Jon H Posted February 15, 2019 Share Posted February 15, 2019 Posted by SR 71 on 15/02/2019 21:12:24: Wow who is that young handsom chap in the video, I had an image of a much older Jon Nice engine and soound everyone seems to assume im really ancient. Do i come across like a grumpy old man? if so thats probably not gonig to be a good thing in years to come Quote Link to comment Share on other sites More sharing options...
cymaz Posted February 15, 2019 Author Share Posted February 15, 2019 Really top bloke is our Jon....... Quote Link to comment Share on other sites More sharing options...
Nigel R Posted February 16, 2019 Share Posted February 16, 2019 That is a great noise! Quote Link to comment Share on other sites More sharing options...
Rich too Posted February 16, 2019 Share Posted February 16, 2019 Haha! I was expecting you to be much older too! That engine sounds awesome - love it. I can’t see how you restrained the model? Quote Link to comment Share on other sites More sharing options...
Jon H Posted February 16, 2019 Share Posted February 16, 2019 Posted by Rich too on 16/02/2019 07:47:49: Haha! I was expecting you to be much older too! That engine sounds awesome - love it. I can’t see how you restrained the model? I was going to get my restraint but the tail wheel got hooked on the wooden board and was very secure so i left it. I did hang on to it during high power runs though as i didnt think my parents would enjoy having it crash through the window of the dining room. Today i am going to cut the cowl to clear the exhausts, tidy up the glow cables and order the screws i need for the rocker covers. They are M2.6x7 which is a really stupid size. Thanks for that OS. I also have to do the valve clearances...on all 8 valves :'( In terms of performance though the thing is going to be a right beast. The prop was a 19x8 menz wood and she peaks at 7300rpm. thats a calculated 19.8lbs thrust and 2.8hp! i think it will be pretty speedy. Edited By Jon - Laser Engines on 16/02/2019 10:34:29 Quote Link to comment Share on other sites More sharing options...
cymaz Posted February 16, 2019 Author Share Posted February 16, 2019 Posted by Jon - Laser Engines on 16/02/2019 10:30:26: Posted by Rich too on 16/02/2019 07:47:49: Haha! I was expecting you to be much older too! That engine sounds awesome - love it. I can’t see how you restrained the model? I was going to get my restraint but the tail wheel got hooked on the wooden board and was very secure so i left it. I did hang on to it during high power runs though as i didnt think my parents would enjoy having it crash through the window of the dining room. Today i am going to cut the cowl to clear the exhausts, tidy up the glow cables and order the screws i need for the rocker covers. They are M2.6x7 which is a really stupid size. Thanks for that OS. I also have to do the valve clearances...on all 8 valves :'( In terms of performance though the thing is going to be a right beast. The prop was a 19x8 menz wood and she peaks at 7300rpm. thats a calculated 19.8lbs thrust and 2.8hp! i think it will be pretty speedy. Edited By Jon - Laser Engines on 16/02/2019 10:34:29 Hooligan Quote Link to comment Share on other sites More sharing options...
Jon H Posted February 16, 2019 Share Posted February 16, 2019 Me? never Quote Link to comment Share on other sites More sharing options...
Paul Marsh Posted February 16, 2019 Share Posted February 16, 2019 On the subject of glow drivers, I use the Sonic Tronics one, the best, although not cheap.. MacDanial Quote Link to comment Share on other sites More sharing options...
Jon H Posted February 16, 2019 Share Posted February 16, 2019 This engine is the first multi cylinder single carb engine i have used that really needs no on board glow. All of the ASP and saito efforts i have used needed it to keep them alight. If each cylinder had its own carb then glow is never needed but when they share a carb its impossible to match mixture so OS have done well here to keep the mixture pretty even across the cylinders. I ran the engine again today with the cowl fitted and was pleased with the results. The engine runs hot but happy and it didnt seem to mind a full 5 minutes at half throttle followed by a 20 second run at full power. It didnt falter at all and with the increased cooling it will see in the air i am very confident its going to work nicely. Quote Link to comment Share on other sites More sharing options...
TartanMac Posted February 17, 2019 Share Posted February 17, 2019 That engine sounds great Jon. It looks a great fit in the cowl too. I take it the Grey part on the cowl intakes are to deflect the air off the front 2 cylinders to keep all cylinders as close a temp to each other as possible? Looking at that crank you really must have worked some magic. I'm really curious how you dealt with the crank pins they look really bad. Also is that crank 2 pieces as I see there is ball bearings in the centre. Does the bearing hold it together? Very cool project that thing will be great fun in the air 👍👍 Quote Link to comment Share on other sites More sharing options...
Jon H Posted February 17, 2019 Share Posted February 17, 2019 Hi tartan The grey baffles direct the air up in to the top of the cowl. There is then another baffle at the back that prevents the air escaping and forces it all to go down, through the fins, and then exit out the bottom of the cowling. Its the same setup as used on full size lycoming and continental engines. The crank is a 3 part affair with the front section containing the prop drive section, front and rear main bearings (in the engine nose case) and then the two crank throws for the first pair of cylinders. The rear section contains the rear pair of throws, a journal for the rear bearing and the gear for the camshaft. Both sections are machined with flats on them and a joining sleeve keeps them together and supports the two middle bearings. For those keeping count its a 5 bearing crank using 3 different sizes of bearing. Fortunately the crank pins were not in a totally awful state and were cleaned up with some fine wet/dry paper. One thing OS recommend is that after each flying session the crankcase drain plug is removed and all oil in the crankcase drained out to prevent rusting. I have been following this procedure and the amount of oil that drips out is quite considerable. While the engine is running the drain plug is closed but there is a 2nd nipple for crankcase ventilation. I am super keen to get it in the air. I just need to get the rocker cover screws, a new rx battery and a sort out a few other small jobs and its good to go Quote Link to comment Share on other sites More sharing options...
Tim Flyer Posted February 17, 2019 Share Posted February 17, 2019 YMy Acrowot with its Laset 180 had its first three flights today. It was brilliant despite 24mph winds. It handled perfectly. I think this might be my new “go to “ plane . As I was running In i used the Just Engines Wood 18x8 prop but will later try their 18x 10 as per my Hurricane. The vertical with the 180 is totally enormous it just goes up. The plane required little trimming despite one warped aileron. The gusting 24 mph wind had very little effect. Jon’s very boring Laser 180 started first flick on all but one flight where it required two 😊. All I had to do before flying was leaning up the idle which needed about a quarter turn . I do that pre flying with a quick “ cowl off “ tune up to make sure all ok . I had moved the battery onto the firewall expecting my tail servos to unbalance the plane . I almost wish I hadn’t as I ended up adding 21g in tail weight to achieve the recommended balance point. It would be well worth Jon fitting tail servos on his plane 😊, even the he will need plenty tail weight ... maybe a tail battery !!😉 Edited By Tim Flyer on 17/02/2019 19:23:02 Quote Link to comment Share on other sites More sharing options...
cymaz Posted February 17, 2019 Author Share Posted February 17, 2019 Excellent report Quote Link to comment Share on other sites More sharing options...
Tim Flyer Posted February 17, 2019 Share Posted February 17, 2019 Cheers Cymaz I’m very happy.. it’s been worth burning the midnight oil for . I’m also pleased I got rid of the darn snakes and used tail servos. I would say it’s just as relaxing as the WWXL to fly and can do the low speed flying but the single wing makes it more practical and has a sharper performance. I will still enjoy flying both but i’m Certainly enjoying this ! Quote Link to comment Share on other sites More sharing options...
Jon H Posted February 17, 2019 Share Posted February 17, 2019 Nice work Tim. Good to hear the 180 has the oomph! i am really looking forward to getting mine in the air and i expect to do semi scale aerobatics with it. I really dont want to be ringing its neck, its just not what i am looking for. When Nick gets his done we should have a meeting of the wots up at the field Quote Link to comment Share on other sites More sharing options...
Tim Flyer Posted February 18, 2019 Share Posted February 18, 2019 .Cheers Jon . I’m really looking forward to seeing your 4cylinder in Action I’m sure it will be great an Acrowot Xl 4x4! That’s a good nickname for it 😊. I think it will be great fun having a formation Quote Link to comment Share on other sites More sharing options...
Jon H Posted February 18, 2019 Share Posted February 18, 2019 Sounds good to me. As the engine is unsilenced i dont know if it will be deemed too loud where i normally fly. From past experience its a little chrisp on the ground but in the air its not loud at all. We will see. If they dont like it then you are likely to see it quite often! Quote Link to comment Share on other sites More sharing options...
Nigel R Posted February 18, 2019 Share Posted February 18, 2019 Jon, must be some time sunk into baffling the cowl there! Is is just diverter pipes on the exhaust? Maybe some of those old OS style clamp on jobs that JE sell would sort it? I'm sure you've thought of that already. Quote Link to comment Share on other sites More sharing options...
Jon H Posted February 18, 2019 Share Posted February 18, 2019 Posted by Nigel R on 18/02/2019 11:14:20: Jon, must be some time sunk into baffling the cowl there! Is is just diverter pipes on the exhaust? Maybe some of those old OS style clamp on jobs that JE sell would sort it? I'm sure you've thought of that already. I had a few ideas with the exhaust but in the end went for the simplest option which was to solder some brass tubes into steel strips, bolt them to the airframe and connect the tubes to the engine with silicone. I am hoping the silicone can take the heat but only time will tell. I cant hang any load on the header pipes as they will just break. I found this out the hard way on my ASP radial. The baffles were time consuming but simple in design. I rejected my first idea as it was too complicated and just went simple again with the deflector plates at the front and baffle at the back sealing in the air and forcing it down through the fins. There is then a deflector plate on the outside of the cowl which creates an area of negative pressure in the outlet of the cowl and sucks the hot air out. Again, all of this is the same as used on full size cessna's and such so all i have really done is miniaturise it Quote Link to comment Share on other sites More sharing options...
Steve Dunne Posted October 14, 2020 Share Posted October 14, 2020 Hello all you Acrowot XL pilots - can anyone advise on the best paint to use to colour match the orange on the cowl? Preferably fuel proof, but if necessary I can add fuel proofer over a good colour paint. All this to save me the bother of longwinded colour mixing of fairly noxious paints! Many thanks, Steve. Quote Link to comment Share on other sites More sharing options...
Steve Dunne Posted February 19, 2021 Share Posted February 19, 2021 Well, I went the route of colour mixing and got a reasonable match. Now I need to repair some of the orange film covering. The model shops are closed to visitors so I can't go and look for a match. Does anyone know which film is a good match for tha Acrowot XL orange? Please? Thanks, Steve. Quote Link to comment Share on other sites More sharing options...
Jon H Posted February 19, 2021 Share Posted February 19, 2021 i think they are done in oracover but its not oracover by name. i would suggest calling ripmax, but you are more likely to get an answer from the wall. Quote Link to comment Share on other sites More sharing options...
Tim Flyer Posted February 19, 2021 Share Posted February 19, 2021 As Jon said it doesn’t seem to be Oracover. This is the nearest match(very slightly darker) I bought at Wings and Wheels a couple of years ago. It was unbranded Chinese covering but here is the label in case it helps . Quote Link to comment Share on other sites More sharing options...
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