wvr

I'm finishing of a Evolis, and building a Twister,
but really would like to see some pictures how to install the battery packs.
I don't want to make a to heavy structure, but on the other hand, the pack must stay in the plane when snapping

How much 'Velcro' is needed?

Do you make a box/sidewalls where the Pack are placed in?

Thanks
Winfried

Adamg-RCU

Winfried, this year Chad and I discovered what may be the simplest and most minimal battery mount. The two packs are held together with outer strapping of velcro or tape. The pair of packs has two small pieces of velcro on the outside surface that mates with two small strips of velcro on the mounting plate (permanently installed). Two outer straps of velcro hold the packs down against the plate. This allows lots of freedom to set the packs forward or backward to adjust CofG, but holds them firmly in position once strapped in.

For our Twisters we are going to add a second landing gear brace in front of the real one. Then a wood plate is set and glued on top of those braces, that spans the area between them. The plate will have strips of velcro, the packs will have strips of velcro, and there will be two velcro straps around the plate and pack to hold it down.

patternflyer1

My Feedback: (11)

This is actually a good idea for a thread. I couldn't find much about mounting the batteries when I was doing it.
Mine is sort of similar to what Adam is talking about. Here's pics.
Chris

Adamg-RCU

Chris, yep, that's what I was talking about, just applied to what is already inside the Twister.

-Adam

wvr

Hello,

Great Info!! Thanks already for these posts...

I found one myself... looking OK for the Evolis solution

Winfried

patternflyer1

My Feedback: (11)

Winfried
Doesn't it concern you that there will be a lot of weight in the belly of the plane. That IMO would affect knife edge, rolling manuvers, and also verticals.
I found this out flying alot of foamies. As example if you were hovering a plane and had alot of weight in the belly it would want to fall out and would require up elevator to sustain a vertical hover.
I also feel that having to turn the plane over to remove batteries would be uneasy. Although, I don't believe you have a removable canopy. Not sure about the oxalys. If I switch to the 3700's at some point I may have to go in through the chin cowl.
I would be curious to see how it affects flight.
Just giving you something to think about.

Nice plane!!!
Chris

can773

My Feedback: (1)

Chris,

There is no significant change in flying with the batteries in the bellypan, I had both and Enigma on glow and a couple of e versions (with the packs in the belly) and both had nearly identical flight characteristics.

As for turning over the plane, with a good stand its as fast as having a removable canopy and going through the top.

can773

My Feedback: (1)

Winfried

Here is a shot of how my packs are setup in my Enigma.

I have some small rails lengthwise inside the fuse where the velcro goes through to support it.

wvr

2Chris:

I hade my worries about having so much weight below the trust line, but based on other people experiences I decided to continue like this.
I will now first fly the plane and see what happens.... I always can put the pack in the fuselage but then I have to remove the wing every time to replace batteries, or make a hole behind the 'fire wall' (if you can speak of that with the electric planes ) so I can but the pack in the fuselage from there. We will see.

It surprises me that 2 strips of Velcro is enough to keep the pack in place, even when snapping the plane. But if it works, it works... and I have to get used to 'what is enough'.

Evolis will be flying like this is about three weeks .....

thanks for all the info
Winfried

patternflyer1

My Feedback: (11)

Chad,
I know you are knowledgeable about alot and I'm not trying to start an argument, lol.
I believe what you are saying with your planes, but don't see how it's possible that a few pounds if moved from center, to bottom or to top of the fusalage wouldn't make any difference in flight. I hope you can see what I'm saying.
Do you fly foamies? Haven't you had this issue with them? I have. I even have this problem on the simulator. I'm sure everyone has a simulator by now. Try changing the vertical cg in the fuse and see what difference it makes. If nothing else, it's an interesting experiment.
There is alot more to make a plane fly correctly, as you well know, than just setting incidence's and lateral balance. I know that you understand this Chad, not trying to state otherwise.
I just thought I would mention it as it's not something that gets discussed in the forums. But locally, here in Northern California we have discussed it with the electrics.
If faced with the same situation with the oxalys, or any plane with a one piece wing, I would probably mount them there also and just deal with it in mixes. Only problem with that is that I don't like mixes. I feel that a mix is quick fix for something inadequately built or set up. I do understand some planes just need a mix, don't get me wrong here.

Winfried,
I'm sure it will fly good regardless. It's a beautiful design.
Good luck to you with both your new toys.
Chris

can773

My Feedback: (1)

I dont have any answer other than no I didnt notice any difference, none in the mixes and none in the way the plane flew that I would attribute to the battery location. Maybe someone else might....I am just not that picky.

With the Twisters they are two peice wings with the packs mounted near the centerline.....so that will be a better comparison. Remember that with glow a significant portion of mass (engine head, and pipe) are below the centerline basically in line with where the packs sit so I dont think its really much different between the two setups (certainly not an order or magnitude...maybe 10%)....weight of fuel is a non-issue as the planes weighed the same without fuel.

I dont think I have ever mounted a foamy battery off the center of the fuse so I cant compare.

patternflyer1

My Feedback: (11)

The Twisters look really nice Chad. Hope you post pic's of them when complete. I'm sure you will though.
Chris

hwt

My Feedback: (17)

Chris... I am new in the electric pattern business and I looked at the battery installation in your bird. very neat... I loked at the proximity of your big batteries and your receiver. I am having a lot of trouble with radio interference with my install and it is a lot further away from the batteries than yours is. What is the white device on the left inside of the plane above your receiver and plugged into the receiver??? Any help would be appreciated... thanks Harold...

patternflyer1

My Feedback: (11)

Hi Harold,
Well, the white device is the regulator. I run a Jaccio perfect switch with regulator in all my pattern ships. I'm assuming you thought it was a choke. I haven't had need for one yet. I run Airtronics equipment though. What is your setup, maybe we can help?
Chris

hwt

My Feedback: (17)

Chris Thanks for the reply... I am running a 14mhz futaba system in an icepoint. I have an platt, extra 25-14 with a jeti 77 amp speed control. I am flying e-flight 5400mah packs x 3 for a total of 33.3 volts. As long as I have just 2 packs for 22.2 volts I have no problem but when I push it up to 33.3 volts I have radio lockout and interference that knocks my plane around the sky. I am running a seperate battery pack for the radio system. I really need the third pack for the power for the verticals... What might be my problem??? thanks Harold...

patternflyer1

My Feedback: (11)

As Tom has stated somewhere on rcu, maybe the axi thread, He had problems with the new receiver when he got his Futaba Mz. He wonders if its because they are so sensitive. I think there are others with your same problem with that system with the electric motors. I think it may help you if you try to run a choke on it. That's what Tom is going to try. I haven't needed one so far..
Chris