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Cross Halving Joint Take a piece of softwood about 300 mm long and 50x25 and plane it to size. Square a knife line all the way round about 10mm from one end. Place the stuff against the bench hook and carefully saw it right through on the outside of the line. If you are not satisfied with the result try again. Take a firm stance behind the saw and point your index finger along the blade. If you find it hard to find the line with the saw take a fine sliver out on the waste side of the line with a sharp chisel to rest and guide the saw in. ** diagram of this and stance ** you will probably find your cut is constantly leaning in one direction or the other. Always try and correct your bias by tending to tip the saw the other way. This should correct the problem after a while. When it is corrected on the tennon saw it probably will be better on the others too. When you have got it right, as you look at it from the end, you should be able to see the cut line all the way round. **photo if poss** If you have any wood left set it out in two equal pieces and mark the waste. You can now make a cross halving joint. The pieces will need to be over 120mm long. ** setting out pic ** Set out the position of the housing in the centre of both halves in pencil. Set the marking guage to half the thickness of the stuff and mark the bottom of the housing working from the face side in both cases. To make a stopped line with a marking guage , make a pinprick with the guage at the place you want to stop. Now when you get to the hole the point of the guage will fall into it and should stop. Mark the waste with with a pencilled scribble, face side for one half and back for the other. Now separate the pieces. Place the second piece on top of the setting out lines on the first and tick both sides as close as you can to it with a sharp knife or a chisel. ** pic how to hold chisel for marking ** Now do the reverse to the other piece remembering to keep the face sides facing the same way. Now, using the trysquare extend the ticks across the wood and down to the guage line. Cut down to the guage line with the tennon saw remembering to saw the waste side of the line. There is no easy way of stopping just on the line. Just careful sawing, keeping the saw as level as possible. Take the first piece and place it in the vice with the guage line a little above the jaws. Take your widest chisel and make an upwards sloping cut across the housing just a bit down from the top. Continue taking thin slices (experience will dictate the thickness very quickly) until you are about 1mm from the guageline. Turn the wood round and repeat from the other side. Usually one direction will cut noticeably more easily than the other. Choose the easier direction and pare the bottom of the housing flat. To make the last cut start with the chisel in the guage line. Pare nearly right across then turn the wood round once more and take the last cut from the guage line once more. If the sawcut is not quite deep enough at this stage make it deeper by drawing the chisel across it in the same way as for setting out. Repeat for the other half of the joint. Now if you try the halves together they should ideally be a bit tighter than a good fit. This allows for a fine shaving from each edge for cleaning up before assembly. PAGE UNDER CONSTRUCTION Please send any quieries about this subject to me.
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