The New Zealand Railways Magazine, Volume 1, Issue 5 (September 24, 1926)
If any good is to come from the “Safety First” campaign recently inaugurated by the Department, it behoves everyone to do something towards making it a success. There is no doubt that in every wood working machine shop many safety devices could be with advantage installed that would cost but little to make. In fact many of these could be rigged up by the machinists themselves in the course of their work. The use of such devices would be the means of preventing many accidents that are not only very painful to the injured at the time, but may permanently impair his efficiency.
In bringing before you these two small devices (see illustrations) I do so with the idea that they might result in an exchange of similar ideas through the medium of the Magazine, and thus be beneficial to all users of wood working machinery throughout the service.
The pressure bar (illustration 1) I have used extensively and I found it to be a very serviceable and useful tool, conducive to better work, as it holds the work firmly down to the table thus ensuring a first class job and also acting as a guard against having the hand pulled back into the knives.
Looking at the illustration 1, A. is the shaper top or table, B. the pressure bar, C.C. the right and left hand spindles, and D. the timber being worked. The pressure bar itself consists of a piece of sound and tough wood, such as red beech, about 4 in. wide and 1 in. thick, long enough to project over each spindle a matter of 4 in. The plan of the bar at E. will give you the idea of the shape; one end is slotted just big enough to take the spindle, the other end is slotted large enough to pass freely over the small collars. At this end a curved piece (as shown) is screwed across the grain for additional strength—this piece is slightly rounded on the bottom edge so as to allow the work to pass freely underneath.
When this bar is fastened between two of the collars on the spindle not in use, any pressure that is required may be had by raising or lowering the idle spindle. This appliance, which can be made with an expenditure of an hour's time, will make the work not only easier and better, but much safer; for if the stock should be drawn back into the knives the operator's hand would be thrown clear by the rounded end of the bar.
If both spindles are required at the same time, then the bar can be secured to the table and the necessary pressure applied with thumb screws.
Figure F. gives us a variation of the same idea. This, however, is not so useful, as it is a guard only. It is about the same size as the other, the hole being large enough to pass over the small collars. It will rest upon the collar that is holding the knives, the outside edge being large enough to cover the projecting part of the knife. It is then fastened to the table with a thumb screw, and holes can be bored (as shown) if the operator wishes to obtain a clearer view of the work.
In case of a cross grained piece of timber breaking when this guard is in use, the operator's chance of getting his hand caught in the knives is considerably lessened.
“Planer Protection” is really a misnomer, for, after all, it is not protection for the planer that is required, but protection for the operator. In examining illustration 2, you will see that A.A. is the planer top, B. the fence, C. the work being jointed, D. and E. the cover for parts of the knives not in use; F1 and F2 are wing nuts, the former holding the guard to the top of the table, and the latter holding the two parts of the guard together.
The cover for the knives is a piece of tough wood two feet long by seven-eights of an inch thick, and wide enough to cover most of the mouth of the planer with a piece of 3–16 in. page 9 three-ply, fastened at F1 so as to keep the guard above the cut of the knives. E. is a piece of stout three-ply fastened at F2 with a countersunk bolt with wing nut. This piece can be adjusted close to the stock, being jointed and parallel to the fence, thus completely covering the knives. The guard can be set to any width of stock, or swung out of the road altogether.
There is no doubt that the use of some such guard as this, together with care on the part of the machinist, would diminish the danger and help to prevent accidents.
I am sure that there are many such devices known to wood workers throughout the service, and that an exchange of ideas on these lines would aid in the adoption of some really good appliance leading to the reduction of accidents. If these were reduced by only one or two per cent, everyone concerned would be well repaid for any trouble taken.