Jump to content

stu knowles

Members
  • Posts

    829
  • Joined

  • Last visited

  • Days Won

    3

Posts posted by stu knowles

  1. I need a bit of help with a OTX Mixer.    I have set up a twin engine (I.C.) mixer,  Each engine has a separate channel. Using a three position switch I have

    1. No Mix

    2. Throttles mixed with rudder. Full rudder adds 5% to one engine and subtracts 5% to the other.

    3.  As 2 but 10% added / subtracted.

     

    This was added to the model because it has a tendency to swing to the left on take off but is also good for taxiing.

     

    The problem is when taxiing the engine which has the throttle reduced often moves into the zone where the engine stops.  If I add a few clicks of throttle first all is well but in the heat of the moment this can be forgotten resulting in a stoppage.

     

    Is there a setting in OTX where if switch position 2 or 3 is in use it wont drop the throttle channels below a preset number or even the number used in the throttle trim setting??

     

    Thanks 

    Stu K

     

     

  2. I've never found a source of 3mm studding with a left hand thread.  I did find some welding wire in just the right diameter to take a LH 3mm die.  I have also centre drilled some 6mm alloy bar and tapped 3mm Left and Right into opposite ends.  It works but 3mm taps are very brittle.

     

    Carbon arrow shafts are useful, not sure that I've seen an alloy arrowshaft.

  3. That looks fantastic!

     

    I too had a dabble with Corrox year ago.  Made a horrible looking but very robust trainer.  It flew fine but I couldn't live with the appearance and wrote off Correx as a building material.  Next stop will be the beginning of this thread to learn how you have done it.

     

    Any thoughts on putting the STL files of somewhere like Thingiverse?  The Tip Tanks look very handy  😉

    • Thanks 1
  4. Gorilla PVA as I recall is very thick consistency compared to many PVAs. I use PVA from a 5 litre bottle from the Builders Merchant which is really used to size walls and plaster.  I imagine that cheap 'Pound Shop' PVA will be better for this purpose than best quality wood glue.

     

    Chris Golds was  probably the pioneer of BP/PVA covering.  If you read up on his methods he pastes the brown paper and the wood surface.  Lays on the BP and does all the trimming (make sure that both sides of the wing/control surface or whatever are done together or shinkage will cause a warp) and then he pastes both sides again and hangs it up so that both sides can dry evenly.  Since Ron did his video I have tried his method and its good too, a lot less prone to mess.

     

    I think that the bottom line is that BP and PVA covering can be applied using slightly differing methods to get the same result.  From my experience the key points are to lets the BP 'ease' for  few minutes after pasting but before applying to the model and always do both sides together.  The PVA can be used quite liberally and doesn't cause significant weight gain.   

     

    If you are getting bubbles use more paste and let it stand a couple of minute to relax before applying to the wood.  If you don't believe that the paper shrinks as it dries just apply it to a single side of a 1/4 balsa tailplane and see how much of a bananna has arrived in the morning.  If the PVA has been applied liberally a hot iron will stick down bubbles and loose ends.  The paper is likely to bubble soon after being applied but before it has dried.  If this happens give it a little longer to ease before applying to the model but in any event, DON'T PANIC.  Leave it to dry.  Most bubbles will shrink away as it dries and a light iron will deal with any remaining.

     

    Chris Golds also applies two or three coats of the PVA paste all over after the first application with sanding in between to prep the model for paint.  If you have a persistent bubble, tear, not cut it open, apply paste and brush it back down.  Torn edges disappear more easily than cut edges.

     

    I have covered several models with BP.  Its cheap, light and non critical in its application.  With practice I don't exit the covering session quite so tarred and feathered with off cuts of brown paper as I did in the beginning.  Its  a perfect method for any all sheet airframe like the 190 or Tempest subject of this thread.

  5. Seems like a good and simple way to start with a single panel and cut it to finish up with a dihedral break at mid span.   Would it be more certain of good alignment if the dihedral brace slots were cut in before the single wing panel was cut in half?

     

    Is the order book still open for the Tempest??  I've been impressed by the Wulf and this one is shaping up so well.  It needs one to be built with a good glow engine!

    • Like 1
  6. Hello Ken,

    As I remember its around 38lbs and is powered by a Zenoah 80cc twin.  The wings come off as a pair so it assembles with four 6mm bolts and four 3mm nuts and bolts so its quite a quick and easy rig.  Trouble is that it takes up an enormous amount of space.  I have to transport the fus in a trailer and the wings are carried in the car - a large estate.  It uses the basic four channels plus a switchable landing light, a Royal Navy flag which raises and lowers out of the rear cockpit as used in the RN Heritage Flight and the middle crewman raises his arm in a 'Thumbs Up' on a low and slow fly past or when taxi ing.  Since the photos I have added a non droppable torpedo and a 3D printed dumy engine which sets it off a treat .

     

    It would be really nice with something like a 150cc radial on board but thats unlikely on my watch.  I don't fly at shows which would be its natural environment and physically lifting it into and out of storage is becoming a problem due to advancing years.  I'd like to fly it again when the weather improves  but its likely to be moved on this year

    fish3.jpg

    • Like 4
  7. Believe it or not I think that this 120" version is basically a scale up of the same plan,  Not built by me, it came a a bit of a wreckto be rebuilt.  Beautiful steady flier,  it perambulates around the sky in a stately manner as befits the real thing

    fish1.jpg

    fish2.jpg

    • Like 7
  8. I have one of those, the blue one, which has been fine for ages and then it started playing up yesterday in exactly the way that you describe. All three lights on and poor / nil servo control.  It's the same today and is on my job list for tonight to look on line and find a new one.

     

  9. I always thought that the ground looping tendencies of vintage models stems from the very forward wheel position??

     

    Lovely finish and colour scheme on the model although if t'were mine I would re think the bolted on struts.  So slow and fiddly, the  assembly / dis-assembly will discourage frequent and regular outings.

     

    Nice model and a good looking design.

     

  10. 20 hours ago, Nick Cripps said:

    I didn't think the rain in the last few days was enough to cause further flooding but the ground here in the Trent Valley has been saturated so much during these winter months that our flying field was again under several inches of water. Our starting benches floated off to one edge of the field a few weeks ago and are now inaccessible without a boat(!), and the storms a couple of weeks ago ripped the covering off the work benches.

     

    Despite all that, I again took advantage of the good weather today to get the waterplanes out for a great day's flying.

     

    PXL_20240224_105720893.thumb.jpg.4793cdcbd1a3beb3e5624e0ded70f3e5.jpg

    Our field is wet Nick but you win hands down with that one.  Perfect for Waterplaning though

  11. There was a guy came to our club with a GB ish type racer, from the same era, huge engine and not a lot of wing.  He had built the fus at 1/4 scale and the wing at 1/3rd.  Only someone very familiar with the original would have known and it flew very well.

     

    Maybe a moment for a bit of artistic licence?

  12. You can be very proud of  that build and finish,  Anyone would be happy with that..  And the best bit - there isn't another one just like that anywhere in the world

  13. Yes it is!  It really brings an airframe to life.   Years ago, Ian Peacock did a 'Dogfight Double' in one of the mags  RCM&E or Radio Modeller, I forget which, but it was to me at any rate, a revelation how he brought panel lines and weathering onto a plain airframe which added so much to the realism.  Easy to do and next to no cost, I thought it to be a leap forward in how to build and present models.

     

    Ian was followed by Chris Golds who took the ideas to another level with his models.

     

    Richard, Dave and Ron ( and others) are really showing the way with these builds

    • Like 2
  14. Hi to ALL

     

    Thanks for looking in.  Does anyone have to December 2000 issue of Quiet & Electric flight??
    If anyone can help I'd be pleased to hear from you, either to buy the mag itself or for a copy or photograph of the pages of the plan review inside.  Its the Gigant glider by Chris Golds.

     

    Thanks

    QFI.jpg

  15. There was a vid doing the rounds a few years ago of a scale German WW2 three engines seaplane flying alongside a MPX Twinstar, both FPV equipped.  Even though it was the early days of FPV they were very good at flying in formation and station keeping.  (Goodness knows how much practice they had had).

     

    Your vids show lots of promise, I guess that you will be removing the canopy hoop to give you  a better field of view?  I have always thought that FPV flying with fixed wing would be a very popular extension to the hobby but it hasn't really caught on.  Please keep posting your vids and let us know what equipment you find best to use.

     

    Wishing you success!

    Stu

    • Like 2
  16. I did some trials with white polystyrene fom cores covered with brown paper and PVA. Some local glasscloth reinforcement, all of which worked to a greater or lessor degree.

    One had 1/4 square balsa top and bottom spars let in before covering, another had carbon tow 'spars' top and bottom and another had the BP covering overlaid with 50GSM glasscloth & epoxy.  They all flew well.  From memory, the lightest had the carbon spars and just BP/PVA stressed skin.  The only balsa was the leading edge and a hinge spar.  No veneer at all

    • Like 2
  17. On my past models I have found a slight tendency for the brown paper to lift and curl away from the cut edges around the servo bay for example. Anywhere where there isn't the overlap.  I now iron a narrow strip of scrap solartex around the edges of the openings and try to wrap it around inside.    The peel back has often not shown itself for a year or so, I guess it could be that the edges are more vulnerable to absorbing damp from the atmosphere?

     

     

     

×
×
  • Create New...