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John Minchell

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  1. John Minchell
    Don't think so, but for clarification please email contest director Chris Allen on [email protected]
  2. John Minchell
    The Scale Nationals will be held at Buckminster on August 14th & 15th for RC, CL and FF. STC are just working out the details over the next couple of weeks.
  3. John Minchell
    One thing I have heard of (over on another stick and tissue forum - HPA) is that 1/16 balsa sheets can be cut using multiple passes on a silhouette cameo to make all the rib or former parts for small lightweight rubber or CO2 models. Opens up the possibility of all those old Keil Kraft and Veron flying scale models to be made from decent wood and your own accurate parts set if the kit isn't remade by VMC or another laser cutting outfit. John M
  4. John Minchell
    Thanks all - enough there for me to figure something out.
  5. John Minchell
    What is the usual fuel tank size people put in their models for say a 40, a 60 and a 120 size glow 2 stroke to give enough time for a full schedule and a bit spare for an aborted landing and go around again? John M
  6. John Minchell
    Steve It definately is not an Algebra, fuselage on the wooden one (800 or 1000) is totally different (rolled Ply) and the tailplane is all moving and sited 1/4 way up the fin from solid 3/8" balsa sheet not built up. Otherwise Algebras has sheeted foam wings and glass moulded fuselages. John M
  7. John Minchell
    Denis, all models which are competition ones or have a large bill attached, will not be using a Bec ESC or a stand alone UBEC like this one. They will all have separate Rx supply battery and the main power LiPo will only get used for the motor. I will now only trust Becs in cheap foamys and maybe F5RES 2/3 channel glider etc. I wasn't advovating cutting off all the heatshrink - only a section at both ends to allow airflow through, but maintaining the electrical insulation.
  8. John Minchell
    Thanks for the replies guys - the jumper is indeed on the 5.5v pair of selector pins and was always in that position in use, as I have some servos which are only 6.0v capable as well as the HV ones that the UBEC took out. My MPX Rx is safe to 12v but receiving 25v was too much. The fingered heat sink is totally covered by the heatshrink plastic as supplied - preventing any through airflow and there is substantial carbon dust and "ash" type residue on the inside of the heatshrink which is where the component blew and failed. I am now better educated and will take a scalpel to all ESC's heatshrink that I am using the BEC on to power the radio and allow air flow through the fins inside the heatshrink or across the plate type of heatsink. Whether overheating was the cause of this one blowing I will never know, but nothing got overly hot (I checked with a temprerature sensor under the canopy and there are fuselage inlet and outlet airflow holes) as the climb was 30 to 45 seconds or so followed by gliding for up to 30 minutes on the task. And of course the UBEC was powering the Rx servos for the whole flight.
  9. John Minchell
    I had a 4 Max 20amp UBEC installed in my large Valenta Thermik XXXL 5m electric soarer for GPS Triangle racing. I wanted to save the weight of a separate Rx / servo battery and this looked like a good option, without relying on the BEC in the ESC which would not handle the 10 servos in the model. It was fine for about a dozen flights, but has now failed. Instead of failing and not passing any power through, it failed and passed the full 6 cell LiPo voltage (25v fully charged) through to the Rx and servos. It has unfortunately fried my RX12 DR Pro Multiplex dual receiver (£260) and taken out the two digital servos in the fin (£100+), fortunately I did not have the wing attatched with another 8 servos in it. The specs of the UBEC are 3 to 12 LiPo input and 20amp output (8 to 12 servos). I have spoken with George at 4 Max about it and he says it is the first one he has heard of which has failed. I just wanted to advise anyone using this unit to keep an eye on it and check its output before connecting it and risking an expensive model or equipment. Or to do as I will now do and carry the weight of an additional Rx/servo battery. In closing I have a number of other 4 Max products and they are performing ok, so this is extremely disappointing and expensive when you are on a tight budget. Pics show failed component after I removed the heatshrink covering. John M
  10. John Minchell
    Hi Don - no it wasn't me, but I have a good mate who is sending me a new, unrun ASP 120 with silencer for £50. I thought that was more sensible than a used and possibly abused engine from ebay. Thanks for your help. John
  11. John Minchell
    Thanks Don - dunno what I'll do yet, it depends on what motor I can find at the right price etc. As I say I have a brand new in box Super Tigre 2500,but it's way too heavy. As long as a good 120 or 108 2T will fly the model, then hopefully I can find something cheap but a good runner.
  12. John Minchell
    Thanks Don - gives me something to go on. What size & pitch prop does the ASP 120 turn? John M
  13. John Minchell
    I have a 72" span Maxim model which used to fly with a 20cc fourstroke glow motor - YS / Yamada or something. I aquired the model without servos or motor. I wanted to put a spare ST2500 in it but with 6x standard 60g servos and a motor weight of 1.2kg it will put the OA weight to 5.3/5.35kg which is over the limit for your UKCAA competitions. Does anyone know the weight of say a 120 ASP or SC or some such similar 20cc 2 stroke motor (with and without silencer) which I can get hold of easily (money is tight too, so likely second hand) and with some 30g servos I can squeak under the 5kg limit? TIA John M
  14. John Minchell
    I thought the Solarfilm company had stopped trading? John M
  15. John Minchell
    Colin I spoke with Paul and he has seen your email - he's rushed off his feet with Xmas sales stuff but will reply to you as soon as he can. John M
  16. John Minchell
    Have you seen the latest Scale Newsletter I sent out Colin? You and your PFM Zlin get a mention. John M
  17. John Minchell
    Try the Practical Scale one from Toni Clarke in GDR, might be the right size. John M Edited By John Minchell on 25/09/2020 12:43:56
  18. John Minchell
    To be honest Mark you could make the nacelles in 1/8" sheet top and bottom with a wide 1/2" or 3/8" sheet profiled piece to give gluing area to the wing skin and some triangular 1/2" in the corners to hold the sides to the top and bottom. With a proper birch ply engine bulkhead, tied into the corner triangular reinforcements, that's about all it needs. That would save a couple of hundred grams. John M
  19. John Minchell
    Mark if you are a bit worried at the strength of the tail v join you could put a glassfibre bandage reinforcement (like joining trainer foam wings) and keep it narrow inside the fuselage. John M
  20. John Minchell
    Hysol 9466 is still epoxy, just a more modern recipe. John M
  21. John Minchell
    Danny / Mark The plan says "hardwood not ply". Mine is two pieces of 1/8" bass wood cut from 1/8 sheet and laminated with epoxy before gluing into the 3/8" balsa sheet tailplane halves. John M
  22. John Minchell
    Tom Tom what does that mean? I have not used anything pre-populated, just put my own name & postcode etc and got the message i posted up yesterday.
  23. John Minchell
    Tried again Barrie but here's the message I get. John M
  24. John Minchell

    John Minchell posted a gallery image in Member Albums

  25. John Minchell
    Thanks for the swift reply Barrie - but I did use the first link, so I am not sure what the problem is. Regards John M
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