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Garvin were an American firm, based in Spring and Varick Streets in the heart of the shipping district of New York City. The company offered a very wide range of products amongst which were millers in plain, horizontal, vertical, manufacturing, duplex and hand-operated types; smaller types of planers and profilers; "screw machines" (capstan lathes), a variety of spiral-gear and worm-milling attachments, spring-coiling machines, rotary tables, index centres of many kinds, tool and cutter grinders, die slotting machines, dividing heads, countershafts (including an ingenious slow-speed spiral-geared model), support bracketing, single and gang drill presses, headstocks, compound slide rests, capstan tooling - and a range of screwcutting and plain-turning lathes. The manufacture of Universal Milling Machines was a Garvin speciality for many years and the firm produced a wide range of standard and built-to-order designs. The No. 2 and larger sizes were fitted with a patented "Direct, Constant and Positive" feed where the slower rates of feed to the table were driven from the end of the milling spindle, and the faster feeds taken from the belt-drive countershaft; instantaneous changes to the feed rate being made by simply moving levers three levers. The gears in the table-drive box were hardened and run in an oil bath - the makers claiming that tests had shown as much 30 per cent of the motor power was consumed in driving the feed on heavy work whereas, with the Garvin system, this loss was largely overcome leaving more power for the cutter to remove metal - more details are given at the bottom of the page. On the Nos. 1 and 2 machines, the table power feed drive cones were made interchangeable - which tripled the feed rate and doubled the number of feeds available to a total of 24 feeds. The table feed screws were increased in size during 1905, adding greatly to their torsional strength and durability. The knees of all models were made as stiff as possible, being closed on their top and sides - and so did not need sliding cover plates to protect the telescoping vertical-feed screws and the multi-thread, worm-and-gear knee elevating mechanism. The extra stiff knee also made a better support for any arbor support braces it might have been required to carry. These improvements were then carried over to the cheaper range of plain millers also sold by the company..
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