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Pocket Watch Case & Gold-filled Case Information "Click" to Login or Register 
posted
Relative novice that I am, I have a three-fold question concerning pocket watch cases/markings, a subject on which I have found information to be very hit & miss Frown and in somewhat limited supply:

(1) What are the best sources of general information on pocket watch cases and case markings? I believe that Roy Ehrhardt has a book on cases, but I have not had the opportunity to review it, thought I have several of his other publications. Is that book, or another in particular, a valuable research tool?

(2) Secondly, concerning the composition of gold-filled cases. I understand the process of two layers of solid gold welded & pressed around a sheet of base metal. Did the ratio of gold vary a great deal from case to case, company to company, etc.? Shugart refers to a process that used a sheet of base metal 3/4" thick between two sheets of solid gold 1/2" thick, or a content of 4/7 solid gold. I have read other sources that refer to slightly less solid gold, but still more than 1/2 solid gold content. These ratios seem quite high to me...is there more to the story?


How Gold Filled Pocket Watch Cases Were Made.
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The following text is taken from the 1897 Sears, Roebuck and Co. Catalogue.

As gold filled cases have become so popular in the last thirty years, and there is so little known by the general public of the relative proportions to the different materials that enter into their construction and the methods employed in making them, we feel it would be interesting to our customers and their friends to know more about such an important industry. With every line that we handle and list in our catalogue, we make ourselves thoroughly familiar as to the manner in which the goods are made, and the quality and proportion of each kind of material which enters into their construction. It is very necessary for us to do this in order to protect the interests of our customers, for their interests are our own. We employ men in each department who are thoroughly familiar with the construction of the goods they handle, know where to look for weak and strong points, and are thoroughly competent to judge and to protect the interests of both our customers and ourselves from being imposed upon by fraudulent concerns whose only object is to make up cheap, showy goods and market them to the unsuspecting public in competition with goods of real merit, which, if bought right, can even be owned for the same or even less than the shoddy goods. We can say without fear of contradiction that the average merchant does not employ competent people and even himself is not a practical man. Let us repeat that we leave nothing undone to thoroughly understand and know the merits of everything we sell.

There are at the present time eleven watch case factories in the United States, with a daily average of about 4,500 filled cases, or about 1,498,500 per year. Most of the watch case factories in operation at the present time are reputable makers who have been established a great many years, and have proven by the experience of over a quarter of a century that gold filled cases, when properly made, are not only theoretically, but practically, a success, and have given their owners entire satisfaction. We might say that is has been our good fortune and pleasure to have had the privilege of examining a great many gold filled cases which have been in constant use from 20 to 30 years, and, without exception, we found all of these which were made by reputable concerns to be in good condition and to all appearances to be equal to a solid gold case. (Of course, the joints were somewhat loose from wear, which is a natural consequence with any watch case.) Even thought the first gold filled cases were satisfactory as to wear and appearance, improve machinery and years of experience have made it possible to turn out cases at a very low price, which for style and appearance are far superior to a solid gold case and for wear are all that could be wished for. The following article, together with the accompanying illustrations, will give the reader a good general idea of how gold filled cases are made.

The first operation is to prepare a sheet of material which is composed of two sheets of gold with a plate of hard composition metal between. Instead of rolling all three plates out to the required thickness before soldering them together, which would be a very difficult operation and attended with unsatisfactory results, such as uneven thickness of the plates, not being soldered well together, etc. the material is made ready, by taking one piece of gold about 4 inches long and 2 inches wide, and another of the same length but thinner for the inside of the case, as there is no wear on the inside. Now, a hard piece of composition metal of the same width and length is placed between the two pieces of gold, and after placing a few bits of hard gold solder between the plates the three are put into a furnace and kept at a very high heat by a charcoal fire and a hot air blast. The solder soon melts, and all three of the original pieces of metal are in one solid piece.

This piece is passed between adjustable hard steel rollers, which are brought closer together by a set screw each time the plate has been passed through until it is reduced to a thin sheet less than 1-16 of an inch in thickness. A plate after having passed through several times. By this method all three of the original sheets are reduced proportionally equal so that neither all the gold nor the composition metal will be thicker in one place than another.

The next operation is to cut the plate into strips of such width as to accommodate the different parts of the case, which are to be stamped out by large rotary presses. The back, front and cap of the cases are stamped out in a circular plate, and the piece of the strip. Cuts are about one-third size.

By a single operation these round plates are forced into a steel die in a large rotary press which turns up the edges all round so as to give it a bowl shaped appearance. In another operation the edges are turned down, which is called the snap.

The next step is to place the piece thus shaped into a sectional hard steel concave die. On the inside is operated with very heavy pressure a small hard steel polished roller. Which forces the metal into the die in all parts, which shapes the piece to conform to the style of case which is being made. If the case is to have corrugated edges, or Star vermicelli work, or heavy engraving, it is formed in this die. This operation also shapes the inside edges of the piece so as to form the snap.

The piece this shaped is put on the head of a lathe and the inside edge is turned out a little with a sharp tool to make it snap and fit perfectly on the center of the case. After this is done a rotary cutter propelled at high speed is run across the edge to cut the seat for the joint (hinge). Two pieces of gold joint wire about 3/8 of an inch in length (joint wire is made in sticks about 4 inches in length with a small hole running the entire length, and is cut into pieces of the required length with a saw), is placed in the seat cut by the tool and bound into place with fine wire. Some bits of fine hard gold solder are then laid over the crevice and the pieces are held in a gas jet which is stimulated by an air blast. The solder is melted and secures the joints, after which the binding wire is taken off. A piece of solid gold is soldered on in the same way on the edge of the back of case to form the thumb piece.

The center of the case is made by taking a strip of stock (prepared in the same way as described in the first part of this article) about ¾ of an inch wide and 7 inches long, which is bent in a circle and the ends soldered so as to form a band or ring a little over two inches in diameter. This piece is places in a sectional die, which is held securely in a very heavy frame. A small hard polished roller is rolled on the inside of the ring with very heavy pressure until the metal comes into contact with every part of the die. The inside of the die is made in the exact shape of the outside of center of case so that when the metal has been well pressed in, it is shaped complete. The rough edges on the inside are now turned out (on the lathe) to the standard size to fit the movement.

The seats for the joints are milled out and joints soldered on as described above, except that one piece of joint wire instead of two are put on. The pendant is made by forcing a small piece of stock into a die. A small concave seat is cut in the center to receive it, and it is bound in place and soldered with gold solder.

The pendant bow (usually called the ring) is made of solid gold. The bezel (crystal ring) is made in much the same way as the center. All the joints (hinges) are now filed and broached so as to fit perfectly, the case springs are secured in their places and the different parts of the case are fitted together.

The next operation is to engrave the case, which is done by hand with a small tool about five inches in length. Engraving is very fine work and requires years of practice as well as a natural ability to master the art. After the engraving is done, the case is polished inside and out on cotton buff wheels from one to five inches in diameter, which run at the rate of about 3,000 revolutions a minute and are saturated with alcohol and red rouge (very fine powdered oxide of iron). The case is then washed carefully, put in a soft cotton bag, and is ready for the market.

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(3) Thirdly, the intrinsic value of a gold-filled case based upon its gold content? If the above examples are reasonably accurate, basic math would indicate that the gold content value of a one troy ounce 14K gold-filled case is approximately $186.67 in today's marketplace (1 oz. x $560 x 14/24 x 4/7). Of course, one would have to discount the gold content based upon the amount of wear to the case. Does this make sense or am I missing something? Confused

As always, thanks for the education. Smile

Ted
 
Posts: 106 | Location: Highland, Kansas in the USA | Registered: January 01, 2006
posted
Ted,
It sounds like you are well on your way to finding out quite a bit about cases...


The Ehrhardt book you speak of is 'Trademarks'...
It is a general reference showing different case markings and to whom the mark is acredited... and is not complete by a long shot.

As a 'General' reference, the section in Shugart's books... current volume or past... is fairly adequate...

A better source is the Neibling book on case makers, very difficult (almost impossible) to find a copy at a 'reasonable' price.

On the manufacturing... remember if this thickness of billet is a starting point... the yield of case sheet is very great... compare the relative thickness of the cases with the dimensions of the billets before rolling...


To ME... a 'value' of a GF case is

1. Condition...
2. Design
3. Condition
4. engravings, etc
5. Condition
6. quality... "10, 15,20,25, year", Permanent, etc....
7. Condition
8. Appropriateness of the case to a given movement (era, etc)
9. Condition....


Of course there are those that value cases higher than I do ........ Big Grin i am cheep....

These cases do have value for gold content... The smelters have the value down to a science...

And other members are more versed in this aspect than I ... I yield the floor.........

.
 
Posts: 1496 | Registered: November 20, 2002
posted
Thanks, Terry.

Anyone else have other thoughts or information sources on cases?

Ted
 
Posts: 106 | Location: Highland, Kansas in the USA | Registered: January 01, 2006
posted
Ted, let's see if I can help you out on gold value of gold filled cases. WORN OUT gold filled cases generally have a scrap value of around 20-30 cents per gram or around 9-10 dollars per ounce, due to the remaining gold in the case that never gets worn. A 16 size open face case would generally weigh around 30-35 grams so the case has a scrap value of around 6-12 dollars worn out. NOW, when NEW the total gold in a new gold filled case would only total around 3-5 grams of PURE gold. Remember the sheet of gold that is rolled and pressed into the case is either 10 or 14K NOT pure 24K gold.

Also, the information you are reading on the thickness of the base metal and the gold sheets if BEFORE it was rolled out and under tons of pressure it changes thickness dramatically and spreads as well. Of course the gold would compress much more than the composition metals due to hardness and softness ratios of the two different metals as well. You may read in old catalogues that a gold filled 16 size case in say 1910 was around 6-9 dollars. Gold was only 20 dollars per ounce then, so you can easily calculate that they were not going to sell at a loss, so including workmanship one can easily conclude there was not much gold in a gold filled case.

An easy rule of thumb for any gold filled case , 20,25,30 years warranty, is that there is only 1/8 of an ounce of PURE 24K gold in a gold filled case once it's assayed out, so with gold at 550 per ounce today, the value of the PURE gold content in a new gold filled case is only around 50-80 dollars depending upon whether it was alloyed to be a 10k gold filled case or 14K gold filled case when new. You may find a cheaper gold filled case having only 30 dollars worth of gold in it or a real nice heavy one having 100 if you run up on a nice early , heavy, triple hinge permanent example like new, but generally speaking, you're looking at around 70 dollars of PURE 24K gold in the case when new on AVERAGE. It's a bit complicated but I have friends who are pawn brokers and I play around with it enough to understand how to figure gold a bit.

However, with the prices that near mint cases are bringing these days, I hope you are not considering scrapping one, as it will bring a lot more right here on 185, ha!. Hope this helps you a little. Happy "Gold Filled" Hunting!
 
Posts: 230 | Registered: January 11, 2003
posted
Mike,

Your explanation makes a lot of sense and I thank you for the same. I am quite familiar with the difference between "pure" 24K gold, "solid" gold, gold-filled, etc., having collected coins for many years.

What is confusing is the manner in which Shugart & others describe the gold-filled case-making process. The dimensions of the composition metal & the solid gold which are welded together prior to the flattening process cannot be the same , as oftentimes described and as described in Shugart . In fact, though the depth of the metal prior to the flattening may or may not be the same, the length & width cannot be. Your explanation that the softer solid gold compresses more (and flattens out to cover a much larger area) is quite logical and confirms my suspicions. This is why I broached this topic. I am going to make a suggestion for a better explanation to the Shugart authors through the IHC 185 link.

By the way, I'm not into scrapping cases, just trying to learn more about them and their value. IHC 185 is a great learning experience for me & I appreciate the willingness of people like yourself to share their knowledge! Thanks again.

Ted
 
Posts: 106 | Location: Highland, Kansas in the USA | Registered: January 01, 2006
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