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RECIPES.
The following are old workshop recipes.
It is unlikely that all the ingredients could be purchased today, and there are many modern substitutes which will be more
effective, and in many cases, far less dangerous.
Waterproof glue. Add 3 pints of skim milk to 1 lb. of glue.
(Yes, you can still get the old type of glue which has to be heated in a glue-pot and used hot. Although Croid Aero Glue (one of the best known) is no longer available, Pearl glue can still be bought. To use, pour approximately the required quantity of glue into the inner container, add hot water to just cover the glue, and leave for several hours. Then put water in the outer container, and heat until the glue is liquid with no lumps remaining. Whilst the water in the outer container can boil, the glue must not. The thickness of the glue will determine the drying time. It is ideal for veneering and restoring antique furniture.)
To join steel or iron, take ¼ ox of flouric acid, add 1 oz. Of iron filings and oz. Brass filings. Mix acid and filings and coat on parts to be joined. Clamp and leave until set.
< Flouric acid is now called hydrofluoric acid. It is extremely dangerous, and also less effective than modern glues.>
1 lb. or carbide generates 4.5lb of acetylene.
A filler for gaps or holes in steel or castings can be made from 5% sulphur, 85% cast iron siftings and 10% sal-ammoniac.
( It is worth remembering that this used to be quite common, so if you are restoring any old machinery etc, do not be surprised to find holes full of filler.)
A paste to seal steam joints can be made from white lead ground in oil to which one adds black oxide (manganese) and a small amount of litharge (according to the OED, a red or yellow mineral form of lead monoxide), and a little linseed oil if the mixture is too stiff.
To keep brass components looking polished, coat them in a solution of shellac dissolved in alcohol
Blackening steel. 1.
Make up the following 2 solutions.
A, 4-1.2oz sodium hyposulphite + 40 oz water.
B, 1-1/4oz lead acetate + 40oz water.
Clean the article with caustic soda, warm them and brush with a solution
composed of equal parts of A and B, the solution to be boiled before use.
Allow to dry in a warm place, then polish with boiled linseed oil.
Blackening steel. 2.
For a blue-black finish,
onto the previously cleaned surface, brush a solution consisting of 2 parts
of crystallised chloride of iron + 2 parts solid chloride of antimony + 1
part gallic acid + 4 to5 parts water.
Allow the part to dry, then repeat 3 or 4 times.
Blackening steel. 3.
For a brown-black finish.
First brush the clean surface with a copper-sulphate solution. Wait a few
minutes then wipe dry, and then apply a solution of ammonium sulphide. After
30 seconds, dry with a clean cloth.
Blackening steel. 4.
Also for brown-black,
Give several coats of the following solution.
1 oz. copper sulphate + 1 oz sweet spirits of nitre + 1 pint distilled
water, allowing several hours between coats.
For a blue finish on steel.
Coat the item in a hot liquid saltpetre, and a more even coating may result if the saltpetre is dissolved in water to make a saturated solution beforehand. Leave for a time, and then allow to cool and wash thoroughly. The solution should be as strong and as hot as possible.
Note, this can cause serious burns if allowed to get on skin.
Looking through an old model engineering book I found the following:
" The metal parts were lightly copper plated, and then oxidised by immersion in a solution of liver of sulpher, which gives an excellent grey-black finish."
According to Mike Tilby, "liver of sulpher is" a hard brittle liver-brown substance with a nauseous alkaline taste. Soluble in water and odour of hydrogen sulphide.
It is a mixture of potassium polysulphides and thiosulphate obtained by heating potassium carbonate with sulphur.
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