Your furniture should always be hand-planed and scraped, for, though the slight hollows and ridges left by the planing-machine may not be noticeable while the wood is in its natural state, as soon as the surface is finished and begins to have a lustre these inequalities become conspicuous. This applies to any small irregularities of the surface. You cannot get the surface too smooth. You will be surprised at first to see how noticeable slight defects in the surface become in the finished work.
Curved edges occur often in furniture. Many of these curves can be cut with a turning-saw or a keyhole-and compass-saw, but the easiest way (and the most accurate, until you have acquired considerable skill with the saw) is to have them cut at a mill by a jig-saw or band-saw at but slight expense. Have a piece of waste wood put on the under side to prevent the burr, or ragged edge, left by the sawing. These curves can be smoothed with the spoke-shave alone, or spoke-shave and file, or file alone, according to the conditions, as you will soon learn by experience, the final finishing of the surface being given with fine sandpaper.
Put the different parts of your article of furniture completely together once (without glue or nails) to see that everything fits right, that the joints close properly, and that the whole job is as it should be, before putting together permanently.
This often seems to the amateur a needless precaution (and it occasionally is), but, although it takes some time, it is the practice with skilled workmen and therefore a precaution which should not be neglected by the beginner. You will discover the importance of this when you carelessly assume that all the parts of a writing-desk, for instance, will come together properly, or that you can easily correct errors as you go along, only to find, when you have the work nearly put together that something is wrong. In the effort to mend the trouble you will be apt to loosen the parts already fastened, or will have to take the whole apart, which, when glue or nails are used, is particularly discouraging, and apt to damage the quality of the work.
Be particular to clamp the parts of your work together thoroughly when using glue and to allow time enough before removing the clamps (see Clamps and Gluing).
Care should be taken in putting your work together to get it "square," that is, to prove the accuracy of the right angles. In some cases this is of course essential to having the work come together at all. In others, the appearance will be much injured if the article tips to one side or is slanting or twisted. In all cases it is essential to the proper closing up of the joints. It will not do to assume, as the beginner often naturally does, that because the parts of the work seem to be accurately made that the whole, when put together, will, therefore, be square. It must be tested. You will be surprised to see how much "out of square" and how winding the result of your most careful work will sometimes be if you do not test it as you put the parts together. In addition to the obvious way of applying the square (see Square) to the angles, using the large steel square when you can: there are many cases in which measuring diagonals is a good test, altering the angles of the work until the two opposite diagonals are equal, when the work will, of course, be rectangular. This is a good way for large "case" work, using a stick, or fitting two adjustable sticks, after the manner described on page 167, between the angles, when the latter can be altered until the diagonals are equal.
At the same time that you are testing for squareness you must also look out for winding, by sighting across the front or back, using winding-sticks, if necessary.
When your work has a back fitted in, as in the case of a bookcase or cabinet, this will help you much in the final adjustment.
Do not attempt to put your case work together in an upright position, but upon horses horizontally, or flat upon its back or face.
It is well to use corner-blocks in the angles of your furniture, in places where they will not show (see Corner-blocks, in [Part V].).