We all remember our grass roots and the very first models that we built,in many cases these would be kits of scale subjects produced by such companies as Keil Kraft,Veron,Skyleader,Comet,Keelbuild,Guillows etc etc.In many cases these kits would include inferior balsa sometimes the density of floorboards and would split under the balsa knife and flustratingly glued back together again !
Many of these designs were built on a keel with the formers glued onto them,then the slots for the stringers would be cut and an immensely strong structure would evolve,note how I say the stringer slots are cut after assembly and not cut out before as the kits incorrectly state ? the reason for this is the impossibility of knowing exactly where those slots actually appear,there is nothing worse than a stringer out of line which looks as if it had been on the Guinness ! with the advent of modern adhesives these models have been made much easier to build,no more fiddly waiting for balsa cement to dry as that critical part wanders out of line,a quick zap and the jobs done.
Before we even start our kit lets take a very critical look at how we can save valuable weight,most modern kits are now die cut,or more likely die-crushed if the cutting dies are worn out and have seen better days,in the later case it is best to consign these sheets to the trash bin and start again,to do this take the sheets before trashing to your local friendly print shop,ask them to print the sheets on sticky back paper,then all that you need to do is go home and place the sheets onto fresh lightweight balsa,by cutting the parts out the tacky film holds the wood together,then it is easily peeled off after cutting out.If the wood is ok and of reasonable weight ( a small set of digital scales is something that I need and suggest) then we can take a sanding block and remove a few thou of wood by vigorous sanding outside on a flat surface,by sanding on the reverse of the die cutting process the parts will just drop out from the sheets nice and cleanly,place these carefully into plastic food trays or something similar,nothing worse than loosing a vital part at this stage.Remember not to cut any slots we will do this much later with a warding file directly in situ on the model just prior to fitting the stringers,to avoid damage hold the former with a small wooden block with a slot cut into it,this stops the former flexing as you use the file.
That will do for now and I hope that these few words will give renewed interest in these small models that with care and attention can be made into little gems of a flying model,next time I will deal with other aspects of the build and also culminate with ways of even fitting micro radio gear into these models,yes it is now a practical proposition to do so,and the sight of a 15 to 18 inch span model up high in the sky and being flown from a cabbage patch is something else to really enjoy !
Many of these designs were built on a keel with the formers glued onto them,then the slots for the stringers would be cut and an immensely strong structure would evolve,note how I say the stringer slots are cut after assembly and not cut out before as the kits incorrectly state ? the reason for this is the impossibility of knowing exactly where those slots actually appear,there is nothing worse than a stringer out of line which looks as if it had been on the Guinness ! with the advent of modern adhesives these models have been made much easier to build,no more fiddly waiting for balsa cement to dry as that critical part wanders out of line,a quick zap and the jobs done.
Before we even start our kit lets take a very critical look at how we can save valuable weight,most modern kits are now die cut,or more likely die-crushed if the cutting dies are worn out and have seen better days,in the later case it is best to consign these sheets to the trash bin and start again,to do this take the sheets before trashing to your local friendly print shop,ask them to print the sheets on sticky back paper,then all that you need to do is go home and place the sheets onto fresh lightweight balsa,by cutting the parts out the tacky film holds the wood together,then it is easily peeled off after cutting out.If the wood is ok and of reasonable weight ( a small set of digital scales is something that I need and suggest) then we can take a sanding block and remove a few thou of wood by vigorous sanding outside on a flat surface,by sanding on the reverse of the die cutting process the parts will just drop out from the sheets nice and cleanly,place these carefully into plastic food trays or something similar,nothing worse than loosing a vital part at this stage.Remember not to cut any slots we will do this much later with a warding file directly in situ on the model just prior to fitting the stringers,to avoid damage hold the former with a small wooden block with a slot cut into it,this stops the former flexing as you use the file.
That will do for now and I hope that these few words will give renewed interest in these small models that with care and attention can be made into little gems of a flying model,next time I will deal with other aspects of the build and also culminate with ways of even fitting micro radio gear into these models,yes it is now a practical proposition to do so,and the sight of a 15 to 18 inch span model up high in the sky and being flown from a cabbage patch is something else to really enjoy !
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