Founded in 1898 and based originally in Bienne, Switzerland, Hauser was eventually absorbed into the Societe Genevoise (SIP) group and today still form part of that now international and greatly expanded company. Today that organisation - now listed as resident in China - makes a variety high quality conventional and CNC controlled machine tools.
Although Hauser always placed a strong emphasis on their jig boring and jig grinding models, they were also famous for the specialised equipment and tooling made for watch, clock and mechanical instrumentation industries. Hundreds of different machines were manufactured including miniature, high-precision specialist milling machines; optical checking equipment; profile projectors; measuring instruments; many types of automatic and semi-automatic pivot-polishing machines; hardness testers; rotary tables; workshop measuring microscopes, machines for forming and regrinding tungsten carbide and ceramic wheels; automatic recesses milling machines (for the production of watch plates) and universal facing and boring heads, etc. A number of automatic, continuous-production machine tools were also offered, all designed to deal exclusively with tiny parts. Examples of the latter included transfer and multi-spindle profile milling machines; transfer units for machining small components in metal strips; milling and drilling machines with three horizontal work spindles; drilling and tapping machines with multiple horizontal spindles; milling, drilling and boring machines to produce watchcases; 3-spindle vertical millers and multi-spindle drilling, tapping and milling machines. Many of these special Hauser models were as one-offs, in very limited numbers - or even built to a customer's design in order to solve a difficult production problem. As such, though attractive to look at, superbly made and eminently collectable, they are often difficult to adapt to general or home-workshop use.
Simple designs of horizontal and vertical bench milling machines were produced in a bewildering variety of sizes and types - though again, most were really intended for production rather than one-off work - and with most featuring an unsupported cutter protruding from a lathe-like headstock assembly that limited their application to lighter rates of metal removal. On horizontal machines, the main body was usually of the type machined to accept a very heavy right-angle adaptor that allowed the head to be mounted vertically - though this required the setting up of a complicated drive system. However, as these machines were intended only for the relatively delicate work, very little power was needed and the drive was always by a round leather or fabric rope. Vertical millers were often based around a cast-iron base plate and main column formed as one piece, with a table moved by levers or screw feeds - or even a combination of both. Spindle heads were similar - and often interchangeable between horizontal and vertical models - with feed by lever against front and back (or up and down) stops with very fine-pitch, hardened screws and with cutters held by direct-fitting, draw-in collets. On vertical types, in order to provide as wide a range of movement and work capacity as possible, two slides were sometimes used: the head, for example, moving on an intermediate plate that its self could be adjusted for position by clamps against ways formed on the inner face of the main column.
A common fitting was a simple 100 to 150 mm diameter, lever-turned rotary table (again with screw stops) capable of mounting a variety of fittings including watch-lathe type faceplates with delicate clamps, angle brackets, dividing attachments and vices.
Jig borers should always be installed in a temperature-controlled room - often recommended to be at 21° - but as a precaution, to aid the stabilty and accuracy Hauser incorporated, on some models, a number of heating elements in the head assembly.
An important note: to avoid damage it is vital that the drive variator used in the single column Hauser machines uses the correct lubricant - Monsanto Santotrac 50. See this page for more details
As the reason for a jig borer's existence is its the ability to position a workpiece with great precision, makers invested many years' work into producing high-quality, ultra-precise mechanical and mechanical optical measuring systems. Prior to the 1920s (and as used in earlier locating machines developed in Switzerland around 1910) the Swiss SIP Company had led the way by employing very accurate leadscrews with scales calibrated down to 0.0002" (0.005 mm) on the smallest models and 0.0005" (0.015 m) on the largest. However, only the Moore Jig Borer Company in the USA could produce, on a commercial basis, screws that were pitch perfect over the whole of their (maximum 20-inch) length and required no compensating correction mechanism. Hence, although of a very high standard, even the SIP screws required some method of automatically modifying their micrometer dial readings. The solution was to check, with great precision, how far turning the screw actually moved the table - and to do this it was necessary to measure the travel very accurately, in small increments. The obvious candidate for a reference standard was, naturally enough, one of SIP's own standard scales - a very high precision steel ruler of such accuracy that other length-measuring instruments could be calibrated from it (SIP were the leading suppliers of these to Government, engineering, scientific, and metrological institutes worldwide). The feed-screw was turned and the tester recorded the simultaneous readings from micrometer dial and standard scale - the latter being read through a microscope attached to the vertical spindle. The next step was to prepare a "curve of errors" that was reproduced, in an enlarged form, on a strip of hardened steel fixed permanently alongside the table (and other moving elements, if required). As a slide moved, a small lever followed the strip's profile and transferred its (tiny) movements, via a rod held in brackets, to another lever at the other end. Connected to the last lever was the vernier scale, positioned next to the rim of the feed-screw micrometer dial and free to move relative to it. Thus, for any position a corrected setting was automatically obtained - though great care in taking the vernier reading was, of course, essential. This ingenious (but simply engineered) system is believed to have been first employed by SIP in their jig borers during the 1920s and ensured that the accuracy of a complete machine was greater than that of its precision feed-screws.
Following the introduction of the first SIP jig borer in 1919 (and their steady development during the 1920s) the Company decided that a standard scale should be built into the body of the machine and its graduations observed directly through an optical system with the results displayed on an illuminated screen. The first such model - a new Hydroptic type with a particularly smooth hydraulic table drive - was announced during 1934 and proved an enormous success with the standard scale method, combined with external rulers, micrometer drums and vernier scales, now able to provided toolrooms with the most accurate way yet of determining a position.
Hauser Screw-feed (non-optical) Jig Borers
Although Hauser made (when they were in direct competition with the much larger SIP Company) at least two twin-column jig borers, the No. 4 and No. 5, they were far better known for their smaller, single-column types the Series Nos. 2 and 3. These could be supplied with table-position readings readings taken direct from the feed screws using conventional micrometer-dials and vernier scales or fitted as "optical models" - the standard scales used probably being sourced from SIP, then the world's leading maker of such items. In this respect the Hauser's optical types were comparable with the Models 1-H and 2P from SIP..