Manufactured by either Welling & Welling Ltd.of Stannary Street, London S.E.11 or  Womersley & Broadbent of Halifax, England -  companies of which nothing is known - the seldom-found Wellsaw mechanical hacksaw appear to have been built as just two models, the 4-inch and 6-inch (100 and 150 mm). From surviving illustrations it appears that the earlier models would have been made by Welling & Welling, their name being cast into the front face of the stand, while later versions had large, bolt-on badges instead and the edges of the stand used on the 4-inch given a slight bevel. The saw arm of the 4-inch also differed with smoother lines on those by Womersley & Broadbent. However, who made what and when will probably never be discovered for certain.
Selling during the 1960s into a crowded and competitive market, both Wellsaws were carried on a particularly heavy and rigid cast-iron base whose splayed sides ensured excellent stability. In addition, the designer had ensured that no part of the machine could project beyond the floor plan of the base, this feature allowing the machines to be installed, for example, with their back face right up against a wall.
Carried on prismatic ways - like many shaping machines - the sliding "saw bow" could be adjusted for a precise fit by gib-strip screws and, because the 4-inch model was intended for lighter work (especially on hollow small-section material but also solid sections), it's bow weight was adjustable along the arm. However, the 6-inch, intended for heavier work, had a just fixed weight. Supplied with the 4-inch  was a 12" x 1" (305 mm x 25 mm) blade and the 6-inch with a 14" x 1.25" (355 mm x 100 mm).
In order to regulate how quickly the saw descended, an adjustable plunger was fitted to the hydraulic cylinder and all rotating parts ran in either ball or needle-roller races packed with grease. For other moving parts either flip-top of oil nipples were fitted - the latter, if you have one of these saws, probably bunged up with grease…
Supplied fully motorised with a 1/3 h.p. (0.25 kW) motor on the 4-inch and a 1 h.p. (0.75 kW) on the 6-inch., drive was by twin, side-by-side V-belts - these running against a jockey pulley to drive the gear-type coolant pump, though this, together with its rear-mounted sheet-metal tank, flexible tubing, tap and fittings, was an extra-cost item. Cutting speeds, in strokes per minutes, were 125 on the 4-inch and 140 on the 6-inch. Sheet-metal covers guarded the belt runs while detachable covers fitted on the outside faces of base allowed easy access to the drive system. The electrical system was simple with an automatic cut-out fitted to stop the motor when a cut had finished and the usual No-Volt release, safety push-button starter, that prevented a restart after a power cut, mounted the front face of the base.
For both models a roller bar support was available, this having a good-sized triangular base 16 inches x 16 inches x 16 inches (406 x 406 x 406 mm) and screw adjustment through a range of 20 inches (508 mm) to 22.5 inches (571 mm) to set the height of the support roller - the normal setting being about 20.75 inches ( 527 mm) to line up with the seating of the vice. A stop-bar rod was fitted to both models, that on the 6-inch being 26 inches (660 mm) long with an adjustable collar that could be set to give from 0 to 17 inches (0 to 432 mm) adjustment of the piece to be cut off. Details of the rod fitted to the 4-inch are not known
Very compact at 36 inches (915 mm) long, 16 inches (407 mm) wide and 33 inches (838 mm) high, the 4-inch Wellsaw weighted 346 lbs (158 kg) - the corresponding figures for the 6-inch being 46 inches (1168 mm), 19 inches (483 mm), 33 inches (838 mm) and 664 lbs (293 kg)..