Here Mathias glues and clamps the stringers to the stem as Jonathan hands him clamps. You can see how carefully he has cut the acute angles that will allow a good glue surface between stringer and stem, the product of careful measurement and work with the pull saw.
When all the stringers are glued into place along the stem, they must be shaped with rasps and sanding blocks until they meet in a fair curve. The top stringer in this picture joins the stem with the most difficulty because it must be twisted slightly. Some builders would put it in a long thin heavy duty poly bag and steam it to accomplish a radical twist. We just gave each of these a slight twist and then will sand down the sharpest outside edge. The top stringer above still needs more sanding so that the dacron skin will fit easily around the whole bow. You can see the sanding block made with red 80 girt sandpaper fixed to a block with 3M 77 adhesive. When the sandpaper wears out, we use a heat gun to soften the adhesive and put a new sheet on with a little more adhesive on the paper. The blocks allow you to fair several stringers together to create the overall shape of the bow.
In this photo Jamie is putting a curved edge on the stringers over which we will stretch the dacron skin. Just behind him you can see the pull saws, coping saws and rasps that now do much of the work of fitting the stringers.
Chris uses a rasp in this photo to round the edges of the stringers. Block planes would be useful in this work but we do not have a set. The fir is soft enough that the rasp can do the work quite easily.
Here you can see the top stringers now rounded as they comes to meet the stem.
No comments:
Post a Comment