Re: Spar building - cutting 45 degree corners in solid mast
The pictures in your blog are nice and very helpful to understand what you are up to. Great Work.
You are probably all done by now but I will comment on how I would think about removing the corners of the square laminated timber.
Rather than make a saw cut the long way parallel to the centerline of the spar, I would:
(0) make many saw cuts perpendicular to the center axis of the spar so the big lump of undesired material can be easily broken out of the way and then very easily plane/shave the small amount to finish just past the bottom of the saw kerfs that are your indicator of the final dimension. Making close cuts across the grain always leaves weak pieces that can easily be broken out and the nature of the grain on a cross cut is such that when splitting out small pieces the runout/splitting does not travel into the good finished portion.
(1) mark the spar with the desired finished dimension.
(2) make many Many MANY saw cuts perpendicular to the centerline that barely touch the marks of the final desired dimension.
(3a) If you have made many saw cut close together the bits in between the cuts can be knocked and pried/popped off and then simply plane/shave until the saw kerfs disappear.
(3b) The many cross cuts can be done by eye with a handsaw carefully watching and coming close to the two marks of the final dimension, but on a big job a jig is very helpful.
The jig could be made to help one use either a handsaw or a powers/skilsaw and for 200' of cutting, a power saw seems the right thing.
So, A cradle made to lay on the point to the spar that is being flattened/shaved off that will slid along the length, can carry a skill saw and the saw can make cuts to the depth desired. . . . and then slide the cradle a fraction and cut, slid, cut , slide , cut, slide, cut and eventually ou have little bits that knock out and a small planing job ( and LOTS OF SAWDUST : )
(4) This all assumes that what you are sliding the jig along represents the finished shape/taper. If the finished dimension is not a constant distance from the corner of the timber (tapered) then hand sawing to the final dimension lines still works. One can still get power assist by power sawing just short of the final dimension lines and then just finish each of the (200ft x 24 cuts/ft=4800cuts) cut by eye with hand saw . . . : )
Last edited by George Ray; 07-17-2017 at 06:54 AM.
This is the first lesson ye should learn: There is so much good in the worst of us, and so much bad in the best of us, it doesn't behoove any of us to speak evil of the rest of us.
E. Cayce