Fig. 17
HAND BLOCKING
With Iron Heated by Electricity
The irons are made with various kinds of faces, some are perfectly flat, others with convex sweeps or curves, these are called “grecian” irons, and are intended to be used in recessed curves of crown or brim, which curves are known as “grecians,” but the skilful operative can adapt the curved sides of a flat-faced box iron to most of the concave places, so that except for extreme undulations, no recourse to the curved faced iron is necessary. There are many modifications of these general rules and methods, and it may be necessary in certain cases, such as the ironing of braids stiffened with media other than gelatine or water soluble materials, to employ other methods, but they are generally peculiar to the plait used and of a purely ephemeral nature. In some factories box irons are used, heated by patent fuel, others are warmed by gas and electricity, but the general convenience of the fire-heated pad causes the old fashioned iron to retain an almost universal supremacy. In work it is just as convenient as any other, and in cost it must of necessity be lower, for every factory must have fire for steam production and general warmth, and the coke burning furnaces in use in the smaller factories are usually constructed to achieve these two objects, and at the same time heat the blocker’s pads. In the larger establishments steam for heating and working is generally raised in separate adequately large boilers, with a specially constructed and economical furnace for pad heating. This is made with a shallow bed, a broad iron lip, on which pads can be changed, and a guillotine-like construction in front, with a “blower” which can be made to rise or fall, as occasion may demand for the regulation of the draught.
CHAPTER XII
BLOCKING BY MACHINE
The blocking of hats by machinery is a process much more recent in operation than hand work, and although its origin is more or less inside the possibility of a living man’s memory, so confused are the data connected with it that little or no reliability can be placed on the greater number of the traditions. One thing alone stands out clearly as a definite indication of first use, and that is the certain seniority of the pressing of Leghorn hats. It is almost self-evident that neither machinery or blocks to stand machine pressures would be made for the manufacture of unlikely or transient materials and shapes, and while the fashion of “Granny” bonnets, etc., was constant for nearly half a century, the details of their shapes offered too many difficulties to the would-be maker of a machine to press them, to induce any great inventive effort on his part. It needed something simple in outline, and something that could be done in large and recurring quantities, to give to the inventor the necessary impetus to produce a machine to impart to the hats their final finish. And 100 years ago there was nothing in the straw market, used either for hats or bonnets, that fulfilled the above conditions except the Leghorn hat. The making of this has been described in a former chapter. The early methods, either by wood mallet or slickenstone did not adequately fill the requirements; hand ironing was nearly as tedious and was rather dangerous, as the Tuscan straw of the Leghorns was so easily scorched, and as the demand increased the desire for a more expeditious, safe and uniform method of pressing grew with it. The earliest information, given with some reserve, is that an iron pan or dish was made, moulded to the shape of the hat, and that this was fixed over a metal cauldron in which water was kept at the boil, or was warmed direct by charcoal fires. These heated the pan sufficiently for the purpose; in fact, to-day, with all the improvements, and they are legion, steam heating in this manner to blocking machines is still general. The hat was damped and laid properly in the pan to its shape, and was pressed on the inside by a convenient tool of hard wood or stone, either of which was sufficient to squeeze the wet-softened straw into the crevices attendant on the edge of the crown and the corner made by the junction of the crown and the brim, and to impart the necessary shape to all sections of the hat. The next move towards the present models, was to have the pan as above, with a wooden, or sometimes iron, block which would, when the hat was laid in position, fit into it in such a manner as to convey an equal impingement on all parts. This was adjusted by means of an over working screw, by which some large pressures could be given. But these simple methods had great disadvantages; it was impossible to entirely synchronize the pressure on every hat, and it was extremely lengthy and tedious. A Mr. Samuel Howard, of Luton, invented a press on similar lines, but the action was horizontal instead of vertical, this served a very good purpose for a period until MM. Desbordes,[2] of Paris, introduced their hydraulic press. This consisted of a steam heated chamber in which was placed the metal “pan” or “dish,” it being the “female” mould of the required shape. The pressure was obtained by an overhead chamber to which an india-rubber bag was fastened. This chamber was very strong and heavy, and was, as it were, one end of a balance, working on trunnions, at the other end of which were two large metal balls as counterpoise.
To bring into operation, the chamber was pulled down so that the centre of the india-rubber bag, which was made with a teat, came into the crown opening of the pan; the chamber was securely fastened by means of screw lugs to the portion holding the pan, and a hydraulic press was put into action which filled the rubber bag with a sufficient pressure of water to distribute the power all over the hat in the pan; a gauge showed the pressure obtained and consequently an equal amount could be given to every hat. The results, therefore, were all alike, and as the press could be locked and unlocked in a fraction of the time required by the screw process, the work was greatly accelerated. Many improvements have been made in blocking machines since then (about 1860), but all the later models embody the important feature of the hydraulic pressure through the rubber bag. The next important step in the evolution of mechanical blocking was that introduced by Mr. Henry Keston, of Luton, adapted from a model made by a Mr. Beresford, of Stockport, Cheshire. This improvement consisted of erecting round steel uprights on the bed of the steam heated chamber, allowing the bag chamber, attached to which were slides fitting the uprights, to rise and fall vertically. The counterpoise was effected by a chain, attached to the top of the bag chamber, passing over a wheel supported by a bracket at the back of the machine and loaded with sufficient weights to adjust the balance. A hand or foot lever pressure was sufficient to raise or depress the bag chamber, and water connection to it was obtained by means of a corded re-inforced india-rubber swan neck. When the chamber had descended to its proper position it was locked by means of a stout steel three-armed part like the hub of a wheel, with three spokes radiating from it at equal distances. The hub was pivoted on the centre of the top of the bag chamber, and a short lateral movement of this part brought all three spokes under very strong hook-like lugs, and locked the bag chamber securely to the pan chamber.
Fig. 18
MACHINE BLOCKING
By Press of Beresford-Keston Type
Water pressure above the supply pressure was effected by means of a hand worked hydraulic pump, and the force was reckoned by a pressure gauge. This method was so much simpler and easier to work, and also was so much more rapid, that it quickly superseded its predecessor; and now, after forty years’ experience, is still the favourite model, although the machines of to-day contain many improvements not to be found in the original. By all these descending bag chamber models the blocking of the hat is identical. The only difference made is in the amount of pressure, some straws taking more than others without injury. The hat having been properly “roughed out” or “sweated,” that is shaped to its exact size without pressure by hand or machine, and still holding a little steam moisture, is placed accurately in the pan, the outside of the hat to the metal; inside the hat is distributed as evenly as may be a thick felt dummy (to prevent the straw from cutting the bag). If the edge of the crown is very sharp, such as one finds in a man’s boater, a ring of vulcanized rubber or similar material with angles corresponding to the crown edge is placed in position inside the crown before the felt dummy is introduced. The bag chamber is then brought down, securely locked, and the water pressure applied. Different materials require different periods of time to properly set, but while one is setting the operator “roughs out” another hat, so that when the mechanical process on the one is complete, its successor is ready for the operation.