Originally Posted by Aeroplayin

Here's the 78 thread:
http://www.rcgroups.com/forums/showt...53557&page=178

and here's the power thread:
http://www.rcgroups.com/forums/showt...33887&page=182

It took a while to get through the 78 thread because there are many posts with some really good information, but it's worth every minute if you are even considering the 78 Extra. There is also some power reports that make less sense so you have to be careful too. The bottom line is that Watts, thrust, and airspeed vary independently, and the idea is to find a motor that has the perfect balance for your type of flying.

The power thread is something you can jump in at any time because no one really expects anyone to weed through the tech stuff. We hammered out some really good data to this point and it's better to just ask.



I did, and we discussed options, but the 53’s are light for 3D with a 22 inch prop on 8S, so 10S, even at a lesser wind, with a prop size over 20, is not a good idea, IMO.

I'm somewhat new to the E-scene so I hope my questions or statements are not considered marketing propaganda. Just trying to learn more of why pilots choose this motor over that motor and so forth. I just have good success with them is all.

Originally Posted by Aeroplayin

So far, the Hacker A60-16M 215Kv, the Scorpion 225 Kv, which is not made anymore, and the AXI 232 or 259 Kv, are the leading 3000-plus motors for this plane, IMO. The reason we went with the 215Kv was so we could prop up to 21 and 22 inches without over-Amping.

The Scorpion 5525-225 which has been discontinued has been replaced by the SII5525-210: http://www.innov8tivedesigns.com/pro...oducts_id=1149

Since my 5525-225 threw all the magnets Innov8tive replaced it with the SII5525-210. I haven't run it yet but it looks nice. The 5525-225 was at about 3200 watts on fresh packs with a 22x10. I am thinking I may try the 210 on 12S with a smaller prop.

As we are waiting for the Control Line guys to finish their weekend stunt contest event (some of these guys are NATs champs) Tom and I took readings on the 21x10 Xoar PJN and the 22x10 Xoar PJN. After reading this info, there is something here to keep in mind because I also have some data from Frankjp, who owns this plane and converted it from the gas setup. The issue to consider is battery volts, and sag. The tests below are on 10S 40C Sky Lipo 5000mAh that were purchased a while ago and have about 40 flights on the Q80-7M motor we have on the 50cc Godfrey Extra 300, so they are not new by any means.

Frank sent me data on brand new Skys and Gens on this very same motor and prop collection, but I would rather he report his findings. I think we should also run them 6 to 10 times and wear thr new off of them and take another round of readings.

Here is what we have to day:
Hacker A60-16M
Castle Ice2 HV120
21x10 Xoar PJN
Sky Lipo 2x 5S 40C 5000mAh
Volts: 38.40
Amps: 86.88
Watts: 3382

I did not bother to recharge the battery when I replaced the 21x10 with the 22x10 so the starting volts for the second test was 41.11v as compared to 41.40v for the first test with the 21x10.

22x10 Xoar PJN
Volts: 37.96
Amps: 95.95
Watts: 3703

Here are the pics:

Originally Posted by cwojcik

The Scorpion 5525-225 which has been discontinued has been replaced by the SII5525-210: http://www.innov8tivedesigns.com/pro...oducts_id=1149

Since my 5525-225 threw all the magnets Innov8tive replaced it with the SII5525-210. I haven't run it yet but it looks nice. The 5525-225 was at about 3200 watts on fresh packs with a 22x10. I am thinking I may try the 210 on 12S with a smaller prop.

Nice... 23 oz and looks like it can swing the 22 inch prop all day at a 210Kv. About $70 more, but let me know how it works out. I've stayed away from Scorpion for magnet and bearing reasons, and AXI only because of the price.

I think someone opened the cage door in the power systems thread.

Got 3 more flights on My 48" MXS today. Feels a bit too floaty since I'm running 3s with a Torque 2818 900kv. Plenty of power but just too floaty. Gonna eventually go to 4s 820kv.

Natalie and Allen's glider (7 min 18 sec)

Well my plane budget just doubled from last year

Originally Posted by stgdz

I think someone opened the cage door in the power systems thread.

Close! the power thread and the 78 Extra thread. I had to ask about the power system and to Aeroplayin's credit he did try to steer us to the other threads but sometimes these things just happen. I for one am glad it did because I got tons of useful data to help me make some decisions on a 78" airframe power system.

Originally Posted by jw357_23043

Got 3 more flights on My 48" MXS today. Feels a bit too floaty since I'm running 3s with a Torque 2818 900kv. Plenty of power but just too floaty. Gonna eventually go to 4s 820kv.

Sound like you wouldn't be a good pa candidate. I like a slightly heavier wingloading too.
I still haven't moved the cg back on the 64mxs yet. If l get time and can get out of the dealership and dmv office tomorrow in reasonable time l will work on it.

Originally Posted by losifanatic

Sound like you wouldn't be a good pa candidate. I like a slightly heavier wingloading too.
I still haven't moved the cg back on the 64mxs yet. If l get time and can get out of the dealership and dmv office tomorrow in reasonable time l will work on it.

Yeah I didn't get too crazy with it. Did some blenders, harriers and rolling circles. It will 3D decent but could be better. Motor came down barely warm. Haven't tried to hover yet as I am a bit hesitant given the motor setup. Did you say you had a 14x7 on your Torque 900 kv 2818? Just don't want to smoke it and crash. May try to go out tomorrow and try to get the battery farther forward as I think the cg was off.

I got my power cord Y connector with on/off switch from Solid Hobby yesterday and took it out to the field today. It solves a lot of big problems for me. We have AC at the field but on a busy day outlets are at a premium. Since I now only use one plug instead of two, I'm a good citizen!

The switch is nice too because if you unplug someone will steal your outlet. This way you can just switch it off. Seriously, it's nice to not have to unplug two plugs every time a battery is done charging.

I like this little unit a lot. I'm going to have another one made up with slightly longer wiring from the power unit to the switch, and that will allow me to velcro the switch to the top of the power supply and keep things neaty and tidy.

Originally Posted by Doc Austin

I got my power cord Y connector with on/off switch from Solid Hobby yesterday and took it out to the field today. It solves a lot of big problems for me. We have AC at the field but on a busy day outlets are at a premium. Since I now only use one plug instead of two, I'm a good citizen!

The switch is nice too because if you unplug someone will steal your outlet. This way you can just switch it off. Seriously, it's nice to not have to unplug two plugs every time a battery is done charging.

I like this little unit a lot. I'm going to have another one made up with slightly longer wiring from the power unit to the switch, and that will allow me to velcro the switch to the top of the power supply and keep things neaty and tidy.

I saw those somewhere and kinda thunk id get one one day.

Hey Doc - looks like I'll be down with the family the week of thanksgiving.

MLT

Originally Posted by Doc Austin

I got my power cord Y connector with on/off switch from Solid Hobby yesterday and took it out to the field today. It solves a lot of big problems for me. We have AC at the field but on a busy day outlets are at a premium. Since I now only use one plug instead of two, I'm a good citizen!

The switch is nice too because if you unplug someone will steal your outlet. This way you can just switch it off. Seriously, it's nice to not have to unplug two plugs every time a battery is done charging.

I like this little unit a lot. I'm going to have another one made up with slightly longer wiring from the power unit to the switch, and that will allow me to velcro the switch to the top of the power supply and keep things neaty and tidy.

Good points in your situation.

A buddy of mine and I are probably going to set up a solar recharging station for lead acid batteries in a small shed at the field, and provide DC. I think the cost of running AC back to the pitt area would be a little ridiculous. Not sure how we will pay for it...will probably put a money box and ask people that use it to chip in a dollar per day or or something like that.

SOS does anyone have a EF 74" yak fuse laying around little damage ok it would be nice to be black and yellow but will take what i can get