Jewelers Drill Press

it is properly done. In sweating two pieces of steel together, each piece is tinned, (giving a thin coating of solder) then the pieces are placed face-to-face with the tinned surfaces in contact, are clamped tightly in this position and are then heated with a torch so that the pores of the steel are well opened by the applied heat, whereupon the solder enters these pores making a good joint between the two pieces. The pieces are left clamped together while cooling. This last is a point to be remembered in either soldering or sweating, keep parts stationary and together while a soldered or sweated joint is cooling, for any movement of one piece independent of the other being joined to it causes the solder to crystalize in the joint and when this happens its holding power becomes negligible.

In sweating parts together the two surfaces that are to be joined should make as perfect a contact with each other as possible, so contours of the two surfaces must match to produce a good joint. These surfaces must also be clean and not too highly burnished. They may be scraped with a knife or scraper, filed, or a medium coarse carborundum cloth may be used to free the surfaces of any corrosion. They must be jree o) any grease also.

After the surfaces are cleaned they are coated with a flux to prevent oxidation. For steel, either one of two fluxes will answer the purpose. One of these is rosin, usually used in powdered form. It is spread upon the surface to be tinned and the heat of the iron used in tinning the surface melts the rosin and flows it completely over the surface. Rosin is the flux to be used where all danger of rust forming must be avoided.

The second flux for steel is zinc chloride, made by dissolving zinc chips or cuttings in hydrochloric acid. To prepare it, put all the zinc the acid will dissolve into the acid. This flux is applied with a stiff brush such as supplied with small bottles of glue. This flux will cause corrosion and rust on surfaces adjacent to the sweated or soldered joint, so these surfaces should be well washed with water or ammonia after the parts have cooled, which prevents this.

The soldering copper, or "iron," used in tinning surfaces should be a large size, such as the two pound iron, for the solder should be well rubbed into the surface of the steel by the iron and to do this the iron should retain its heat for quite a period of time, which a small iron will not do.

The soldering copper should comc to a point and the sides of this point should be square and flat. The

Jewelers Soldering Iron

Position of soldering iron for tinning a barrel surface, preparatory to fitting a ramp sight.

iron should be well tinned upon these sides at the point. This tinning is a coating of the iron with solder and is best clone with a block of sal-ammoniac. The iron is filed until the point and surfaces back of it are clean and smooth. It is then heated, hot enough so that when applied to the sal-ammoniac the latter fumes and smokes, melting under the temperature of the iron. Small pieces of solder are dropped onto the block of sal-ammoniac and the hot iron is rubbed upon these so that the iron has a coating of solder upon it.

Jewelers Drill Press

Plate XVIII

Using a jeweler's lathe, set vertically, as a sensitive drill press for very small drills- A lever action, tail .stock spindle is fitted up as shown and u small Jacobs drill chuck uf 0 lo Vh" capacity is used.

In heating the soldering iron avoid overheating it, as this will burn and roughen the surface of the iron, forming a scale upon it through which the heat does not pass very well to the surface being soldered. If overheating occurs, the iron must be filed clean again and retinned. After heating an iron, just before applying it to the solder, it should be dipped into a liquid flux such as the zinc-chloride as this brightens it and enables it to hold more solder upon its surface.

In sweating two pieces of steel together, such as sweating a ramp or barrel band onto a barrel, all blueing must be removed from the barrel surface and from the inner surface of the ramp or band if it is already blued. Put the ramp or band in place on the barrel and mark around its surface with a very sharp scriber, such as a phonograph needle. Remove the ramp or band and, using a small scraper or file, remove all blueing from the barrel within the scribed lines. If the ramp or band is blued on its inner surface, also scrape all blueing off of this surface that comes in contact with the barrel.

Have the soldering iron good and hot and, applying the flux to the cleaned surface of the barrel, dip the soldering iron into the zinc-chloride flux, then touch it to the solder and apply it to the fluxed surface of the barrel, holding it in one place until the barrel surface heats up, then rubbing it around at that point so that the solder is well rubbed into the surface. Gradually extend the rubbing process as the barrel continues to heat, until the barrel is well tinned with solder within the scribed lines.

The barrel band, or the ramp if it is equipped with a band that encircles the barrel, may be too small to be tinned on the inside with the large iron, although the point of the large iron should reach all parts inside the band. If this large iron is too big a smaller one should be used.

After both parts have been tinned, heat them with a torch and use a cloth to wipe off the excess solder when the torch flame has softened it sufficiently. Place the ramp or band upon the barrel in proper position and, if the item is a ramp, place a piece of sheet-copper on the tail and put a clamp upon it, to draw the tail down tight to the barrel. If the item is a tightly-fitted barrel band and was properly fitted before being tinned, this will probably not drive quite up to place until it is heated, so the contraction of the band itself will make a clamp unnecessary upon it. Apply the heat with a torch to the item being sweated on the barrel and heat it as evenly as possible until the solder begins to run at. the edges, then if a clamp is used tighten up the clamp a little more and hold the heat on the job a moment longer, then shut it off and let the job cool without moving it.

A method of tinning small parts, as the inside of a ring too small to get into with any soldering iron at hand, is to heat the piece in a torch flame, after applying flux, and then apply wire solder to the surface to be tinned, turning the piece so that the solder coats the entire surface in good shape. Either acid-core or rosin-core wire solder will work the best for this job. An acetylene torch, using the gas acetylene only and no oxygen, is very good for these soldering and sweating jobs as the acetylene combines with oxygen in the air and burns it, preventing oxidation of the surface to be soldered.

Brazing is a method of joining two metals with molten brass. It requires a much higher heat than soldering, as the metals to be joined must be hed-hot, so its use is limited to parts which will not be injured by the high heat required. The joint made by brazing will stand a pretty heavy strain, so long as it is not a bending strain at the point of joining.

Silver soldering or hard soldering is often confused with brazing but there is a difference between them, because while brazing uses molten bra3S, which brass will become molten at about 1660 degrees Fahrenheit if it is the standard type spelter (which is really half copper and half zinc), silver-solders may be had in mixtures requiring heats of from 700 or 800 degrees Fahrenheit to 2000 degrees Fahrenheit to become molten.

Brazing requires the heat of the acetylene torch to accomplish a good joint, as the steel or iron parts to be joined must be brought to a good red-heat at the

Infow Red Heat Guns

Brazing a block to a barrel band.

joint. The parts to be joined must be thoroughly clean and as they are brought up to red-heat, borax in powdered form is sprinkled upon them to act as a flux. This will melt and cover the surfaces and the brazing spelter, in the form of fine filings or melted from the rod by the torch, is applied to the joint, where it will run into the smallest crevices. In doing the work the job should be turned so that the molten spelter can be run in from all sides. The borax used as flux will form a hard scale and may be ground- off if there is excess material to be removed from the finished joint, or it may be removed by placing the piece in an acid pickle of one part sulphuric acid to twenty parts of water.

Neither brazing or hard soldering are processes suitable for attaching parts to barrels or receivers, for even if the bore of the barrel is protected by file-hardening compound or something else to prevent oxidation under the high heat, the heat may cause the barrel to develop a kink in it. Heat treatment will be removed from receivers by the necessary heat for brazing or hard soldering, and the part will have to be reheat-treated. Brazing or hard soldering are suitable however for making or repairing parts removed from the gun if the joint is not visible when the part is in place, as the brass in the joint will show and cannot be blued successfully.

An example of a brazed joint in gun work is the brazing of a block of steel onto the bottom of a barrel band, so that a screw or swivel passed through the forearm will screw into the block, as in this case the joint is entirely concealed by the forearm. Another example is the brazing of the barrel lugs onto the bottom of shotgun barrels. Box magazines made of sheet-steel and entirely concealed within the stock may be made by brazing the sheets together or a bar may be brazed between the tangs of a gun into which a bolt passed through the butt may be screwed.

Silver soldering or hard soldering is done with a silver-brass alloy, usually supplied in fine granular or thin ribbon form. As mentioned above this may be obtained in alloys with various melting points. The ribbon form is usually the best to use, as a piece of the ribbon is placed between the two parts to be joined, after they have been thoroughly cleaned and then coated with a paste made of borax mixed with water.

The parts are then clamped tightly together and the heat is applied until the silver solder melts. The parts are left clamped together until thoroughly cool, after which the borax scale is removed by placing the parts in the acid pickle mentioned above. Very little, if any, of the white silver solder will show at the edge of the joint if the pieces are well fitted and, as this is less objectionable than the brass color of a brazed joint, the silver soldering is preferred for joining parts in gun work where the joint remains in sight. This method can be used to repair broken tangs, such as shotgun tangs, although if a good welder is available the job had better be welded. Brazing or hard solder ing requires less skill and knowledge of metals than welding requires, so in some localities where good welding shops arc not available the brazing or silver soldering may be used. Jewelers are usually very good at brazing anything within the capacities of their equipment, and pointers may be picked up from them.

Jewelers Drill Press

Silver soldering a block to a barrel band.

Woodworking Tools and Installation Tips

Woodworking Tools and Installation Tips

There are a lot of things that either needs to be repaired, or put together when youre a homeowner. If youre a new homeowner, and have just gotten out of apartment style living, you might want to take this list with you to the hardware store. From remolding jobs to putting together furniture you can use these 5 power tools to get your stuff together. Dont forget too that youll need a few extra tools for other jobs around the house.

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Responses

  • semhar
    Why is sweating preferred on shotgun barrels over hard soldering and brazing?
    8 years ago

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