Peter Miller Posted May 11, 2011 Share Posted May 11, 2011 Derek, That is very pretty. The owner of the full size flew over our flying field the other Sunday. It is remarkably quiet. Jim. I built one in 1954 but it was rubber powered. Never got it to fly. Quote Link to comment Share on other sites More sharing options...
Eric Mawman 1 Posted May 29, 2011 Share Posted May 29, 2011 Qestion for Peter Miller. At last i think I might be balsa bashing to build the Evans Volksplane from your plan No RC1456. I have the plan build extract from the RCM & E of 1983 but this has little mention of the tailplane construction. If I read the drawing correctly the way the 1" butt hinge is drawn no down elevator is possible or am I missing the point. Surely the trim tab is insufficient to have the effect of down elevator. If the hinge is opened to a right angle before fixing both up and down movement would appear possible. If this is the case presumably a bit of "beefing" up around the top spar will be satisfactory. Were there any updates in the RCM & E which I might have missed? Many Thanks Eric from Stafford. Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted May 29, 2011 Share Posted May 29, 2011 Hi Eric, Oh Dear, that plan is about 30 years ago. The hinge is in the closed position, not 90 degrees. I think you will find that most hinges actually close beyond that flat, well the cheap ones do. because it is so close to the leading edge it allows quite a lot of movement at the tail. Thinking about it, if you were to make two small wedges so that in effect the hinge is slightly open when the the tailplane is neutral you should get enough down even if the hinge is perffect.. The trim tab does nothing really it is just a working scale servo tab. Quote Link to comment Share on other sites More sharing options...
kc Posted May 30, 2011 Share Posted May 30, 2011 I have a part built Volksplane from Peters plan......I fitted a the elevator brass hinge to the ply former and fitted a piece of ply to screw the brass hinge to on the all moving elevator. The hinge is normally closed but I could find no bolts small enough at the time which would not foul each other to allow proper aileron movement. I now know there are sources for tiny bolts at the Model Engineer exhibitions etc. I did not trust just the tiny wood screws to retain the elevator so construction was halted 25 years ago. Just got the parts down from the loft and will photograph them if it helps you. Note that there are some errors in the plan, from memory the wing ribs dont fit the plan ie. the spars are drawn wrong distance apart. Sorry Peter I know its not your fault but the draughtsman's errors.. I complained to Bill Burkinshaw of the Plan Service ( that's how long ago it was! ) but even some years later the errors had not been corrected. Not a real problem but annoying........check first before cutting balsa. Quote Link to comment Share on other sites More sharing options...
kc Posted May 30, 2011 Share Posted May 30, 2011 Here is a photo of my incomplete elevator. The steel screws are just temporary to show you how it fits and are not fully driven home. The elevator is shown in a full up position so you can see the hinge. I think smaller countersunk screws driven right in will allow a certain amount of down elevator and plenty of up.Note that both parts of the hinge are fitted onto biirch ply parts and the horn also on ply. Not sure if the plans specifies ply. Could be tail heavy built like this. I wonder if proper model hinges might be better? Certainly liteply wiith countersunk bolts instead of screws might be better. The snag is access to nuts after covering if you use bolts. Captive nuts are not usually avail in such tiny sizes. Edited By kc on 30/05/2011 12:19:10 Quote Link to comment Share on other sites More sharing options...
fly boy3 Posted May 30, 2011 Share Posted May 30, 2011 Hi KC, could you not use normal Mylar strip hinges glued to the ply. Will save a lot of weight ?. Just a suggestion pal. Cheers Quote Link to comment Share on other sites More sharing options...
kc Posted May 30, 2011 Share Posted May 30, 2011 The hinge is built as per the Peter Miller plan. I guess Peter figured that the stress on a small area of hinge was too great and the pivot point also has to be high. There is only 30mm for the whole elevator hinge. Normally one would use 4 or 5 hinges along the whole width of a 390mm elevator. Just hitting a clump of grass with the tip would exert great sideways leverage on the centre of this model. Quote Link to comment Share on other sites More sharing options...
fly boy3 Posted May 30, 2011 Share Posted May 30, 2011 Quite right KC .Who am I to contradict the designer. Cheers Quote Link to comment Share on other sites More sharing options...
kc Posted May 30, 2011 Share Posted May 30, 2011 Actually its quite OK to suggest something especially as products have improved in the 30 years since Peter published this plan. If the mylar was just glued to ply it would certainly peel off with a sideways force. Inserted in between plys might work. The type of hinges that are inserted into drilled holes might work. However I feel the original might still be the optimum design bearing in mind that a sideways load on the all moving tailplane could snap a plastic hinge due to the leverage. I abandoned this project for several reasons including lack of confidence in the elevator hinge and the fact that when I saw a fullsize I realised how plain & ugly it was. At the time I suddenly realised my flying skill would improve by building a pattern model and several scale projects were relegated to the loft! Consequently if anyone who fancies a Volksplane but does not want to do all the balsa work wants to make me an offer...........Edited By kc on 30/05/2011 17:25:51 Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted May 30, 2011 Share Posted May 30, 2011 Thinking about the comments I have to agree that it was designed with what I could get hold of. If I was designing it now I would fit a block inside the rear of the fuselage and also the tail plane and then I would use two large Robart Hinge Points. Similar to the tailplane on the Luciole. The original model was flown on G-Mark 30 flat twin. Later it was fitted with a Fox 29 if I remember correctly. I had sold the G-Mark to a friend in New Zealand and on the last flight a con rod let go at full revs. The conrod was found to be porous. Irvine engines replaced it without any quibble. My friend got a brand ne engine at second hand prices. Quote Link to comment Share on other sites More sharing options...
kc Posted May 30, 2011 Share Posted May 30, 2011 Balsa block & the Robart hinge points sound a good idea but the actual pivot point as designed is level with the outside of the tailplane. So either one pivots it at a different place or the hinges have to be put in at an angle. Sort of vee shaped hinge when elevator is level. I don't think pivoting more in the centre would be a problem in flight. Any comments? Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted May 30, 2011 Share Posted May 30, 2011 Yes, the pivot points would be in the centre and that is fine. The only reason that they were on the edge was the shape of the butt hinge being used. It will not make any difference apart from the fact that you will get all the movement that you want up and down now and it will be lighter. Quote Link to comment Share on other sites More sharing options...
kc Posted May 31, 2011 Share Posted May 31, 2011 Having dug out the plan which I bought in the 1980's I see that the errors I remembered are more on the wing ribs.Anyone who is building from the plan should note that ( unless the plan was altered after I bought mine ) the rear spar cutouts in the ribs do not fit the spars. The spar is 3/8 x 1/4 and the slots are drawn much larger , so cut the slots to suit spar not the plan. Also R2 to dotted line should read R3 and the quantity is 12 not 8. Very frustrating if you cut a pack of ribs and then find you did not make enough due to wrong quantity specified on the plan! Actually quite a nice plan and well detailed.If you are building this plan then it's also worth looking at Peters much later models to see his aileron servo linkage drawing which would work well on this and save all the worries I had connecting the pushrods. ( I am referrring to Peters recent 2 wires and a quick link all soldered into a brass tube in many recent free plans ) Edited By kc on 31/05/2011 11:08:34 Quote Link to comment Share on other sites More sharing options...
Eric Mawman 1 Posted May 31, 2011 Share Posted May 31, 2011 Peter Miller. Thanks for a speedy response and yes the plan may be old but its like me!! Its a model Ive always liked the looks of and as far as I know no oneone in the club has one. From a rough sketch it seems the wedges you mentioned will do the job but I shall build a small mock-up to see the result first. Thanks also to the comments from others about their experiences with this model. Eric from Stafford Quote Link to comment Share on other sites More sharing options...
kc Posted May 31, 2011 Share Posted May 31, 2011 I think that Peter's suggestion of Robart Hinge points is a better solution nowadays. And lighter because you dont need a ply former only balsa. Wedges mean the screws need to be longer or go less far into the ply. Angling the whole rear former would be easier! Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted May 31, 2011 Share Posted May 31, 2011 I definitely like the Robart Hinge Point idea best having tried it onthe Luciole. Sloping the former is an idea I hadn't thought. The wedges will work. Interesting how ideas can be generated. It is one of the things I love about modelling, coming up with new ways of doing things. Wait until you see my new undercarriage! Quote Link to comment Share on other sites More sharing options...
Eric Mawman 1 Posted June 12, 2011 Share Posted June 12, 2011 Made a mock up and the wedges (3 degree engine/engine mount wedges) have given sufficient down elevator. Having re-read the comments the final result is still in the air. (no pun intended) but I will see what hinges etc may be available at Weston next weekend. Eric . Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted June 12, 2011 Share Posted June 12, 2011 Glad that you are getting it sorted one way or another. Quote Link to comment Share on other sites More sharing options...
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