Plummet Posted December 31, 2011 Share Posted December 31, 2011 OK, I am starting work. I bought the plans and bits from D.B. Sport and Scale. By bits I mean wing ribs, the dural cabane struts, dural undercarriage, and wheels. I also opted to buy their 'patterns'My work, (not counting trying to tidy my cellar workshop, put move various tables round the house so that I could put one in my workshop) started with the patterns.These are printed sheets with a removable backing to allow them to be stuck to a suitable sheet material in order to make templates for various parts. Here you can see that I have stuck the two sheets of patterns onto 3mm mdf, and have used my scroll saw to cut the parts from one of the sheets. These are sitting on a green cutting mat. Comments so far? A slight quibblette. The parts are labeled only with the number required and the material to be used. In some cases it would be useful to also identify which part it is. I have gone through the ones I have cut out and identified them from the plan. This task is slightly complicated because the patterns have metric wood thicknesses and the plans have imperial ones. I would strongly recommend anyone building this model to get the patterns from D.B. S&S as seeing the bits, and hunting for where they go makes the plan a lot clearer. In particular, there is a bit in the centre of the tailplane that I had failed to realise existed from my earlier plan gloating. As far as I know, I have not displayed my typical degree of incompetence yet. There is plenty of time for that. My build has started. Plummet Quote Link to comment Share on other sites More sharing options...
Kntt Posted December 31, 2011 Share Posted December 31, 2011 Always fancied one of these and i had my eye on the plan and rib pack for a while now.Keep us posted on how it goes, i may treat myself to one.Kent Quote Link to comment Share on other sites More sharing options...
kc Posted December 31, 2011 Share Posted December 31, 2011 I assume the MDF is just for a permanent pattern to copy again onto the ply or balsa? ( has anbybody ever used MDF for flying models! ) Quote Link to comment Share on other sites More sharing options...
Plummet Posted December 31, 2011 Author Share Posted December 31, 2011 Perhaps I am just a pessimist. I suppose that I could have stuck the patterns onto ply or balsa, but if I did that then I would be sure to need the shapes again for repairs. Since I have gone to the effort on making the templates I can only assume that I will never need them again. Unless I end up building a plague of Barnstormers that is... After all, I do have three Webbits down there. Or put it another way, no I am not building an MDF Barnstormer. I suspect that MDF does not have aeronautical tendancies. Yes it is flat, and can be cut into silly shapes, but it is quite brittle, quite heavy, and does not handle moisture too well. Plummet Quote Link to comment Share on other sites More sharing options...
Kntt Posted December 31, 2011 Share Posted December 31, 2011 I would make at least 3 of every thing then as you say you can have a plague of Barnstormers. I had as you say a plague of Flair Hooligans because I made plenty of everything the first time round. I have had a look at the web site and I think I will go for the slightly larger 72 inch with electric power. There is a good ink to the 4-MAX site giving recommended of motor and cell combinations if you were thinking along those lines. www.4-max.co.uk/dbss-barnstormer72.htm Kent Quote Link to comment Share on other sites More sharing options...
Kntt Posted December 31, 2011 Share Posted December 31, 2011 motors for barnstormer Try again with the link Quote Link to comment Share on other sites More sharing options...
Plummet Posted January 2, 2012 Author Share Posted January 2, 2012 I'm compiling a shopping list for my build. The main wing spars are shown on the plan as 1/4 square, but there is no indication that they are anything other than balsa. I have been footling around with my stocks of balsa and all my 1/4 square feels too flexible for the job. I am wondering if I should laminate the balsa with some carbon fibre tow, make the spar out of a balsa/spruce sandwich, or just use spruce. The wings are each 30 odd inch in span, and are of the usual D box leading edge including the spars, sheeted with 1/16th sheet. The structure behind the main spars is open, with an extra lower spar towards the trailing edge. Advice and/or comments would be appreciated. Plummet Quote Link to comment Share on other sites More sharing options...
David Hodgson Posted January 2, 2012 Share Posted January 2, 2012 Assuming the top and bottom spar have ve reticle webbing between them and sheeted top and bottom then balsa should be fine for a wing that size. I can't remember ever seeing a barnstormer wing fold.If you really want piece of mind use spruce for spars. Quote Link to comment Share on other sites More sharing options...
Plummet Posted January 2, 2012 Author Share Posted January 2, 2012 Ta for that. I will look out for some nice hard balsa strip for the spars then. Plummet Quote Link to comment Share on other sites More sharing options...
Plummet Posted January 10, 2012 Author Share Posted January 10, 2012 In another thread I have been investigating making paper translucent. Why? Well the Barnstormer plans only show one wing. To make two wings my thinking said that I would need to either take a tracing of the wing, or turn the plan over after making it a bit transparent. My experiments were quite successful and so my plans are now coated with silicone lubricant, and look like greaseproof paper. I can see through the paper, and I hope that the silicone will stop glue sticking to the paper. However, having done that I have discovered that I need not have bothered, as Eddy, from D B Sport and Scale has pointed out that the wings are symmetrical end to end, so they can both be build over the same plan. I must just remember to stick the two wingtips on different ends! And while I think about it, I must confirm where the thicker wing ribs go. So I should be able to dribble some aliphatic soon - but not tomorrow! We have to hit the motorways for 'family duties'. Plummet Quote Link to comment Share on other sites More sharing options...
Big Bandit Posted January 15, 2012 Share Posted January 15, 2012 Hi Plummet, I like the idea of making templates from MDF, it's a much cheaper option than using ply as I normally do. Cheers, Chris. Quote Link to comment Share on other sites More sharing options...
Plummet Posted January 20, 2012 Author Share Posted January 20, 2012 I am a slow builder. I like to use aliphatic glue, and to leave joints to set overnight when I can. (Life also gets in the way as well.) Anyway, I have finished the first side - and made my first mistake. These build blogs are here, I hope, to help anyone else who is building the same model. So it is only fair to admit to your mistakes in order to help others. Here is the side as built. Closer up you can see a gusset (No oooh errrr Mrs comments please!) I hope you can see a couple of things here. The first is that the sheet piece on the LHS has to be cut from a wide piece of balsa. I glued two 3" wide sheets together tor these pieces. The rest of the sheet can then be used for cutting strips etc. Secondly you see the triangular gusset that strengthens the joint between the fuselage side bottom and the lower longeron. It should not be there! There is a former that needs to go there first. I am going to have to cut it out again. No real problems with the build so far - except the builder. Oh yes, and the silicone lubricant on the paper is doing a fair job, but only just fair, at protecting the plans. I think that I have to declare the results of the experiment disappointing. Plummet Quote Link to comment Share on other sites More sharing options...
Plummet Posted January 25, 2012 Author Share Posted January 25, 2012 Both sides made. In the instructions leaflet from DBS&S is to fix the undercarriage doubler plates and the engine bearers to the fuselage sides. No drama there, except that the bearers are on the plan as being 17 cm long, and the piece of 1/2" square beecy I got from the Model shop was only 30 cms long. I have cut the beech on the skew, so that the contact area is the same, as can be seen here. You may also be able to see the pencil lines I ruled on the plans, extending the line of the bearers so that iot is easy to place the side over the plan and to mark where the bearers should be stuck. Sorry if this is obvious to most of you, but someone did say that the art of a genius is seeing the bloody obvious for the first time. Plummet Edited By Plummet on 25/01/2012 13:18:10 Quote Link to comment Share on other sites More sharing options...
Plummet Posted January 28, 2012 Author Share Posted January 28, 2012 I have done a bit more work. The Barnstormer is a parasol wing model. The wing is suspended above the cockpit area by two duralumin pieces, that each look like upside down undercarriage legs. These are attached to two wooden blocks, which are fixed to the fuselage formers F3 and F4. Here is a photo of the rearmost of the two, F4. The former is ply, and on the plans the block is shown as spruce. Lacking any suitable spruce I have fabricated the blocks by laminating some plywood. Here you can see the block screwed and epoxyed to the former. F3 is similar, only with an added curved bit that will form the shape of the front of the cockpit area. I have indicated pilot holes that I have drilled for mounting the cabanes, and also where I have chamfered the side of the former. Here you can see the reason for the chamfer. This is the fuselage side with F4 test fitted behind it. The chamfer is to avoid the diagonal brace. The next job will be to glue these two formers to the sides to create the basic fuselage box structure. cold However before that, it is cold down in the cellar where I am working, so my next job is to make myself a fleece pullover to wear down there. My sewing machine calls - as does some more hot coffee.Plummet Quote Link to comment Share on other sites More sharing options...
Plummet Posted February 17, 2012 Author Share Posted February 17, 2012 The fleece pullover is a great success. My photography is not. I took a few photos of the work in progress, but they have turned out to be horribly out of focus. The camera was in close-up mode or something. Anyway, the fuselage is mainly complete - now I have started on the fin, tailplane, and wings. There are 24 wing ribs in total. In the set supplied by DBSport and Scale there were a couple where the laser cutting had not quite gone through, but they were easy to cut away. What is curious is that the wing ribs are a dozen each of two different thicknesses. It is not clear (to me) from the plan as to just which are the thicker ribs. The root ribs, yes, and the wing tip one. That makes 5 per wing. At least the cellar is a bit warmer than it was. Plummet Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted February 17, 2012 Share Posted February 17, 2012 Just adding a post so I can follow along Plummet..... Did you decide on a motor for her...? Quote Link to comment Share on other sites More sharing options...
Plummet Posted February 17, 2012 Author Share Posted February 17, 2012 Yes. I 'discovered' a nice Enya 41 FS was available for stealing from another model. (Thank you Flappit.) It seemed an economical option, but somehow she has managed to get me to part with money for something else - about which more - here - perhaps - if I can persuade her! Plummet Quote Link to comment Share on other sites More sharing options...
Plummet Posted February 21, 2012 Author Share Posted February 21, 2012 What sized servos? What layout? I am adding ailerons to the Barnstormer. I have cut out a section of the trailing edge near the wing tip behind the rear spar. Now I have to decide on one or two servos, bellcrank, snake or direct pushrod. I have neen looking at the Funcub and the servos that it uses, and their aileron servos are described as "Nano". The Fun-cub ailerons look larger than my Barnstormer's. But these servos are tiny. Will the "Nano" sized servos really be OK for my Barnstormer The wing is quite thick. At the leading edge of my ailerons they are almost 1" thick. It occurs to me that if I pivot them at the upper edge then a pushrod flush with the lower edge may suffice, and so I could end up without having to have a horn sticking out from the underside of the wing. That is, it would look a bit more like the traditional aileron-less Barnstormer. The ailerons will be about 3" deep and 9" long. The Barnstormer is not a zoomer, more a putterer. Assuming that I go for the twin servo approach, then what sort of size of servo would I need. Plummet Quote Link to comment Share on other sites More sharing options...
Big Bandit Posted February 21, 2012 Share Posted February 21, 2012 Hi Plummet, Regarding aileron servo's on some thing that size my preference would be for 16gram HS81 or similar. originally the aileron servo would be a standard one 42 grams or thereabouts using pushrods and two bellcranks and mounted in the centre section. So with two you would be saving 10 grams or something close. I would not be happy with two nano (9gram) on anything bigger than a parkflier. Cheers, Chris. Quote Link to comment Share on other sites More sharing options...
Ady Hayward Posted February 21, 2012 Share Posted February 21, 2012 Hi plummet, I would agree with Big Bandit and suggestfitting two servos in the wing. As for the size I would suggest some from the 16- 20g size upwards giving 2.5kg/cm torque would suffice for each aileron. I would guess the ailerons are not intended to be travelling full deflection at high speed so the smaller lighter type could suffice as opposed to standard servos. I've used similar sized ones on my planes with no ill effects. Adrian Quote Link to comment Share on other sites More sharing options...
Plummet Posted February 21, 2012 Author Share Posted February 21, 2012 Thanks folks. You are echoing my thoughts. So what is it about the Funcub that means that it can get away with teeny weeny servos? It is 53" span, and the ailerons are about half the wing span. It looks as if it is designed to be thrown about, at least the videos show it being agitated. Plummet Quote Link to comment Share on other sites More sharing options...
Big Bandit Posted February 21, 2012 Share Posted February 21, 2012 Hi Plummet, I would think that the Fun Cub has a far lighter wing loading than the Barnstormer, despite the fact that it can be trown about ( at least my Fun Cub is). The Barnstormer should feel more confident and solid. And is it worth the risk of a model for the sake of 16 grams. Just my two peneth. Cheers, Chris. Quote Link to comment Share on other sites More sharing options...
Eric Hartley Posted December 14, 2012 Share Posted December 14, 2012 Hi plummet Have just seen your post as I have sent for the DB Plan Pack for the 72 Barnstormer and was interested to see your templates made from 3mm MDF. Incidentally is there a scientific way of calculating the total wood and size required or just take a guestimate? Quote Link to comment Share on other sites More sharing options...
Former Member Posted March 2, 2013 Share Posted March 2, 2013 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
John Webb 2 Posted September 11, 2013 Share Posted September 11, 2013 Hi Plummet, I have just found your build site, do you have the building instructions for this model as a kit? John. Quote Link to comment Share on other sites More sharing options...
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