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Dronsfield's "Eagle" Surface Grinders
Although no manual was produced for the Eagle Grinders a
useful guide to grinding techniques can be found here

Eagle 534 Mk. 2

Manufactured from the late 1940s until the 1970s, the Eagle hand-operated surface grinder was built by Dronsfield Brothers Ltd. at their Atlas works in Oldham England. One of a number of UK-made hand-operated surface grinders, its main competitors were the very similar Capco, Superior and Herbert. Dronsfield also produced the Marlow miller, a low-cost machine once popular in schools and colleges. Design rights to the Eagle eventually passed to the Victa company, originally from Maidenhead, Berkshire, but later of Poole, Dorset. The Victa Company was involved in numerous projects involving small machine tools including the well known and beautifully-made Centec milling machine that began life in the early 1940s when the model was introduced as a development of the V.E.C. or Victa horizontal miller, a machine sometimes badged as a "Warwick". During the 1940s and early 1950s Victa also marketed lathes by other makers, including one by Grayson that they sold as the Warwick - as well as a quite different and rather advanced range of geared-head lathes marketed using the Hobson brand.
Built originally in two ranges, Standard and Heavy-duty, the former consisted of three sizes 1, 2 and 2A (identifiable by bolt-on head castings) and the latter, as the 3, 3A, 4 and 5, with a heavier knee, saddle and a head that, although it appeared to be in one piece with the column, was actually bolted on internally using two 3/4" Whit. hexagon set-screws; two sheet-metal covers, one at each side and held on with two screws, covered holes that gave access to the set screws.
By 1958 an improved Mk. 2 had been introduced (though this was made in one size only) with the early machines continuing in production for at least four (and possibly more) years alongside it. The final version to be offered was the 534, a type that can be distinguished from earlier models by its shorter base, taller column and distinctly bigger vertical-control handwheel. Last of all came the Type 543 Mk. 2, a model with a much more modern, angular appearance and its electrical controls arranged along the front face of the head.
All Standard versions mounted a 7" x 1/2" grinding wheel with the heavy-duty type fitted with one slightly larger at 8" x 5/8"; both sizes ran at 2700 r.p.m. and had a maximum clearance underneath of 9". Drive came from a motor mounted on a hinged plate in the base of the column, an excessively long and whip-prone Brammer (sectional) belt being used to transmit the drive to the spindle. The whip can be countered by using a PowerTwist belt which, because it lacks metal pins, gives a softer drive and can accept a mid-position belt tensioner consisting of two pulleys acting to spread the belt apart, with a left and right-hand threaded adjusting rod half way up the column (an easily contrived amateur modification). 
Fitted with a 15" x 6" table with 12" of stroke operated by a 7-inch diameter handwheel, the Model 1 is the most frequently encountered, but the Model 2 (table 18" x 6" with 15" of stroke) and 2A (21" x 6" with 18" of stroke) are not uncommon. However, the Heavy-duty sizes - the Model 3 (table 21" x 6" with an 18" stroke) and Model 3A (27" x 6" with 24" stroke) are seldom found, while the wider-table types, the Model 4 (20" x 8" with an 18" stroke) and Model 5 (27" x 8" with a 24" stroke) are almost unknown on the used market - and must have sold in tiny numbers. Longitudinal and cross-feed micrometer dials were graduated at intervals of 0.002" and the vertical at 0.0005" - though for metric markets these were changed to 0.0125 mm and 0.05 mm respectively. Rather fine sewed-edge expanding leather covers protected the ground slides with a telescopic guard over the vertical feed screw,
Intended for dry grinding, the ordinary machines had a single 7/16" T-slot but, if wet grinding was required, the makers offered the heavy-duty models, together with an additional No. 6 version (with a larger 21" x 10" table with an 18" stroke and 10.5" of cross travel) suitable equipped for this purpose. With a W suffix in their model-type designation, these grinders had a single-casting table with Neoprine oil and water resistant slideway covers - together with built-in waterways to return the coolant to a separate, floor-standing tank and pump unit.
Although early models with detachable heads are usually found with a dynamically-balanced, hardened and ground spindle running in bronze bearings, from some point in the late 1950s the latter were changed to ball races (though the catalogues also listed taper-roller bearings and, indeed, these have been found installed). Sized imperially, the ball races consisted of two opposed angular contact ball bearings behind the wheel with a single deep groove ball bearing at the drive pulley (rear) end. Interestingly, if the angular contact bearings are dismantled (they push apart) an owner reports that they can be revived by polishing the races lightly with diamond paste, fitting new balls and lubricating with ordinary lithium grease. The makers arranged for the angular contact bearings to be adjusted by fitting a selective distance piece between the inner races but it is possible to assemble them with a slight (just a few ounces) of preload with the rear bearing left to float axially on its outside diameter as original. Thus treated, the spindle is reported to run with commendable smoothness and precision.
Mk. 2 Eagle
Easily distinguished from the Mk. 1 by the use of plain flat sides to its floor stand (and usually a table with three T-slots), the Mk. 2 was announced in 1958; it retained the bolt-on head and, as mentioned previously, it did not superseded the earlier types but ran alongside them in the catalogues for a number of years. Eventually, before the introduction of the new range catalogued as the 534, the maker's listings were condensed to just a single Mk. 1 (with a 15" table with travels of 15" by 6"); the Mk. 2 (with an 18" table and travels of 15" and 6") and the Mk. 2A whose table, at 21" long" had 18" of travel - all types being limited to the same cross feed of 6".
Eagle 534
Last of the Eagle range (and possibly the only one to carry the name
Dronsfield's across stand's front face), the Mk. 1 534 was built as the No. 2 with an 18" x 6" table and travels of 15" and 6"; the No. 3 with a 21" x 6" table and travels of 18" by 6"; the No. 4 with a 24" x 8" table and travels of 21" by 8" and the No. 5 with a 27" x 10" table and travels of 24" by 8". As before, dry or wet versions could be supplied, the latter as the 3W with table travels of 15" and 5"; the 4W with travels of 18" and 6" and the 5W with a capacity of 21" and 7". The grinding wheel on all sizes and types was 8" x 5/8" with the hardened and ground spindle running in three ball races (as described previously).
Of completely revised appearance, the
534 Mk. 2 was an effort to bring the grinder's appearance up to date using much more angular lines. Just two Models were offered, the No. 3 with an 18" x 6" table with travels of 21" by 6" and the No. 4 with a 21" x 6" table and travels of 24" by 6". Fitted as standard with metric dials (Imperial was an option) the usual wet versions were offered - these being of identical capacity to the dry machines. One significant change was to the table-saddle ways where, instead of raised ways on the saddle, these were transferred to the table with the former having flats with inside V-edges.
In the late 1960s prices ranged from £260 for a Model 1 dry to £340 for a Model 6 wet. Extras included a dust extraction unit at £45, a low-voltage lighting set at £12, a wheel dresser with diamond at £3 : 10s : 0d and a push-button no-volt release switch at £2 : 15s : 0d.
For the small workshop an Eagle is an ideal machine; it takes up little room and is both cheap to operate and maintain - their being little to go wrong that cannot be fixed by any owner with reasonable mechanical skill..

The basic  Eagle Model 1 with table travels of 12" x 6" and bolt-on head

Eagle Standard Model No. 3 with one-piece column and head and a 21" x 6" table with 18" of longitudinal travel

Eagle saddle assembly as found on the Standard and Heavy-duty Models. By removing either of its stop buffer the table could be lifted off for cleaning 

Eagle saddle as used on the later Type 534 Mk. 1. Note the larger vertical-feed handwheel

Eagle Model 524 Mk. 2 One significant change was to the table-saddle ways where, instead of raised ways on the saddle, these were transferred to the table with the former having flats with inside V-edges.

Eagle Model 3W equipped for wet grinding

Eagle Model 4W complete with coolant tank and pump unit

Eagle Wet grinder with one-piece table with built-in coolant drains

Eagle No. 3 with a 21" x 6" working surface area table with an 18" stroke

Eagle Mk. 2A with bolt-on head and a three T-slot table

The penultimate Eagle, the 534 Mk. 1

Dronsfield's last Eagle Model the 534 Mk. 2--this is a Size 3 machine

Found abandoned in a field, this Victa-built, Eagle No. 3 has been beautifully restored - a task aided by its simple and robust construction

Note the adjustable gib strip on the knee, not on the table

Underside of the table

A little-used Eagle Mk. 2 with a three T-slot table as manufactured by Victa Engineering

Making a new spindle for the Eagle

Eagle 534 Mk. 2

Although no manual was produced for the Eagle Grinders a
useful guide to grinding techniques can be found here

Dronsfield's "Eagle" Surface Grinders
E-Mail Tony@lathes.co.uk 
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