octura prop help

[hurricane]

Can someone please help me with a little problem I am having.
I have been using a X640 prop works great.
A friend told me I should try a 2132 or even a 2135, but when I use this prop all I get is prop cavitation really bad.
This is in a 3 cell lipo rigger. 540L I know I can use a prop with this much pitch nothing gets even warm when I use the X640 prop.

Please help
Thanks
Bill

[ReddyWatts]

which 540L motor and length of hull are you using?

[Fluid]

2100 series props seldom will take off well from a dead stop. Toss the boat florward parallel to the water, with the throttle pinned just as the prop hits the water. It should run okay then. Because these props have a LOT of lift you may have to flatten the strut or shift the CG back a bit to eliminate hopping.


.

[ice329]

I probly should not answer here but why not try going to a X642 if it will fit. If nothing is getting warm with a X640, the X642 is a bit more prop.

[hurricane]

Ok the 540L I am using is a 9L with a 3 cell lipo the hull is 23 inches.
When I put the rigger in the water, the prop is about 1 too 2 inches underwater
I don't get any hopping it just goes really slow and cavats really bad.
The only way I have been able to get any kind of speed from using this prop is if I weave back and forth then it will catch some what and take off .
one of the best ways is for you to watch the video I have, it gets a lot better at the end of the video here is the link.
http://uk.youtube.com/watch?v=htdI3aOIG2E
I really would like to get more speed out of this set-up
I also have 2 other videos of the it please watch them and give any help you can.
Thanks
for all the help guys.
Hurricane

[ice329]

Hurricane, I just pulled out the prop chart. Looks like those two props you mentioned are smaller diamiter the the X640. I would say that is causing the problem. You said the X640 worked good its diamiter is 1.57 inches, its shaft size is .187 the other two are 1.38 and 1.26 and shaft is .125 are you useing a sleeve. If the X642 fits and you can find one try that, or the 2140. Nice boat it hauls when it grabs.... well G/L

[ReddyWatts]

FeCalc estimates it is using around 90 amps with the X640 prop. The X642 will use about 110 amps.

[hurricane]

How did you get it is using around 90 amps ?
When I use my friends datalogger it runs around 68 amp and peaks of 88
when I start using a prop bigger then X640 at top speed I start getting alot of prop walk.
So I wanted to go to more pitch and smaller prop so I dont have so much prop walk.
I have 2 different flex shafts so I can use props for 3/16 or 1/8.
Is there a nother prop I could try maybe what about the 19 or 17 series ?

Thanks for all the input guys
Bill

[ReddyWatts]

Be careful using the average reading. Go by your maximum peaks for controller life safety.
FeCalc estimates max load readings. It has always been close when looking at max readings on 2 pole motors.

[hurricane]

I have tried to use FeCalc but there is no settings in it for the lipo's or motors I use and some of the props.
Is there anything else I can do or do you have one set up for feagio motors and lipo's ?
If so could you email me or post the set-ups for it ?
Thanks
Bill

[ReddyWatts]

You may download the text file below into your fecalc program directory. It has some of OSE's Fiegao, KB45 and Neu motors. Also the NeuEnegery lipo's 1P and 2P.

This is the FeCalc program.
http://www.rcboataholic.com/fe_calc.htm

There are many variables in FE boating that keep this from being an exact science. These calculations are only ball park figures. FeCalc is great tool to help you find a prop to start with on a new build. Always start with a prop smaller than what you calculate for max amps and then work up to the larger prop as heat and amps allow.

Use the "Hydro / performance" setting when calculating a 4-pole Neu motor in a cat or mono hull. The amps will read too high if you dont by 20 -30%.

[hurricane]

thanks alot that helps me out a ton.
not so much guessing LOL.
Well i will be looking to do more testing more this week end, will post back to let ya know how thing work out.

[hurricane]

ReddyWatts
please take a look at this http://uk.youtube.com/watch?v=P6s36DvCivY
I used FeCalc and helped tons thanks so much.
The testing in this vid is being done with a raw X632 prop not polished or sharpened
or anything just right out of the package LOL
wanted to make sure it was going to work before I put all the work into the prop,
unlike my 2132 and 2135 props hours spent on them.
Also I was wondering is there any way FeCalc will work for amps and so on for an Align 600XL 1650kv on 4 cell lipo ?

Thanks again for all the help
Bill H

[ghostofpf1]

Also I was wondering is there any way FeCalc will work for amps and so on for an Align 600XL 1650kv on 4 cell lipo ?

Thanks again for all the help
Bill H

You just need the motor parameters so you can edit the fecalc.txt file with the new motor numbers.Enter each parameter with a single "Tab" seperating them per the instructions and save it and the changes should show up next time you fire up fecalc
HTH
Ghost

[hurricane]

I have tried looking everywhere for the specs but can't find them.
Even from the Align's web site.
This is a multi pole motor. its from a Align T-Rex 600 heli.
There is a guy on youtube using 2 of them in a cat and man that thing halls.
its called miss fortune heres a link to it.
http://uk.youtube.com/watch?v=59cn54QVTEE
I want to use the same set-up with one motor and stuff it in a rigger :)