24cells BL rigger prop ?

[pin]

Hi Guys

I had build a 24cells rigger use balsa & ply wood and some FG/Epoxy.
The hull length is 27" (30" with hardware) , hull width is 4.3"(17.4" with sponsons) !
The motor is Hacker B50-8XL , Master 99 navy ESC ... Sanyo 3300 nimh battery in 24cells ...5mm flex shaft and in direct drive.
The hull with motor ,ESC, battery, radio system and all hardware are all about 5.5 lb.
Now..i have a question...
What's props is the suitability for this setup?
I don't care runtime and i only want it fast and fast !

I'm sorry for my poor english :rolleyes:
Hope you can suggest me .
Thanks for your help.

Pin

[Don Wollard]

On that many cells - I think I would start with a 44-45mm lifting prop. The Octura 1745 (45mm and 1.7 pitch ratio) might be a good place to start. Riggers are funny animals - depending on the boats design and your CG, you might have some other options.

On my 24 cell riggers - we run either lifting props or 45/55 ABC props. The ABC props are not quite as fast but you get really good bite in the corners.

Oh! Whatever prop you choose - carefully monitor your motor/controller heat. In other words, don't run to far before you test you heat with each prop change.

[pin]

Don

Thanks for you suggest.
I'll test it defer to your suggestion.
Thanks again :)

Pin

[Andrewg]

Pin the 8XL is a 12 -18 cell rigger motor

on 24 cells even a X432 may overload it - certainly it will result in damage to the 3000's

The motor proably tops out at 16-18 cells - but you will have to use a small prop - y536-X438 on 16 cells and X432-Y536 on 18

You problems will not be with the motor. The most likely issue is g too much current draw from your cells and damage as a result.

[jevmax]

That's quite a range of prop size, from a 42mm to a 32mm? Where can you get props as small as an x432 with a 3/16 shaft hole? The smallest I can find is an X438 for that size shaft. In an application such as this, do you need to use a 1/8th stub shaft flex to accomodate the smaller props available?

[Dick Crowe]

Andrew is right. The 8XL might be too much for 24 cell oval racing. I run a 9XL with a x440 prop and Master 99 controller in my 24 cell boat and it's pretty close to the limit. On 18 cells I use the 8XL and again with the x440.

I can remember a few years back Chris Harris and Brian Vega running around 20 cells and the 8XL and their conclusion was that it was too much. I hope I've got that right.

Hope this helps,
Dick

[pin]

Dear Andrewg ...jevmax ... and Dick

Happy New Year & thanks for your help.
I know where is my problems .....
I REGARD the fastest speed result too much and viceversa forget other factor !
24cells look appear too much for 8xl .
I will try 18cells with a x440 or Graupner 2317.40 carbon props.
But...i still want to try 24cells with x435 or x432 for 8xl even the ESC or motor is damage !
Maybe it will did a 24cells new record ( in ASIA area ) :D :D

Thanks for your suggest and help.
Thanks again.

Pin

[Dick Crowe]

You're right. I use the 8XL for 24 cell SAW's but your only talking a few quick passes then.

To be honest, I think the 8XL is about as fast on 18 cells as the 9XL is on 24. Only a few MPH difference for me anyway.

Dick

[Andrewg]

Dick thanks for your info on that - I was thinking my prop estimations seemed small

[Don Wollard]

Pin -

We got you some good advise here. I stand corrected ... and agree with Dick on your motors performance range. Why don't you drop down to 18 cells and see what performance you obtain.

You will have a lot of speed anyway. Have fun.

[Dick Crowe]

Andrew,
You probably gave better advise, at least safe advise. With the kind of motor/prop combo I use the setup better be good. My boats run free and unwind. If you tried to run that combo on a heavy or wet running boat you're going to hurt something expensive.

Don, I think your advise is right on for the larger motors you guys ran. It wasn't an option for me. Hacker's largest motor is the XL and better suited to high RPM's. With the weight of 24 cells a larger diameter can and larger diameter prop would be a great combo. I can remember Larry running 24 cells a few years back with a 1415 2Y and ABC 45/55 in Alaska and it's still probably one of the fastest 24 cell oval setups I've ever seen.

Happy New year!
Dick

[Allan]

so what sort of boat fits round a C50XL6?

[Dick Crowe]

You've got me Allan,
I tried a B50 XL6 a few years back and couldn't really find a good application for it. I always did better with the 8L. It drew fewer amps, turned more RPM and was lighter.

The C series was developed for the emerging lithium powered vehicals. It's larger and finned to dissapate heat better and uses a segmented rotor for better partial throttle efficiency. Lithum vehicals run for a very long time where heat is a big issue.

In a boat we can water cool the cans to deal with the heat. Rarely do we run for periods of time at partial throttle so the solid rotor (the B series) is probably a better deal since it packs more punch.

Being larger the C series is heavier then the B series as well. FYI, the windings are the same betwen the C and the B.

It's nice to see Hacker making motors for emerging markets, although just because something is new doesn't make it better. I'll stick with the B's for now, although I wouldn't mind a C50 8L for my e-maxx!!!!!

Dick

[Allan]

Dick,

Thanks

It's not quite the same as the B it has more RPM/v, I also like the end plates - they are not glued in!!

[Dick Crowe]

As I have been told from Hacker the windings are the same for the C50 L and B50 L as well at the C50 XL and B50 XL respectively. Any increased RPM/v will be more a factor of weaker magnets in the C. Put a load on it and the B will outrun the C. The RPM/V spec works great when comparing apples to apples, but you've got some oranges in the equation now.

The bolt through construction is very nice on the C. I had to do an external retrofit on my emaxx to keep my 7XL from opening up! No troubles on the boats though.

Dick

[Andrewg]

Allan

the rpm arent that high given what NAVIGA guys run - have you tried a small (35mm) prop on 12 cells - with the higher efficiency it may be good in 5 minute format


Or - how about a hughey gearbox.....