The ability to cut out wing ribs that are both accurate and fairly quickly is important,you dont want to loose interest with your model because you are chained to the self healing cutting board for days ! no,there are easier solutions to ease the problem nicely,this is one tried and tested way that I have been using now for many years-
Firstly make two ply rib templates complete with the required amount of notches for the spars and leading edge,make this very accurate otherwise every rib will be wrong,so take care with them.
Next make another ply blank that is big enough to accomodate the rib,ie just an oblong piece of ply,this will be used to cut the blanks ready to make the ribs and its accuracy is just as important.
Now stack the two ribs together onto the ply blank and make two drill holes through the lot so that everything lines up,use a pillar drill for accuracy on this.
Next job is to cut out the required number of blanks per number of wing ribs required,if the number of ribs is great then you can make up into two batches.
Next place all of the balsa blanks between the two ply template ribs and either with two small clamps or place into the jaws of a wood vice or better still as we need to drill through the lot clamp to the baseboard of your pillar drill again,next drill two holes,if you cannot find a drill long enough then make one by flattening the end of a piece of piano wire and grind the end to a 'v' point,this will make an adequate drill for the job in hand.
Now get two pieces of threaded rod ( B & Q are a good source for this ) and push this through the whole lot and with washers and nuts bolt the lot up tightly but not crushed.
Now the exciting part at last,with a razor plane,coarse sanding block or surform whittle away until you get down to the template line,then finally sand off smooth and with a razor saw cut the various slots for spars etc,now unbolt the lot and you will be rewarded with a beautiful set of ribs clean as a whistle,what about tapered ribs I can hear you saying ? well no problems,just cut a root rib,plus a tip rib and clamp together in the same way sanding to meet both templates,you will get a slight bevel but this can be easily sanded away if you want.
You will never cut another individual wing rib once you have tried this,the ribs are so neat and tidy as well.
Firstly make two ply rib templates complete with the required amount of notches for the spars and leading edge,make this very accurate otherwise every rib will be wrong,so take care with them.
Next make another ply blank that is big enough to accomodate the rib,ie just an oblong piece of ply,this will be used to cut the blanks ready to make the ribs and its accuracy is just as important.
Now stack the two ribs together onto the ply blank and make two drill holes through the lot so that everything lines up,use a pillar drill for accuracy on this.
Next job is to cut out the required number of blanks per number of wing ribs required,if the number of ribs is great then you can make up into two batches.
Next place all of the balsa blanks between the two ply template ribs and either with two small clamps or place into the jaws of a wood vice or better still as we need to drill through the lot clamp to the baseboard of your pillar drill again,next drill two holes,if you cannot find a drill long enough then make one by flattening the end of a piece of piano wire and grind the end to a 'v' point,this will make an adequate drill for the job in hand.
Now get two pieces of threaded rod ( B & Q are a good source for this ) and push this through the whole lot and with washers and nuts bolt the lot up tightly but not crushed.
Now the exciting part at last,with a razor plane,coarse sanding block or surform whittle away until you get down to the template line,then finally sand off smooth and with a razor saw cut the various slots for spars etc,now unbolt the lot and you will be rewarded with a beautiful set of ribs clean as a whistle,what about tapered ribs I can hear you saying ? well no problems,just cut a root rib,plus a tip rib and clamp together in the same way sanding to meet both templates,you will get a slight bevel but this can be easily sanded away if you want.
You will never cut another individual wing rib once you have tried this,the ribs are so neat and tidy as well.
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