Here is a list of all the postings Geoff Sleath has made in our forums. Click on a thread name to jump to the thread.
|Thread: C rating on Lipo's|
My Wayne--Giles ESR meter would agree with Marty as I've discovered lots of times - in fact I've yet to check a LiPo where the measured ESR justified the quoted C rating.
OTOH I don't know the criteria for setting C rating. Certainly it depends on the ESR because that's what determines the terminal voltage on load as well as the power dissipated within the battery itself but I don't know what the accepted terminal voltage nor the temperature rise over what load conditions.
I don't usually over stress my LiPos and particularly with large capacity ones get nowhere near the quoted C rating. Obviously EDFs need to draw a lot of current. I suppose a high C rating implies a better quality LiPo but I doubt if it's worth the extra outlay if taken to extreme.
|Thread: Geoff's DB DH60 Moth|
Looks very good, Jan. I was lucky and managed to avoid any extra ballast. The 4AH 4S batteries I'm using proved to be just the right weight.
Good luck with the maiden. The weather in the UK has been a bit windy mostly but there have been a few dry, light wind days. I managed afew flights with mine in the unseasonal warm spell we enjoyed last month. Let us know how you fare.
|Thread: Does your club prohibit the use of after-market receivers?|
I can see no logical reason for any ban provided a model satisfies and range checks etc. I think there're likely to be far more problems with a poor installation than anything related to the radio system.
I'm always conscious of how ephemeral our contact with the model is despite having been involved in electronics of one sort or another all my life (or perhaps because of it!). I'm always slightly bemused by the total faith most have that nothing will go wrong.
I wonder if a club would insist that members only fly ARTFs assembled exactly as the instructions or kits built identically to the plan. I think very few are with the possible exception of almost ready to go foamies. I know that just about all my builds have a few of my own foibles included (like electric motors rather than glow )
|Thread: NEW POLL - Does your club have a safety officer, or is the emphasis on individual members to each be their own safety officer?|
I think we have a safety officer but I'm not sure who it is. However we have a few of what I think are sensible rules.
1. No taxiing in the pits
2. There's a written map of where we pit and fly depending on wind direction. Mostly it's the same place except when the wind blows directly into the pits.
3. No overflying of the pits or car park. There is a no-fly zone but it's not restrictive.
4. No cars to be left in the pits other than loading/unloading (we're lucky)
5. Flyers and those waiting to fly (ie take off) are expected to communicate with each other and new members are (politely) asked to do the same.
Mind you that didn't stop the chairman overflying the car park and stuffing his model into the back of the (steel) hut. Luckily it did very little damage to the car it fell back on. I think there were 'words' but the car owner was fairly relaxed. When there are a just a few there, rule 4 tends to be ignored as we can fly safely well clear of the pits.
|Thread: Castor oil in 4 stroke engines|
I was known to put a few drops of Castrol 'R' in the fuel tank of my vintage (actually post-vintage because it was 1932) Scott TT replica just for the smell The lubrication was a bit hit and miss anyway with its Pilgrim pump drip feed.
Certainly wouldn't use it in a model engine though.
Edited By Geoff Sleath on 15/03/2019 20:07:55
|Thread: How to reduce voltage?|
A silicon diode will certainly drop 0.6/0.7 volts. Just make sure it's got a high enough current rating as Martin writes. However, I notice you just mention what the power supply manual says the voltage spec is. Have you actually measured it? It may be well over 14v - especially off-load. In which case the diode may not be enough and you may need 2 in series.
|Thread: Boeing 737 Max 8|
Some of my former colleagues at RR flew in an old Boeing owned 747 that was so leaky it couldn't be properly pressurised and had some training about using the oxygen masks provided. IIRC they were involved in monitoring the engines via the RF telemetry our department designed. This would have been in the early 90s I think.
So yes, engineers do fly on aircraft with engines being tested.
|Thread: Field Box|
I used a fairly tired 3S 2200 mAH LiPo to start my Zenoah 26 with no problems. I know I should be able to start it by hand but I've never managed it A lot lighter than lugging a 12v lead acid around.
|Thread: R4 Life Scientific - Ken Gabriel|
Listened to this as I was eating breakfast today. It's repeated at 9.30 this evening.
Ken Gabriel is the engineer largely responsible for the design of micro-mechanical devices ie the solid state gyros and accelerometers used in a lot of the stuff we use in modelling and elsewhere.
He's also involved in the design of a modular smart phone which would allow you to update the hardware modules as well as the applications (I refuse to call them apps ).
A very interesting 30 minutes. It won't be available on BBC 'Sounds' until after the repeat broadcast but well worth 30 minutes of your ears.
|Thread: Big Trouble in Model Britain|
I knew 'Tich' Allen, the founder of the Vintage Motor Cycle Club, and that was exactly his attitude to old motor cycles. He always said that they should be used rather than be restored to within an inch of their lives and displayed in a museum. He was known to clean motor cycles with a paint brush A friend of ours used to passenger for him in vintage sidecar races. She still rides a BMW sidecar outfit as her normal means of transport. I'm not sure old she is but certainly north of 70
I was once 'told off' at work because I occasionally rode my wife's 1928 250cc Raleigh to work to give it a run. It was very pretty and he seemed to think it was for display rather than use.
|Thread: Thanks for everybody’s time to reply|
I think I prefer it that way round otherwise we would have been building and flying some very odd looking models.
PS I'm surprised Boddo had time to anything else other than be deeply involved in designing models, writing books about models and publishing model magazines. I never knew he was an architect.
|Thread: hobbyking prices|
My wife used to work for Silk Engineering who manufactured the Silk 600S motor cycles using an engine loosely based on the Scott water cooled twin 2 stroke. She was responsible for ordering components and the once mighty Lucas motor cycle division was reduced to one guy at a desk and presumably some manufacturing somewhere. She eventually had to source alternators from somewhere in Europe (Italy IIRC, it was some time ago).
We've lost touch with George Silk over the years but he was (is still I guess) a very enthusiastic and hard working guy who really believed his own nonsense. We used to holiday with him in a crowd of motor cycle enthusiasts. It was a valiant attempt to manufacture an innovative motor cycle but it was doomed to failure.
Edited By Pete B - Moderator on 10/03/2019 22:09:15
|Thread: Big Trouble in Model Britain|
I liked the museum curator, too. The way they 'bleeped' his opinions of the former management with loco images across his mouth was brilliant.
I built a few Airfix kits when I was much younger (that would have been in the early 50s). I assume they were Airfix. I remember making a so-called Red Label Bentley as well. My main problem was the finishing and detailing (I'm the same now) so they never really satisfied me.
I had a model railway which I used a lot. It wasn't a Hornby Dublo but a Trix Twin. I had lots of track and especially points because I liked making goods yards and shunting. I never bothered much with scenery but I was fortunate to have my own play room (it was a very big house) so I could have track on the floor as long as I chose.
The local squire (the family of the former coal owners) was a customer of ours and he had a huge model railway layout in the basement of his small stately home. He used to get local railwaymen in to help him run it.
I think a few of us are in the same boat but flying model kits tend to be bigger than plastic ones so we need either more space or fewer kits
I wasn't very impressed with wiring/soldering quality of the switch board they were repairing. I suppose when a poor connection doesn't mean potential total disaster and bits in a bib liner you can be a little more casual.
I've just watched the documentary of that title on the IPlayer. It's mainly about Hornby, so model railways and Airfix kits rather than the sort we're mostly interested in. I found it very entertaining and a lot of it relatively familiar in that it was about the problems facing small manufacturing and retail.
It'a narrated/presented by James May, who I find the least objectionable of the trio of Clarkson/May/Hamilton and who's done a few practical documentaries that appeal to me.
Oddly I find the railway side a bit more interesting than the Airfix 'planes. Mainly because they actually move on rails whereas the planes don't fly.
It's worth a look. It's on BBC 4 - part 1 of 2.
|Thread: 6s lipo battery and shipment ?|
Actually, I think I'd included a spare battery but it was a while ago.
Pointless regulations? Not so sure. Years ago I used to write assembler software for microprocessors when they were very new devices. We were all hardware designers and knew nothing about software beyond teaching ourselves from the data sheet. I'd review what I'd written and occasionally found apparently purposeless sub-routines and delete them. It was only then I discovered why I'd included them because things went wrong in strange ways. I suspect the same may be true of some apparently pointless rules and it's not until they are repealed that we discover why they were there in the first place ie the rules of unintended consequences.
I think it's just RM that are cagey about batteries and not just LiPos. I had to lie when I posted a transmitter I'd sold on eBay that there were no batteries in the parcel ... I was ashamed of myself It was an old FF7 with the usual NiMH battery pack.
|Thread: Gone,but not forgotten kit mfg|
Well, here's my Skyways quarter scale Mew Gull. Test flown just over a year ago;
|Thread: hobbyking prices|
I've used the HK film quite a bit and it's more akin to Oracover than Solarfilm in its quality and a lot cheaper than either. I've always bought from the UK warehouse. I'd certainly use it again. The only thing I regret about the loss of Solarfilm is the loss of Solartex; the other coverings weren't anything special and Solarfilm itself a lot harder to use IMO.
|Thread: Gone,but not forgotten kit mfg|
All those adverts pre-date my interest in aeromodelling but I did build a Howard Metcalfe Moonraker which IIRC I powered with a Irvine Q40. Unfortunately it met a dumbthumb ending.
A club mate has a Veron Avro504N and has been flying it electrically powered recently. I use the term 'flying' very vaguely because it's bitch in the air. He's tried it both with and without ailerons and changed the CoG with little success. It really seems to have a mind of its own and even the ace pilot in our club who can fly just about anything finds it very difficult (though it looks fine when he's in control).
It was built years ago apparently and has been something of a challenge all its life. Just a warning. Perhaps Les made a mistake in the build but his other models are OK and he's a reasonably competent flyer - better than me though that's not saying a lot
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