Stephen Belshaw Posted December 1, 2021 Share Posted December 1, 2021 As a perennial "glider guider" and principally slope, encompassing sport, scale and PSS I now find myself with flat field flying as my only option. On paper Peter's T31M fulfils all my new found requirements in being a scale glider, but with a motor and of a size that should suit my smallish airfield. I bought the laser cut kit, wood pack and plans from Sarik Hobbies and sourced the remaining bits from multiple sources to give me the following specification: 4-Max P0-3547-800 brushless motor 13 x 6 wooden prop YEP 40A ESC 2200 3S LiPo Hi-Tec HS-81 servos for ailerons, elevator and rudder HobbyKing micro servos for air brakes The construction of this, to me, looks more like a powered model than a glider so it'll be a bit of a learning curve with undercarriages, steerable tailwheels and dummy engines all unfamiliar territory. I also intend deviating from the plan a little by mounting the aileron servos outboard in the wings, moving the rudder servo under the cockpit and utilising a ball link connector for what will be a removable tailplane ( the accompanying photo should explain). I've started by separating the laser cut parts from the sheet to make a "kit", laying everything out on the plan to understand the construction and will be using Peter's magazine article as a build guide. I have also knocked up a motor mount incorporating the required side and down thrust. Kit of parts: Motor mount: Proposed elevator linkage, this will be inside the fuselage rather than the outboard ones in the original design: I've made a start on the fuselage sides, this will be followed by the forming of the undercarriage and wing supports, not a job I'm looking forward to! 1 Quote Link to comment Share on other sites More sharing options...
EarlyBird Posted December 1, 2021 Share Posted December 1, 2021 ? this looks interesting. Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted December 1, 2021 Share Posted December 1, 2021 IT is a lovely model. Funny...I don't remember incorporating any side or down thrust! Quote Link to comment Share on other sites More sharing options...
EarlyBird Posted December 1, 2021 Share Posted December 1, 2021 1 minute ago, Peter Miller said: Funny...I don't remember incorporating any side or down thrust! That did surprise me. I thought that has to be the first and only time.? Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted December 1, 2021 Share Posted December 1, 2021 It is amazing how people seem to think that every model has to incorporate has to incorporate side and down thrust. I have a very simple question. Does the full size have side and down thrust? People tell me that you need side thrust to counteract torque. In that case I suggest that they fit a working rudder. I have seen piston engined fighters with off set fins but never offset engines. Of course If you are building a free flight model that is different,Possibly! Quote Link to comment Share on other sites More sharing options...
Stephen Belshaw Posted December 1, 2021 Author Share Posted December 1, 2021 1 hour ago, Peter Miller said: IT is a lovely model. Funny...I don't remember incorporating any side or down thrust! Yes, full of character. I wonder where I got the side thrust idea from - I'll go back and check the plan ............ Quote Link to comment Share on other sites More sharing options...
Stephen Belshaw Posted December 1, 2021 Author Share Posted December 1, 2021 Just back from checking the plan: Now what?! Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted December 1, 2021 Share Posted December 1, 2021 IT would seem that you are right. It must be the first...and last model on which I had those thrust setting. I must apologise. Quote Link to comment Share on other sites More sharing options...
Stephen Belshaw Posted December 1, 2021 Author Share Posted December 1, 2021 No need to apologise Peter, but given the other comments should I incorporate the side/down thrust or not bother with it? Quote Link to comment Share on other sites More sharing options...
kc Posted December 1, 2021 Share Posted December 1, 2021 (edited) The article is in RCME Feb 2010 page 90 says " don't forget to build in the side and downthrust..." The peril of the digital archives is it's always there! That is if you are a subscriber! Edited December 1, 2021 by kc Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted December 1, 2021 Share Posted December 1, 2021 . I am now more puzzled that ever. You see I designed two T31Ms. The first was for a speed 400 motor published in Flying Scale models A Model of G-BOOD. I have just been looking at this plan. Then I designed and built a model f the SAME aircraft of an OS 40 FS. The ne with the Speed 600 motor has 2 degrees f down thrust and NO side thrust. The second puzzle was that the section of cowling shown was nothing like like my cowl which covered an inline engine with no bulges n the sides and no visible engine. I have now solved the mystery. You are building the Keith HUmber version. NOT Mine. For some reason my filing system has let me down and while I can find the FSM article and plan and I can't find the OS powered one at the moment Quote Link to comment Share on other sites More sharing options...
Alan Gorham_ Posted December 1, 2021 Share Posted December 1, 2021 Sarik are crediting this design to you Peter (see link). It does have a flat 4 engine and the (albeit small) picture of the plan and cutaway of the model matches what Steven is building. https://www.sarikhobbies.com/product/slingsby-t31m-plan/ Is it possible you have designed this one too? It look like it was published in the Feb 2010 RCM&E and I thought Keith Humber contributed to RC Model World predominantly? Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted December 1, 2021 Share Posted December 1, 2021 This is the link to the Kirby Motor Tutor on the Sarik site https://www.sarikhobbies.com/product/kirby-t-29-motor-tutor/ Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted December 1, 2021 Share Posted December 1, 2021 Look at the cowl and registration Quote Link to comment Share on other sites More sharing options...
Alan Gorham_ Posted December 1, 2021 Share Posted December 1, 2021 Yes but this thread is about a T31! Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted December 1, 2021 Share Posted December 1, 2021 This is the plan of my T31. The electric powered one but the larger ne is the same aircraft. Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted December 1, 2021 Share Posted December 1, 2021 Mine is a T31. Check photos of T31s G-BOOD gn Google Quote Link to comment Share on other sites More sharing options...
Alan Gorham_ Posted December 1, 2021 Share Posted December 1, 2021 Steve, the topic originator will be able to help solve this condundrum by posting a pic of the designers name on the plan. He has already stated though that the design has been credited to Peter Miller and from what I can see from the plan pics, it's definitely drawn in the RCM&E house style. That makes me think it is one of your designs Peter, but no wish to get into an argument and happy to be proved wrong. It's also possible I guess that the RCM&E draughtsperson has added the thrustline offsets because they think 2 degrees right and 2 degrees down is some kind of standard. Which would be a naughty assumption on their part, whoever designed the plan! Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted December 1, 2021 Share Posted December 1, 2021 Quote You would be amazed at some of the "assumptions" the draughts person makes Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted December 1, 2021 Share Posted December 1, 2021 Alan just compare the plan views of the cowling on my drawing and yours Quote Link to comment Share on other sites More sharing options...
Alan Gorham_ Posted December 1, 2021 Share Posted December 1, 2021 Its not mine! It's Steve the original posters plan. I am simply saying that you have designed more than one variant of the T31. the image you posted was a plan you did for ADH/Doolittle or whatever they were called then. The plan under discussion here was done for RCM&E. Interstingly, the blurb with the plan says this, which suggest that whioever designed it (Sarik are saying it was Peter Miller) had previously designed and electric version and one powered by on OS40 four stroke. Sounds familiar!). "So much for full-size history, then; what’s the background to this model? Well, several years ago I built a 73” span electric-powered T31M for an acquaintance who flew gliders and vintage models but wanted something a little more advanced. It was a lovely model to fly and inspired me to build one for myself around an old pre-Surpass O.S. FS40. I based my model on G-BSHM (now PH1121) because I liked the look of the angular front deck and its colour scheme. The result is a model that’s accurate in most respects, save for a couple of omissions: I wasn’t sure whether ‘HM has the spoilers that are fitted to some T31Ms, so I didn’t put any on the model – which makes the build easier, of course – and the cowl has been simplified slightly by omitting the bump that hides the self-starter. Building the model is quite straightforward – very much like a vintage design, in fact – indeed the only area that calls for care and great accuracy is the strut assembly and wing mounting, but we’ll come to that in the fullness of time." Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted December 1, 2021 Share Posted December 1, 2021 Both my T-31s where this aircraft in this colour scheme. I even got photos from the owner of the full size. THat bulbous cowl has nothing to do with me or my model and it was never sown on my plans and I would have complained bitterly if it had Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted December 1, 2021 Share Posted December 1, 2021 PS I can even supply accurate scale drawing of the fullsize. Quote Link to comment Share on other sites More sharing options...
EarlyBird Posted December 1, 2021 Share Posted December 1, 2021 From the archive article. I don't understand the confusion. This is what Sarik are supplying from RCM&E. I take it that being a high winger 2 deg of down thrust is needed, looks like it in the photo above, but side thrust is not needed? Quote Link to comment Share on other sites More sharing options...
Alan Gorham_ Posted December 1, 2021 Share Posted December 1, 2021 The confusion is that Peter is saying he didn't design this model. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.