Continued:
By the mid 1950s Portass had produced over twenty different models of lathe, together with a small selection of millers, shapers, drills, countershaft-drive systems, foot motors, vertical-milling slides and T-slotted cross slides. In reality, production of all but lathes appears to have been very limited - and even these were made in batches to order with, at any one time, only a small selection of the range available. As a typical example was the Model "C", a low-cost special sold only direct from the factory, the margins being insufficient to allow any dealer discount. The "C" was a very basic lathe, with a 3-inch centre height, listed in 1953 at £13 : 17s : 6d for the 10-inch between-centres model and £15 : 10s : 0d for the 17-inch and supplied without backgear or screwcutting and with the T-slotted saddle carrying just a single, swivelling tool slide. Even with its attractively low price few can have been sold and the model is rarely encountered second-hand. Another limited-production machine was a rather different backgeared and screwcutting lathe that broke with many Portass conventions; the 4-inch Heavy Duty appears to be even rarer, only one surviving example being known. Also seldom found, despite being promoted in (tiny) advertisements in Model |Engineer Magazine during 1954 is the 3" x 12.5" Model L. Backgeared but not screwcutting this is known to have had a rack-and-pinion hand-driven carriage with the saddle formed as a T-slotted boring table topped by a single swivelling tool slide. If you recognise this as a Portass model you own, the writer would be most interested in making contact.
Portass was also kept busy supplying machines for retailers to re-badge as their own and examples have been found marked: Altona, A.T.M., B.I.L., Bond's Maximus, "Eclipse" (for the Sheffield hand-tool makers James Neil & Sons) Excell, G.A. (George Adams), Gamages, Graves, James Grose Ltd. of London (the latter chiselling off the Portass name and substituting their own badge), Juniper, Randa, Temmah, Wakefield, Woolner and Zyto, All appear to have been based on established Portass models, nearly always a version of the "Junior" or the venerable "S Type", although in every case some small differences, usually down to cost-cutting, can be found.  However, it may be that some examples were not made by Portass, but copied - one Portass advertising sheet claiming: Beware of Imitations. Portass lathes are being systematically copied and marketed and purchases should be careful to ascertain that the maker's label is attached to the machine.
Most famous (though not the best selling) Portass was the popular and long-lived "Dreadnought". Unfortunately (and confusingly) the name was applied to a variety of models - but is most commonly found on a heavily built 35/8" x 20" gap bed, backgeared screwcutting machine fitted with tumble reverse and made for both bench and stand fitting. The typical Dreadnought model shown in the first picture below is mounted on the maker's "underdrive stand", and follows the sensible Portass principles of using, wherever possible, very long flat drive belts, in the case over 20 feet of them. However, one dreads to think of the transmission losses as the motor struggled to first spin a plain-bearing cross shaft (through the upper part of the left-hand leg) then a massive, 112 lb cast-iron flywheel and, finally, the strongly-built, bronze-bushed headstock spindle. In reality the machine performed extremely well, and an example used by the writer for a number of months ran with turbine-like smoothness - the flywheel proving capable of storing prodigious amounts of energy. The reasoning behind this design, and for not employing V-belts, was as follows: Short, tight V-belts rapidly promote ovality in the bearings, lack of resilience in the drive, undue wear and sudden load taking to the motor with a general lack of smoothness and finish to the work. Any old and experienced engineer will concur with this view. Unfortunately, the success of many tens of thousands of American Atlas and Craftsman lathes would appear to contradict this opinion.
Also shown on this page are very two very rare Dreadnought models with centre heights of 5 and 45/8-inches; it is known that only six examples of the version with a hinged "Perspex" cover on the front of the headstock and a screwcutting gearbox were made, and it must be assumed that the other model, with a more conventional appearance and screwcutting by changewheels, was also made in very limited numbers. One additional, infrequently encountered type was badged "Dreadnought Junior" - and seems to have been yet another variation on the ubiquitous "S Type" - though perhaps of a heavier build.
Most of the ordinary 35/8" x 20" Dreadnought models were supplied for both bench mounting and stand mounting first with flat belt drive - listed (for some unfathomable reason) by the makers as "Green List" machines (see illustration below) the only Portass known to have been offered with power cross feed - though the mechanism was Victorian in design with a power-shaft passing down the back of the bed. In the mid 1950s, as demand for the original, now rather old-fashioned looking Dreadnought waned (doubtless under competitive pressure from the success of the very much more up-to-date Myford ML7), Portass introduced the backgeared, screwcutting, 6-speed 35/8" x 17" gap bed D5 or "Dreadnought Five" (not to be confused with the quite different Mk. 5) almost a miniature version of the earlier machine with both headstock spindle and tailstock barrel of 1-inch diameter. The headstock was almost identical to that employed on the last design of "S Type" with a 9 t.p.i x 1.122" spindle thread and 3/8" bore but with tumble-reverse fitted as standard. The lathe was brought further up-to-date by the use of a long cross slide with 5 T-slots, V-belt drive and the complete guarding for the changewheels and backgear fitted as standard. A set of eleven changewheels was provided: 2 x 20t, 25t, 30t, 35t, 40t, 45t, 50t, 55t, 60t and 65 teeth. As is so often the case "new" did not mean "better" and the "PD5" (as it became known) was only a pale imitation of its heavier, more workman-like forebears.
Today, the most frequently encountered Portass (and so what must have been the best-selling model) is the Model S, a simple, 3" x 12.5" machine with a gap bed and (usually but not exclusively), backgear and screwcutting. Of late 1920s design, the lathe was re-modelled and brought back into production - "in response to many earnest requests from home and overseas" - in 1951, when it was available with centre heights of 3 and 33/8  inches and between-centres capacities of 121/2 and 18 inches.
At around the time when the D5 was nearing production, the firm suffered an almost terminal blow when a large number of patterns was stolen - so preventing them from supplying spares for the majority of older models. Stanley died in the early 1970s and the firm ceased trading with all the remaining stock of spares and patterns being destroyed.  Unfortunately the Portass family appear to no longer have any connection with Sheffield, and if any reader is able to supply additional information about the Portass Company, or the family,  the writer, a native of the city, would be interested to hear from you...
Tony Griffiths

The 2-inch centre-height lathe in the top left-hand corner of the picture was also marked "Eclipse"
Not every machine tool or accessory manufactured by Portass is shown here, but a representative selection. The rare and unusual long-bed lathe shown in the middle of the picture can be seen here.
The list below runs from left to right across the page; the first lathe, top left, being numbered No. 1

1. 21/8-inch Model A plain lathe (Model B had a compound slide rest)
   
2. 21/8-inch Model-de-lux plain lathe with compound slide and set-over tailstock
   
3. 3-inch Model S backgeared and screwcutting
   
4. 3-inch Model XL motorised plus a treadle stand
   
5. 3-inch Model XL treadle stand version
   
6. 3-inch Model XL bench lathe
   
7. Lathe carriers (dogs) in various sizes
   
8. S-Type motorised floor model
   
9. Fast-and-loose countershaft
   
10. Heavy Pattern fast-and-loose countershaft
    
11. Plain vertical milling slide
    
12. Mark V countershaft (non-adjustable)
    
13. 6-inch stroke shaping machine
    
14. 3 5/8-inch "Green List" Dreadnaught with cast-iron chip tray (shown on this page)
    
15. Bench countershaft
    
16. Changewheels
    
17. Boring table - T-slotted
    
18. Swivelling vertical milling slide
    
19. Fixed steady
    
20. Fast-and-loose countershaft with extra-large pulleys
    
21. 4-inch Heavy Duty lathe
    
22. Drilling machine attachment
    
23. Bench mount fast-and loose countershaft with striking gear
    
24. Travelling steady
    
25. 3-inch Model L lathe Please do make contact if you own one)
    
26. Foot motor (made in a variety of sizes)
    
27. 35/8-inch Green List Dreadnought floor model
    
28. Mk. 5 (Mk. V) lathe in 3-inch and 35/8-inch sizes
    
29. Angle plates in various sizes
    
30. 51/8-inch screwcutting and backgeared Dreadnought with 24-pitch screwcutting gearbox
    
31. 45/8-inch Dreadnought long-bed version
    
32. 3-inch Model S late type with braced bed
    
33. 3-inch model C plain lathe
    
34. Drill chuck 0--1/2"
    
35. 45/8-inch Dreadnought on twin pedestal stand
    
36. 6-inch stoke shaper floor model
    
37. 35/8-inch Green List Dreadnought floor model with motorised flywheel drive
    
38. 35/8-inch P.D.5 backgeared and screwcutting lathe (late-model Dreadnought)
    
39. Not shown--the rare round-bed Portass of the 1940s
    

Original model 35/8"-centre height Portass Dreadnought for bench mounting on a heavy cast-iron chip tray. This version was labelled by the makers as the  "Green List S.C. Bench Lathe" and could be had with power cross feed - though the mechanism was Victorian in design with a power-shaft passing down the back of the bed.

The largest-ever Portass: also called a Dreadnought this is a very rare model and was sold exclusively on an underdrive stand. It was the only Portass known to have been fitted with a screwcutting gearbox - though a version with a lower centre height and changewheels (below) was also offered. These lathes were made in both 45/8" and 51/8" centre heights (only six of the latter being manufactured) and fitted with No. 3 Morse taper tailstock barrels. The Perspex window in the hinge-open cover on the front of the headstock was surely a unique feature, enabling the fascinated owner to watch in jaw-dropping amazement as the "works went round".

An equally rare machine, this virtually unknown Dreadnought was listed by the makers as a 4-inch - but was actually slightly larger at 45/8". It was supplied on either a sheet-metal or cast-iron underdrive plinth (with a cast leg and chip tray) and fitted with screwcutting by changewheels. The motor was mounted inside the stand with a simple countershaft unit that gave a  final drive to the headstock by a flat belt running over 3-step pulleys. The belt passed over the front and back faces of the headstock  - the cover with the screwcutting chart being a cast-iron belt guard. The backgear assembly was mounted within the top part of the headstock casting - hence the unusual height of the casting above the spindle line - and was described in the advertising literature as being of the "top-geared" type. If the lathe was not fitted to the maker's stand the rear cover plate could be taken off to allow drive by a remote countershaft. The unusual backgear assembly was not the only eccentricity - because the gap in the bed was too long the front spindle bearing and spindle nose were extended outwards to give the cutting tool a better chance of reaching up to the chuck jaws. With a faceplate fitted the problem would have been even more serious - and only fresh air could have supported the front end of the saddle at the forward limit of its travel.
It is believed that a batch of these lathes, with their centre height increased to 51/8", was exported to Indonesia during 1963.

Bought new by the London Rubber Company (makers off "Durex" condoms) in February, 1942 this Dreadnought spent its early years turning moulds for (well, what do you think?) until it passed to a Nottingham engineering company and then, in 1954, to its present owner, Neale Chaplin. On its purchase evidence of a hard life came to light and Mr. Chaplin set about a comprehensive rebuild - a restoration that also involved some careful modifications to overcome a number of the limitations inherent in the original design.
Although modestly priced when new the Dreadnought was an honestly-built, accurate machine and, whilst the cosmetic finish may have left something to be desired, the basis was there for an impecunious (but skilled owner) to develop a much-improved lathe.
Notable on the machine below are a rugged but neatly-constructed hinged V-belt drive countershaft unit; drip-feed spindle-bearing oilers; a beautifully made T-slotted cross-slide large enough to be used as a boring table (note the closely-spaced gib-strip adjustment screws and three locks); a hugely extended cross-slide end bracket and feed screw (with a much bigger micrometer dial) to give increased travel and so make better use of a vertical milling slide; quick-set and 4-way rear toolposts (the latter essential for easy parting off on a small lathe); an adjustable carriage stop, coolant equipment, a Myford thread-dial indicator and, the crowning glory, an expensive Burnerd "Grip-tru" precision 3-jaw chuck.

Above and in the photographs below is a Dreadnought Lathe built in January, 1943 and identical to that illustrated in the advertisement towards the top of the page. Fitted to the "Underdrive" pedestal stand, the only modification to this "Green List Dreadnought" has been a change from flat to a V-belt drive from the motor to the first countershaft pulley - a sensible modification.
In 1976, thirty-three years after it was made (and sixteen years after the model went out of production), Portass made the new owner a special T-slotted cross slide and vertical milling slide for it - this attention to personal service was a mark of the Portass company, where all enquiries received a detailed reply from Mr. Portass himself. More pictures here.
Although a simple and rather old-fashioned lathe Dreadnought was accurate and honestly made and some experienced owners took advantage of this by making a series of simple, well-engineered modifications that overcame many limitations of the original design and produced a much more versatile and easily-used machine..
A decent length and hence good "wrap-around" is essential for successful flat-belt operation and when I first saw the remarkably well-preserved lathe pictured below the owner had arranged the flywheel-drive belt so that, instead of passing under the jockey pulley and increasing the belt contact, he had passed it over the top - and so reduced it. It says much for the machine's capabilities that he had, nevertheless, managed to make two model locomotives before the error was pointed out to him.
Originally, the lathe was supplied with heavy cast-iron covers over the changewheels and front section of the large drive pulley but, unfortunately, these have been lost. The headstock-bearing drip-feed oilers were not originally fitted, but every small lathe benefits from their installation - they are completely reliable (if rather fragile) and you can see exactly how the oil supply is functioning.
A version of the much lighter "Model S" was also available fitted to a stand of this configuration - but, usually being on a tight budget, the typical "S" buyer can seldom have been tempted by such luxury and consequently these versions are particularly rare.

Above: handwheel adjustment of the belt tension was provided by arranging for a jockey pulley to wrap the belt more tightly around the large drive pulley.

In its original form the flat belt drive from motor to countershaft would almost certainly have been a cause of trouble. The motor pulley was too small for effective grip and a change to a V belt set-up would have been a great improvement - as the first owner soon discovered.
As a point of interest, on many of the smaller American South Bend lathes the electric-motor shaft carried a V pulley, with a V belt driving onto large-diameter, narrow, flat pulley. This rather unusual arrangement (of a V belt on a flat pulley)  worked very well even if, to modern eyes at least, it appears illogical.