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Posted by MikeTheCrash | May 10, 2014 @ 02:58 PM | 14,761 Views
Well I finally finished her, she balances a little forward of the recommended CG with 2 x 4000mAh 3s

Can't maiden for a while due to work and rubbsih weather. fingers crossed.

I think it will need a bungee to ensure a good launch
Posted by MikeTheCrash | Apr 18, 2013 @ 02:23 AM | 16,008 Views
After breaking my Foxtech camera switch with static or short circuit (I took the heat shrink off to get the number of the IC ), I tried to use an inferior product from goodluckbuy that didn't work with the 600TVL camera and DOSD as it destroyed the sync.

Two cam switches arrived from foxtech a week after ordering which work really well. Not flown yet, if it works out then next time I crack open the fuse I hope to shorten and tidy the cables, and I also aim to hllow out some of the foam for a bigger battery

I usually tape my fuselages together so I can get back inside when necessary

Not shown on the picture because it's behind the DOSD, a PC connection socket to the outside of the fuse.
Posted by MikeTheCrash | Mar 18, 2013 @ 10:47 AM | 15,900 Views
whoops realised I had wired up the currents sensor backwards meaning I got less current displaying the more I throttled up! Now fixed

Made some balsa pan servo mounts and glued in place. Really dubious about making the camera look through all that plastic but it is the cockpit view I'm after. When the camera looks straight out of the side the image is much clearer. Using a small camera means I can put it up really high so the view isn't blocked by the window frame.

Also today cut slices from the exhaust cone and glued it with diameter reduced from 90 to 78mm. This mod is recommended on the Mirage thread to increase efflux velocity and thus top speed but will probably make launching harder

First job this morning was to make the baffle that was recommended by Jepe Jets (where did they go?) to improve airflow. Made from liteply with a balsa noggin, it weighs 50g. I should have done balsa sheet!!
Posted by MikeTheCrash | Feb 13, 2013 @ 05:01 AM | 15,932 Views
10AWG silicon cable arrived this morning so I can hopefully finish off the wiring assuming I haven't forgotten anything else

here is the schematic for the stripboard power and video distribution.
Posted by MikeTheCrash | Feb 05, 2013 @ 11:34 AM | 15,890 Views
so I hear from Daniel Wee that the 90A current sensor that comes with DOSD will probably be OK for the 6s power system but by this time I already bought the parts, so I carried on anyway

Hall effect sensor for up to 200A wired up, with a power distribution board. The distro board takes 22v in, sends it to the current sensor on DOSD and to the 3A BEC. Then there's a 1.5A 12v regulator that feeds a filter, then the DOSD, camera and VTX. It also distributes video. The VTx and camera leads aren't soldered on yet, this will probably be done in the wing.
Posted by MikeTheCrash | Jan 31, 2013 @ 07:13 AM | 15,805 Views
Time to get on with the Mirage

I spent two days wiring the beast then couldn't get it to balance so I kind of gave up, exasperated.

back on the bench now. here's a pic of the rudder mod I did last time.
Posted by MikeTheCrash | Jul 16, 2011 @ 12:07 PM | 16,888 Views
Bought this plane a long time ago, before FPV happened to me. I wanted to kit it out with retracts, gear doors, door timer, lights etc etc but now it's getting video kit and an OSD!!

Unfortunately the wing got butchered with the retract and door fitting. I put a strip of carbon in, so I hope that the first hard bank doesn't cause the wing to snap.

The wing is nearly finished, servos are in, VTx, GPS and turnstile antenna. Hope the depron panels fit!

The plane will fly on a 6s system powering Wemotec midifan pro and Typhoon motor. Should be around 1200W and better than 1:1 if I can keep it light.
Posted by MikeTheCrash | Jul 16, 2011 @ 11:52 AM | 16,819 Views
Found the camera image to be wobbly, especially noticeable on the HD keychain cam. So I made this one to be less bendy.

I put some hotglue on the top of the mount to make a "saddle" for the velcro that would be the right shape for the camera, and cut down on wobble. wrapping greaseproof paper around the cam stops the glue from sticking to it.

Turns out the hotglue is nice and grippy so the camera will stay on with an elastic band and not use the velcro at all.

Then it turned out that a lot of the slop in the system is from the plastic servo arm being a bit worn/stretched on the metal spline. so I (shame on me) epoxied it on.

next project: 270 degree servo on its way, metal servo arm, fit the voltage regulator...Oh, and build the Mirage...
Posted by MikeTheCrash | Jul 09, 2011 @ 02:44 AM | 17,320 Views
I have put in a turnstile antenna as per IB Crazy's video tutorial. took me a while to realise the two elements were connected to the centre and the screen but it makes sense when you think about it! Shipping from IB Crazy's web shop to the UK was expensive so I bought a load of components took a deep breath and did it myself. Spare parts will be in my shop - maybe antennas too.

I also changed my camera to a board camera and HD keychain, and constructed an aluminium mount to they pan together. Keychain image is a bit wobbly so next project is to build a stronger one with a longer plate for the keychain

Then I'm going to fit a voltage regulator for the camera as the picture starts to fade as the batteries go flat... I seem to run my batteries too low fairly regularly... but there's not much space left in the fuselage
Posted by MikeTheCrash | May 23, 2011 @ 08:00 AM | 17,255 Views
So the Funjet has been having a few problems with the IMU picking up vibration from the prop. I have a new motor and prop and this problem is a new one really. The second APC prop I had on it was vibration-free. I ought to buy a prop balancer but instead, after much fiddling around, I have found the best layout for IMU with foamn damping.

I have inserted a tooth pick parallel to and about an inch from the wing spar. A small chunk of foam is hot-glued accross the toothpick and the wing spar. The IMU, wrapped in a piece of tape to protect it from the glue, is stuck to the foam

Next up is to improve the aerodynamics of the camera mount. I had the cam attached by elastic bands into a "chair" carved into the front of the canopy. This I then upgraded to a 180 Pan servo. But the body of the servo was glued into the top of the canopy and the camera was sticking out into the airstream, which made me unhappy. I have stuck some balsa in the front of the fuse (where I had originally intended to put a pan/tilt as seen on my avatar but never flown) and now the pan servo sits in that. I hope to find an aerosol lid to make this more streamlined one day. I have carved the canopy a bit to let the camera pan freely.

EDIT with this setup and the keychain camera on the nose the FJ is hard to balance with a big battery. I have to squeeze my 2700mAH right up the fuse to the wing spar and it's a tight fit, and the 4300mAh won't work. This may need another re-think. Perhaps if a make a cowl for the camera i may put the keychain on top of it, alternatively swapping the FPV camera for a board camera may do it, my camera is very heavy.
Posted by MikeTheCrash | Jan 05, 2011 @ 11:34 AM | 17,169 Views
A refit after the plane spent 2 months lost on MOD land.

To keep the strains on the cables and connectors to a minimum i have moved the camera to the nose and the Tx to the side

I have a new canopy somewhere...
Posted by MikeTheCrash | Aug 13, 2010 @ 06:22 PM | 17,941 Views
I was asked to show the layout in my Twinstar, so here it is. I should point out I'm no expert, this isn't necessarily the "right" way, it's my way!

The fuselage is held together with masking tape. This makes it easy to get inside if I need to. Masking tape is light and fairly strong and is seems not to leave any residue on the elapor. The camera is normally taped in too for safety. I also have a strip of gaffer tape under the belly for landing.

I need a ball link on the elevator I can detatch, so I don't put any strain on the linkage when the fuse is opened up.

The dragon link antenna has a trailing component under the fuse which should be put in a bendable tube to keep it straight.

I put the servos in holes I made in the fuse, they are screwed onto some chunks of wood I glued in so I can get them out if I want. The servos might have been better glued inside the fuse and I could have re-routed the snakes perhaps and kept it more streamlined

You can see the Inertial Momentum Unit in this picture. it's wedged into one of the snake runs, and I used bits of paper wedged underneath to get it as flat and tight as I could before taping it in.

ESCs are wedged into the elapor. Bigger than I needed but they were cheap!

Motors take up to 16a - that's all the specs I can remember.

The CoG is correct with the battery nearly all the way forward into the nose. This leaves space under the wing for another battery one day if I want to, but I don't know...Continue Reading