New power

[Hurricane]

We are running 1/10 scale electrics with the AstorFlight 25 - 5 turn arm. on 12 cells. Using the same battery pack what would be the eqivalant in a brushless motor? What if any besides the ESC would be differant? Thanks, Ron

 

[AlanN]

I really don't know but since noone else does either (I assume)....I'll try to help.

What speeds are you currently running?

Average weight of the hulls?

Are you gonna go lipo or stick with the nimh's?

Will this be the new spec for your club racing?

I'm sure there would be a nemis or sim cheap B/L that would fit the bill.

Also what props? Are you allowed to use any or do you have to stick within a certain perameter?

 

[Andrewg]

Hurricane

that sort of equality is very hard to quantify or justiify - every brushless is different and no one has a dyno sheet for the 25/5 Astro use Somarium Cobalt magnets which noone else does which throws in a wild card.

Brushed and brushless have different power curves especially at the top end - brushed run a lower percentage of rpms. A brushless the same weight (12oz) and KV (1550) as the 25/5, it will be faster - much faster.

One problem you have is when it was adopted the 25 was a top performer in its class. like a B50-8XL is now.

The clubs could choose to step into the future just choose a motor which has a 36mm diameter and no more than 75mm long can - that should give you plenty to work with and motors under $100.

 

[JimClark]

Ya runnin CT or ERCU?

Jim

We are running 1/10 scale electrics with the AstorFlight 25 - 5 turn arm. on 12 cells. Using the same battery pack what would be the eqivalant in a brushless motor? What if any besides the ESC would be differant? Thanks, Ron

 

[jayt]

The alternative could be a good 700 motor and 12/14 cells. No need to buy a new ESC, the motors last at least a season, and the more conservative racers wouldn't have to make the big change to BL. There is not a huge difference in on-the-water performance between the 25-5 and the SS-1.

Astro 25-5

Kv = 1531

Armature = 0.041 ohms

No Load = 4 amps

SS-1*

Kv = 1425

Armature = 0.09 ohms

No Load = 4 amps

* From FECalc

9

 

[Darin Jordan]

Ray Fuller ran a 1/10th scale from one of the two local clubs (can't recall... it was either CT or ERCU...) with a Nemesis 9L and that thing FLEW... right up to the point where the flex cable snapped... :blink:

Is there any truth to the rumour that the 700s aren't going to be made anymore???

I would think a good Hacker/Nemesis 9XL (1853rpm/V) or maybe a 10XL (1668rmp/V) would work great in the average Classic Thunder hull I've seen... Either "should" work fine with a Barracuda 80 or equivalent ESC...

I know you guys aren't looking for all-out speed, so the 10XL would be a decent combination of torque and revs... I'd go for the longest armature for the RPM range (XL vs L or S) you are looking for to maintain the torque... There tends to be more "wet" running boats from what I've seen at the 1/10th races, so you'll want the torque...

There is a guy in CT that is running the Mega motors in his Class II boat... those things have good torque numbers as well...

 

[Hurricane]

I would be running in E-RCU. Since the Astro isn't made any more I was just looking to come up with a reasonable solution for all. We all have to run the same thing so just looking for sugestions.

 

[JimClark]

I would be running in E-RCU. Since the Astro isn't made any more I was just looking to come up with a reasonable solution for all. We all have to run the same thing so just looking for sugestions.

Well there will be a Brushless Himax motor tested asd well as an astroflight 40 will be tested as well soo there hopefully will be a brushed alternative that is reversable and we can still use the current ESC's which are rock solid.

Stay tuned for more info int he next 3 to 4 weeks

Jim Clark

 

[AlanN]

I would suggest running the 700 motors with lipos.

Use the same size packs....I really like the 5000mah cells. 2s2p setup would give you all you need with very similar weight to what you already run.

You'll get the voltage like a 14cell setup but way less resitance.

If that motor does not have enough torque than a nem 8-9xl size can would be the next best economy buy in my book.

Darren I believe that these guys aren't as concerned about high output speed as much as consistant output.

Those well detailed hulls are so gorgeous that I would rather be able to see them race oposed to a blurr and a rooster. We have pushed what our 1/8th scales can do to the point (IMO) that it detracts from the class.

 

[JimClark]

Right on Allan your statements are correct. The problem with the 700 motor is it is not easially reversed as we turn left just like the big boats do.

Jim

I would suggest running the 700 motors with lipos.

Use the same size packs....I really like the 5000mah cells. 2s2p setup would give you all you need with very similar weight to what you already run.

You'll get the voltage like a 14cell setup but way less resitance.

If that motor does not have enough torque than a nem 8-9xl size can would be the next best economy buy in my book.

Darren I believe that these guys aren't as concerned about high output speed as much as consistant output.

Those well detailed hulls are so gorgeous that I would rather be able to see them race oposed to a blurr and a rooster. We have pushed what our 1/8th scales can do to the point (IMO) that it detracts from the class.

 

[AlanN]

Not trying to be rude U-40 but would you not just reverse the leads to the speedo? Along with the wiring of the caps?

Or would the motor just not work as well turning the opposite direction?

I haven't ran a 700 for years.

And if that was the case.....the 8-9xl B/L would be what I suggest still notknowing what your avg weight or prop is. What are you guys running...x445R????

But regardless of what motor I would still go lipo or sim.

 

[jayt]

Alan: some 700s have timing advance - reverse the power leads and the motor runs "backwards" but with the timing retarded, NOT a good thing...

 

[AlanN]

Alan: some 700s have timing advance - reverse the power leads and the motor runs "backwards" but with the timing retarded, NOT a good thing...

Shoot Jay,

I don't think I've been to a race yet were someone or something didn't run that way.(including me sometimes) :lol:

Yeah...thought about the timing thing on the drive home tonight.

I would suggest that since you guys are so limited on props...still have not looked up the OCtura or ABC cat to see whats available R/H......that the prop size would have to be the main deciding factor in their choice.

 

[JimClark]

Octura RH props are the 47 most use and the 42 too small. also the Graupner 45 carbon prop is popular.

jim

 

[AlanN]

My suggestion would be to call a vender who carries some nemisis or similar motor....tell him what your doing and ask for several winds of motor to test....maybe even for a small fee...If they were really nice and gave you a setup to run....they might get rewarded with a large order for motors.

I'm think maybe even up to a 10xl would be the most winds you would prob want. Just to keep the amp draw low for the larger prop. How many laps to you guys turn and what is the size of your course?