Here is a list of all the postings Trevor Crook has made in our forums. Click on a thread name to jump to the thread.
|Thread: Electric/35mhz compatability|
Useful info, Frank - not too far from my guesstimate.
Ally, Frank has made a good point on the Lipo size - if your fuselage can take a bigger pack, it will give you extra flight time, without too much of a weight or cost penalty.
Something I forgot to mention is that the ESC will automatically cut power to the motor when the Lipo gets low, but still power the radio, so you'll still be safe to glide in and land. It's best to time your flight to avoid this, though, which you'll be able to do once you are familiar with the flight time you get for a given battery drain.
For some reason I didn't see the photo!
For that weight, a sub-100W setup should be fine. You can get cheap outrunners known as "bell" motors (because the case looks like a bicycle bell) and one of these should be fine. The prop will be bigger than the Cox one, as it won't be revving as high. So I'll revise the setup to:
Brushless bell motor, 10-12A continuous rating
1000mAH - 1300mAH 3s Lipo
The ESC contains something called a Voltage Regulator, that takes in the Lipo voltage and converts it to 5V for its own electronics and the receiver and servos. You just plug the ESC into the throttle channel, and it feeds the 5V down two of the three wires going to the Rx socket. Hence, nothing is plugged into the Rx battery connector.
Nearly forgot, whichever motor you get, you'll need an appropriate prop adaptor.
With this set-up, try a 7 x 4 or 8 x 4 prop - it will depend on the motor's kV.
Ally, welcome to the initially befuddling world of electric flight!
You don't say how big your glider is, but a power set-up of 50 - 70 watts per pound of weight will be about right. So let's assume your glider weighs 2lb, you'll want a 100-150 watt setup.
A 3-cell lipo should be ok, and makes the sums easy, as you can approximate the voltage to 10V. 10V x 10A will give 100W. I'd recommend going for 150W, which would require 15A. You'll want a 20A ESC to avoid stressing things, and a motor that will deliver 15A continuously (you won't be on full throttle much, so this should be fine). The ESC powers itself and the radio gear from the lipo, you won't need an Rx battery.
If you choose a motor that gives 1000-1200 revs/volt (expressed as kV) this should give a sensible prop size of, say, 9 x 4. Unfortunately, the only way to check the current and power is with a wattmeter, which will cost you around £30. Most distributers quote suitable prop sizes for their motors.
You should be able to get a well specced lipo charger for around £30.
I seem to have gone on a bit, so I'll summarise my guesstimated setup:
15A 1000kV brushless outrunner
20A brushless ESC
1500mAH 3s Lipo (20C discharge will be adequate)
Online suppliers will have the keenest prices, but as you'll probably need some help, try another shop if you can. Alternatively, specialists like West London Models wouls be able to advise and supply by phone.
|Thread: The cheapest radio 2.4 GHz|
One of the clubs I'm in forbids non-CE marked equipment and 2.4GHz receivers that are a different make to the Tx/Tx module. Spektrum and JR can be mixed.
I think there have been some issues with "Orange" receivers and they are worried about the BMFA insurers not covering equipment approved for use in the UK.
Wise advice, Paul, but Major may be seriously strapped for cash, and may not want to go beyond the Sharkface for now. The Planet solution seems a good one - UK distributor with backup, CE marked etc. I've bought loads of servos, escs, motors and batteries from GC with very few problems, but I get the impression that the backup wouldn't be the same on the RC link as you'd get from a major player.
The 35MHz suggestion is a good one, but as Steve said, 2.4 is more electric friendly, and the aerial easier to hide in the little Sharkface.
|Thread: Which Radio Would You Buy.....?|
Not sure if anyone has mentioned this yet, but a feature that (I think) is unique to Spektrum/JR DSM2 and Spektrum DSMX is Modelmatch, which prevents you from using the wrong model memory - a potential model saver. Spektrum also gives ready access to the large range of BNF models, if that's your interest. End of sales pitch from Spektrum user!
In our club, most makes are used, with very few problems from any. Multiplex are the only ones to put the Tx display in a sensible place, and have very intuitive programming. As advised throughout this thread, best to get the feel of your shortlist before buying. It's also worth seeing what your friends/fellow club fliers use - if you buy the same there will be plenty of experience and advice available.
|Something that I don't think has been mentioned is the compatibility between older and newer technology from the same brand. Futaba used to be all FASST, but their low-end systems have started to use a new system with cheaper Rxs, and the two are not compatible. According to the RCM&E review, this FHSS system will be the norm on everything with less than 8 channels, the more expensive sets having FASST. Similarly JR are moving away from the Spektrum based DSM2 to their own (non-compatible) system. Spektrum have been very clever, and have improved their original DSM2 with DSMX, with forward and backward compatibility.|
|Thread: Flying Facing the Sun!|
|Ski goggles - that's worth trying, I'll try to borrow some to see if they work. As you say, who cares about the look as we're a sartorially challenged breed anyway!|
I sympathise with your sun problem, our club has a south facing flight line which we can't do much about. Your situation is slightly different, however. As a committee member for our club, I'll say that the club should be run by the membership, not the committee. If enough people share your opinion, table a proposal at your next AGM that the club moves the pilot area, if possible. During the ensuing debate, it may become clear why it is where it is - as someone said above, there may be a good reason. If there isn't, it can be put to the vote, and the members can decide.
|Thread: Galaxy Magician builders|
|Yes, the Bullet is on my "to do" list - unlike the Magician I never had one in my glow days, and it's another candidate for a sleek electric nose. I don't think a 3s setup will be enough for that one, though.|
Re. the c of g, my electric version is a bit nose heavy, too - it won't spin. I've added a little lead to the tail, but not enough, so I'll try some more. It's one of the reasons I haven't tried re-propping it for a 4s battery yet. If I was building it again I'd obviously engineer the battary bay to be further back.
No need to apologise for not liking the mod, Lee - we've all got different tastes, and that rearward canopy does give the model a unique look. In fact, people have said my version looks like a taildragger Gangster. I like it though, and I tell myself it must improve the knife-edge!
As for how it was done Andrew, I just made a new half former to sit at the back of the revised cockpit position, reduced the length of the forward top decking, and made new rear decking from material I had to hand. The cockpit moulding is flexible enough to fit the slightly wider top deck. The undercarriage mod is fairly obvious from the photo, the wire goes up into drilled blocks glued to the sides and former. This mod is well worth doing.
|Thread: SE5a I/C to electric|
Here are some pics of mine:
|Thread: Galaxy Magician builders|
Thanks, Tim. I think I worked it out when I clicked on the "Album" tab. Let's try:
This shows the cockpit moved forward
Right, I'll try my first post with attachments!
Ah, it seems I need to create an album somehow. I'll find out how to do that, then try again.
|Sorry guys that asked for piccies of mine - only just looked at this thread again. Haven't any phots yet but I'll take sone and post them.|
|Thread: SE5a I/C to electric|
Mine has a modest 400W setup, and flies as well as one I had 20-odd years ago with an OS40 4-stroke. The motor is a 900kV unit (E-Max I think) from Giant Cod, rated at 50A and turning a 11x7 prop. I've used a cheapie GC ESC rated at 60A, with a NiMH for the radio in case this smokes - it was only about £12! No problems so far though. Lipo, again from GC is a 3s 3000mAh Loong Max Tipple.
Performance with this set-up is very scale, ample for easy take-offs and half throttle cruising gives an easy 10 minute duration. We often over-power our models, but this aircraft just wouldn't look right flying like a Pitts!
|Thread: Galaxy Magician builders|
Just found this thread! I had a Magician 20-odd years ago and it was a great flier. I decided I fancied a kit after lots of ARTFs so bought another last year. I modded it in the same way as the first one, as follows: the U/C design is rubbish so I glued in a piece of grooved U/C block in the appropriate place, and fitted two torsion bar legs, ie they come up to the fus at the normal angle, then cross it and go up through 90 degrees into blocks. The other mod was to move the cockpit forward using extra balsa decking - I prefer the look.
As I'm all electric now, I fitted a 3s 400W setup, which gives it adequate performance without being ballistic. The battery bay will take a 4s if I want more. It flies a treat and has no vices. With the electric motor the nose is much sleeker, and the ABS cowl is not an issue. It's covered in two colours of Oracover/Profilm.
Highly recommended, but as the RCME review says, the plan and instructions are pretty dire!
|Thread: Fleet RC|
I worked part-time for Derek over a long period, but don't know what the situation with the business is since he and Ernie retired and sold it on. It must be very difficult to compete with the far-eastern labour costs, and the economies of scale from a world-wide market, which Fleet never really had.
I still use much of the Fleet gear I still have, and have always found it as reliable as any other. The Omega set gave 10 model memories when the equivalent Futaba FF6 only had 4. The PCM failsafe is also much easier to use than on the FF7, which I also have - the transmitter has a failsafe button which you press while holding the controls as you want them. This is safe and easy while flying. The receiver then remembers that setting. The Futaba failsafe can only be set up on the ground. The FF7 does a lot more, though.
Sadly Derek died last year, and we lost one of British R/Cs true pioneers, who stayed in business longer than any other UK manufacturer.
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