Firefly EPP

[Peter Royall 47]

 

I got one of these for my birthday last year!

Has anyone fitted a brushed motor and ESC, as i have an abundance of these laying around. Just wondered how to fit, as it would probably involve a redundant motor mount reinforcer.

As there are no instructions come with it, the pictures on this thread are very helpful, thanks.

TTFn,

Oily

 

[Bravedan 106]

 

Well.............................

 

Have to say personally I would not even contemplate a brushed setup on the FireFly. A brushed motor of sufficient power will be too heavy, one thats light enough will be underpowered.

 

The whole concept of the FF is that its set up overpowered to the extent that you don't use the power except in ultra short bursts to make it do what it was designed for, have huge throws and alter direction instantly by using lots of prop wash over the large surfaces. It obviously will fly with far less power, but then its just another plane, could be anything. You DO need that power and throttle/thrust response.

 

My usual "outdoor" one has a "tuned" Hacker A20. It also has a 3 axis gyro to eliminate the torque/precession reaction of going from zero power to over 200 watts instantly! Flies outdoors on a 800mAh 3S, no larger.

 

My 2 other mainstream indoor/outdoor ones, which fly outdoors perfectly well, only have £5 A2204 motors and 12A ESC's costing £8, so sorry, but IMO trying to use brushed is only going to lead to disappointment, OK?

 

[Bravedan 106]

PS, I can loan you my original combat one if you'd like a prod and a poke and a fly. It's survived four full seasons of indoor combat and flies OK outside in less than 10mph.

[Peter Royall 47]

 

Thanks for your comments Dan, I am about to start this project!

Just trying to figure out the best way of attaching the directional surfaces

Oh! and how to sand the leading edges, my file sander is not interested!

Oily

 

[Bravedan 106]

 

Peter.......

 

1. Do NOT sand the leading edges, it'll ruin its handling. You will have two layers of foam, the main sheet and the KF section. Use a sharp scalpel/knife and cut the upper main wing LE off at 45 degrees. (ruler guide and angled blade)

 

2. The best way to do the elevons is:

 

a) cut them out of sheet

b) chamfer them at a min of 45 degrees on the underside with a knife to allow rotation. (I try to get at least 60 degrees surface movement each way)

c) put a small bead of UHU POR along the point of the chamfer.

d) put a small bead along the main body where the flying surface bead will touch.

e) allow to near dry

 

With main wing on flat surface slide elevon square up to wing and it will adhere (what is called a POR hinge)

 

Ideally do not tape, but if forced use Blenderm NOT reinforced tape.

 

[Bravedan 106]

 

If you do need to sand EPP any time, (and the FireFly is NOT one that benefits) then do NOT use normal sheet abrasives, use coarse and medium "Dry Wall Sanding Screen". This used lightly gets a smooth finish with no tears as it does not clog.

 

Dave (builder of 100 plus EPP planes over the years inc five FireFlys).

 

[Peter Royall 47]

 

Thanks Dave

I was just reaching for the sander........................................

 

Oily

 

[Martin 0]

 

This is reminding me to build mine, too!

 

At the moment I've got various sheets of foam still taped together from being posted to me, two copies of the plan printed out at A0, and various parts bought from HobbyKing based on the BOM suggested by the designer on the original RCGroups thread (including a couple of 3S 500mAh batteries).

 

Maybe this should be next on the build queue! I'm always jealous when I see other people with them at the field.

 

[Peter Royall 47]

At last I finally finished building the Firefly after loosing the plywood motor mount which fell into the abyss of junk in the model workshop!

I used servo,s reclaimed from a deceased Wot-4 foamie with wire pushrods,  a 22D-28 electric motor with a pusher 7 x 5 propeller. the ESC i used to begin with was an 18A, but the motor complained and could only fly with 1/2 throttle.

A larger ESC available was rated 35A, and this cured the problem.

The Firefly hand launches with a grip on the outer wing and half throttle, Just bung it slightly skyward, and once airborne and stable, increase the throttle until some height is gained, making it possible to trim the controls for SAL flight.

The model is great fun to fly and runs on a 3 cell 1300 Lipo for quite some time. Flights at zero height are very possible and quite fun, some aerobatics are possible, but be careful not to rip the fin off!

Firefly kits may be available from Rob at Avicraft, Chatterton road, Bromley, Kent. It might be prudent to check stock before travelling.

Have flying fun,

Oily