This article first appeared in Practical Engineering 1940 Vol1 No4. The contents within the article are accurate as of 1940. The article reviews various pieces of new equipment employed in Industry at the time.
Besco No.1 Hand-Operated Bar-Bending Machine
A robust and compact little machine for bending bars hot or cold with a minimum of effort is the "Besco" No. 1 hand lever bar-bending machine. This little machine, produced by the well-known London firm of F. J. Edward, Ltd., of Euston Road, N.W.I, is designed to bend flat, round, square, angle, tee or other sections, either hot or cold, into right, obtuse or acute angles quickly and accurately. An adjustable stop is provided for repetition bends, and its light weight makes it a very handy and portable machine. The base has four bolt holes so that it can be firmly bolted down to the bench. The blades of the holding vice are detachable, and the bending blade is adjustable for various thicknesses of metal. Many uses will be found for this handy little tool in the engineers' workshop or repair shop, and it is particularly suitable for locksmiths, tinsmiths and blacksmiths.
Low Voltage Lighting
The system of low-voltage lighting developed by the Igranic Electric Company, Ltd., of Bedford, in the form of their “Lo-Vo-Lite" low-voltage transformer-switch-fuse units, embodies the additional features of safety and economy to justify its recognition as an essential item of equipment in modern workshops and factories. The unit is contained in a cast-iron case and consists of a single phase, air-cooled, step down transformer from any normal line voltages down to 25 and 12 volts. Automatic protection against shock is afforded by the self-isolating construction effected by these parts being mounted on the lid so that before it is possible to touch a fuse, inspect the switch or carry out other maintenance operations, these active parts are completely detached from the supply.
Economy is effected by the use of low wattage lamps—in most cases 12 or 18 watts will give adequate lighting— and the sturdy filaments of such lamps result in much longer lamp life. This is particularly so on vibrating machinery.
There are two standard sizes, type AT, 48 watts, and type CT, 100 watts, continuous capacity, wound for A.C. supply voltages from 200 to 250 or 400 to 440 volts, and secondaries of 12 or 25 volts as desired. Other voltages or tapped secondaries, can, however, be specially furnished. A variety of lighting fittings are available, either for mounting on the transformer unit or on a separate connecting box base for wall, machine or bench mounting.
The Edgwick Horizontal Tapping Machine
With the introduction of the Factory Act, it became necessary to redesign the Edgwick horizontal tapping machine and the opportunity was used to make various improvements. The machines can be supplied with either motor or belt drive and for bench or pedestal mounting.
The whole of the drive mechanism is now totally enclosed in a headstock which is cast integral with the base carrying the work table. The internal mechanism has, moreover, been simplified so that only one friction disc is used to transmit the-drive to the forward and reverse wheels. The high-speed shafts are mounted in ball bearings and the special tap chuck is an integral part of the spindle which carries the drive wheels.
The machine operates on the well-known principle of a common driver mounted at right angles to, and between, two driven wheels supported on a shaft provided with a slight lateral floating motion. On presenting the tap to the work, the operator causes the forward drive wheel to make contact with the driving disc, thus feeding the tap into the work. Immediately the pressure is released and the operator commences to withdraw the work, the lateral play in the spindle allows the reverse wheel to engage the driving disc, thus reversing the tap. When the machine is supplied complete with electrical equipment, the switches and fuses are enclosed in the headstock.
A Filing, Sawing and Die-Making Machine
A machine that has achieved considerable popularity among those engaged in aircraft production and allied industries is the "New Wonder" filing, sawing, and die-making machine. It is handled by William Urquhart, 1,023 and 1,025, Garratt Lane, London, S.W.17.
This interesting little machine tool has been designed to cope with small and medium-sized work, not only to release heavier machines for larger jobs, but also to cut down the cost of using large machines for the general type of die work, which is usually of small dimensions.
There are two models, the Model D, which has a 10in. square surface table, and the Model E.L. which has a 12in. square table. The table tilts in two directions, 10 degrees each way, and provision is made for attaching the screw-feed attachment, which may be obtained as an extra. The overarm is designed so that it is equally suitable for filing or sawing. Filing may also be done by using the file rollers with brackets as a file support, but a file inserted in the chuck will also perform accurate work in the hands of a skilled operator.
The machine is driven by a 1/4 h.p. electric motor, having a speed of 1,725 r.p.m. The standard motor is for single-phase supplies at 200-220 volts, but non-standard motors can be supplied if required. The drive is by vee-belt, and the vee-pulleys give a choice of two speeds—380 and 500 strokes per minute. In the case of the Model D the stroke is lin. and the Model E.L. has a 1-3/8in. stroke.
The uses and interchangeability of the parts of this machine will be fairly obvious from the accompanying illustration. When using it for sawing, the saw is tightened in one end of the chuck and the other end is clamped to the side of the overarm. A spring in the overarm provides the proper tension for sawing out a die at any desired angle within a few thousandths of the marked line, leaving very little metal for filing.
A Crabtree Flush-Mounting Control Panel
One of the most recent additions to the range of automatic protective control gear offered by J. A. Crabtree & Co., Ltd., of Walsall, is the flush-mounting control panel.
The unit consists of a direct-on-line, automatic, triple-pole air break switch suitable for use on 400 volt supplies up to 4 amperes line current. A compensated thermal overload-release is fitted in each of the three phases and no-volt protection is inherent. The switch is mounted behind an attractively designed cast front plate measuring 5in. x 9in. The “start" and "stop" push-buttons and the observation window, designed to provide visual "on" and "off" indication, are neatly grouped in the centre.
The panel was originally designed for the built-in control of the Milford double-ended electric grinding machine distributed in this country by Messrs. B. Elliott & Co., Ltd., of London. It will, however, be of considerable interest to all who are concerned in the design of machine-tools, since the size and fixing centres of the front plate can be varied to conform to the requirements of most machines. It is pointed out, though, that wherever this particular plate can be employed, the need for new patterns is eliminated and early delivery is assured. In all cases the recess provided to receive the control must not be less than 6-1/2in. high by 4in. wide by 5-1/2in. deep.
A Dry Accumulator for Handlamps
In workshops and factories where night shifts are in operation, a new product by Graham Farish, Ltd., of Bromley, Kent, will be of particular interest. It is a dry, unspillable accumulator for torches, cycle and hand lamps, constructed with pasted lead plates, the negative of which also forms the outer container, whilst the positive is hollow and carries a cap for the admission of acid, distilled water, etc., and to permit gassing whilst on charge. The cell is supplied in a charged condition. The recommended recharging rate is 1/4 amp. for 12 hours, but this may be increased to one-third amp. for eight hours occasionally if speed of recharging is important. It has a rating of 2.2 volts and will run a 2.5 x .06 bulb one hour daily for 14 days, or 2.5 x .2 bulb for 20 minutes daily for 14 days.The insulating label tube is made of celluloid and may be readily removed for cleaning any acid spray, etc., from the cell. Each cell is 2-1/2in. high, 1-1/4in. in diameter, and weighs 4 ozs. The retail price is 1s. 6d. each.