68 inch outrigger

[Nevs]

I have started the work on a 68" outrigger. What I know: 1) It will have 2 motors. 2) I will use 2x YEP 180. 3) I will use 12s1p/5000 to feed both motors. The rtr. weight will be around 6k.
I would like to go a bit past 100 mph..( at least the theoretic possibilety) Any surgestions ?
I have some thing like a pair of 4082 in mind. In the 1200-1500 kv area ?..
I have ordered the Hydro & Marine "strutless strut" because It makes it possible to make a very low rear...But can a 3/16 flex do the job ?

http://www.rcgalleri.dk/fotoalbum/teknik-projekter/36239-project_190_kmt_

[rol243]

if your going to use this strutless strut you should also use a pair of Wire Shafts not flex shafts as you will get too much drag for SAW use. have a look at the 3mm wire shafts plus you can buy matching collets for the motors to fit the shafts.

[Fluid]

I have set over two dozen SAW records, so I know at least a little about the subject. 100 mph is not difficult to achieve today, you really only need 4s or 6S power in the right hull. If you want a big 12S rigger then I suggest two 4092-size motors each with a Kv around 1000.

I know nothing about the H&R strut you are using, but you can use 3/16" L/R cables and x457L/R props. Don't believe everything you read, you absolutely do not need wire drives, but there is nothing wrong with wire if you want to use it, I've used both. Cable has pushed 4S riggers to near 140 mph - timed speed, not GPS BS. If the rigger is properly designed and set up you should see speeds in the 105-115 mph range although your rather small ESCs might be an issue. Or not.

Will the battery (12S1P/5000mAh) supply one motor or will you have two of these packs each supplying its own motor? Best to use two packs, each supplying its own motor, but a single pack may work if you don't need much run time.


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[rol243]

Fluid, i did suggest the use of wire drive shafts going by the actual length of the tub, as you can imagine 68 inches is one long rigger and depending where the motors are positioned the long lengths of flexy shafts not only weight but some extra drag in the lines would no doubt occur. i have recently found the wire shafts combined with quality minature bearings set into the brass log housing works extremely well. i have officially had a SAW time set for my 45 glow rigger at 192 kph using this method of drive line. this method is new to me as i,ve always used flex shafts in the past 40 years i might add but times change to the better i have noticed. cheers.

[Nevs]

Thank you both. I will try out the flex first then..I have no experience with wires. But what I can find and read you will need a strut with BB. Teflon bearings will no do ?..And it seems that it is easy to do it wrong and hard to do it right ?..So maybe later.
It is the plan to supply both motors with 12s1p. I got 2 TFL sss 4082/1300 kv motors from a freind, almost for free, so I will use them, and see how it goes. Will start out with some small 42mm 2 blade.

[Nevs]

Think i can link a video in about 14 days... But only on 8s/46mm...This small lake is always calm but only about 100 m long.

[srislash]

Thank you both. I will try out the flex first then..I have no experience with wires. But what I can find and read you will need a strut with BB. Teflon bearings will no do ?..And it seems that it is easy to do it wrong and hard to do it right ?..So maybe later.
It is the plan to supply both motors with 12s1p. I got 2 TFL sss 4082/1300 kv motors from a freind, almost for free, so I will use them, and see how it goes. Will start out with some small 42mm 2 blade.

Ummm, 12s?? That may be a bit much. I would think 10s would be screaming on 1300kv. Just my opinion

[Nevs]

A lot of "people do" 2600 kv on 6s. Or 3900 on 4s. Nobody does 1300 on 12s..Well time will tell..

[srislash]

A lot of "people do" 2600 kv on 6s. Or 3900 on 4s. Nobody does 1300 on 12s..Well time will tell..

Y'know, you have a point there. Lower KV holds a loaded rpm in my findings. Myself I run 1020kv 4082's on 12s in a cat and am up in the trip digits. That is all I was really comparing to. My setup loaded turns 44,000rpm. Just knowledge for you. I have logs if you want more .
Shawn

[Nevs]

Thank you. But I do not think logs do mutch good. I ran logs on 2 boats. ESC and motors were overloaded according to logs..But everything was very cool..But yes lower kv motors holds the rpm...If you got the batteries.

[srislash]

Yes I agree on the logs. I am trying to smooth them out on my Castle ones. I can't really count the 1/100th second peaks for much. My EagleTree ones are much better

[grsboats]

My twin rigger (41,5 "lenght) is feed by two 4092 2080kv on 6S and two T180 modded with extracap banks turning V947 mod and reached 106mph efforteslly so for this boat size (68") I would follow Fluid directions as it is a big boat too and lower kvs will let you turn bigger props controlling amps with no worries.Gill

[Nevs]

Ok Thanks. Are you using 3/16 or wire ?. And what is the rtr weight of your rigger ?

[T.S.Davis]

Best to use two packs, each supplying its own motor, but a single pack may work if you don't need much run time.

Unless he's running IMPBA. IMPBA doesn't allow that. Nobody has a real reason why. You have to combine the packs and then split them back apart to feed both ESC. Stupid in my opinion. If you have two ESC you should be allowed to have two sources at the given voltage.

Speaking of running with an organization......why 12s and why 68"? There is NOTHING wrong with building for your own satisfaction but who knows........you might, maybe, possibly decide to run it through some traps for official numbers in the future. Both major organizations only allow 10s and 60". You certainly don't have to do 12s or 68" to crest that 100mph mark.

[Nevs]

I am in no org...Was thinking that I just solder the ++ and -- of both the esc...68" I believe should be a "good size" where you can experiment with a lot of different setups. With some changes, (drives, esc), a pair of TP 4070 and 18s1p/5000-xxxx could be possible....Maybe.