1/32 Scratch Build Royal Aircraft Factory BE 2a

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7 months 1 week ago #391 by Stevef
Evening All,

Many thanks to those who commented on the Short No 2 Biplane: your comments are very much appreciated.

This next project has come about almost by default. When I completed the de Haviland 1A I put it in a purpose made perspex display box, only to find that I had made a measurement error and the box is only just big enough to hold the model! I bought a second larger box for the de Haviland and now have a spare box. What to put into it? The box restricts the size of the subject: I had thought of an RE 5 or RE 7 but both of these are too large to fit. Other smaller subjects either do not interest me, are available as kits or are going to be released in the future, so they were all crossed off the list. Then the idea came to me to build a Royal Aircraft Factory BE 2a, (the predecessor of the better known BE 2c), as this was my first "free-lance" conversion (ie. I did not use an article but built it myself using the Airfix DH 4 as a donor kit for the wings, wheels, prop and struts), and it is very unlikely that a kit manufacturer is going to issue one at any time soon. This is the model I built in 1978:



When I made the above model I had originally wanted to build a BE 2c but detailed sources were limited and I could not find any drawings of the type. Therefore I built the BE 2a because I had a copy of Profile No 133:



Building a model of an aeroplane in 1/32 scale means that a great deal more information is needed. Fortunately DataFile No 163 provides excellent 1/48 scale drawings and many photographs:



There are also many photographs of replica machines at Point Cook in Australia and Montrose in Scotland, and there is a replica BE 2b in the RAF Museum at Hendon. Recently this fine volume has appeared on the type:



This book is a mine of information on the type and a go-to source for information: there is a review in Cher Ami vol. 10 no 1.

There was only one outstanding problem: I could not find enough information on the 70 hp Renault engine dimensions to be able to scratch build one, (there are no kits of this type available in this scale). In the meantime I continued with other True Scale projects until I had a breakthrough via RichieW of ww1aircraftmodels.com. He is scratch building a 1/32 BE 2c and has to make a 100 hp RAF 1A engine. He was discussing how to make the cylinders on that website when "Rookie" gave him the engine sprue of the WingnutWings RE 8 which had an RAF 4A engine. The RAF 4A engine was a 12 cylinder V which had been developed from the 8 cylinder RAF 1A. The latter was an upgraded version of the Renault 70 hp and as Richie only needed 8 cylinders for his model that left two spare cylinders which he kindly passed over to me. I now had a potential solution to my biggest problem - how to scratch the 70 hp Renault engine - because I could now calculate the critical dimensions and had sufficient information about specific details to make an attempt. If I can build the engine, I can build the remainder of the model.

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7 months 1 week ago #392 by Stevef
I intend to use as little aftermarket material as possible on this build, so I will only show it if I use any. Apart from the engine the other part that I was concerned about making was the 4 bladed propellor. I have made 2 bladed props in 1/32 scale, and 2 and 4 bladed props in the True Scale, but this would be my first 4 bladed prop in 1/32 so I started with this. I have a supply of hardwood strip, (I do not know what the wood is - I inherited it from my father many years ago), which I use to carve RFC and RNAS props. I cut two long strips and 4 shorter ones:



The long strips were glued to make a cross and the 4 shorter pieces then glued to each of the 4 arms with Evostick wood glue to give me the correct thickness of wood to carve. This was pressed for 24 hours in my state-of-the-art press (a pile of books):



The shape of the blades was drawn on to the surface of the cross and arrows drawn to indicate which way the blades needed to be filed:



The shape of the individual blades and boss were cut and filed first. This ensures that each blade is the correct shape and size when looked at head-on. The next step was to shape one of the blades: this was done with files only - it is too easy to slip when using a knife and the wood does not always cut smoothly, so an accident is possible and much time and effort can be wasted in a second if a mishap occurs. Filing may take longer but errors are much less likely. The arrows indicated the slope of the blade face - each one has to be identical to its neighbour and mistakes can be easily made here too. Final shaping and smoothing was done with glass paper:



The quantity of dust that filing and sanding one blade is shown here:



This is the finished propellor waiting to be varnished:





I will use a resin boss from Proper Plane, (an aftermarket product), as this will be in a very prominent position on the model and for once I am taking the quickest route!

I will post more on the engine later because at present it consists of a lump of laminated plastic waiting to be filed to shape.

Thanks for looking.

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7 months 3 days ago #394 by Stevef
Evening All,

I commented above that I intend to use a Proper Plane resin boss but did not provide a picture, so here is one:



Ideally I would like to make one of these, but I do not have the right materials and tools to do so, so I am opting for the [strk]easy[/strk] lazy route.

In between other activities I made the main and gravity fuel tanks from laminated card and painted them:



The filler caps may look large but that is partially an exaggeration caused by the lens, and partially because the originals were actually quite large.

I have shaped the engine block and made the timing cover for the front. All is from laminated card and strip with the circular plate and prop shaft support from rod: not difficult to make but fiddly and time consuming:



"Bolts" were added to the sides and rear of the engine block to represent the joint between the sump and head of the engine, the front was glued to the engine block and all painted in aluminium:



The arms sticking out of the sides are mounts which will rest on the fuselage frame later. The protrusion at the front is the magneto. I have also made a flywheel cut from a disc of card. The disc for the wheel was scribed using a pair of dividers and then the centre was shaped to a cross:





The arms are a little too wide but I cannot thin them much more or they will be so small that they will be too weak to handle.

Finally I am struggling with the cylinders. I have filed down the end of a piece of sprue to make the cylinder shape and then cut each length in turn:



The top of the cylinders was wider than the trunk because the inlet valve was positioned here. To make this wider part I cut and shaped some 60 x 180 thou strip:



The cylinders were bolted to the engine block via 4 long bolts. The bolts passed through cruciform clamps on the top of the cylinders so I shaped the latter from 40 thou card. First I cut a disc of card, then I marked a cross and finally I cut out the arms. On the right of the image is a cylinder with the head and arm in place:



There are still many more details to add before a cylinder is complete but I am having second thoughts about this method as I am not able to represent the cooling fins very well: scribing the plastic with the end of a scalpel is not as effective as I had hoped. In addition I will need to mount a small piece of aluminium strip to the top of one set of cylinders to represent the cowling and cover of the engine. This will need to abut the back plate of the engine which in turn must be made to exactly fit the fuselage frame.... In short I am of the opinion that the final engine assembly, including the bolts, push rods and valve springs, (which I intend to make from copper wire), and other assorted delicacies are best left until I have the fuselage frame and possibly lower wings completed. I can of course change my mind at any time and continue with the engine manufacture and assembly, but for the time being I will start to make ribs for the exposed parts of the wings, and the fuselage structure and interior details.

Thanks for looking.

Stevef.

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6 months 3 weeks ago #396 by Stevef
Evening All,

I have stopped working on the engine for the time being - I am experimenting with some ideas but have nothing worthwhile to show for it. I have also decided that until I am ready to fit the engine to the fuselage frame I do not want to assemble much more because the cylinder head bolts were used to hold part of the cowling in place and I will need to instal part of the cowling at the same time that I put the cylinders in place. If you are confused all will become clear later.

The fuselage will need to be robust to support the weight of the model so I have opted to use brass bar for the longerons and some of the frame. I soldered the sides first using the standard method of holding the parts with pins while solder was applied:



The forward part of the upper longeron was steel tube on the real aircraft so I soldered some brass rod to represent this. With two sides made it was straightforward to join them with some horizontal bracing:



A rudder post was soldered to the rear - again brass rod:



All of the joints have been cleaned with a file: the remaining parts of the frame will be CA'd into place later.

I have started to make the ribs for the wings. One lower wing and half of the upper wing will have the structure exposed so I will need approximately 30 ribs. The ribs closest to the centre had lightening holes, the remainder had slots. I tried 3 times to make the ribs with holes before I got it right... I have also cut one with slots. The image below shows the sequence of manufacture: top - a strip of 40 x 188 thou Evergreen strip, strip cut and shaped and holes drilled for spars, spar holes cut square, 2 versions of the rib with holes, bottom a rib with slots:



I will take some time to make the ribs and will work on some of the fuselage interior while I do so. I will be visiting family next week so progress will be even more glacial than usual and the next update may be some time away.

Thanks for looking.

Stevef.

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5 months 2 weeks ago #401 by Stevef
Evening All,

I have not posted anything for a while because I have been trying to make ribs for the exposed parts of the wings. I need 23 full sized ribs and 6 smaller ones for the tips. I had made the 23 full sized examples and was in the process of making the remaining 6 when i discovered that I had made a mistake - I had drilled and cut the holes for the spars in the wrong places for the larger ribs - all 23 of them....! Given that each rib takes about 45 minutes to make and I am not in the most motivated of states to make them, I will leave to your imaginations how I felt when I discovered my error. (It will save the mods having to delete this post if I do not write any more about that). At last I have finished the new ribs.... That was not as easy as I had expected either because I managed to spoil/ruin 10 more! In all 60 ribs made fro a total of 23 useable ones. I do not think that I will be attempting another large scale strip down model for some time. These are what the new ones look like - not all of them but you get the idea:




If anyone is wondering why I am making all of the ribs in one go, the reason is to try to maintain a consistent standard. If I were to make a few ribs, make something else and then start making ribs again I find that it is difficult to remember what has/has not been made/finished, and to keep a consistent standard of parts. I have also been experimenting making my own wicker seats but have not had much success there either so I may resort to some Barracuda resin examples instead.

I have been sent two printed engines from Beto: they are superb - I may use one of them but equally I may continue to try to scratch build one using the printed engines as a template. This is no disrespect to Beto's work - it is just that I would like to be able to scratch build as much of this model as possible. I am also experimenting with using some wood for interior parts - hopefully I can now focus on those next and start to make real progress rather than going around in circles and repeating errors...

Thanks for looking.

Stevef.

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