Laminating
Laminating of timber is a most useful and rewarding method of construction. Strictly plywood is a laminated material but in this context I am referring to the making of components by gluing layers of wood together with their grain in the same direction in order to make something that would be impractical by other means.
From archery bows to large structural beams for big buildings laminating enables new and interesting forms to be achieved.
The simplest form of laminated component is the laminated beam. these can be very long and you can reckon on about a 20% to 30% increase in the strength of the timber as compared to a solid wood component. This is because any misalignments of the grain disappear at the glue lines and so a split is less likely to form. Usually the laminations are of reasonable thickness if the beam is large and are joined end to end using comb scarph joints. the laminations are coated with a suitable adhesive and clamped together either against a former or between two formers.
The same laminations can be bent to form curved beams and in this case some very interesting architectural forms can be achieved.
Smaller laminated objects made of hardwood laminations are very effective as well and I have made things as diverse as boats tillers and the curved top member of a classical harp using approximately 4 mm thick hardwood laminations. The Method used for very tightly curved items is to make a former and clamp the work to it as tightly as one can. You can make a laminated piece so long as the laminations will bend round the former. Something to watch out for is the fact that a bunch of laminations of a strong timber can be very tough to bend in themselves. This can be quite a problem especially when the glue has been applied and the whole thing is now sticky and also the laminations try to slip around on the layer of glue.
Using a water based glue also puts quite a lot of moisture into the wood so with thin laminations and tight curves you can get quite a bit of movement of the component as it dries. This movement will take the form of the curves becoming tighter and if your component has a curve between two straight pieces the angle between the straight bits will get less as the wood dries. If this is a problem and the work warrants it the use of wood epoxy glues ( which contain no moisture) will prevent the problem almost entirely.
Here is a use of laminating I use to good effect when making large molded edgings for tables with curved edges. I take a suitable piece of wood for the edging and cut it into suitable laminations on a good saw bench. Keeping the laminations in their original order.
To make sure the laminations stay in the order I cut them I mark a large “V” ( in black felt tip or something very bold ) on one side of the wood so that a piece of it remains on every lamination. When they are stacked together again it is then obvious if they are out of order. I then glue the
laminations round a suitable former and when they are finished the joins scarcely show at all depending on the timber. This often saves cutting the edgings in several sections, looks a lot better and requires much less work. This isn't so easy for round tables but I have made such edgings in two pieces on a couple of occasions. Three pieces may be more sensible though.
if you require to laminate a tapered object you can taper the idividual laminations on a shaped baseboard which you can pass through the planer with a lamination at a time on it. I have made some quite subtly shaped components this way.
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