Here is a list of all the postings Martin Harris has made in our forums. Click on a thread name to jump to the thread.
|Thread: Futaba servos.|
I wonder if it was genuine? Futaba wiring is normally well supported.
I was interested to find that one of my 3001s was a fake when I was looking out some servos for a recent model. I hadn't heard of 3001s being counterfeited (unlike 3003/4s) but suspicions were raised by slightly fuzzy printing. The case screws were very coarse helix type, there were many internal differences and the clincher was the lack of a ball race on the output arm!
|Thread: Interesting reply from email to Richard Moriarty, CAA|
Yes...and in case anyone's confused, I was posting it while you were reminding me!
Another interesting point is that these proposals may not be set in stone and the situation may change in a year or so - whether for better or worse is not specified!
The EASA regulation on drones, which contains some specific provisions for model aircraft associations, is expected to be published in final form shortly and will start to come into force sometime during 2020. Once that regulation is in force in the UK we would then expect to review and, where necessary, align the UK approach with that EASA regulation. At present, however, we are working towards a DRES system that aligns with UK law and policy.
Hopefully this posting will be in order - David did say that "anyone can start a new thread in the light of new developments".
I received what seems to be a generic reply but interestingly it does state that in addition to continuing talks with the organisations, the CAA are considering the possibility of "model aircraft associations or clubs as operators: model aircraft associations or clubs would have the option of registering as the operator with their members acting as remote pilots. In this scenario, the association or club would need to meet any legal requirements and take accountability and responsibility for the actions of their members, and members would need to abide by the remote pilot requirements."
Quite how this would affect the funding model if 40,000 or more operators registered under the 4 major organisations is not mentioned but I think it suggests that the CAA are taking some notice of comments made to them and aren't necessarily the bad guys in this situation.
|Thread: Glitches and crashes|
Any idea what happens at that time that's so different to the rest of the day?
I see there are a couple of aerial towers close by with microwave dishes on one. Funnily enough, we have a similar tower near our field and a few members swear blind that their models are regularly affected in certain areas. Oddly, many others have flown in those areas extensively without incident...
Edited By Martin Harris on 21/05/2019 23:38:02
|Thread: Zenoah 38 conundrum|
If you use it correctly!
Yes, no and eventually (I hope) yes...
I took it flying a couple of weeks ago and although it started easily and produced decent power, all was not entirely well. The engine kept appearing to go rich and take extended periods to clear on throttling up during flight. Over the duration of the flight, the idle increased such that it was too high to land and after several circuits and eventually running out of throttle trim, I had to cut the engine as I came over the hedge.
On dismantling the model, I noticed that I'd used far more fuel than expected and there were black wet deposits where the model had remained almost spotless in the past. I concluded that there must be something wildly wrong with the carburettor, backed up the low end needle ending up completely closed.
Having invested in a needle valve setting gauge during my investigations and carefully following the Walbro instructions to use it to set the arm so the needle valve was just opening with the gauge contacting the operating arm, I knew it wasn't the adjustment at fault and I'd also tried a new needle as well in case it wasn't seating properly. I'd almost resigned myself to buying a new Walbro carb but hadn't got round to trying a Chinese knock off that I'd bought for not a lot a while back which was not going to be easy to modify for throttle linkage and a couple of other awkward factors.
A couple of nights ago, I was browsing the 'net and happened upon an official Walbro video of setting the needle valve. When I watched it, the penny dropped...their definition of the needle valve opening was not when it started lifting off the seat but when the operating arm started moving...
Having whipped the carb off, I opened it up this morning and checked - there was probably an 1/8 of an inch difference from the initial movement of the lever until the valve started to operate! No wonder the bottom end was running rich...
So, needles set at the recommended 1 1/4 turns out, the engine leapt into life and with a 1/4 turn richer on the low end and a smidgeon on the high needle was starting, idling, transitioning and running at full power beautifully. As I had some urgent test flying to do with my 1/4 scale Cub this afternoon there wasn't room to pop it in the car for a proving flight but I'm as confident as possible that there's every chance that with the gasket problem having caused the pumping problem and the needle valve now operating correctly, there's no reason not to expect success.
|Thread: Another thread closed|
Sorry, but I find some of the comments here rather contrary to my experience of the forum.
This forum is generally well moderated, friendly and above all, a wealth of information and help. I've had robust discussions with the mods on a couple of occasions over the years - usually when I've had issues with some of their decisions affecting other contributors - but I've had full disclosure of some reasons for seemingly unfair decisions and we've always reached some sort of common ground.
Are the mods over zealous? No, not in my opinion - this is a forum that you could point your chlldren/grandchildren to and although I'm no prude in the right company, it's refreshing that due to the policies here, discussions rarely descend to bad taste or pettiness.
|Thread: New, need help|
Hi Matthew - welcome to the forum.
Can I assume from the questions you're asking that you're new to model flying? If so, best bet is to contact a local club or two and see if they will be happy to help you (I know ours would) but if you haven't done a reasonable amount of RC flying, you will need to learn on something a bit less complex - although a well sorted Lancaster should be relatively easy to fly, trying to learn on one is courting disaster and the inevitable bumps and bruises along the way will wreck the model before you have a chance to do it justice.
Meanwhile, in case you're at a good standard, perhaps some details of the model would assist in identifying it - maker, wingspan etc...
|Thread: Trouble contacting Laser engines|
Hope all goes well and best wishes to you and your family.
|Thread: Poll for who intends to register.|
For the avoidance of doubt, I have no issue with those intending not to register until they wish to fly as a (probably meaningless) protest and I will do all I can to back the BMFA in its campaign against this unreasonable (and as things stand, potentially extortionate) proposed charge.
I still stand by the assertion that advocating law breaking is counter-productive to this process. We should explore all legitimate avenues before throwing our toys out of the pram, going boating or taking up knitting...
Threatening to flout the law could be interpreted as being much the same as the irresponsible faction that have brought about the excuse for this legislation. The commercial interests driving the process would love to see us painted in the same light.
|Thread: New Model Servo/Trim setup|
If it's any help Charlie, I've built and set up countless models over the years and have never owned, or used, a servo tester. The advice to set up the servos mechanically as far as possible is extremely sound - when I started there were no adjustments - not even reversing and certainly no travel adjustments - available from the transmitter so you learnt this skill, which maximises mechanical advantage and servo resolution, from the outset.
I've seen too many poorly thought out installations since returning to the hobby - these are largely due to the ability to drop servos into a model and use the programming to correct poor practice - you seem to be more aware than most beginners!
Edited By Martin Harris on 17/05/2019 22:16:16
|Thread: Poll for who intends to register.|
I shall be flying and shan't be voting in any poll. Like John, I shall wait to see what is resolved. We need to support the BMFA in their dealings with the CAA and government departments and theatening to ignore legal requirements can't be helpful to them.
|Thread: Suggestions for vintage model|
Ah - the Lumpers...my first (successsful) trainer back in the mid 70s.
So tough (nylon covered) that the wings simply rattled more after each impact into Croxley Moor. I wonder if an OS 20 four stroke would overpower one...rudder/throttle only (plus test glides and proper trimming) would be fun to experience again...bit of CF across the centre section perhaps to counter the extra loading...hmmm
Edited By Martin Harris on 17/05/2019 17:22:39
|Thread: Revolver 46 with Saito FG 14|
Things running out of true - back plate distortion, holes drilled off centre, grit under the prop boss, badly moulded prop etc. etc.
I'm assuming you've checked prop (and spinner) balance and run-out issues?
The first thing I'd do beyond this (and as a general practice) is to fit those wings. It's very common for an airframe to vibrate - sometimes to the point of being damaged - if run without the wings, which have both damping and stiffening effects.
Your servos and receiver may well have been affected by the loose plug cap - it's imperative that the plug cap is firmly connected and running with it loose (or attempting to start the engine with it disconnected) can cause failure of the CDI unit. The arcing resulting from a loose cap can cause massive interference/glitching issues.
Edited By Martin Harris on 16/05/2019 23:59:17
|Thread: CAA registration consulation|
I think that some people may be losing sight of the potential cost of registration. I believe there's general agreement that the potential number of registrants is a fraction of the official estimate of 170,000
Therefore quoting the £16.50 fee is at best hopeful and more likely to engender apathy in the less committed aeromodellers, whilst diluting any case we make to the Government (the CAA have had clear directions to self fund this) and individual MPs.
I'd certainly agree that advocating deliberately flouting the law is no way to gain trust with the authorities - WE need to be seen the responsible and law abiding injured parties in this knee jerk reaction to the antics of some drone flyers and a few conventional model flyers stupid enough to provoke such action.
Edited By Martin Harris on 16/05/2019 13:17:29
|Thread: Twin ic throttle mixing|
One of your clubmates did the same on his hand launched Mosquito and was quite happy with the results.
Reading some of the posts above does raise some thoughts though. Mention was made of the effects of over complication and its just possible that I might have suffered from just that with my throttle mixes. It could explain an unfortunate incident...
A couple of weeks ago on a very gusty day with a fearsome crosswind, I decided to exercise my superior skills with my Slim Twin and impress my clubmates with my mastery of the air. In hindsight I might have wondered why the Red Kites, who regularly watch our pathetic attempts at aviation with a look of avian disdain, had decided to view my antics from the safety of their roosts in the nearby woods...
I took the precaution of lining up diagonally across the runway into wind, opened the throttle and the model leapt into the air immediately - no real surprise in the strong wind as it is off in a few lengths even with no wind. What was a surprise was the immediate roll to port which failed to respond to aileron. The result was an undignified arrival on one wingtip and a cartwheel.
I put it down to the effects of curlover from a nearby hedge and mishandling at low airspeed but on thinking some more, I'm wondering if I might have left it in No.2 start position. That would have resulted in a yaw to the left as both engines would continue to run with the No.1 (port) engine only idling which combined with an initial roll due to turbulence fits my recollection of
I don't recall finding the switch in that position after picking up the pieces or having suspicions that the port engine was not contributing its fair share during the couple of rather fraught seconds that the flight lasted but it would fit the scenario and perhaps act as a reinforcement of the warnings that with complication comes the greater possibility of making a mistake. I still like the ease of handling during starting (and the positive effects of asymmetric mixes) and will continue to use the various mixes but it highlights the extra awareness that you need.
Starting is where I find the ability to control the engines separately has some particular advantages. I have a 3 position switch which is set to idle starboard, idle port or full control on both.
I start the port one first, check it for full throttle running and then switch control to the starboard engine, locking the port one to idle. I then start and check the starboard engine and then activate both throttles for a full power check. Having the running engine locked at idle means I can manipulate the throttle on the one I'm starting with no sudden surprises!
I can also practice engine outs with the switch selecting either engine to idle.
Having the ability to throttle back an engine can also add to the repertoire of an aerobatic twin...
I'm afraid I don't know whether your transmitter is capable of this level of sophistication.
I balance by ear - but I'm more concerned with reliable operation than getting the RPM to any particular figure and I can't remember the last time my tacho came out of my modelling box.
Edited By Martin Harris on 14/05/2019 16:00:45
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