Martin Harris - Moderator

In that case, the radio will see it as a carbon fus....

And Dave Platt?

Danny, getting back to the oiginal topic, don't forget the safety aspect.  I've used my lathe and other machine tools on and off for decades and I'm totally immune to damaging myself because nasty things happen to other people...   ...at least that was until this year.  I should have been warned when a slip of the hand during the summer ended up with me having 4 stitches in a gashed knuckle from hitting a tool mounted in the toolpost but being invulnerable I obviously didn't take heed enough and that's why I crushed a fingertip by running it between 2 (loosely meshed) gears a month ago due to a moment's stupidity. It's on the mend slowly but not an experience I'd want to repeat!   Just bear in mind that it's a powerful tool - as others have said, invaluable for modelling and a host of other uses but wll take no prisoners!Edited By Martin Harris on 24/10/2010 20:44:23

Posted by Myron Beaumont on 23/10/2010 13:59:38: I wonder again of the value of an "A" certificate regulations /buddy leads /instructors etc.versus experience ? Something is wrong if most of you guys accept the fact that your model won't last very long .            Unfortunately, experience can't be trained or bought and for most mere mortals it means that they either remain very much within their comfort zone (and make very slow progress) or push the envelope and gain their experience through the school of hard knocks.   These are the average people, of course and we do see exceptions who make extremely fast and effective progress (usually on the younger end of the spectrum) and those whose co-ordination is poor or ambition is very much ahead of their ability who will often return from a flying session with a filled black sack.   What seems clear to me is that without  "A" certificate regulations /buddy leads /instructors etc. the model attrition, new pilot drop out and personal accident rates would all soar. You must be one of the lucky individuals who, through your free flight modelling experience, attention to detail, natural ability and probably a sprinkling of luck has progressed through inexperience without incident but I'm sure this doesn't hold for the majority.   I don't want to sound confrontational but, quite frankly, despite the deep level of experience and expertise you claim, I'd have more respect for your views if you backed up your assertion that you could do the A test inverted - to my knowledge there's nothing in the regulations stopping you doing so. Why not show us all (even conventionally) how it's done? Are you speaking from direct experience of a (modern) club environment or are your opinions on clubs and certification purely anecdotal?Edited By Martin Harris on 24/10/2010 01:00:29

Wrap a little masking tape round them?

Ideal use for one of the new cloned receivers?

I don't know the Powerbox 12 but normally you would need a separate glow battery. BEB has answered everything else...

In general, club rules take precedence over BMFA guidelines but I wonder if your club's A tests are actually valid!

The accepted wisdom is that an ABC must be run in close to normal temperature in order to avoid damaging the rinning fit at the top of the tapered bore.  If it is not hot enough the fit is made too loose at running temperature meaning that compression will suffer.   How much is too cool (rich) is the million dollar (well £50) question and one which needs a metallurgist to answer.  Best bet is to use the extensive resources of the manufacturer which should be encapsulated by their running in instructions!   Failing that I'd go along with Lee -adding that the important thing is to avoid ticking over or running excessively rich - or lean - and overloading the engine. As soon as an ngine will hold constant revs at a slightly rich setting I like to get it in the air (in an adequately cooled installation). Fly at varying throttle settings and no prolonged prop hanging!

Had me scratching my head as well!

Using an AGS in mode A you plug it into the throttle channel and the throttle servo (or servos via a Y lead in your case) into the connector on the AGS.   See their handbook for full details...

I was interested to see a comment earlier in the thread that someone found it more difficult ON the buddy lead but I'm sure it's more common for people to feel additional nerves when they lose the link - but it can also act as a massive confidence boost once the initial nerves are conquered.   One thing that worries me is that someone from Jeff's club could take themselves off anywhere - maybe to a semi-public fly-in with their shiny new A cert having never flown on their own before.

Jeff,   I understand why your club wants to get pupils to a high standard before coming off the buddy lead but surely they must feel someone is ready to be off the lead if they are ready for the test - which should surely be done as a solo performance.   Isn't it a given that the A test should be flown unaided and without the added comfort factor of an experienced pilot a click of the buddy switch away?   I hope your club is unique in this approach - or are there others out there that see it differently?

Posted by kc on 20/10/2010 19:20:51: If you look at this website You will see that they are selling what they say are non CE marked receivers (in Britain I think )&   they say in the data that you will  not be covered by your insurance.  Surely this is ridiculous!  Who but a fool would fly something uninsured.  Why are they selling them?   Where is the BMFA when you need them?   I'm sure AeroModel Hut will defend themselves if they see this but as far as I can see they're taking pre-orders against completion of their testing and CE declaration.   What I would take issue with is this continued assertion that insurance is invalidated because there's no sticker on the package. There's no evidence that I've found to indicate that there's any possibility of this and as BEB has pointed out ad nauseum on this and other threads, you are NOT breaking any law by simply using one - but you would by selling one commercially and this firm are apparently taking the responsible route, from information on their website and other postings to this forum.Edited By Martin Harris on 20/10/2010 21:24:40

'Tis all to do with Timbo's request to kc

Does your club ask you to take the A test on a buddy lead, Jeff? Is this practice used by anyone else's club? Edited By Martin Harris on 20/10/2010 15:04:18

Posted by Biggles' Elder Brother on 19/10/2010 22:23:10:   Never flown a twin (a pleasure still to come) but I think Martin's advice about using the beat frequency to synchronise them makes perfect sense (afterall its how they do the full size!) rather than use the tacho. BUT...you can use the tacho to establish which is the faster engine and to double check that the beat frequency method has given you a sound result.   BEB   I didn't put that bit very well BEB - I meant that after establishing which was the faster engine with a tacho I don't bother using the tacho for the actual balancing...but you're quite correct as well!

Yes, an excellent way to put fuel through the new engines in an ideal environment and check them out.  Plenty of power and heat variations if you fly a range of manoeuvres...   Once you're thoroughly familiar with twin handling and particularly with your specific model it is probably practical to fly on one engine but I've seen very experienced pilots fall foul of turning into the dead engine and of course, even the real thing tragically caught out the very experienced pilot of the BAe Mosquito as you've seen.    Edited By Martin Harris on 19/10/2010 22:18:23

That's an answer that will get a lot of people interested in your site.    Good luck with your venture!

I ran a similar length on a converted from electric (hee hee) Hellcat Slim funfly to get the slime past the wing mounted rx and servo bay - possibly longer - with no ill effects.  Make sure it's got as large an internal diameter as practical.  I accept I might have hit a lucky tuned length but try it!

Runs for me in IE8   Now I don't know if I should ask this but will your Orange 2.4 GHz receivers be CE  (genuine - not "China Export") stickered - and if you're importing them directly are you prepared to take responsibility for their compliance?   Did I really stir that hornet's nest????Edited By Martin Harris on 19/10/2010 21:21:59

There's no major difference in principle - earlier ones tended more towards air bleed carbs but most have the same 2 needle type as the average modern 2 strokes.   It's important to use a good 4 stroke plug as there's quite a gap between firing strokes while it blows, sucks and squeezes giving the element a chance to cool. Although some will say you need to tune with a tacho, I think that it's quite OK to do it by ear if you've got a good one. The usual principle is of tuning to max revs and then richening until a discernable drop in rpm is detected - a good secondary cceck is that there shouldn't be any significant change in note when doing a nose up check - don't hold it nose up and flick the throttle open for 1/2 a second as so many do - let the rpm settle while level - THEN - go nose up and there should be little or no change in pitch when held for several seconds.   Many people will say that you shouldn't need on board glows but, particularly on a scale twin, I'd go along with the idea. It allows you to start without external wires to tangle and extra holes in cowlings. It also means that the low end can run reliably a little richer than ideal which gives a small extra margin against unintended overleaning from partial blockages, bubbles, G loads etc.  I've always found the South Herts Models Intelligent Glow Systems work well   Now the thorny subject  of tuning twins: People seem to spend hours messing around with tachos trying to get the engines within 10 rpm.  The important thing is to run in both engines until they're happy and tune them to run and throttle perfectly.  Once this is done and with the linkages set up as identically as possible (servo arm lengths, angles etc.) check the rpm output and richen the faster one to drop the rpm to atch the slower one.  I don't bother using the tacho for this - if you hear the "wonderful" twin beat it actually means the engines are out of synch! This occurs when the engines are very close but the beats disappear when the engines are perfectly matched.  Having them matched reduces vibration so is kinder to the airframe and might reduce fuel foaming but the important thing is that they are tuned to run reliably.   With a Mossie the golden rule must be, lose one engine, kill the other or kill the model.   Treat one engine out as a dead stick - shut the throttle and land ahead under control unless there is comfortable height to do any turns.Edited By Martin Harris on 19/10/2010 20:53:26

Well if you seriously suspected that, it would make sense to check the PCB visually or get it checked out by a service agent but in the real world there's a far more realistic chance of referred damage to the adjacent wire or connection plus there's always the question of why Futaba thought it worthwhile to put 25mm of wasted plastic on the end.   Perhaps the idea is to give you 27 nanoseconds warning that you're about to trim something useful off the end?

LAs aren't the easiest engines to hand start due to their plain bearings adding drag and the tendency for fuel to drain back to the tank. If you're hand starting you really only need the throttle at tickover.   What you need to do is, before connecting the glow, open the throttle fully and either cover the air inlet with a finger if it's accessible or, assuming you're running exhaust pressure, over the exhaust and turn the engine over repeatedly watching for fuel going up the clear tubing from the needle valve to the carb. When it reaches the carb, turn the engine a couple of more revolutions and close the throttle until there is a tiny gap in the choke (tickover position) which will tend to stop the fuel draining back as well as being the best position for hand starting.   Connect the glow, give it a flick or two and you're in with a good chance of it bursting into life.   Alternatively a priming bottle would allow you to inject a little fuel directly into the carb.   Really, these engines are best started with an electric starter, especially when new and not run in - even once run in often responding to a finger over the exhaust until the fuel is pulled through.Edited By Martin Harris on 16/10/2010 23:01:11

My wife has had good results from visiting a chiropractor.  I've actually seen her walk unaided from a session having had to virtually carry her in.  It's not a cheap remedy and I can't guarantee it would work for you but it was really worth it for her.Edited By Martin Harris on 16/10/2010 09:41:25