S-l-o-w flying KF delta build
The objective is to build a foamy that I can literally throw in the car without worrying about breaking a prop or rudder, and that can be built from el cheapo materials and spares I have lying around.
For the material I'm using a combination of foam core art board and 3mm depron. I was surprised that I couldn't find something suitable at Bunnings after reading all the rcgroups.com posts from the US about the materials available from the local hardware giant.
Here's step 1. Outline on the 5mm foamcore artboard. This stuff is a layer of foam sandwiched by two layers of cardboard. Looks quite strong and light so it should do the trick.
How to fix the E-Flite Tensor 4D foamy bipe
So I flew the Tensor in a bit of wind, it got a bit far downwind from me and I put it in :(. Broke the fuse clean in half. Such a disappointment after enjoying how well it flies. So how to fix it? Well it's taken me a while but I've discovered the world of the hot glue gun.
I've read about the dangers of hot glue guns melting the foam but also the benefits that if done right, the foam cam slightly melt creating a better bond. So here's the repair job, looks pretty good however its yet to be tested in flight. I expect with most repairs, if its going to break, it'll break somewhere else other than the glue joint. We'll see....
VMAA Trophy 2010
The VMAA trophy was held at the state field, Darraweit Guim outside Wallan. It's a two day event open to all clubs in the VMAA. This video shows a few short clips I grabbed between flying and calling for others. Towards the end of this video is some keychain cam video from my Precedent Fun-Fly. I mounted it with velcro and cable ties, vertically on the rudder and rotated the video in software.
Flying Lawn Mower at Warracknabeal
The annual Warracknabeal vintage machinery easter weekend show is on again and while there's tractors as far as the eye can see, every hour on the hour a high pitched buzz can be heard from over the back of the display grounds. Look up and you might be surprised to see what looks like a Victa lawn mower getting about the sky. The contraption is aptly named the 'Cloud Clipper' and was built by Peter, a member of the Warracknabeal Model Aircraft Club.
By the way, if you are one of those who were thinking that we will be talking about a mower that operates so fast it breaks the sound barrier, then we apologize for the confusion. Go check out BestofMachinery for that, they review only the best makers of lawn mowers which you can get on great discounts - they might just have the thing you are looking for.
Peter says the plans came originally from a magazine out of the US. It's a full foam core wing and he had to build a hotwire foam cutter and learn how to use it just for this plane. It has elevons and no rudder. Peter's advice is to keep the nose up and into the wind on landing otherwise it won't be a pretty return to earth. The foam construction has held up well to a few hard landings and the model looks in great shape. Unfortunately the wind picked up today and the model tipped over on the ground, breaking one of the wheels. I hate damaging a model with a hard landing or an outright crash but wind tipping them on the ground! Don't ya hate it.
E Sky LCD Voltage Indicator
Ok so I've got an idea of how much current the receiver battery monitor draws (about 10mA) but what about the voltage. What does a green light really mean. Can I rely on a simple green or red LED to base my decision on?
I hooked up an E Sky LCD Voltage Indicator in parallel with the Tower Pro monitor to define the actual voltage levels represented by each LED. Keep in mind the battery pack used is a four cell, 4.8V 1100mA Sanyo pack.
According to the Tower Pro thresholds then, a pack is in good condition only when the measured voltage is greater than the defined voltage (4.8V).
IMAC @ LVMAC, Lake Narracan
A few photos from the IMAC comp at LVMAC today. A bit of wind coming off the Lake kept everyone on their toes.
[gmap]
SC Models – Foamy Profile EDGE 540 build
With a model this simple, it's hard to find much to talk about for the build. Everything has gone together quite easily until tonight. Looking at the role of hinging tape that came with the kit I thought it looked a bit light on. I haven't wasted any but I gues I've used too much on the spars that run the length of the wing. Tonight I got to hinging the horizontal stab and I only got one quarter of it hinged before I ran out of tape. Easy, I thought with all this other tape I've got lying around I'll just make do but I don't have any suitable tape thats clear. I can't bring myself to use some ugly brown tape on my new foamy!
On the topic of foamies, check out this video of an indestructo foamy, the SupaFly...
SC Models – Foamy Profile EDGE 540 build
This kit is from SC Models and can be seen on the web here http://www.scmodels.com.au/electric-planes/sc-e540/index.html
First impressions. Well for $43 delivered I guess my expectations are enough bits of foam, wood and bits to put together a little foam Edge 540. I'll need to supply prop, motor, ESC, servos, battery and receiver (all of which I have leftover from a previous model).
On removing the contents from the box, one of the wheel pants was broken in half. A bit of glue should quickly fix that. Also when I compare the parts in the box to that shown on the photo on the outside of the box, I seem to be missing one carbon fibre spar. There are two in the box (one round and one flat) but there are three in the photo. *****UPDATE - I'm not missing a spar. The photo on the box shows a dark leading edge on the wing that I had mistaken for a carbon spar***** I've left the instruction manual at work over the weekend so I can't check with the manual till Monday. This is one of the reasons I reckon all suppliers of kits should supply manuals in PDF format on the web which can be edited with software as sodapdf online. Another foam model I bought second hand almost came to grief because the CoG was way out until I downloaded the manual from the net and moved the balance further forward. I'd always wondered what it'd be like to fly a model with the CoG way back behind the recommended and let's just say it was.... difficult.
Other than that, the kit looks good. I don't imagine the build process will be very long or complicated and the flying side of things will be much more interesting to discuss. So, check back when I've found the manual and started the build for more details.
How much current does a receiver battery monitor draw?
For all the years I've been flying RC my method for making sure my batteries are charged is to put em on the charger overnight before I go flying the next morning. Touchwood this has served me well and I don't believe I've ever lost a plan to flat batteries. I've never monitored the state of my receiver batteries throughout the day though. How many flights are they good for? 5, 10, 15? For me, I never seem to get a full day of flying, maybe 5 or 6 flights at the most and the receiver packs hold up fine but it still left me wondering, how many electrons are left in the tank after those flights.
I saw some cheapy battery monitors on ebay and thought I'd try one out. The two I bought didn't actually state the current draw but identical looking versions were touting 5 mA. I was keen to put them to the test.
Test 1: Current draw of just the battery monitor. 10mA.
A 4.8 volt, 1100mA NiCd battery is connected directly to the battery monitor with a multimeter in line. The monitor shows a reading second from the top in the "Perfect" range.
Test 2: A JR RS70 36Mhz synthesised receiver. 24.7mA.
Test 3: Futaba 36MHz crystal Receiver. 15.2mA.
Test 4: JR Rx & Voltage monitor. 40.1mA.
I expected a little lower at 10 + 24.7 = 34.7mA.
Test 5: JR Rx, Voltage Monitor & 1 micro servo. 45.2mA
Test 6: JR Rx, Voltage Monitor & 2 micro servos. 52.2mA
Test 7: JR Rx, Voltage Monitor & 3 micro servos. 57.8mA
Test 8: JR Rx, Voltage Monitor & 4 micro servos. 63mA
