Hi boys!

I "just happened" to buy an Brodak Cardinal ARF today  Electric propulsion? But ofcourse!  Does anyone have pics of a Cardinal with electric motor? I need some ideas on how to mount the motor.

I have two motors on the shelf, one Turnigy 35-48 800kv 600W standard (gold) edition and one Turnigy SK 35-48 900kv 770W "pro edition". Which one? I would like to use the 800kv 600W motor. I also have a Phoenix 35 ESC can I use that or do you think I need the 45?

/Andreas

Dennis:

C/L has never been so much fun for me as it has been since I started with electrics   I have a lot of projects in the pipe right now:

E-Legacy (kit)
E-Vector (kit)
E-Banshee (kit)
E-Cardinal (ARF)
Nobler (ARF) Glow model (my last) that will be converted to E it it isnt to damaged by fuel.

The problem is that I doesn't have the time to build models from kits or plans with two small kids, work and army commitments so I will need to stick to ARFs for some time now. I have put the contruction of the Legacy and Banshee on hold until I get some more time.
I bought the Cardinal because I want a more modern model then my E-Nobler as I try to learn the pattern and it goes together fast. Cooling will probably not be a problem with a profile model  

/Andreas

Andreas,

... I would also mount the motor and battery towards the inside of the circle to maximize cooling effect ...............

Keep us informed!!

Archie Adamisin
Muncie, Indiana

On my Twister, I originally mounted the battery on the inboard side (the motor is dead center) - After completely filling the tip weight box (and still needing more), and chasing a dutch roll on hard corners, I moved the battery to the outboard side, removed most of the tip weight and the plane flies much better, although I still have the dutch roll.  I would keep my options open on any plane, but remember that we also do not have a 10-12 oz. engine/muffler hanging on the outboard side (and doing the job of some of the tip weight) - so each design will need to be analyzed in advance.  For instance, I built the Twister with equal span panels which probably requires more tip weight than one built with a bit of asymmetry.  Keep your options open .... and accept that onlookers might just have to tolerate the sight of your battery.

Mike made some nice points but also consider:

On my profile ECL's I have been trying to "pocket" the battery and install it from the inboard side.  The reason is I want the centrifugal forces to hold the battery in and the straps or rubber bands to only keep it from falling onto the ground when the bird is at rest.  To accomplish this on the Cardinal you have to cut through the cheek cowl AND the fuselage.  On a different bird (not a Cardinal) I used a rotary ZIP saw and kept the outermost ply doubler intact.  It would be easier to just jig saw through the entire fuselage, then reinstall some retainers on the o/b side of the fuse.  

The fuselage with doublers and the cheek is about 25mm thick,  the 4s2600 batteries I have been using arou roughly 35mm thick  Thus only 10mm of the battery is exposed.  HOWEVER as Mike points out, the battery weight IS offset to the inboard side.

BUT WAIT!  Check your wing.  The Cardinal use a cut-away wingtip on the i/b side, and a solid tip on the o/b side.  This results in a pretty sizable o/b weight bias.  For example, on the IC powered Cardinal I assembled a couple years ago, the model had EXCESS o/b tip bias with NO tip weight installed.  The point is that (Mikes cautions not-withstanding)  having the battery offset to the i/b side is not necessarily a bad thing!

(edited to fix the biggest spelling blunders...)   

This site is wonderful, just ask and people chime in to help  Now, if only the rest of the world would work in the same way.....

The battery "pocket" seems like a nice idea, i might use that!

Will: Thanks for the pointing to your Cardinal pictures. I would really like a dual support motor mount like Crists, but if your mount have lasted over 100 flights I will probably do something similar as it is much simpler to make with ordinary hand tools.

/Andreas

Andreas:
Sounds like you are off to a great start.  Are you going to be able to center the motor on the built-on nose ring or are you going to cut that off?

I have never done it on a motor that size but it probably will work if:

* Make sure the self tapper sticks all the way throu thg mount and doubler, it must be at least 1/2 " and preferably 5/8" sticcking through.

* "Toughen" the mounting holes with thin CA.  I'd think that wold be a very strong mounting system.

Some pics:

Hi Andreas,
 I like the way you did your installation. My motor centered up pretty well also. Instead of self tapping screws I used 4-40 threaded inserts for the rear screws and just matched up the 3mm holes for the front and used the stock inserts and screws. I  considered drilling it through and using blind nut that would have been placed under the cheek but decided the work wasn't necessary with the little vibration and no fuel to mess things up. Your mount looks thicker than mine but make sure it doesn't flex. That why I put the front pieces on mine. With over 100 flights on mine I've never had any problems. I did change the leadouts on mine after about flight 80. That was after I had a failure on another ARF and wanted to be safe. After inspection I can tell you that these leadouts would have failed in the not too distant future. Keep in mind that my Cardinal was from the first run. I have heard that the later runs were supposed to be improved.

Andreas,
My battery mount is just 2 pieces of 1/16 music wire bent into a right angled U and pushed through the fuse from the back. You can see it in the SV11 thread. The ends are bent into hooks after it is pushed through then I put some plastic tube over it cover the sharp edges. I can take more pictures when I get home later today if you need me too.
William

That should work fine. I used the wire and rubberbands cause that's what I had on hand the day I did this. I was just looking for something light,effective, and simple.
By the way, I couldn't open your pictures earlier today, It looks like you have room in front of your motor mount to put another small L bracket. That would eliminate any wiggling you have at all in the motor.

Will,

Yes, I could probably make two L brackets but it will be tight. I solved it in another way, as my motor mount is glued to the airframe I simply did a small support between the lower/most inward part of the motor plate and the bottom of the engine cut out. That cured the last wiggle.

Thanks for the photos, I cant see the 1/16 music wire on the inside part of your Cardinal, is it hidden under the covering?

What did you use to glue your wing? Epoxy, CA, White glue, etc...?

/Andreas

Hi all

The Cardinal is soon to be finished  I have the propulsion system finished and I straightened out a (somewhat) banana shaped main wing today. This evening I will make a carbon pushrod and put a threaded coupler on the bellcrank pushrod. All pushrods will have ball links. I'm also waiting for some parts from Tower Hobbies and RTF lines from CL-Central.

/Andreas

Hi Andreas,
Well check the vertical CG, it's not necessary to fly the plane, simply assemble everything else and hang by the leadouts. Use a level to assure that the wings hang vertically. Yes you could do a weight and balance calculation along the vertical axis, but unless you know the finished weights of all the pieces, you will still end up making adjustments to vertical CG with battery position. I suspect that a moderately high battery location will offset the landing gear mass.

That battery adjustability will eventually become commonplace just like adjustable leadouts did.

later,
Dean P.

Hi Andreas,

I don't think you will have any problem mounting it over the wing in a straight line. Mine is like this and flys great (>250 flights). I do have a HD LG for the 56 oz TO wt. that is also 1" longer than stock with large wheels for the tall grass I fly in. Here is an old photo (still looks the same):

http://stunthanger.com/smf/index.php?topic=5823.0

BTW: The MM I use is a beautiful unit made by a very nice guy way up north. I don't know if he still makes them available? This is the cleanest way to mount our motors on a profile. But for people like me who are "metal challenged" your DIYS mount is excellent, I love it! :-)

Kas has a nice one for our profiles, but I have not been able to get one from him.

BTW: My battery mount worked out better than I thought it would. It could be made lighter, but I have been too lazy to change it. The screws go through the metal mounts into the Velcro along with CA. It makes battery changes very KIS and easy to do (remember, I'm very lazy ;-).

Keep your E fleet growing .... We need more semi scale E planes out there, maybe in a few decades when your kids are off to college etc., you will have more time to build one? ;-)

Regards,