David Hall 9

This year, I plan to get a couple of my 2m RES kits built, to have a go in the comps that have been organised for 2022. The kits I have are the RES Eagle and the Kavan RESCO (similar to the Circle Dancer). These have a single spoiler. I have a few servos in hand that I would like to use. These are the Blue Arrow D05010MG 6g servos that can produce 1.2Kgcm (but they look quite small). How much torque does the spoiler servo need?

That's a useful product! I might try a sample. For this time, some 02.mm CF is winging its way to me, so I will use this on the larger repair.

I am thinking about how I might repair the damage to a couple of my moulded glider wings. Filling the hole and covering with resin and CF/GF cloth seems to be the standard way to do this. One of the repairs is to a 250mm length of LE back to the spar. It's a hollow construction and has an area where the skin is delaminated from its backing (lots of fiddly work to do). I found some CF sheet material in 0.2mm thickness and wondered if that might be easy to "plate" the open area. I can stand the extra weight and the ease of application and finish are attractive. I can construct a leading edge strip, bridging the gap, and apply the sheets as a top sheet and a bottom sheet, but the preferred option would be to use a sheet which has been pre-bent to the shape of the leading edge. Is there way to mould a cured CF/resin sheet around such a sharp radius (maybe only 3mm)? (I'm thinking woven mat, probably 3K at 200gsm).

Thanks for the info... It occurred to me that, if I use a sheet of (prepared) acetate as the external surface that will give the CF/GF wetted fabric it's shape and finish, might I be better applying the resin and fabric to the sheet, then holding the loaded sheet in place on the wing until set. That would give it a smoother finish?

Thanks for the pointers, I'll go with that.

I have to repair a couple of my moldie F5J gliders, each with damage to the leading edge, with a chunk missing back to the spar. Fortunately, the structure is still sound enough, so I simply need to fill and the skin the wings (one is glass fibre, the other is carbon fibre skinned. For the point at which the wing repair is skinned, I have previously applied CF/GF cloth and sanded down the lumps later. This time, I plan to apply a plastic sheet to the wet cloth and hold in place/shape to give the cured cloth a smooth finish. Can anyone recommend a suitable treatment for the plastic (Acetate/PVC) sheet to release the cured resin? .. Recent efforts with furniture polish have only been partially successful with many specs still stuck the the sheet when removed.

Does anyone know if it's likely that this series of comps will run this year? The dates are booked for the use of the BMFA national venue.

Out of curiosity, I collected together a selection of LEDs. The normal LEDs will not give any light at 1.3v. There are plenty of small bulbs that work off 1.5v, any of these would work, as would the small LED insert from one of those small LED torches that work off a single 1.5v battery.

As an alternative, you could use a pair of AAA cells and another glow clip to just check for a non-blown plug element. (glow clip, LED, series resistor, batteries). Better still, use a 3v lithium coin cell, it can be nice and small then.

Back when we used a 2v lead acid cell for the glow plug, I used a reed relay and an LED to indicate when power was flowing through the glow plug. The LED was mounted in the plastic clip, so it was easily visible as I connected it. It uses a reed relay removed from the plastic body of a door/window alarm magnetic contact (easily available and cheap) with a few turns of wire around the glass relay (see image). I guess that if you use a small LED, it may still visibly indicate with a low voltage battery. You can use fairly heavy wire for the windings (only around 6) so you may not lose too much in the extra wire.

I discharge my 3s LiPo's into a bank of car headlamp bulbs at up to 25A DC, controlling the output current by using a brushed 30A ESC. It works a treat from barely on to full power. I guess that a similar setup would lend itself well to your application on the DC side. A brushed (non-sensored) ESC is pretty much a simple variable pulse width output device. ( I should add that this setup will attempt to provide pulses at full power but of a shorter duration, so not so good for discharging batteries that can't accommodate the full output current. For smaller batteries the load is reduced, reducing the pulse current.)

There are plenty of cheap and surprisingly functional alarms out there. I have one that is armed/disarmed via a keyfob. If it detects entry it can send texts and phone numbers as configured. My daughter recently fitted a front door CCTV system that pings her phone if movement is detected near the door and provides a video on her smart phone. A combination of the two would give some peace of mind. ....... although mine phoned me whilst I was on holiday on Tenerife, so some plan to have local help is required.

Modern switching devices have become very efficient. There are 70A BLHELI_32 ESCs (without BEC) installed in some of my e-gliders that have no heatsinks. They are pushed to 50A working for 30 secs, then very little. They don't even get warm. I think that the heatsink is as much for the BEC, particularly linear BECs.

Interesting thread... I'd like to ask about something that confuses me: I often see posts in which the poster claims to have "scratch built" an airframe using plans or even a short kit. I'm sure that, years ago, a scratch built aircraft was an own design, so, no plans or kit. Did this change?

for info..... London Bridge;

Does your club have a rule which prohibits beginners/learners (anyone without an "A" certificate or equivalent) flying alone or without an A/B cert holder being present/supervising? If so, what is the role of the cert holder?

I hadn't considered height layering of area restrictions. This goes a long way towards helping me to understand what these maps mean. Thanks for the input.

Thanks for the info, John Lee. I wonder why it is shown as "flying drones here is not recommended"? Perhaps it's overly cautious. One statement from the app says.... "this piece of airspace is in effect between Surface and 3500ft MSL" so, I'm guessing that the restrictions mentioned in the app do not apply to heights over 3500ft which must be prohibited to any non-controlled traffic?

That seems to be the case, clicking on the area shows upper and lower limits as FL660 and FL150, so above 15000ft and below 66000ft. This app may not be intended purely for "our" UAVs.

Yes, I get that there will be many military activites in the greater area, but is it permanently illegal to fly models there without permission? Why would that be shown as a prohibited area on that app and yet not on the Drone assist app (to name one, there may be others)?

A couple of years ago, I used the app "Drone AssistUK" to find a safe and legal place to fly my small model plane whilst giving a few lessons to my son during my visit to him in Argyll. It allowed us to find a suitable place outside of the prohibited zone surrounding an airport. Recently, I wanted to check on an area that my local model flying club is about to use as a regular flying site. I understand from the club committee that the area is in class "G" airspace and so is good for us to use. To my surprise, when the Drone Assist app was consulted, it shows a huge area of pink/red that it seems to list as "Regulated airspace" with a recommendation that drones are not operated within. (See attached screenshot). There are many model flying club sites within this area. Are they operating against the recommendation of NATS? But all may not be as it seems. The website " dronesafe.uk" shows what appears to be a simpler map which shows areas in which model flying is prohibited. Quite sensibly, and as expected it shows airports and airfields. The map page includes a simple and stark warning "It is illegal to fly any drone at any time within these airspace restrictions, unless you have permission from the aerodrome, air traffic control unit or whichever agency is responsible for issuing permission. More details can be found by clicking each restriction." This appears to be fairly straightforward, but... look at the area of the coast of Yorkshire which appears in red (amongst others). This is not shown on the Drone Assist app. It may be that my quadcopter flight on the Yorkshire coast was illegal, unless I claim that I used the Drone Assist map... but then ignorance is no defence. I've tried to understand this, but am failing miserably.... can anyone explain how to interpret these maps/instructions?

Posted by Mick Cass on 03/02/2021 18:55:45: I use TalkTalk, and the call blocker is simple to use, but quite a few of the scammers use multiple numbers, and you may have to block several numbers to stop the calls. We seem to have different Talk Talk call blockers. The version available to me is one that invites new callers to leave a short message (Hi it's Fred from the shop...etc) which is then played to the user, then allowing the user to accept the call this time only, reject the call or accept and add to the caller to the accepted list (they then get right through when they dial). I never have to manage phone numbers. Most that call never take the time to leave the message/introduction (barr one call from IPSOS), and likely would be blocked anyway...it's not worth their time, I guess.

Me too, I've been with Talktalk (previously Tiscali) for many years. The call blocker is simple and works well. It stopped our cold calls dead..   Edited By David Hall 9 on 03/02/2021 18:52:21 Edited By David Hall 9 on 03/02/2021 18:52:32

My RES Dart kit build is going well. One wing basic build is complete. Just looking ahead to fitting the various surfaces, the spoiler is 35x190mm and the material given in the kit is medium 1.5mm balsa sheet. Is this suitable? Seems a bit light....     Edited By David Hall 9 on 28/01/2021 17:12:01

Pleased to hear that you recovered from the swine flu. At the moment, we (wife & I) are trying to stay well away from all others. The realisation that, if we were to fall ill and need hospitalisation, they may not be able to help due to being overrun is scary. Whilst being confined to home, the thought crossed my mind that life is short and we should do the best with it whilst we have it... to that end, I figured that I might buy the very expensive moulded carbon fibre competition glider that I have so desired. But.. there is a chance that I might not survive to a post vaccinated world, so it will have to wait a little longer... Waiting for my vaccine too.