Will this Electric setup work in a RingMaster

[Paul Taylor]

I had a Cobra 2020/12 970k motor and a Cobra 33A ESC. I have been looking over the specs on the inova8te website and I don't see anything that might not make this a compatible combination. Anyone have any input on if this will or will not work? Thanks

[Mike Morrow]

The picture shows a 2820/12 970K. I'm no expert but I'm pretty sure that's plenty of power for a Ringmaster. Go to the "List your setup" in "Gettin' all Amp'd up" sub forum and poke around. Look for an airplane about the same weight. There's a couple of Ringmaster's with their set ups in there. You can also go to Brodak's website and check out their electric power system's chart.

Mike

[Dennis Toth]

Paul,
If you use a 4S 1800 - 2250 mah pack and 9x6 APCE prop at around 10K it will give you around a 4.7 lap time on 60' C to C lines. On my Ringmaster I have use a BadAss 2320 - 820KV with 9x6.25 APCE -P at CC Talon 35 ESC, fixed rpm at 9650, Ztron Timer, HobbyStar 5S 1600 mah pack with a lap time of 4.66 (I like a little faster). The HobbyStat pack is ~70mm long and fits in the nose where the IC fuel tank would go, all electronics fit underneath.

Best,   DennisT

[John Rist]

Look at my post on Tom's ringmaster setup.
https://stunthanger.com/smf/gettin-all-amp'ed-up!/e-ringmaster-as-built-by-tom's-building-service/

Tom used a Cobra 2231/10 with a 9/6 APC prop on a 3 cell setup.  Dennis' setup looks good if you are doing a conversion.  Good luck.  Ringmasters rule.         

[Brent Williams]

Cobra 2820 970kV will fly a Pathfinder sized airplane.  It's way more than a bit too much for a Ringmaster.  It's not a matter of too much power, it is just needless weight to manage.

You'll need to define your needs a bit more to get accurate recommendations.
- Will you be flying the full AMA pattern or the Old Time pattern?
- Are you going to use 3 cell or 4 cell batteries?
- What timer setup do you intend to use? 
- The ESC brand selection is often based on which type of timer you intend to run. 
- The ESC amp rating selection will be based on your computed or estimated amp draw based on weight, prop, motor KV and the number of battery cells.

[Ken Culbertson]

Let me piggyback Brent.  The Cobra 2820/12 is a .46 size motor.  If you already have it then by all means use it.  The nice thing about electric is that they can be a .35 size motor with a simple timer setting.  It is the weight.

Ken

[Dan McEntee]

   Isn't a Fox .35 just a whole lot easier???
  Type at you later,
  Dan McEntee

[Paul Taylor]

Cobra 2820 970kV will fly a Pathfinder sized airplane.  It's way more than a bit too much for a Ringmaster.  It's not a matter of too much power, it is just needless weight to manage.

You'll need to define your needs a bit more to get accurate recommendations.
- Will you be flying the full AMA pattern or the Old Time pattern?
- Are you going to use 3 cell or 4 cell batteries?
- What timer setup do you intend to use? 
- The ESC brand selection is often based on which type of timer you intend to run. 
- The ESC amp rating selection will be based on your computed or estimated amp draw based on weight, prop, motor KV and the number of battery cells.

Thanks for the feedback. 😎
I will be doing the AMA pattern.
3Cell battery
FM9 timer

If I need a smaller motor that will work with the 30Amp ESC, what would you recommend?

[Paul Taylor]

   Isn't a Fox .35 just a whole lot easier???
  Type at you later,
  Dan McEntee

Yea if I could get fuel and no burping doing the vertical 8’s. And if no one complains if I fly off a neighborhood soccer field without a muffler. 😝 🤣😂🤣

[Paul Taylor]

Let me piggyback Brent.  The Cobra 2820/12 is a .46 size motor.  If you already have it then by all means use it.  The nice thing about electric is that they can be a .35 size motor with a simple timer setting.  It is the weight.

Ken

👍🏼

[Brent Williams]

Thanks for the feedback. 😎
I will be doing the AMA pattern.
3Cell battery
FM9 timer

If I need a smaller motor that will work with the 30Amp ESC, what would you recommend?

Paul, I would recommend using a Castle Talon 35 ESC since you are using the Hubin FM9 timer.  Might as well take advantage of the nice governor available with the Castle ESC.

You didn't mention the estimated overall rtf weight of the plane so I'll figure 32oz.

9x6 APC prop works well for this size airplane.

You'll probably want a minimum of a 3s 2200mah battery for 60ft lines and 32oz.

I would go down one size in motor to a 2814(3536) and save over an ounce up front. 
As you'll be in 3s configuration, you will need a motor that can handle a decent amount of constant watts.  I would look at motors with a minimum rating of 325w in 3s mode, but anything between 325w and 425w will be great.  I like motors with 5mm shafts, so I'm personally biased against using the smaller diameter motors which usually have 4mm shafts.

For 3s batteries, you'll want a motor KV around 1300-1400 for adequate headroom.  It's easy to throttle back a higher kv motor, but if the KV isn't available for your desired prop rpm, you are kinda stuck.  Err on the side of higher kv.

.02