For interest - How were fly-presses made ?

[Overland]

I've done some high production broaching way back when.
Just seems a very steep pitch, at about 2".
It doesn't really matter, but I find it interesting to wonder how it was done.
There's certainly a very obvious answer out there as there were many companies building these presses in the Industrial Midlands of the UK, back in the day.

 

[99Panhard]

I am pretty certain fly presses go back to at least the middle of the 18th century. In fact, I can think of a case from the Old Bailey c.1760 where a man was arrested for counterfeiting because he had a "coining press". When it went to trial it turned out he made escutcheon plates for the London gun trade and at least one of the prominent gunmakers testified on his behalf. I've wondered how the screws were made because they predate any known large screw-cutting lathe. One method that is possible is a wrapped thread. I have what I think is an early 19th century blacksmith's vice where the square thread is actually a separate piece of square stock wrapped around a bar and brazed. It would certainly be tricky to make but we often underestimate how good some of these mechanics were, especially if they were doing the same job over and over. They were every bit as intelligent as we are and in a society with a rigid class system there must have been some very bright workmen who, today, might go into highly paid professions that they were largely barred from in the past. A wrapped thread like this, carefully finished by a skilled craftsman could then be used as a mandrel to case a tin (or some alloy of tin) nut around in the body of the press. When it wore out, it would be a simple matter to melt it out and cast a new one.

 

[Asquith]

99Panhard’s post has got me thinking, or rather looking. I’ve found something about wrapped threads, and will post it later.

Regarding the introduction of fly presses, one source provides a date of c.1530, when Benvenuto Cellini was striking some medals using a screw press with a lever 13 ft long. He noticed that throwing the lever quickly produced better impressions. (A History of Technology and Invention, Ed. Maurice Daumas)

Cutting big screws:
Newspaper advert, 1738: 'ALL Sorts of Iron Screws, from two Inches and a Half, to five Inches Diameter and upwards, the Threads whereof are cut by an Engine with great Exactness, are Made and Sold, at very reasonable Prices, by ROBERT BOWMAN, Anchor-Smith, at Whitehaven in Cumberland.' (Newcastle Courant, 27 May 1738)

In 1754 R. R. Angerstein, a Swedish industrial spy, described the machining of large iron press screws by the Coalbrookdale Company (R R Angerstein's Illustrated Travel Diary 1753-1755: industry in England and Wales from a Swedish perspective, translated by Torsten & Peter Berg, The Science Museum, London 2001). Unfortunately his description and sketches aren’t very helpful. The cast or wrought iron blanks for the screws were first turned in a simple lathe powered by a waterwheel. The screwcutting was done in a wooden-framed machine driven by a hand crank. The machine had five pedestals, the first three supporting the hand crankshaft and the flywheel, with the third containing the bearing at the ‘chuck’ end. The blank was coupled to a master screw (the 'regulator') engaging with a nut fixed in pedestal No. 4. The 5th pedestal contained the cutting tool, evidently moved in and out by a leadscrew. The reason for using hand power rather than water power in screwcutting was to facilitate the required repeated reversals of motion.

In 1764 an advert for the sale of the Busy Cottage Ironworks in Newcastle included ''An Engine, moved by Water, for cutting Dyers and Pressers Screws, Slitting Mill Pillars, and for turning either large or small Work.' We can assume that the screws referred to are large and made of iron, being used for some process in the dyeing industry, for presses, and for rolling mills. (Newcastle Courant - Saturday 29 September 1764).

1765: Patent No. 829: '12th June 1765. 829. A grant unto George Pickering, of Busy Cottage, near the town and county of Newcastle-upon-Tyne, whitesmith, of his new invented method of making & compleating an iron screw for raising & lifting up timber, & other purposes therein mentioned; ….'. ('Titles of patents of invention, chronologically arranged covers period from Mar. 2, 1617 to Oct. 1, 1852' by Bennet Woodcroft, 1854).

 

[john.k]

The King of Pergammon was claimed the richest man in the world.....because he owned all the screw threads in creation..which he leased out to olive growers and winemakers. for their presses....without screws,the wine and olive presses had to make do with levers,and loading of rocks to provide the squeeze.

 

[swarfless]

Back in the 1840s Holtzapffel says most flypresses in England were made with a bronze nut on account of the cast iron of the day being too 'crumbly' to screwcut a large coarse thread ?? Both my Oz-made, late 1990s, have the threads cut directly in the casting. That's a 3 tonner & an 8 tonner made by A P Lever. Wouldn't be without either.

 

[john.k]

Possible both A P Lever and John Heine presses had cast steel frames...Heines are still going and will repair their old machines.

 

[Asquith]

From The Cabinet Cyclopaedia by Dionysius Lardner, 1833.

Methods of making large female-threaded nuts and sleeves in the olden days:-

‘The most ancient is probably that adopted by whitesmiths in general in the making of vices. The course is this:-
The screw A (fig 49) being finished, and a band of iron, forged to the proper size, and made very soft, is carefully wrapped round in the hollow of the screw, so as to form an exact counterpart to the worm; this coil, B, in being taken from the mandrel screw, is filed bright on the outside, and inserted within the welded iron tube C, which is likewise cleaned inside. The worm being found on trial by the screw, to be properly adjusted, the whole of the worm and interior of the box are plentifully covered with a mixture of pounded borax and water, and upon this is thrown a sufficient quantity of bits of brass wire to unite by their fusion the worm and box. The whole is then enveloped in a thick mass of fire-clay, and submitted to the fire; the workmen urging the heat with the bellows until the lump appears red-hot: the melting of the brass, and consequent soldering of the work, is indicated by a dense blue flame, which arises from the hearth, and which, after having continued for a few minutes, serves to assure the workman that the fusion is complete. The article is then withdrawn from the fire, and rolled until it is cool, upon the ground, in order that the molten brass may not fall in gluts on one side, and so impeded the progress of the screw. The clay is then knocked off, the screw worked into the box with oil, and the whole finished by filing or turning on the outside.'

‘ The next method, which is generally that resorted to for the production of boxes for fly-screws and others having several worms, consists in casting the work in brass upon the mandrel, which in this case becomes a model. To do this, it is merely necessary to place upon the iron screw a wooden or clay model of the size of the intended screw-box, and then mould the whole in a case of proper sand. The screw is then taken out, and the model removed; after which the screw, having been covered with a mixture of whiting and water, of the consistence of paint, to prevent the brass from adhering to the iron, is returned to the moulding case, and the brass poured in, so as to surround the screw at the place and to the extent occupied by the model. On becoming quite cool, the work is placed upon the anvil, and the brass lump hammered all round until sufficiently loosened by expansion to allow the screw to be withdrawn, which it will do readily when the latter is quite smooth and cut very true: any trifling irregularities are corrected by working the screw a few times through the box.’

The author noted that these methods could not be applied to very large nuts and bushes. Those, and female threads in general, were now produced by machining.

 

[99Panhard]

Last night I looked up "screw" in The Complete Dictionary of Arts & Schences (Temple Henry Croker, 1765). Unfortunately, while it mentions both wood and iron screws as well as square threads, there is nothing on how they were made. There are some very good illustrations (including a lathe) but the books are so big and awkward I can't get them in the scanner safely. I also have the Dictionary of Arts & Sciences (Gregory, 1806) to look at but that one doesn't have the great illustrations. The source Asquith quotes is probably the best...

My reading of Lardner regarding gunmaking leads me to think that he was often describing methods that were long established. He was not a mechanic himself so he must have relied on others to describe how things were done.

 

[swarfless]

Possible both A P Lever and John Heine presses had cast steel frames...Heines are still going and will repair their old machines.

Sorry John, no cast steel, just the nicest blemish-free 'high duty' iron (their term) in their presses, not a pore or hard spot to be seen. As to personnel, the J H fellows in Sydney were a pleasure to deal with, you could easily sense the pride in their products. Seems they've diversified beyond presses & sheet metal cutting/forming machinery these days. Survival I guess.

 

[Peter S]

Here is a close-up of a John Heine fly press screw thread and nut. It looks like a bronze nut?

Not my photos, they are taken from an auction.

Note the nice welded repair job on the back of the press. And the CNC retrofit?

Another Australian-made fly press seen in NZ was made by Selectron Industries. A fabricated steel job.

 

[Peter S]

I have an interesting book Early Engineering Reminiscences (1815-1840) of George Escol Sellers which gives first-hand accounts of various methods of manufacture during this period.

In one chapter he describes John White's Press-Screw Manufactory in Philadelphia. Sellers "watched with great interest his entire process at various times during my summer vacations of 1816 and 1817".

Writing of Southern tobacco growers and cotton planters "They must have screws for their presses, and these screws must be of John White's make; no others would be accepted if these could be obtained, not even imported screws".

Screws for cotton presses and paper mills had either a lantern head (a large globe head with holes through it) or a square body, slightly tapered (presumably like a fly press), the latter type being stronger.

These screws were made of cast iron and generally no larger than 6 inches in diameter. They were cast by Rush & Muhlenberg and then turned true by the same company.

John White then did the screw cutting on a primitive lathe using a “screw-guide” and a long-handled chasing tool, resting on the workman’s shoulder.

To get to the point – the heavy cast iron nuts for these cotton press and paper mill screws were screw-cut on a vertical boring machine. See attached text.



Screws for tobacco and other smaller presses (say 2 ¾ to 4 inches diameter) were of wrought iron and were screw cut in a similar way to the larger cast iron screws.

However, “The brass nuts on all the wrought iron screws were cast on them, the screws being heated and well coated with rosin and lamp black over an open charcoal fire”.

I have attached a few illustrations from this book.