For behold a New Era has come;
The future all the brighter.

—Thomas Carlyle.

Should machine operators grind their own tools? In the most up-to-date and best organised machine shops the answer is in the negative. The heyday of the tradesman who ground his own tools and supervised their forging has passed. Beyond a doubt the old system engendered a sense of pride in the skilled workman, who jealously guarded the tools he used.

But a progressive age like ours is no respecter of individual sentiment. In workshop practice to-day an organised collective system of tool grinding has taken the field. The reason for the change is that the machine tool revolution, which popularised the combination lathe, the automatics and the specialised single purpose machines, has all but blotted out the old line of demarcation that a few years ago so distinctly divided the skilled from the unskilled workers. There need be no regret regarding this change which has effected both man and machine. In speeding up and increasing production, it has assisted humanity. No longer is man the toiling beast of burden as of yore; to-day the machine toils, and the operators intelligently supervise, direct and control.

Tool Making.

It cannot be denied that there is a right tool for every job—that the supply of correctly ground tools can only be maintained by a definite system of tool grinding being insisted upon. The number and variety of tools required in a locomotive machine shop will appear very large where the individual system of tool grinding and designing is in vogue. This is mainly due to the fact that each machine operator has created a standard set of tools of his own. If all these tools were tested and the best tools sorted out and made the workshop standard, one would be amazed at the relatively few tools that are required in the make up of a standard set capable of meeting the majority of workshop requirements. This is what has actually been done in the world's most efficient machine shops. Moreover, to assure that the correct shapes will not be diverted from, specially designed tool grinders have been installed and are operated by a machinist who works from charts that give the correct rake, clearance and profile for every tool required.

The Floor Grinder.

In many shops where tool grinders have been installed in the tool room, floor grinders have also been set down in the machine shops. The setting down of the floor grinders has induced machine operators to touch up and ultimately grind their own tools. Possibly, a machine operator will claim that after he touches up a certain tool it cuts much better. This might possibly be true, but it does not in any way discredit the tool room system. It shows only that the best (the correctly ground tools) have not been selected in the make up of the shops standard tools.

The question now arises as to how to arrive at a good general standard. Theoretically, this can be taken from the makers' charts; but in the main, a workable standard must also be determined in the shops where the tools are to be used and, where the material to be machined is known, and the machining operations understood. Knowing these things and, with the gridance of tool grinding charts, an excellent standard set of tools should follow. Should tools, after correct grinding be interferred with on the floor grinder, the chances are that the good done by the tool-room grinding will be undone by that of the machine shop. This practice should be avoided and the floor grinders kept within their legitimate spheres of usefulness.

Tool Steel Economy.

Much of the high speed steel used in machine shops is, to some extent, unavoidably wasted. This is due to what is known as the short end, or to that portion of the tool shank that is held in the tool box or post. To minimise this wastage, tipped and circular tools are becoming quite common in large machine shops. The tipped tool came into prominence during the War owing to the shortage of tungsten, vanadium, molybdenum and other rare alloys. The term “tipped” is self explanatory; it being merely a piece of high speed steel slightly larger than the profile or plan of the top face of the tool, which varies in page 37 thickness according to the size of the carbon steel shank. The tips are brazed on to carbon steel shanks with a specially prepared compound, and, after brazing, will withstand the high temperature required when hardened. In some instances the tips are welded on, but efficient brazing is simplest and preferable.

The circular tool is another type of tool but rather limited in its scope. It is fitted in a sort of tool holder, and consists of a piece of round high speed steel drilled through the centre and ground out concave on the face that gives the cutting edge the required rake. The clearance is determined by a slight taper, and the cutting face or profile is slightly larger than the base.

These tools require less frequent grinding than the ordinary tool, as they can be turned round in the tool holder until the entire circumference (which is the cutting edge) has broken down. For roughing and facing, this type of tool is extensively used in Great Britain and abroad. So general has become their use in large machine shops that a specially designed grinder can be purchased for grinding the concave top face which provides the rake for the cutting edge.

It will be readily seen that a set of standard tools embraces every tool that can advantageously be employed. Their selection and ultimate success in operation is one of the acid tests of machine shop organisation and control.

(To be continued.)

A Glorious Trip.

The excursion run arranged by the Railway Department from Wellington to Wanganui over the week-end was well patronised, reports the “Wanganui Chronicle,” and the 420 excursionists expressed themselves as being pleased with the arrangements made for their comfort.

“We found the accommodation in Wanganui tip-top,” said a member of the party when conversing with a “Chronicle” man, “and although we had to see a great deal in a short space of time, arrangements were so made that the journey did not seem to be marked by any rush. As a rule haste is usually associated with excursions, and one returns home thoroughly disgrunted and tired. On this occasion, however, thanks to smooth organisation and good accommodation, every member seemed to be thoroughly satisfied.”

The visitor said the Railway Department attended to all the details of the trip. With regard to accommodation that was arranged to suit the travellers' pockets. The tariffs at the various hotels were listed and each person booking a passage had the option of choosing whichever suited.

Two ladies from Sydney stated that they were so greatly taken with the river scenery that they felt inclined to stay behind to do some sketching, a pleasure they had intended to reserve for a future trip.