RottenRow Posted September 9, 2021 Share Posted September 9, 2021 Yes I see (or rather hear) what you mean Ron. Very impressive. It sounds like the twins are better suited to warbird models than, say a Tiger Moth or Chipmunk. Brian. Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted September 9, 2021 Author Share Posted September 9, 2021 Not too sure about that Brian, the sound on that last vid has been fiddled around with! Quote Link to comment Share on other sites More sharing options...
Tim Flyer Posted September 15, 2021 Share Posted September 15, 2021 (edited) Amazing sound it certainly seems close! Very close? Edited September 15, 2021 by Tim Flyer Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted September 15, 2021 Author Share Posted September 15, 2021 A bit more tweaking Tim and it'll be there! 1 Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted September 15, 2021 Share Posted September 15, 2021 Sounds a bit more like a Griffon to me… Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted January 26, 2022 Author Share Posted January 26, 2022 It's been a while since I last flew the Sportster so I thought I'd brush off the cobwebs and take it out again (yesterday). A really murky, cold day and despite the fact that the Sportster is a large 'plane it was somewhat difficult to see it against the grey sky. Anyway, the point of this post, having a motor buried in a cowl with no access to the carbs can lead to prolonged initial starting procedures. My usual method is to open the throttle wide and then spin the starter for several seconds to get the full drawn in, no problem after the initial running but first one on the day can take a while. So I decided that I wanted an easier solution so all I did was get a length of fuel tube and using larger diameter silicon tube plug it into one of the exhausts, the other end was attached to the vent pipe. 3 turns only of the prop and the carbs were primed, tube removed, on with the glow driver and she fired up - result! Needless to say that the motor ran fine, smooth as the last time I ran it and the model performed brilliantly, making up for the weather conditions! Quote Link to comment Share on other sites More sharing options...
Nigel Dell Posted July 21, 2022 Share Posted July 21, 2022 A little late to the party maybe, but have just got this from Jon, thanks Jon, spot the difference. Quote Link to comment Share on other sites More sharing options...
Nigel Dell Posted July 21, 2022 Share Posted July 21, 2022 Sorry two rubbish photos in there, here’s two better. 5 Quote Link to comment Share on other sites More sharing options...
alan p Posted July 21, 2022 Share Posted July 21, 2022 My pockets aren't deep enough but that do look nice😍 Quote Link to comment Share on other sites More sharing options...
Steve Dunne Posted July 21, 2022 Share Posted July 21, 2022 That's a good idea - having the carby in the exhaust port!😆 Quote Link to comment Share on other sites More sharing options...
Jon H Posted July 21, 2022 Share Posted July 21, 2022 7 minutes ago, Steve Dunne said: That's a good idea - having the carby in the exhaust port!😆 Customers try it all the time. I this case however, there is more going on.. Quote Link to comment Share on other sites More sharing options...
Nigel R Posted July 21, 2022 Share Posted July 21, 2022 matched pair for a twin? Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted July 21, 2022 Author Share Posted July 21, 2022 Clockwise prop direction. Quote Link to comment Share on other sites More sharing options...
Nigel Dell Posted July 21, 2022 Share Posted July 21, 2022 Well Nigel and Ron have it really, it as I am sure Jon will attest to was made to mimic the DH Gypsy in the reverse heads so the scale exhaust outlet is on the correct side but this goes one step further it is also reverse rotation, I think I am right in saying it is being called the Gypsy. lovely piece of kit. 1 Quote Link to comment Share on other sites More sharing options...
Manish Chandrayan Posted July 21, 2022 Share Posted July 21, 2022 18 minutes ago, Nigel Dell said: Well Nigel and Ron have it really, it as I am sure Jon will attest to was made to mimic the DH Gypsy in the reverse heads so the scale exhaust outlet is on the correct side but this goes one step further it is also reverse rotation, I think I am right in saying it is being called the Gypsy. lovely piece of kit. Is that the reason for the normal prop nut and the standard sleeve nut? Quote Link to comment Share on other sites More sharing options...
Jon H Posted July 21, 2022 Share Posted July 21, 2022 There is a little more to the story than Nigel has let on. When i originally envisaged the engine i did consider the situation with tiger moth's etc and the need to use reversed heads to get the exhaust out of the cooling air inlet and it was going to be called the gipsy edition, have scale rotation and all be brilliant. So, this gave me two potential engine configurations and 2 sets of timing. Great. However, interest in the gipsy ed was far greater than expected but most wanted it with standard rotation for ease of propeller choice and all that. This was fine i thought and off we went with pre orders recorded as 'gipsy ed' You can probably guess what happened next. As its been a while, i totally forgot that the gipsy ed timing on my cad drawing was for the reverse rotation and i had never worked out the timing for reverse heads with standard rotation. And, naturally, it was only when i picked up the reverse pitch 17x6 test prop (my brain remembered that part!) and fitted it to my test stand that the penny finally dropped. 'Oh dang and blast it, how spectacularly inconvenient' said i. Or at least, words to that effect. To save myself 2 days work, and a mental breakdown, i elected to run the engines anyway rather than stripping them and retiming them working on the basis that someone would want them eventually and it was quicker to just build more. Fortunately 2 of the 3 people who were in line for an engine from this batch were happy with reverse rotation and the 3rd engine had to come apart anyway as i wasnt happy with it and wanted to check it out. With that done and satisfied all was well i fixed my little gaffe as i had worked out the timing for a gypsy ed with standard rotation and it has departed to its new home. Not that anyone will remember but any engine marked GSR is Gipsy standard rotation and GRR is Gipsy reverse rotation. This is important as they look identical. in every other respect. To make life easier i may abandon the standard configuration engine as we do not need 3 variants of the same engine and the carb/exh position makes no difference in a warbird. 2 Quote Link to comment Share on other sites More sharing options...
Jon H Posted July 21, 2022 Share Posted July 21, 2022 5 hours ago, Nigel R said: matched pair for a twin? I tried to sell him another, but was told he might end up buried under the patio if he bought the 2nd. 1 Quote Link to comment Share on other sites More sharing options...
Jon H Posted July 21, 2022 Share Posted July 21, 2022 4 hours ago, Manish Chandrayan said: Is that the reason for the normal prop nut and the standard sleeve nut? Double nuts supplied as standard so you have both options available Quote Link to comment Share on other sites More sharing options...
Manish Chandrayan Posted July 22, 2022 Share Posted July 22, 2022 How can I get in the queue for a reverse rotation 200 in line Laser? Quote Link to comment Share on other sites More sharing options...
Manish Chandrayan Posted July 22, 2022 Share Posted July 22, 2022 7 hours ago, Jon - Laser Engines said: Double nuts supplied as standard so you have both options available On the reverse rotation engine, will the nuts be LH thread? Quote Link to comment Share on other sites More sharing options...
Jon H Posted July 22, 2022 Share Posted July 22, 2022 3 hours ago, Manish Chandrayan said: How can I get in the queue for a reverse rotation 200 in line Laser? At the moment i am not sending the inline's out of the UK as its just too complicated if there is problem. I already sent one out against my better judgement and it turned into a nightmare for all involved. Until the testing is finished and it is a standard stock item they are uk only im afraid. Quote Link to comment Share on other sites More sharing options...
Jon H Posted July 22, 2022 Share Posted July 22, 2022 3 hours ago, Manish Chandrayan said: On the reverse rotation engine, will the nuts be LH thread? No they will stay standard. Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted July 22, 2022 Author Share Posted July 22, 2022 36 minutes ago, Jon - Laser Engines said: At the moment i am not sending the inline's out of the UK as its just too complicated if there is problem. I already sent one out against my better judgement and it turned into a nightmare for all involved. Until the testing is finished and it is a standard stock item they are uk only im afraid. Makes sense! Quote Link to comment Share on other sites More sharing options...
Nigel Dell Posted July 22, 2022 Share Posted July 22, 2022 13 hours ago, Jon - Laser Engines said: I tried to sell him another, but was told he might end up buried under the patio if he bought the 2nd. Well this is true for now though it has got me thinking that I will look at ways of avoiding the patio scenario over the next couple of days! This motor is going to be tested in an airframe I had in storage, as you do 😳, it is an enlarged Frog Mustfire at about 85” would be a perfect test model, it did needed a lot of remedial work to be safe and true which is done, I am changing the fin and rudder to give the illusion of a tempest as this suits the wing shape and covering it in silver upper surfaces and yellow & black under sides target towing, no retracts it’s just too much work and I don’t trust the structure that has not been designed for the loads of retracts. just got to finish the engine install, make the cowl and finish the covering then we are good to go. The model this engine is destined for was one I drew up nearly 40 years ago and have not seen modelled much before if at all, my appreciation of between the wars racers the Miles M13 Hobby at 1/3 scale is not particularly large and I may increase it a little to around 90-100”, original powered by a DH Gypsy so that is appropriate, the reason for not continuing with the project was the lack of power plants at the time and the ST G4500 was just a pain to get in it, this is the engine it has always been waiting for. now the seed has been planted for the normal rotation engine as well the other projects I have always wanted to do are the DH 88 Comet but as Grosvenor House or Black Magic? That is the question 😂 or the Westland Whirlwind 🤭 Or do I wait for the 300i 🤔🤣am weighing up what’s best and more likely to be done to be honest but I am thinking about it! At least I am thinking about it!👍🏻 As to the prop availability for these reverse rotation engines, although not readily available off the shelf a call to Bernie at Jeti - Fiala UK has a selection of props ordered to be made in reverse rotation, and one at an increased pitch than advertised to cover all bases of course this is good because you can get the all as standard rotation as well, the cost is reasonable considering at between £19 and £25 each the standard will be slightly cheaper. also am fitting temperature sensors to the engine to fine tune the cowl baffles to ensure the cylinders run at least very close in temperature. Quote Link to comment Share on other sites More sharing options...
Jon H Posted July 22, 2022 Share Posted July 22, 2022 DH Comet with twin inlines....drool. But, if you go that route you will need another reverse rotation job so thats 3 engines i can chalk you up for as you need a matched pair for that, plus a 360 inline should i ever get it done....plus, a pair of 160v's for the whirlwind. Sounds very lucrative but the patio scenario could be a problem. That said, they would all look the same. Just make sure they are not all visible at the same time! Quote Link to comment Share on other sites More sharing options...
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