this one so some pics would more than helpful since that is the same boat I'll be building. I assume you run a 2028. What ESC is that? CC Hydra?

So you are saying you have to build up the floor of the hull with sheets of fiberglass and resin? What happens if you don't do that? Vibration or worse? Will it not be as fast or...?

What prop were you running in the vid? Was that the best one you've found for that boat so far?


Thanks for this info I really appreciate it all.

JTL

[Make-a-Wake]

Here are some pics...............the whole build thread is here on OSE in boat building.

You need to use some type of glass/cloth reinforcement, the hull is pretty thin............in the "final run" vid below i either hit a turtle or the hull just gave out right in front of the stringers in the bow. I believe i used an x457/3.........

it was running so well............kind of a shame...........

[jlanders001]

Nice. Being a pretty good DIYer as well, I like your motor and servo/receiver mounts. Nice and simple.

Couple of questions if you don’t mind… Do you never use any thrust bearings? How about brass tube supports? Didn't see anything like that in the pics.

What is your rudder offset from the transom to the leading edge of the rudder?

Sorry about the thing ripping in half on you. How fast were you going at the time? Did you ever talk to Vern (the guy that builds them) about that to see what he had to say about it?

[Make-a-Wake]

I made the motor mount myself..............cost about a buck in raw material and used stainless bolts. I have a tube support that is hidden in the pics above..............lemme try and find one. Dont know the offset measurement of the rudder but you can see from the pics where I had it. No thrust bearings, just the big teflon washer bearings behind the drivedog.

The ESC in the pic was only used twice and it fried..........went to a SF240hv..............which drowned. The motor and hardware now reside in my 47" mono in my signature that i hit 70 with. It was underwater for a week..............motor works fine. The 47 incher is a carbon/kevlar design and i added a good amount of epoxy support as well.............strong as an Ox.

Vern knows about the disaster..................i just pushed a boat that was designed for a gas motor and 40 mph too far.........i hit 63 with the 51" GT and the hull is just too thin.............must re-inforce it!!!

[jlanders001]

Awesome. I may have other questions for ya from time to time if you do not mind.

By the way, how did you attach the tube support to the hull? Epoxy?

[Make-a-Wake]

Awesome. I may have other questions for ya from time to time if you do not mind.

By the way, how did you attach the tube support to the hull? Epoxy?

Yep..........

[jlanders001]

Already have one: Can a BEC be used to power the reciever? How would ya wire that with 10S - just off one battery or something? If a BEC is not a good idea, how big was your receiver battery - how much MAh?