Friction, Lubrication and the Lubricants in Horology.

by William T. Lewis.

INTRODUCTION.

Many books have been written on the various escapements, describing their action, construction and proportion, and the laws governing the same; learned writers have contributed much valuable information on adjusting; excellent attachments for the various lathes have been invented; and factories have expended fortunes to produce machinery of wonderful construction to finish all the parts of a watch in the most approved manner; but all this scientific research, all this painstaking effort, all this care and labor, are rendered abortive by the maker or repairer of a time piece if he does not thoroughly understand and apply the physical laws which govern the science of lubrication.

Many a watch, or chronometer, most excellent in all other respects, has come to an untimely end by an almost criminal neglect on the part of its maker to provide against wear in its various parts by such construction as would retain the oil at the places needed.

How often the repairer--clean he his work as well as he may--replace he the broken or worn part to put the time piece in as good condition as new--finds that its rate changes, that is loses time before long, and, at the end of one year is badly out of repair, solely the result of lack of knowledge, or negligence, in properly lubricating, or on account of an oil having been used which was not suitable.

The object of this paper is to present in concise form the best of that which is furnished by the literature of the profession, together with that which has been written on friction and lubrication in general (so far as it may be applicable), by those not connected with this particular vocation; as well as the result of the practical experience of the manufacturers of time pieces in this country most of whom have furnished much useful data in answer to queries on the subject. The manufacturers of oils have also a.s.sisted by contributing valuable information.

The result of the author"s experience, observation and experiments will also be incorporated; and he will be grateful to any who may read this work, who will call attention, through the trade papers, to any errors of omission or commission that they may find therein.

CHAPTER I.

LUBRICANTS IN HOROLOGY--THEIR SOURCE AND METHOD OF REFINEMENT.

~1. As but little~ is to be found on the subject in the literature accessible to most of the craft, a few remarks concerning the source and general methods of refining the oils used in horology will, no doubt, be of interest.

A mechanic who would work intelligently should possess a thorough knowledge of the materials constantly used, and oil is used on every horological mechanism. In order that this paper may be of maximum benefit and interest, the author has spared no pains in procuring useful data.

~2. Porpoise Jaw Oil and Black Fish Melon Oil~ (64) have become widely known and justly celebrated in all parts of the world, as they were found to be better adapted for the purpose of lubricating fine and delicate machinery than any substance _previously_ used.

~3. Blackfish-Melon Oil~[1] "derives its name from the ma.s.s taken from the top of the head of the animal reaching from the spout hole to the end of the nose, and from the top of the head down to the upper jaw, from which it is extracted. When taken off in one piece this ma.s.s represents a half watermelon, weighing about twenty-five pounds ordinarily. When the knife is put into the center of this melon the oil runs out more freely than the water does from a very nice watermelon. Porpoise jaw oil and blackfish melon oil are worth from $5 to $15 per gallon, according to supply. They are not only used in horology, but by manufacturers of fine firearms, philosophical apparatus, and in government lighthouses for the clocks of revolving lights."

~4. The Blubber~, or fat, taken from the jaw of the porpoise or the head of the blackfish was formerly rendered in iron pots over a fire, but the modern method of extracting the oil by steam is said to be much superior. The oil is washed with water by thorough agitation, after which it is allowed to stand for several days, when it is drawn off and the last traces of water removed by distillation. The oil is then subjected to a very cold temperature and pressed through flannel cloths, by which process the "oleine" is separated from the "stearine," the resulting oil being more or less limpid as the former or latter const.i.tuent predominates.

~5. John Wing~, of New Bedford, Ma.s.s., son-in-law of, and successor to, the late Ezra Kelley, states in answer to inquiries, that their supply of oil comes from the porpoise and blackfish taken during the summer months on the coast of Africa, above the equator; and that they find that this oil contains less glutinous matter than that obtained in and about the St. Lawrence river, which fact he attributes to the difference in the food of the fish, which in turn affects the oil.

~6. D. C. Stull~, of Provincetown, Ma.s.s., in answer to inquiries on the subject, has kindly furnished the following information and series of views:

[Ill.u.s.tration: _Fig. 1.--Buying a Porpoise from a Fisherman._]

"The supply of porpoise-jaw oil and blackfish-melon oil comes mostly from Ma.s.sachusetts Bay, the trap and gill net fishermen bringing them into Provincetown, sometimes alive, as shown at Fig. 1. The capture of fifteen hundred blackfish, Fig. 2, by the people of Provincetown, Truro and Wellsfleet, was one of the most exciting scenes in the annals of coast fishery. The fish were attracted to these sh.o.r.es by the large quant.i.ty of squid and herring, on which they feed. It is estimated that the catch was worth $25,000, some of the fish weighing two tons each.

The relative size of a blackfish and a man is shown at Fig. 3. Seafaring men and whaling captains who catch the porpoise at sea, extract the oil from the head and jaw only, and bring it to the factories to be manufactured.

"Fig. 4 is a good view of a modern factory. The fat is cut from the head and jaw, (Fig. 5,) washed in fresh water and put into covered tin cans, then into iron retorts, (Fig. 6.) These retorts are then closed, screwed up tightly, and live steam turned on from the boiler. The fat is cooked by steam for five hours, with ten pounds pressure, at 230 F. By this means the crude oil is extracted from the fat."

~7. Sperm Oil~ is the best known of all the lubricants and is, for general purposes, one of the most excellent.

The large cavity in the head of the sperm whale contains oil and solid fat, from which the former is separated, without heating, by pressure and crystalization. As it is not at present used to any great extent in horology, a more lengthy description of the method of refining will be omitted. (65.)

~8. Bone Oil~ is made from the fat obtained by boiling the bones of animals. The finest quality is obtained from the leg bones of recently killed, healthy, young cattle, and the best method of treatment is given as follows[2]:

"Fill a bottle one third full of the oil to be purified. Then pour clarified benzine in small portions upon the oil, close the bottle and shake until the benzine has disappeared. By again adding benzine and shaking, a complete solution of the fat is finally effected. That this has actually taken place is recognized by the contents of the bottle not separating after long standing. The bottle is then exposed to a low temperature for several hours, a solid fat deposits on the bottom, and the lower the temperature the greater is the deposit. Alongside the bottle containing the oil, place another bottle with a funnel, the lower end of which is closed by a cotton stopper; after thoroughly shaking the bottle with oil, pour the contents into the funnel; the fluid portion runs into the bottle, while the solid portion is retained in the funnel by the cotton stopper. The clear solution of bone oil in benzine collected in the bottle is then brought into a small retort which is connected with a thoroughly cooled receiver. Place the retort in a tin vessel filled with water and apply heat. The benzine readily distills off, leaving the purified bone oil in the retort." (66.)

~9. Neat"s-foot Oil~ is largely used in the arts, being one of the best of lubricants. The best oil, viz.: that used for clocks etc., is extracted by placing the thoroughly cleaned feet of cattle in a covered vessel near the fire or in the sun. The oil thus obtained is clarified by standing before bottling. (67.)

It was the practice of many olden time watchmakers to allow a large bottle of neat"s-foot oil to stand in a position exposed to the direct rays of the sun in summer and to the extreme cold of the winter. Then after two or three years, on a very cold winter day, to pour off such oil as still remained fluid which was preserved for use.

~10. Olive Oil~ has been used as a lubricant since the early days of horology, the older writers giving many methods of treating it. It is obtained from the fruit of the _Olea Europea_, one of the jasmines, which grows throughout Southern Europe and Northern Africa and other tropical countries.

[Ill.u.s.tration: _Fig. 2.--A $25,000 Catch of Blackfish._]

For the preparation of the finest oils, known as "Virgin oil," only the pulp of olives picked by hand is used. The pulp is packed in strong linen and the oil is expressed by twisting the linen together. The pulp sometimes contains as high as 70 per cent of oil.

Its last traces of adhering acid are removed by rigorous and repeated shaking with one hundredth part of their weight of caustic soda lye.

After the mixture has stood for several days a large quant.i.ty of water is added and the oil floating on the top is poured off.

Though the oil is now free from acid, it still contains coloring matter and other substances which would prove injurious. It is then mixed with very strong alcohol, ten parts of the former to two of the latter, and thoroughly mixed by shaking. The bottle containing the mixture is then placed in the sun and the mixture shaken several times a day. In the course of two or three weeks the oil will have become white as water, when it is withdrawn from the alcohol, on the surface of which it floats. The purified oil is placed in small bottles, tightly corked, and kept in a dark, cool place. (68.)

[Ill.u.s.tration: _Fig. 3.--Relative Size of a Blackfish and Man._]

[Ill.u.s.tration: _Fig. 4.--D. C. Stull"s Watch Oil Factory, Provincetown, Ma.s.s._]

~11. Mineral Oils~ have of late years taken immense strides in the popular and merited estimation of consumers, for general lubricating purposes.

Their application in horology will be discussed in another part of this volume. They are obtained from the residuum of petroleum distillation, and vary so greatly in their properties that many of them are not applicable to delicate mechanism; but as the lighter varieties seem to fulfill all the necessary conditions, the writer will here consider their source and method of treatment.

~12. Petroleums~ are obtained from many different localities, being fluid, bituminous oils, all having the same general characteristics and origin.

They are all hydrocarbons, and contain little or no oxygen. As their origin is thoroughly discussed in many works on that subject, and as there is such a diversity of opinion regarding it, the reader is referred to such works.[3]

~13. Paraffine~, both liquid and solid, is obtained by the distillation of crude petroleum by means of superheated steam. When the heavier hydrocarbons begin to come over the receiver is changed and the butyraceous distillate is filtered through a long column of well dried animal charcoal. The first portion of the percolate is colorless or nearly so.

The distillate is made water white by some refiners by an acid treatment, followed by a water-and-alkali washing. On exposing this ma.s.s to a low temperature it becomes thick, somewhat like "cosmoline" but white. (59.) It is then shoveled into cotton bags of very strong material and subjected to powerful pressure by means of a hydraulic press. This operation divides the paraffine into two parts: the solid paraffine wax from which candles, etc., are made remaining in the bags, while that which is expressed is paraffine oil. If the operation is carefully performed the oil will be free from crystaline paraffine at a very low temperature.

[Ill.u.s.tration: _Fig. 5.--Extracting Oil from the Head of a Porpoise._]

~14. Neutral Oils~[4] "are refined paraffine oils varying in specific gravity from 0.8641 to 0.8333. For the purpose for which these oils are employed it is especially necessary that they be thoroughly deodorized.

They are largely used for the purpose of mixing with animal and vegetable oils. It is said that a mixture of 95 per cent of a good neutral oil of the right gravity, and 5 per cent of sperm oil, has been sold for pure sperm. Ordinary inspection as to the odor and general appearance would fail to detect the adulteration. Having been subjected to the usual process for the extraction of crystaline paraffine, they will stand a very low cold test, and having been pa.s.sed through bone black cylinders, they are free from odor and have but little color. They are usually exposed for a few days in open shallow tanks for the purpose of removing the flurescence of petroleum oils. Unmixed with heavier oils they are too light in body (especially the lighter varieties) to be employed as spindle or machinery oils, but when mixed with such oils in the proper proportions they form admirable lubricating compounds for general lubricating purposes when very high speed is not required."