Greg Covey

Marshall,

You don't use a spinner on a Corsair, just a hub. If you don't like the Graupner prop adapter then use a [link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXL745&P=ML]Harry Higley Safety Spinner Hub[/link] at Tower Hobbies. Horizon hobby may sell them to but you'll need to order the metric one for 6mm shafts.

Yes, a 16x8, 2-blade prop on 20 cells will work fine. It should draw around 45amps depending upon the voltage drop. The thrust will be more than you need.

Longarm

My Feedback: (1)

I agree Greg, but I have the P-51, not the Corsair. Man, you are working too hard.

First I am Mitch,

Now you suggest my using a Hub on the front of my P-51.

LOL........

Longarm

bassmanh

My Feedback: (5)

longarm,

hes still thinking about me and my corsair i think and i DO have a hub on my corsair

still hoping to fly it for the first time tomorrow night and then post some pics.

Greg.

i posted a question for you on the kokam raises the bar again post . let me know what you think please.



mitch

Greg Covey

Ahh, sorry. Yes, too busy, indeed. I average 10-20 R/C related e-mails a day and used to keep them straight when I was younger.

A second P-51 kit you have then. Another guy that e-mails me is trying the H9 Corsair. A P-51 definitely needs a spinner! Tru-Turn makes a new E-cut for APC props that I started when I sent my prop in for fitting on my Graupner Extra 300S. They don't seem to advertise it yet but you can order it.

Anyway, the specs for the H9 P-51 and the Corsair are virtually identical so the information is good for both warbirds.

Longarm

My Feedback: (1)

Greg,

6S2P pack on order for the new Stang. It is not the 20C pack though. It is a new 12C Tanic 2550 pack. (Four 3S1P's wired together, like your Kokam setup)

It will have 5100 Mamp and can handle to 60 amps continuous. I will not come close to 60 amps in whatever setup I go with. That will bring the estimated AUW to 8.25 lbs!!!!, which is lighter than the heavy range of the suggested 7.5 to 8.5 lb for the glow version.

Longarm

Greg Covey

Marshall,

That sounds great!

I haven't tried the Tanic cells yet. In general, the Lithium cells hold their voltage under load better than NiCd cells so you'll likely see more power as a result. Be sure to re-measure your current on the new setup as a sanity check. As long as the continuous current rating is close to your max. throttle setting, it should last a long time.

You may want to also consider a 2nd UBEC just for your retract servo. I am contemplating this idea when my Corsair is due for an inspection or repair. We have a local electric fly this weekend so i'll give it another workout.

Longarm

My Feedback: (1)

Greg,

I am trying to picture how you would use a second UBec. Would one Ubec be hooked up normally and the other splice the wires from Ubec to the retrac wire and plug in the other Ubec wire into the reciever for the retracts? Would that cut off the power to retract if the retract had a problem like binding? Is that how you are talking about using it? or am I totally off here?

I actually thought of putting two recievers in the plane on the same frequency. Use one micro reciever for the retracts only, the other reciever for the throttle, rudder, ailerons, and elevator. Wire in the retract reciever into the 4th battery or just use a single Lipo. Use only the retract channel with that reciever. Would this work? Can you elaborate on the second UBEC idea?

Thanks...

Longarm

Greg Covey

Marshall,

Yes, it sounds like you got it right.

Connect the first UBEC as normal then connect the second UBEC as follows:
[ul][*] Retract servo ground, Rx. ground, 2nd UBEC ground all connected[*] 2nd UBEC 5v line to retract servo only (don't route to Rx.)[*] Retract signal line to Rx. as normal
[/ul]

So basically, the retract plugs into the Rx. with the +5v wire removed and soldered to only the 2nd UBEC 5v output. All grounds are connected together and the retract signal line goes to the normal Rx. channel pin.

You could modify a "Y" adapter cable to do this which would leave the other component cables unmolested.

flyanything

Greg,

What thickness of aluminum did you use for the motor mount extensions? BTW, I've received most of the parts from Hobby Lobby that you listed in your review. I'm part way into the build but the AXI motor is backordered. I'm hoping to fly it at our clubs war bird festival on 6/26. Also, just wanted to confirm with you that the AF109 lithium charger will charge the whole 6s4p pack at once. The site says it has a nine cell limit but I assume that the charger cell limit applies to the pack "series" number, is that correct? I have a Triton but am considering getting the AF109 for this and other future large pack projects. Are you using the 15-20C Kokam packs on anything yet?

Also, thanks for doing such a great job on the reviews and making it easier for the rest of us to attempt projects like this one. I know it must take lots of time/effort to document the whole process and just wanted you to know that it is greatly appreciated.

Thanks,
John

Greg Covey

Hi John,

Thanks for the kind words. We like to think of it as "a labor of love".

The metal plate extensions were 1/8" thick. Too bad about the AXI being out of stock. I'll make sure they see this post and perhaps prioritize your order in some way.

Yes, the AF109 works on packs up to a 9s voltage and about 8amps current. I've used it up to an 8s pack but kept the current to 4amps. On the higher voltages, it takes 2-3 times the current to get the desired output current.

I am using both 15C and 20C packs. Check out my threads for the Graupner Extra 300S, Great Planes Super Slinger, and other posts in the E-flight Power Sources forum. The packs are very different sizes so keep in mind the application when deciding which one to use. In the Corsair, space is not a problem.

We'll be giving the Corsair a good workout this weekend. If all goes well, i'll be installing my smoke system from my Graupner ShowFlyer to use with smaller cartridges. My goal is to mimic the smoke cloud when starting up the "engine" on the field. It will be an unexpected effect at electric meets.

flyanything

Smoke at startup, that's a great idea! Keep em guessing! Would be great if you can find somebody to shoot some video of that and post it.

HL has been a good source for me, very helpful. I forgot to mention that your Alfa Corsair review was also helpful when I built that plane a few weeks ago. It's flying great now that I finally got the brass pinion to stop slipping on the output shaft (red loctite). So I know what you mean when you say you are not a fan of gear boxes and pinions. Will be neat to have the Alfa and the H9 Corsairs sitting side by side at the festival.

You've inspired me to try to learn more about electric power systems. I ordered the AF Super Whattmeter from HL (also on backorder) so I can experiment more with the various parts of the systems. I'm a software developer by trade so the engineering part is somewhat new to me (too bad FSU didn't require more EE for the comp sci degree!).

Let us know how the Corsair does this weekend.

John

flyanything

Greg,

Where did you get your MaxCim Charging Harness and 40-amp ATO-style fuse? The MaxCim Motors site has these two parts listed:

Switch Harness Assy.
Charge Harness Assy.

Do I need both of these or just the second one?

Thanks,
John

Greg Covey

John,

I just used the Charge Harness Assembly and modified it for Dean's Ultra connectors.

My favorite On/Off Switch when using a UBEC is now the Tower Hobbies [link=http://www2.towerhobbies.com/cgi-bin/WTI0001P?&I=LXJC15]System 3000 Switch Harness[/link] for $7.

The 40amp ATO-style fuses can be purchased on-line or at a rural farm and tractor store. One such place on-line is [link=http://www.midterminc.com/en-us/dept_70.html]here[/link].

Greg Covey

My Corsair is scheduled for one of the noontime demos at the upcoming NEAT Fair in September so I decided to replace my wire gear mains (not the retracts) with some Robart 653 series struts from [link=http://www2.towerhobbies.com/cgi-bin/WTI0001P?&I=LXES71]Tower Hobbies[/link].

My stock Corsair retracts still work fine but the plane does bounce on occasion when we have a less than perfect landing. The Robart struts will eliminate this problem and cost lest than replacing the entire retract mechanism.

The strut needs to be shortened to fit in the H9 Corsair. This cut into the spring chamber which required that the spring be shortened about 2/3 of its original length.

The modified strut looks and fits great! I'll post a picture soon when I complete my wheel well assembly.

Greg Covey

Here is my modified Robart strut installed in the H9 Corsair.

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Greg and others,

What do you think about the new "Actro 40" Series Brushless Motors" and the Actro 40-5 compared with the AXI 4130/20? The info says the Actro 40-5 can fly up to a 20 lb. plane and a 20" prop.

If this is the next step up in performance I'd much prefer to have that as the cost is pretty high to retro-fit.

Thanks for the info.

Mike

Greg Covey

Hi Mike,

Yes, it is true. The Actro Kohler motors are like the "Cadillac" of outrunners. This, of course, comes with the premium price too! The Actro 40 can handle higher currents than the AXI...but do you really need it for a 9lb Corsair?

I'm planning on testing the Actro 40-4 in a new 33% Hangar 9 Edge 540 shortly. Look for the new thread here soon.

Regards.

flyanything

The incredible amount of torque generated by the 4130/16 is what eventually did in my first H9 Corsair. One has to be very careful with the throttle at slower speeds as there is not enough air moving over the ailerons to counter the motor torque... she will role over. I can't imagine wanting to use a bigger motor on this model. I will be using the same 4130/16 on my second H9 Corsair but with a greater respect for the torque it can generate.

John

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My Feedback: (6)

Greg and John,

Thanks for your input, I'm also looking at using the Actro 40-5 for the Giant Scale Planes Corsair which is a little larger and about two lbs. heavier. Since I've never gone the electric route I didn't want to go through something like the personal computer and miss the latest update.

Another question, can I use the same ESC and what size prop would be recommended?

Thank you

Mike

Greg Covey

John,

*OUCH* Sorry to hear about your Corsair loss. The ill feeling will likely last a while but i'm glad to see that you're planning on making a new one.

I hope that you had the brake dissabled on the ESC.

Mike,

Use the Jeti 77-amp Opto ESC or similar Hacker Master Controller. The less expensive Jeti ESCs are similar to the Hacker ESCs with a limited set of programmable features to keep things simple.

The prop size, cell count, and max. current draw are negotiable. Typically, I start with a high cell count of lower capacity cells but at a 50amp draw, you'll want the CP2400 or GP3300 cells anyway. Use a 20" prop, if it will fit.

flyanything

Thanks Greg... and yes, the brake was diabled. It was an aborted approach, thought I'd just throttle out and come around again but she was already going pretty slow and I gave it too much throttle. The takeoffs with this motor also took some learning. I finally was able to make a smooth takeoff by slowly advancing to half throttle while adding right rudder. She would roll up to speed and lift off with little or no elevator up. The first and second takeoffs of this plane were near disasters due to my impatience with the throttle and elevator. I'm glad I was able to fly the first one enough to get the feel for the plane and motor... ending in an costly lesson... but lessoned learned I hope. I learned that with these bigger, heavier planes one has to give the prop a chance to accelerate the plane (on ground or in air), unlike the instant response of the smaller, lighter electrics I have.

BTW, I'll be trying the Robostruts on this second Corsair too.

John

bird-shots

John's Corsair will fly at least once more...and soon. You see he sold it to me the other day...at a weak moment...and I'm almost ready to install the motor. I'll be using an AXI 4120-18, HM 77 ESC, 14x8.5 or and 6S4Ps . This is the same setup that I use on my 9 pound .60 size World Models P-51...which by the way flies great.

geach

flyanything

I can't wait to see that! That wing is going to take some TLC to get back in the air but I'm sure you're up to it. Once I get my new Corsair built we can fly them in formation.

During hurricane Francis I built my Hobby Lobby Alpha Profile Jet with a Mega 16/15/3 in the Vasa 65 ducted fan. This model is so light it is going to scream with the Mega and a TP2100 gen 2!

John

bird-shots

Like I said it will fly at least one more time. If it does okay, we will definitely have to try some formation flying. As for the fix, it wasn't that difficult, just a lot of forethought in order to retain the critical dimensions and shape...I had just enough plane left to do that. Just finished building the motor mount and glued all the firewall and wing bulkhead in. It should be ready to cover this week. It would have been tough without Gorrilla Glue. With it, things like bulkheads, formers etc, don't have to be perfect, just close...it fills in the gaps. The flightpack came today and the covering, retract servo and motor should arrive later this week. Covering will be a patch job, but it should look okay...at least from a distance.

I'm documenting the repair just in case anyone is interested...you know me, I take pictures of everything.

Can't wait to see the Alpha fly. Sounds like a winner, I sure hope I can resist getting into ducted flight.

geach

Longarm

My Feedback: (1)

Hey you two Tallahasee residents....why dont you drive over to Jacksonville sometime and bring those big birds and we can fly them off of a real Navy runway.

http://www.mustangone.com/images/H9P51.wmv

We can fly the Corsair's and the Mustang in formation.

Longarm