SDF

I have one of their other models ( Ethos LX41B Pro ). So far I've used it for NiCd, NiMH and LiPo but only from mains power. Seems to work well enough.

Hey Kids sorry to have to put a damper on things but Bluetooth shares the same 2.4GHz band as our radio control systems (unless your using 35MHz) so take care to make sure your radio link isn't compromised before you fly with one of these on board.

There was an artical about making your own tuned pipes in aeromodeller in the 70's. I made one for a G20/15. Two cones rolled from thin aluminium sheet and glued along the seams with high temperature epoxy - it worked well. When I was prototyping the design I used cardboard with a coat of fuel proofer. It lasted long enough for bench runs to test the design.

I'm curious, why did you chose to stop using mode 1?

Hello Ady, Thanks for the info. It looks like the stuff I ordered on fleabay might be a bit thin then (5 momme ~ 20g/m^2), still should be usable for freeflight and quite reasonable at £4/m http://www.silkcraft.co.uk. Back when I was flying control-line I always covered with the nylon wet which seems to be what some also recommend for silk so I'll probably try that first. Steve.

Hi Ady, The Javahawk looks very nice. Do you happen to know what weight of silk ( g/m^2 or momee) you used for the covering? I'm thinking about doing something WWI and silk should look about scale for linen. Regards, Steve.

Following a truly underwhelming response on here I had another go at stripping the Keller. After removing the screws all that was required were a few light taps with a wooden mallet on the end of the motor shaft to dislodge the back plate. After cleaning out the accumulated dust from the brushes and putting a little oil onto the bearings everthing seems to be turning smoothly again so I might get away without replacing the bearings.  Steve.

I have a brushed Robbe Keller KE 22/9 that needs some attention, bearings, and possibly brushes. I have removed the three small counter sunk screws that secure the backplate but I cannot get it to budge. Is there anyone on here who has taken one of these Keller motors apart and can offer any advice? If I cannot refurbish the Keller I am going to need a replacement. The motor is a snug fit in the nose of a 2m glider so a direct drive brushless inrunner would be favourite, however the maximum motor diameter that will fit without major surgery is 35.5mm. Does anyone know of a brushless inrunner with an o.d. of less than 35.5mm preferably with a 5mm dia. shaft with an output power of around 100-150W and rpm/volt of 900-1200?  I thought I had found one (Black Mantis BM3550-900Kv) but Giant Cod very kindly measured one for me and it turns out these are actually 36mm o.d.  Steve.

Steve W-O Sorry, I did have a look at the KK multicopter board but for the sort of thing I'm really interested in it seemed a bit big. It might be a good way to try some experiments though. Any idea what one weighs ? Something that also concerned me a little was the Murata gyros on the SMD version of the KK as these are prone to beat frequency oscillation problems unless the frequency of all the gyros are sufficiently separated. Murata only make two different versions so at least two will always have frequencies that are close. The problem manifests itself as a large amplitude low frequency oscillation at the gyro output which is very difficult / impossible to remove.  And a heads up I noticed a warning on http://www.kkmulticopter.com/ that some of the boards being sold on e-bay are rejects that have failed QC.  ErfolgThere is a similar video for the UMX Beast biplane with a "with and without gyro" sequence, it could have been staged but there appeared to be a noticable difference. I had a Veron Tru-Flite kit of a Cosmic Wind (about 16" span from memory) when I was a lad that I always fancied putting r/c into, not possible then but it might be possible now, and I suspect I will need all the electronic aids I can get in that one.  Having looked at the GeeBee video again I'm wondering if they may be doing something more sophisticated with their controller than simply using the gyros as a damper.

Seeing the GeeBee also sparked my interest in using gyros to tame otherwise difficult / impossible models. Have you see the video of it flying? It looks mighty impressive for a 20" span model of an unstable aircraft (particularly in yaw according to Benjamin's book) but with scale tail surfaces. So far I've not found any off the shelf 3-axis gyro systems for aircraft so I've started looking at what could be "home brewed". There are several inexpensive 3-axis mems gyro chips available which I assume come from the game / smart phone / tablet market which might be suitable at about £10-£20 each. I haven't had a good look at the specs yet but one of those along side a simple microcontroller such as a PIC might be all thats required for three axis damping.

For light weight electrics and free flight models I use WHSmiths non-stick covering film (meant for covering books). Which in spite of its name sticks quite nicely with r/c modellers glue. The film comes in a 5m roll for a few quid. To fit I cut it to shape and hold it in place with masking tape and then apply a narrow bead of the glue spanning the edge of the glazing and the airframe.