 Danny, get that motor mounted and run some tests, I'm dieing to see some results.Timbo, not on your scale obviously, but I flew a DB Sprot and scale 56" Tiger Moth first flight yesterday on a 670KV Motor on 6M1's and a 12x6. (had the motor, cells esc spare and it made the cg spot on). Was so good I had 4 flights, last one must have been over 10 mins and I only put 1000mAh back in. I was very pleasantly surprised how slow and sedate the flying was. Having never ventured into scale or bipes before. Took more rudder than aileron to fly, but everyone had warned me about that.If you like the look of the field, I'm hoping to be there this afternoon with a live webcam. This is another practice for our funflys. Mind you on a day like today, I can't see anyone looking at a website this afternoon lol. If yr interested see greenacresmac.co.uk
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 Whats a "sprot and scale" then Chris 
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 Its a Midland thing 
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 you may have to get used to my spellling!
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 Here are the motor and ESC the motor was $29 and the ESC $11.95 (note US dollars) The sexy mount is not going to be used as it was a whopping $11 and this is a budget build so we will do it the Screwfix way The Screwfix components, A 1/4 ply (real ply not funny lite stuff) drill a hole to centre the mount More later (thanks Mr Redshaw great tip) holes to mount the "mount" assy to bulkhead of model and obviously countersunk holes to allow the 50mm long 4mm steel bolts
.JPG) And here it is ready to go, infinitely adjustable but I rarely alter mine once made. Note the nuts directly behind motor are NYLOCS this stops them spinning at random lol and makes setting up the distances from the bulkhead to motor easy. Using a short 4mm bolt and wing nut, lossely mount this assembly on the model using the hole for the fuel tank in the models bulkhead. loosely fit the cowl and then slide the motor mount assembly around until centred. Once happy, pinch up wing nut to clamp it all together, drill through the 4 unused holes straight through model bulkhead, fit blind nuts at the back and mount entire motor asembly to model bulkhead as though it were a normal IC mount. I will include more pics when I come to it for those that haven't a clue what I am on about lol .JPG) Centreing the motor in a radial cowl is easy when you know how, I am afraid I owe this one to Phil Clarke of Fighter aces (thx Phil) simply make a card or stiff paper disk the size of the cowl opening. Mount this on the motor and use the above procedure. everybody still with us 
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| Edited: 11/05/08 10:52 |
 prop size ?
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 I have a big box full of props, I like BIG props they look better in flight but the high KV and current levels will dictate that. Timbo I am currently flying using JEN wooden IC props, they are quieter than the APC thin electric jobs, have you done any thrust tests between the types of props for the BIGGER stuff? Might make an interesting article sometime??? Are we the only ones watching this thread we haven't gone and got to techie have we? Don't want to alienate potential smoke tamers.........
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 Me too. I have tried wooden props ( mainly beech ) and like them, but they break easier of course - no thrust comparisons yet and anyway static thrust only tells half a story really. Yep just us 3 geeks me thinks I am off flying now. CU l8r
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 Just tuned in here, having got back from flying..............electric only...........since 07:00........ SO, Geek 4 reporting in............... Reasons? 1. Sea Fury! 2. Hurricane! 3. The Seagull model, which I''d thought of buying, but don't want to go smoky oily...............  Mention 1 AND 2 in any thread and you'll have my attention............  Looking all good stuff so far, but the unsupported length of those motor mount screws concerns me a trifle..that's a very powerful torque/vibration creator dangling on the end, esp if the prop/etc balance is not perfect. More!!!
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| Edited: 11/05/08 12:31 |
 You would not believe how strong that mount is. We have been doing it this way for nearly four years and never had one give way yet. The YT Hurricane uses 5mm instead of 4mm and that was producing nearly 3kw!!! We have several 600 - 1kwatt models that use this method to, trust me its rigid. Several manufacturers AXI included do not recomend you mount the motors this way around, I personally nearly always do so that cooling air is not impeded on getting to the front of the motor. And I prefer a bolt on prop adaptor as opposed to a collet which can be a pain when trying to change a prop.
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 Yeh..I can vouch for the stud and nut method too...works fine.
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 Just out of interest here is the Eagle Tree data from the 2kw Hurricnae flight: Hope the size restriction doesn't make it to small to read??
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| Edited: 11/05/08 16:30 |
 Did anybody notice the 70" miles messenger featured in a recent Magazine? 23 watts per Lb, now that Eagle tree I have got to see!!
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 nah cant read it Danny boy e-mail me the fdr file?
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 Did anybody notice the 70" miles messenger featured in a recent Magazine? 23 watts per Lb, now that Eagle tree I have got to see!! Nope....QEFI by any chance ? 23 Wplb Thats low !! dont let Scott see this he will faint 
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 Dave, forgot to say welcome to the thread, a Camm nut, a man after my own heart You looking forward to the forthcoming Hurricane from Mr N?? Timbo no RC Model World, but don't tell Dave I read other magazines he will have a fit........ However the aformentioned 70" Messenger did only weigh 4lbs, but 90 watts is still impressive. I bet the takeoff run was measured in miles rather than feet. PS I have sent you the FDR file.
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 Cheers matey.
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 Been busy and not had a chance to get much done. Latest is that I have another motor from UH now MUCH BIGGER LOL and a nice big ESC. However I am now really intriqued to see if this will go with the power plant selected. The Seagull Fury comes with an overly long cowl, looking at a three view shows that this is more like the cowl fitted when the Bristol Centaurus is substituted for the 4 row 28 cylinder Pratt and Whitney R-4650 converted racing FB.11 This has benefits for us. If we leave the cowl as long as it is then the smaller motor will keep the c of g correct, if we fit a larger motor we can shorten the cowl. For initial tests I will leave it long and if we need the bigger motor will shorten it. I much prefer the shorter look to be honest. I am supposed to be building this as per the book but I really couldn't bring myself to fit the tailwheel in the manner described, I am sure it would work fine but it was bulky, ugly and heavy. I have substitued the wheel for a slightly larger one for the grass field I fly from and used some piano wire and appropriate sized carbon tube as a bearing. This is epoxied into the fuselage solid block that runs along the bottom. We will have to see if this method is strong enough, and whether a castoring tailwheel is okay when taxiing. This is the original fitting My replacement parts, the wheel was from UH and was less than $1 And here it is fitted, a collet locks it in from inside. I could have made it steerable by fitting a t-bar to a collet. But for the interests of expediency didn't bother.
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| Edited: 15/05/08 11:00 |
 Okay tail feathers are fitted, and the elevator halves joined with some chunky SLEC Piano wire. Neat trick with the fluffy hinges is to use PVA on hinges as you fit them, not Cyano bled in after they are fitted, the PVA holds solid but doesn't stiffen the hinge material unduly. You have to work quick though it dries pretty quick. One of mine dried half in and half out, devil of a job the remove. Reassured me that the PVA is the way to do it  All the horns are Glass Board sunk full depth into moving surface with several small holes for keying. Bonded with 30 minute epoxy. I have used swing keepers on the servo ends of the control rods, I like to use my Z bender but the piano wire in many ARTF's is so poor it often snaps, and as theses lengths are fairly long didn't want to risk one snapping. Getting there.
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 Well in the best practice of reviewing a model as supplied, I fitted the sad looking pilot that came with the model LOL Glued the canopy on with RC Modellers glue, you all know of this stuff right???? Anyway takes forever to dry  Doesn't he look silly, bit like a switchboard operator lol, Shaun your be-sweatered nautical chap was much better LOL I can see this model getting a serious makeover if it flies okay 
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| Edited: 15/05/08 17:59 |