email: tony@lathes.co.uk
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Fobco Drills
A dismantling guide can be ordered on-line here
For the correct motor and spare parts please
email or phone: 01298-871633

Fobco Continued here on Page 2 of 2

While few companies can boast of spending over 40 years making just two basic models of a drilling machine, but F.O'Brian of Swadlincote can - producing only the 4-speed "Star" (in several versions) and the heavier No. 2 Morse taper "7-Eight" (and very similar No. 3 Morse "10-Eight"). Now out of production, both types were of very high quality, beautifully finished (with chrome-plated ball handles) and ran with unusual smoothness and precision; as a consequence they continue to command (in good condition) a premium price and are well worth seeking out if you require a drill vastly superior to the usual cheap Far-East imports.
Mounted on a cast-iron base plate into which socketed a solid-steel, 55-mm diameter column, the drill was fitted with an 8.5-inch (215 mm) square table that could be rotated in either direction through 90. The head (also in cast iron) was locked to the column by a powerful, lever-operated clamp and arranged to allow some 6-inches of throad. The spindle travel was 3.75 inches (95 mm) with control by a single lever sliding in a simple, adjustable clamp and with the return spring housed in a graduated housing. Five different versions of the spindle end were manufactured and two quill types: fitted originally was a small-diameter (about 15 mm) spindle with an ordinary Jacobs No. JT6 taper (often found with a No. 34 Jacob chuck); this was replaced by two different spindles that required an internally modified quill: one used the same Jacobs taper as the original, the other was bored to take a No. 2 Morse taper socket and the nose threaded to take a collet-retaining nose cap (a photograph of the three types is at the bottom of the page and lathes.co.uk have stocks of these).
Another offering was a long extension to the spindle, this normally having a No. 1 Morse socket but also, occasionally, found with a No. 2 - in which case the Model Type was listed as the Fobco "5-Eight". A disadvantage of this type was that the amount of room taken up between spindle nose and table on the bench-top model - though it's perfectly acceptable on the floor-standing version with its long column. As the larger spindles made a considerable improvement to the drill's performance, Fobco offered, for a short time, a complete drop-in replacement quill, bearing and spindle assembly to upgrade older models - and one or two examples of this might still be available from lathes.co.uk.
A single diameter for its full length, the early quill was equipped, at its lowest point, with bolt-on bracket to hold the threaded depth-stop screw; this quill will only accept spindles that do not have an internal No. 2 Morse taper socket. The second quill, which was the same diameter as the first, had the depth-stop bracket formed as part of the casting - this change of design allowing the bottom section of the quill to be bored out to take the larger spindle with its No. 2 Morse taper socket.  Drills sold with the modified quill could also be supplied with a spindle having an ordinary Jacobs taper on the end; all the various types are illustrated below in the picture section.
Normally fitted with a 0.5 h.p. 1425 r.p.m. motor (with a neat built-in switch on the left-hand face of the head), 4 speeds were available: 475, 1020, 1990 and 4260 r.p.m. Unlike almost all competitors, proper cast-iron pulleys used for both motor and spindle - thus ensuring superior grip and extended life. As a point of interest the top bearing in the shaft assembly is an ordinary ball race, but the lower pair are a pair of angular-contact type. When the assembly is rebuilt some end loading is required on the bearings - and this can be done with a length of tubing, the setting being locked by a grub screw through the top collar (ensure that it bits into a new part of the shaft, not the original dimple). At first the bearings will be slightly tight and to correct this it's necessary to seat them properly by giving the end of the shaft a single smart tap with a 2 lb lump of brass. After this the shaft should spin freely and sweetly
According to an interview conducted by the writer with the Company's owner, Fobco began by machining parts (presumably under sub-contract) for the makers of "Progress" brand drilling machines (distributed through the Elliott Group) as well as a much lighter, cheaper model for use by amateurs that was retailed exclusively through the London mail-order department store Gamages. However, after visiting the London store and seeing the retail price, O'Brian realised that the profit made by Gamages was several times that achieved by himself and decided to enter the market on his own account - and so the first Fobco "Star" drill came about, designed by his son, Frederick Thomas.
Continued below:

Standard 4-speed 0.5-inch capacity (fixed chuck)  Fobco "Star".

Continued:
One interesting version of the Star was the "Universal", designed for light milling duties. This model came with a No. 2 Morse taper spindle equipped with a nose threaded 1.125" x 12 t.p.i., a worm-and-wheel driven fine down-feed gearbox and a compound, T-slotted table. Cutters were held in collets formed with a No. 2 Morse taper on their outer surface and pressed into the spindle by a screw-on nose cap - the system being identical to that used for Myford lathes. Each collet had a groove cut around its circumference near the end and could be "snapped" into the nose cap. The Myford collet set (actually made by Crawford) had a loading and unloading tool that eliminated accidental breakage of the collet end - this consisting of a tube with a Morse taper on the inside into which you pressed the collet to close it down. Once closed the nose piece could be slipped over the end of the collet and the whole withdrawn from the loading tube - relieved of pressure, the collet expanded and gripped the inside circumference of the nose cap. Morse taper collets are available from RC Machines in Luxemburg - though these lack the groove round the end and might be difficult to remove once installed.
It appears that a version of the "Universals" was also sold without the threaded nose for use as a precision co-ordinate drilling machine and these, because there is no method of providing a drawbar to secure the cutter, must not be used for milling - the sideways forces would cause the taper to loosen and the tool to drop out.
With a maximum throat of 10 inches and a spindle travel of 5 inches, the "7-Eight" was fitted as standard with a No. 2 Morse taper socket and was thus designed for the comfortable drilling of holes up to  7'8-inch diameter - that being the largest size drill made with a No. 2 Morse shank. The head used a 5-speed direct belt drive from a rear-mounted 0.75 h.p. 1425 r.p.m 3-phase motor that, in conjunction with an oil-bath reduction gearbox, gave 10 speeds of: 51, 98, 157, 222, 295, 460, 880, 1415, 2000 and 2650 r.p.m. The gearbox was entirely enclosed within the head and used ball-bearing supported shafts carrying gears made from heat-treated steel - a design at variance with some competitors who, for the sake of quiet running, employed rather weaker fibre gears. An oil-level sight-glass was fitted on the left-hand slide of the head. The quill was of substantial proportions and carried a spindle running in a matched pair of angular-contact bearings at the bottom (that absorbed both radial and angular thrust) with a deep-groove ball race at the top. On pillar models the 15-inch by 16-inch (381 mm x 406 mm) table could be swung over under the control of worm-and-wheel gearing and elevated by a rack and pinion. On bench models the head was elevated by a rack-and-pinion gear and the table formed from a heavy casting with three T-slots and a coolant trough around its periphery - this superior unit being available as the rise-and-fall table on the floor-standing pillar version. To simplify changes of speed both front and back sections of the belt guard could be hinged open (leaving the centre section bolted down) and the belt tension quickly slackened and tightened again through a patented (No. 758824) screw-thread-operated scissor mechanism. The spindle return spring tension could be adjusted by hand with its housing marked in the usual way with a scale to indicate the spindle travel. A useful option, though one seldom taken up, was an individually fused and switched built-in low-voltage lighting unit with the bulb neatly mounted  inside the underneath of the head.
A heavier version of the 7-eight was also offered, the rare "10-Eight" that carried a No. 3 Morse taper spindle, a 1.5 h.p. motor and the T-slotted table as standard. In all other respects the machine was identical in capacity and speed to the "7-Eight".
The background to O'Brien's was typical of many smaller engineering concerns of the time: the founder, Frederick O'Brien, was first involved in the ceramics trade before going into partnership before World War One with a Mr. Pascoe Tunnicliffe. As the war began the two men turned their attention to the manufacture of munitions but, in 1916, in what appears to have been a sudden split in the arrangement, Frederick bought a disused bakery in Swadlincote and started his own ironmongery and machinery business (still operating today as
B.Grice, Ironmongers). By the time the Second World War began, in 1939, Frederick (this time with the aid of three sons), was once more in a position to turn his hand to the making of munitions, amongst which were three orders, each for one million hand-grenades. As most were not, of course, used, they were scrapped, but numbers do survive and, being stamped FOB, are easily recognised. By the end of the war the business had a well-equipped workshop and began looking for other work. Initially, sub-contract machining was undertaken for Qualcast and this rapidly developed into a full-time commitment. However, sensing that reliance on just one source of income was a risky undertaking O'Brien decided to diversify and make two products much in demand to meet the post-war building boom: bench drills and concrete mixers--the latter designed by his brother, Garnet O'Brien..

The Fobco "Universal" (based on the "Star") with a threaded spindle nose to accept internal No. 2 Morse taper collets compressed by a nose cap with the same 1.125" x 12 t.p.i. Thread as used on a Myford Series 7 lathe. A worm-and-wheel driven fine down-feed gearbox was fitted and a well-made T-slotted compound table.

The rare "long-nose" Fobcp Star drill with its spindle extended to form a No. 1 Morse taper socket on the ordinary "Star" but a No. 2 Morse on the even less frequently found "5-Eight". As this arrangement took up so much room between spindle nose and table, it's best avoided on the bench-top version - though it's perfectly acceptable on the floor-standing model with its long column.

The No. 2 Morse Taper "Seven-Eight" with s speed-reduction gearbox built into the head. The handle by the motor was used for slackening and tensioning the belt. This example is fitted with the optional and very heavy T-slotted table that incorporated a coolant drain around its outer edge

To simplify changes of speed both front and back sections of the belt guard could be hinged open (leaving the centre section bolted down) and the belt tension slackened through a patented (No. 758824) screw-thread-operated scissor mechanism.

On pillar models the table could be swung over under the control of worm-and-wheel gearing and elevated by a rack and pinion.

Standard-table Fobco Seven Eight pillar model

A beautifully restored Fobco Star bench drill. This example has a No. 2 Morse taper quill with a 1.125" x 12 t.p.i. nose thread

First version of the Fobco Star spindle  - one diameter from end to end

Above, the later spindles. At the top is the one to take a direct-fitting Jacobs chuck on a JT6 taper, below is the type with an internal No. Morse taper.
With an external 1.125" z 12 t.p.i. (Myford) thread to take a nose cap that compressed collets formed with a No.2 Morse taper on their outside.
Both these spindles will only fir the late-type quill with the depth-stop housing formed as one piece with the quill instead (as on the early
Types) being bolted on. Pictures of the two quill types are shown below.
Examples of both spindles and quill are available from lathes.co.uk  Please email for details

Left: fitted with a 1.125" x 12 t.p.i. Thread as used on Myford Ml10, ML7 and Super 7 lathes and, right, the ordinary original spindle with a Jacobs taper in a JT6 size

Early type quill with the bolt-on depth-stop housing

Late-type quill with the depth-stop housing formed as part of the casting.
This design enable the bottom section to be bored out to take a No. 2 Morse taper socket

Badge from the F.O.'Brian Model 5T MaxiMixam concrete mixer


Fobco Page 2

email: tony@lathes.co.uk
Home   Machine Tool Archive   Machine-tools Sale & Wanted
Machine Tool Manuals   Catalogues   Belts   Books  Accessories

Fobco Drills
A dismantling guide can be ordered on-line here
For the correct motor and spare parts please
email or phone: 01298-871633