Tim Mackey Posted February 9, 2012 Share Posted February 9, 2012 LOL...oh the irony of that last sentence ( PS I do actually agree with Lee though, despite also hating bad spelling ) Quote Link to comment Share on other sites More sharing options...
Myron Beaumont Posted February 9, 2012 Share Posted February 9, 2012 Peter You missed out a comma after the word "done" (being as we're getting pedantic about grammar) Myron YO13 language dept. PS Like your latest plan but only have a 52 Fst ,so slightly too small .Or is it ?Edited By Myron Beaumont on 09/02/2012 10:05:14 Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted February 9, 2012 Share Posted February 9, 2012 I used to edit and publish a magazine for a car club in a past life, and the worst articles to check for spelling and grammar are the ones with very few mistakes in the first place. This is of coarse why my submitted articles are so bad, it makes it easy for Graham and the team to spot them Well that's my excuse....CheersDanny Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted February 9, 2012 Share Posted February 9, 2012 Myron. I admit that my punctuation could be better. My spelling is not brilliant aided and abetted by a dyslexic keyboard (The key are too close together.) Harlequin would be fine on a .52 FS. I have seriously considered fitting my .48 Surpass to mine but it is in use at the moment. Quote Link to comment Share on other sites More sharing options...
Myron Beaumont Posted February 9, 2012 Share Posted February 9, 2012 Thanks Peter .I shall empty out my boxes of wood today and see if I have all the materials necessary .I have a 52 2st as well . Which one would you recommend please ?Tank position comes to mind straight away but not a problem really -plenty of nose room I see .As long as I don't have to add church roof -that's the main factor in my book . Myron Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted February 9, 2012 Share Posted February 9, 2012 A .52 two stroke would be well over the top. The four stroke would be perfect. Quote Link to comment Share on other sites More sharing options...
Daithi O Buitigh Posted February 9, 2012 Share Posted February 9, 2012 Mine arrived yesterday (the paddlers must have got a shot of something to make better time) Spelling? The problem isn't so much with the authors but the proof-readers. If you mis-spell something that also is a word, those who depend on spell-checkers will never spot the error. I've a very bad habit (due to my Hunt and Peck school of typing) of typing ion for in, toy for you and thew for the - unfortunately those are all 'real' words I kan spell wel - my key broad unfortunately has other ideas Quote Link to comment Share on other sites More sharing options...
Tony Jones Posted February 9, 2012 Share Posted February 9, 2012 David What's the correct procedure when opening a New Topic that is inspired by a particular feature in a particular issue please? Currently, IMHO, posts about various topics appear at random under the issue feedback thread. Best wishes Quote Link to comment Share on other sites More sharing options...
David Ashby - Moderator Posted February 9, 2012 Share Posted February 9, 2012 No procedure as such Tony. If it's just a general aside/comment then perhaps the issue feedback thread (such as here) is better but if you're keen to start a discussion on a particular point then feel free to start a separate thread - much as you did with the Woo thread. Probably better to put the thread into the specific forum topic folder where, in theory, it's more likely to be seen. Quote Link to comment Share on other sites More sharing options...
ken anderson. Posted February 9, 2012 Share Posted February 9, 2012 further reading reveals that 'enrico' gets a mention in the mag also....... some wheeling and dealing he did with andy .. over... a glider.... ken anderson ne..1 enrico's dept.. Quote Link to comment Share on other sites More sharing options...
Prop Nut Posted February 9, 2012 Share Posted February 9, 2012 I don't think Seamus and I are using the same dictionary, as mine doesn't have a listing for 'pedentry', but it does tell me that the word 'photograph' is derived from the Greek meaning 'drawing with light', and that a picture is 'a visual representation of a person, object, or scene, as a painting, drawing, photograph, etc'. So, whereas all photographs are pictures, not all pictures are photographs. Quote Link to comment Share on other sites More sharing options...
Tony Jones Posted February 9, 2012 Share Posted February 9, 2012 Posted by Lee Smalley on 09/02/2012 09:42:11:I am the worst speller in the world so maybe I am being a touch biased here but I would much rather read a fun, witty engaging or detailed and informative article that has the odd spelling oddity than a dull, dreary, poorly written ill informed fact file, that entertains about as much as opening a can of beans. Actually Lee, the best of both worlds is not that difficult to achieve - at least on a 99.9% basis. And I speak as someone who proofs read final copy for a couple of trade magazines. When did you last see serious spelling mistakes in a daily paper (The Sun not included), or a mainstream magazine. Regards Quote Link to comment Share on other sites More sharing options...
Tony Jones Posted February 9, 2012 Share Posted February 9, 2012 Posted by Daithi O Buitigh on 09/02/2012 11:43:31:Mine arrived yesterday (the paddlers must have got a shot of something to make better time) Spelling? The problem isn't so much with the authors but the proof-readers. If you mis-spell something that also is a word, those who depend on spell-checkers will never spot the error. I've a very bad habit (due to my Hunt and Peck school of typing) of typing ion for in, toy for you and thew for the - unfortunately those are all 'real' words I kan spell wel - my key broad unfortunately has other ideas It's also very difficult to spot your own typos and grammos. Ideally, proof reading should be done by someone other than the writer. If that's not possible, then the best thing is to leave it for a day and then come back and read it word by word, ignoring the meaning if possible. When that's not possible, then typos inevitably creep in. And I'm as bad as anyone. Regards. Edited By Tony Jones on 09/02/2012 21:16:14 Quote Link to comment Share on other sites More sharing options...
Seamus O'Leprosy Posted February 9, 2012 Author Share Posted February 9, 2012 Hellcat don't worry about those ancient Greeks cameras hadn't been invented.You paint a pictureYou take a photograph Quote Link to comment Share on other sites More sharing options...
Daithi O Buitigh Posted February 10, 2012 Share Posted February 10, 2012 Actually to be pedantic - the suffix 'graphy' is actually to do with writing - not drawing. Think of lithography, calligraphy,xerography and a host of others which all refer to words and not necessarily pictures From Wiki "The English suffix -graphy means either "writing" or a "field of study", and is an anglicization of the French -graphie inherited from the Latin -graphia, which is a transliterated direct borrowing from Greek" Hey Seamus - fancy trying to explain 'grianghraf' (seems when we invented the word, nobody thought about flashbulbs ) Quote Link to comment Share on other sites More sharing options...
IanR Posted February 10, 2012 Share Posted February 10, 2012 Hello to all proof-readers, Take a tip from me - never proof read "on screen" but always use a printed copy. Whenever, I print something, no matter how carefully I check for mistakes "on screen", I always find errors and have to print out again. I use twice as much paper and ink than is necessary! Ian Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted February 10, 2012 Share Posted February 10, 2012 Well I'm not sure how to react here! I mean, should I be pleased that so many have at least read the article? Or should I be dissapointed that the main focus of discussion is whether or not a photograph can be called a picture? Or should I be relieved that at least no one is challenging the physics? Mmmmm, decisions, decisions! Seriously, sorry about the "typos" I do know the difference between "course" and "coarse" of coarse (that's a joke by the way!) But even in the best run households these things can escape - no excuse I agree, but it does happen. As others have remarked it is very difficult to check your own stuff - you tend to see what you expect to see, not what's there! And that's by no means an attempt to shift the blame - the responsibility is fully mine! Anyway - the long and short of it is I must try harder - and I hope it didn't impair anyone's enjoyment of the article too much. Thanks to all of you who have said nice things about the article - hopefully it will help some folks to understand better the way in which a prop loads a power source and the different ways in which IC and electric systems react to that load. Now - back to writing the next one - which is all about "twins and multis" and the aerodynamic consequences - I can feel David's hot breath on the back of my neck as it is a bit late! BEBEdited By Biggles' Elder Brother - Moderator on 10/02/2012 10:18:41 Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted February 10, 2012 Share Posted February 10, 2012 I should take the compliments, its an excellent article.Oooo twins and multis, I really look forward to the next one BEB swirling prop wash, excellent Thank goodness I opted for a Bi-monthly column CheersDanny Quote Link to comment Share on other sites More sharing options...
Lee Smalley Posted February 10, 2012 Share Posted February 10, 2012 I am not sure using a national newspaper and holding it up as a gold standard is a wise thing, yes the grammer may be spot on but their regard for peoples privicy, the truth, facts and the law is something else, you carry on reading that perfectly punctuation, in newspapers mate, and the lies, that go with them, proof readers eh! BEB good article mate keep em comming !Loads in this mag lads well done Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted February 10, 2012 Share Posted February 10, 2012 I read the good Professors article last night & I would like to...well not exactly challenge the physics but at least raise a query.....so, hard hat & body armour in place then here goes...... Now first off I'd like to just say how much I enjoy David articles....he has an ability to explain difficult concepts in a concise & logical way that I can only dream of achieving..... So whats the problem.....? Well it comes down to the IC engine graph concerning the load factors against power...Fig 1 in the article. How was this data generated...? From what I can gather from reading the article it came from comparing the maximum output of a typical engine with the recommended prop sizes & using the formula Lf = D (power 5) x P to get the load factor on the y axis. If this is the case then it can't be surprising that reversing the maths produces the correct prop for that engine. To put it another way if you find a GP42 is rated at 1 hp & has a recommended prop size of 10x6 then this gives a load factor of 0.5million. So you plot a point of 0.5million against an engine power of 1hp. Surely then it can't be a surprise when you look at the 1hp point on the X axis, find the load factor is 0.5million & then do the maths to find the correct prop is a 10x6......!! Or have I missed something...... The other point I wanted to raise was regarding the power of the engines.....power output of any IC engine is related to rpm.....up to the peak power level then the faster you spin it, the more power you get.....so our GP42 may well produce 1HP but it will produce this at around 16,000rpm. It won't turn a 10x6 at 16,000 rpm...more likely 10-12,000 rpm So what power will it produce at 10-12,000rpm? I dunno but it will be less than 1 HP. This is why 4 strokes perform so well in the real world....their peak power may be lower than the equivalent sized 2 stroke but because they produce it at lower revs they get closer to their peak power output on more usefully sized propellors. Just to muddy the waters a bit more then its fair to say that engines don't really produce "power" as such....Power is simply a rate of working & is related to time. Engines produce torque or a turning force & the faster they do this the more "powerful" they are. I can't help feeling that the explanation missed out the element of time. To my understanding the load factor of a propellor has to be related to the speed with which you turn it (speed & time being related) after all it takes a lot more force to spin a prop at 10,000 rpm than it does to spin it at 5,000 rpm.... So I look forward to hearing your thoughts......I'll be here...just below the parapet.... Quote Link to comment Share on other sites More sharing options...
Tony Jones Posted February 10, 2012 Share Posted February 10, 2012 Posted by Biggles' Elder Brother - Moderator on 10/02/2012 10:17:22: As others have remarked it is very difficult to check your own stuff - you tend to see what you expect to see, not what's there! And that's by no means an attempt to shift the blame - the responsibility is fully mine! Oh no, it's not Prof. The contributor should submit the best copy he/she can, but it's the editor's responsibility to ensure that what appears in print is filleted of any typos and grammos that are present in the original. Whether he/she does that him/her self or employs a professional sub editor doesn't matter. The buck always stops on the editor's desk. Doesn't it David? Regards Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted February 10, 2012 Share Posted February 10, 2012 Good question Steve. The GP42 I tested the data on was not part of the data set the line was calculated from - so in that case I wasn't just "reversing the process" and it does show that for engines not explictly in the training set it does work. Fair point on the power characteristics of 2 strokes. I think though the data is valid because it compares like with like - if one manufacturer were to decide to be more "honest" than all the others - and quote real "workable" power instead of absolute max power I agree we'd be in trouble - as that manufacturers engines would lie consistently below the line. Your point about the time dependence of power is spot on - and the data is effectively premised on the assumption that max rpm for all IC engines is approximately the same - a point I made I think in the article, and for exactly this reason. All this means of course data such as this can only ever be a guide - as I said. Using max torque would be intyeresting - sadly though very few manufacturers actually give figures for that. My own view is that the IC data is consistent - it groups quite well around the best fit line - so I think we can be confident that we are comparing like with like. But in the case of the electric data I am much less confident. There's a lot more spread here - which of course (as its based on your database and hence real set ups) reflects the different ways people like to "take their power" - some favouring brief glory, others prefering flight endurance! BEB Quote Link to comment Share on other sites More sharing options...
Tony Jones Posted February 10, 2012 Share Posted February 10, 2012 Re: The Prof's Props. Does anyone know if manufacturers actually put their model engines on a brake to measure the power? Or to be more accurate to measure the torque at various rpm from which the power can be calculated using the formula... Well, I'm sure everyone knows what that is. Regards Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted February 10, 2012 Share Posted February 10, 2012 OK thanks David.....so I'm not going mad after all.....phew... If I understand you then you have effectively eliminated the need to consider time or rpm by assuming that all engines will run at a similar speed in the real world....this would seem to be a reasonable premise for the purpose of the article.....once we start thowing, lets call them, "specialised" engines into the mix then I fear the theory may start to break down......a 2.2BHP Weston 36 turning a 7x12 carbon prop at a zillion rpm might provide an interesting co-ordinate......similarly a 5cc diesel turning a 14 x 6 at 4,500 rpm... If we wanted to get really silly we could include RC car engines.....some of these 3.5cc screamers will produce over 2.5 BHP but at a stratospheric 40,000+rpm......that would need a very small prop indeed..... I also take your point about the electric data too & this demostrates the inherent flexibility of electric power....I think there are simply too many variables to be able to interpret the data accurately on a two axis graph...maybe a 3 axis graph where the Z axis was rpm might be more helpful but difficult to explain/print & probably beyond what you are trying to achieve.... Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted February 10, 2012 Share Posted February 10, 2012 Posted by Tony Jones on 10/02/2012 12:08:20: Re: The Prof's Props. Does anyone know if manufacturers actually put their model engines on a brake to measure the power? Or to be more accurate to measure the torque at various rpm from which the power can be calculated using the formula... Well, I'm sure everyone knows what that is. Regards I don't know Tony but its an interesting point.....I sometimes wonder if the power output figures are just theoretical calculations based on the theortical BMEP of an engine......but I don't know.... I'd be willing to fly out to Japan & interview OS Engines if RCM&E will pay my expenses... I wonder if Neil Tidey (Laser Engines) could shed any light.....as our most famous home grown enginista he seems best placed to tell us..... Quote Link to comment Share on other sites More sharing options...
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