Martin Harris - Moderator

Good stuff, Robin. Oddly enough one of my clubmates announced he was interested in getting some E-Retracts yesterday afternoon - is there a UK agent or should I point him to your site when it's up?

Posted by Richard Wood on 08/10/2010 10:21:27: Same here. Hope it's not a portent...   Reminds me of when a large camping shop chaini folded...due to portents...  Sorry!  

There's unlilely to be any problem as this is normal for a tight tolerance ABC engine. The bore is slightly tapered and expands more at the top as it reaches running temperature - hence it feeling right when it's warm.   This is the reason why you should run in at only slightly rich settings - rather than the slobbery rich settings needed for a ringed engine.Edited By Martin Harris on 07/10/2010 23:49:40

I had some plans scanned and printed after I'd enlarged them at a firm called Aneataprint in Watford 01923 819 779 who have branches in central and NW London.   They were very accurate, reasonably priced and could print virtually any length on A0 and (for a considerably more expensive price) slightly wider top quality paper.   I don't think they are unusual in printing off the roll though, so it might be worth talking to local firms, assuming this one would be well out of your way.  

I do recall reading about them in the magazine and yes, they do look very tidy but I'm talking about electrical and electronic complexity. If something should get hot in that little box it could potentially fry the whole thing - then where are you?Edited By Martin Harris on 07/10/2010 13:27:49

Posted by David Ashby - RCME Administrator on 07/10/2010 13:09:28: The Powerbox Digiswitch reduces complexity   1. it's not a mechanical switch so removes a potential source of problems in higher current applications 2. It has a built-in regulator so saves space and wiring.   It's a beautiful thing     I'm not sure how introducing a regulator and electronic switching can reduce complexity but I'm sure it's a clever bit of kit. However a GOOD QUALITY switch of sufficient rating is unlikely to fail and is backed up anyway in my favoured system. Edited By Martin Harris on 07/10/2010 13:23:42

Highly recommended method for electric retracts in case the servo stalls.   You need a Y lead and to remove the power feed from the receiver (Futaba red lead) on one leg and connect the battery to the other.  I think Timbo has a diagram somewhere...?Edited By Martin Harris on 07/10/2010 13:17:18

I've used the 2 battery, 2 switches, 2 connections to the receiver methd without any diodes etc. method successfully. The only requirements are that the batteries are the same technology and cell count and that they are charged seperately. You can add a diode to each pack if you use 5 cells if you want to but it isn't essential.   In my opinion, introducing a power box with multiple components and connections introduces an excessive number of potential failure points but some form of back-up is always a good idea in a largish or expensive (in monetory or work terms) model.Edited By Martin Harris on 07/10/2010 13:04:26

Posted by Tim Mackey - Administrator on 07/10/2010 11:35:38: A pleasant update on this matter - I started it off by referring to the cheapy little spektrum clone receivers from Hobby City - having just looked again at some un-opened ones, I am relieved to see they do in fact carrry the CE marking on the "packaging". Yippee. Now, just my luck, BEB is gonna tell me thats the China Export mark instead    I don't know what BEB will say but it doesn't appear to conform with the CE mark which is based on segments of 2 adjacent overlapping circles.   Edited By Martin Harris on 07/10/2010 12:47:20 Edited By Martin Harris on 07/10/2010 12:50:03

Robin,   From your new viewpoint, how do you view the point about the electronics being kept seperate from the mechanical unit?  Will you be pressing for a re-design?    

Posted by Steve Hargreaves on 06/10/2010 14:06:37:   Seems a typical 4 cell AA Rx pack will be more than adequate for most "Sports" applications then..... Always has been!

You would think that, wouldn't you!

..and stock up with some goodies as well.  You did, didn't you? They are the onlt stockists I've found of 2mm nylocs - invaluable!

Go with modelfixings as Andy suggests - you'll get them the next day and they stock 16mm length amongst many others...

All I can offer is that I would be wondering what was wrong if I put more than 270 - 300 mA back into an average 5 servo sports model after 3 10 minute flights and that would include any fiddling time either side of flying and a few days of inactivity.Edited By Martin Harris on 05/10/2010 20:23:53

Posted by eric loakes on 02/10/2010 19:02:50:   By the way as from now, I'm an electric flyer !!    Eric.   Perhaps when you get a bit older you'll get over it and do some proper modelling!   I always say that there's a place for electric motors in any model   ....in the servos!   (say's me who's probably done 70% of my flying on EP models this year - but I'm an oily man at heart)    

I'd imagine Mick Wilshere's favourite method will work on the bigger Supertigres just as well as the small ones.   Put a clean piece of tubing on the fuel nipple.  Open the throttle barrell by a 1/16" or so (use a drill or similar to guage it if you like).  Open the main needle 2 1/2 turns. Blow through the tube while opening the idle needle slowly from closed until you detect a small but positive flow of air.   You now have your initial setting!

Perhaps you should build a bit lighter?Edited By Martin Harris on 04/10/2010 22:58:33

Dan, I'm glad you're approaching this with an open mind and I'm sure you'll see where we're coming from because of it. You seem to have pretty much got there in your later paragraphs anyway!  With your downwind hand launch it takes time to gain airspeed because you're starting with minus airspeed because you are attached to the ground so you need to make this up - as opposed to into wind where before you do a thing, you've already got some airspeed.  Try the same from each side of a free floating hot air balloon and there will be no difference between those launches.  With your "crosswind" turn, it's only crosswind from your static viewpoint.  The model continues to drift in it's "block of air" and doesn't feel the effect of the wind that you do. Edited By Martin Harris on 04/10/2010 15:30:44

I wouldn't advise charging at more than  1C and then not on a regular basis.  1/10C is ideal but you probably can't go below 100mA which is what I'd use on a regular basis. For discharge but most of these chargers don't do less than 500mA - so that's what I'd use.

Profilm removes without leaving anything other than a small amount of glue residue (uncoloured) in the wood fibres and more or less ready to recover. Solarfilm leaves the coloured residue.

All I can say is that making best guess alterations to RF systems is at best risky and at worst could result in prosecution or even more dire consequenses if an accident were to occur. Using an aerial which boosts ERP would definitely be illegal although I'm not qualified to say if a directional aerial actually does so (Tony)

Posted by David the flyer on 03/10/2010 22:32:45:  I spoke to a club member and he said that was ok, it's a preference if you want the engine to point slight left and down, his yak, he has the engine in a slight up position, he said it's better for landing?  

Up thrust usually leads to rather nasty trim changes with power so I don't see how adding it would help with a landing. As you reduce power for the flare, it will tend to pitch the model nose down - probably resulting in a rather undignified arrival!

Don't Spektrum supply an aerial that will attach to the module?  I assume this is what you want to do and looking at various adverts they all seem to come with remote aerials.  I think this query would be better addressed direct to Horizon as there might be legal repercussions should a non-standard aerial create RF anomalies. It might well be that the aerial is a "standard" part but only the manufacturer/designer can confirm it with any authority.