
The long awaited propeller is a disappointment and the model deserves better,the propeller is far too thick at the hub outward of the blades because no helical pitch or undercamber has been added,as it stands the prop would struggle to even move the aircraft forward ! it is no good pretending that it is right because it falls far short of accuracy,however there is a solution but it will require some effort on the part of the builder,the idea is to get the blades thinner along the undersurface and to do this we will need to scrape in the undercamber taking into account the beautiful twist as any propeller has,think of this as a screw,which it is,the best example is a ships propeller,take a look and see what I mean or if you live close enough to an air museum that has a world war one aeroplane in the collection ( such as Old Warden) then you have your pattern in front of you.
First of all place a ordinary glass milk bottle into an old towel and tie up the end so the bottle is enclosed inside,now with abandon simply smash the bottle against a concrete surface,now carefully lay out the debris ( what is this man on about,I can hear you saying ! ) and amongst the broken pieces you will see some curved very sharp pieces of the glass,carefully watching your hands ( wear gloves for this) sort out the useful curved sections,next take you propeller and turn it over in a vice with pieces of wood clamped to the sides,carefully and patiently scrape the full length of the blade gradually removing the surplus wood,at the same time observe how the pitch starts to take on a gradual curve working from the root to the tip,you will be emulating exactly the practises of the old propeller manufacturers from days gone by,these were men of great skill and passion for their job,the used hundreds of station templates to achieve the exact shape of the blade,and once this was finished they had to carefully balance the prop in a knife edge jig,just as we do with our flying model propellers.
Once you are satisfied that the shape is correct,then start to use rough,medium and finally fine garnet grades of finishing paper,we will need to re-varnish the prop using some marine grade clear varnish,apply two coats with a soft brush rubbing down in between coats.
The decals are stick on affairs,I would have preferred proper waterslide transfers but these are not bad and look good when in place,once on apply some Johnsons Klear,but not varnish as this goes straight through the sticker and looks awful !
With a bit of extra care your prop will look a vast improvement from the lump supplied,almost forgot to mention that mine had wood that was of two similar a dark lamination,thus these do not show up as well as they should do,there is no answer to this except to carve a new propeller from scratch,this we will be dealing with in a future tutorial when time permits.
The propeller is another important step towards the completion of the model,how it will bolt onto the short propeller boss will remain to be seen ? probably some type of insert.
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