Who's running a Tranny in a FE boat?

[Meniscus]

Ok, who out there has or is running a transmission on a FE boat to reduce amp draw and allow for a larger prop?

Come on, I know you're out there

What have your experiences been and what motors have you used when doing 50,000 rpm plus?

[ED66677]

I made one out of scratch for my 8XL, under 18 NiMh cell (45k rpm at motor shaft) with a Hex 120 ESC, didn't last long, one lap and the ESC caught on fire! It was a blast!... and smoke!
I guess the ESC did not like the high freq. at this rpm!

[Meniscus]

LOL, good to here someone tried it though. I just know there are others out there that use them, but I need more info before I play around with it.

Thanks for the input ED.

[Steven Vaccaro]

I believe unless you have the motor already in your stock, you are far better off getting the correct size motor for the application in direct drive. In a smaller boat the gear boxes are ok, but as the boats get larger they tend to eat gears. Since the use of lipo I have been able to remove the gear boxes in my boats and use the same motors BUT change prop size. Speeds are now a bit faster, but more importantly I've reduced the chance of another area that "may" fail.

[Meniscus]

Aw, where's your sense of adventure Steven? Don't tell me you're getting old!

I may have a line on a guy that makes custom trannys, so at least I would have less chance of failure. Now, it may only be a reduction in failure by 5 or 10%, but I'm young and stupid. :)

I'm just wondering how many others use a tranny and what their experiences are. Good thoughts to think about though.

[Steven Vaccaro]

Aw, where's your sense of adventure Steven? Don't tell me you're getting old!

I may have a line on a guy that makes custom trannys, so at least I would have less chance of failure. Now, it may only be a reduction in failure by 5 or 10%, but I'm young and stupid. :)

I'm just wondering how many others use a tranny and what their experiences are. Good thoughts to think about though.

Well if you have someone that will make you a nice one with metal gears its a NEW ball game!! For a sport boat its a nice feature being able to gear up or down for speed or runtime.

[Meniscus]

I'm thinking of an edge: more prop, less amps, more fun!

Steven, since I'm still learning about the trannys and with regards to FE boats, are they designed with a centrifugal clutch to change gears if two speed? What do people use?

[Meniscus]

Anyone use a tranny in there boat? I know there has to be others.

[Steven Vaccaro]

3 or 4 years ago you would have had numerous responses. But lipo and brushless have put the death to gear box sales.

There are a couple of two speed gear boxes that mount on front of the motor that looked interesting years ago, but I never got around to playing with them.

[Meniscus]

Well, send me some links. I'd greatly appreciate any info.

I guess I'm 4 years late and a few dollars short!

[Steven Vaccaro]

Its been a loooooong time since I searched for those. PM Darin, he's been testing a couple.

[ReddyWatts]

trans

I used to run a Feigao 10XL on 18 NiMH with a 1.33/1 ratio trans on a X447 prop that used 66 amps. It was fun to play with. The motors seemed to really like the higher revs with less loading. I later learned that using a smaller prop like the Y537/3 would give the same effect for more speed without a trans.

[Fluid]

I run a Fine Design transmission in my Titan 40, the boat is 100% reliable and very fast. On 4S the Neu 1512/2D spins around 36,000 rpm with a 1.27:1 ratio and an M445 or M545. I bought the boat used with the transmission (a 24-cell setup) for a killer price, but the old tranny was pretty shot so I replaced it with a new one and decided to run it on 4S. This is one of my favorite boats to race, it handles just great due to the higher CG the transmission provides. The gears are plenty strong for 4S power.

If I was starting from scratch I'd do what Steve suggests and go direct drive with the appropriate motor. However if I wanted to run the boat on both 4S and 6S the gear drive is the way to go. It is far easier and cheaper to change a pinion gear than to buy and change out another motor.

Unfortunately, the overly restrictive and stilted length restrictions adopted by the US racing organizations have eliminated this possibility for racers. Now instead of just buying a new gear to race in another class - we have to buy an new hull, motor, hardware, receiver.........



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[Steven Vaccaro]

Jay I agree that within certain driving conditions gears are just fine. But I use my boats on a large lake with huge waves. The constant unloading and re-loading on re-entry would destroy them in short order. I realize its not the gears fault. Its more of an abuse of the parts, by the kids and I. I should have said that in my original post.

[Fluid]

Steve, two tips to increase the life of plastic gears:

- Always keep them lubricated with an oil that sticks. Most 'grease' just flys off as it heats up.

- Set them at almost zero lash. This works great - as long as the gears run on true centers - because this puts the strain on the root of each tooth rather than further up where the increased leverage will shear off the teeth.

The torque applied ot the gears also effects gear life. Run 6S with a 50mm prop and you can't expect long gear life. Like I said above, I'd run direct if I built the boat again, but for anyone wanting more versatility in voltage, gears are great.



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