Transcriber’s Notes:
Bold, italics, superscript and subscript text have been trancribed as
=text=, _text_, ^{text}, and _{text}, respectively. Small capitals
have been replaced with capitals. Letters between square brackets such
as [T] and [V] indicate T- and V-shaped symbols rather than letters.
More transcriber’s Notes may be found at the end of this text.
Soldering, Brazing
and Welding
EDITED BY
BERNARD E. JONES
Editor of “Work”
With 78 Illustrations
[Illustration]
FUNK & WAGNALLS COMPANY
NEW YORK and LONDON
1917
EDITOR’S PREFACE
This handbook, which explains in detail a variety of processes common to
general metalworking, has been written by a number of thoroughly
practical men, by whom it was contributed in another form to “Work,” the
illustrated weekly journal of handicrafts and mechanics. Its appeal is
to everybody who makes any attempt at working in metals, inasmuch as at
least one of the processes--soldering, brazing or welding--will be met
at a very early stage in the beginner’s experience. This handbook will
be found a complete workshop guide to the usual methods of soldering and
brazing, and will form an excellent introduction to the modern
electrical and oxy-acetylene welding processes, to do complete justice
to which, however, a separate handbook would, of course, be necessary.
If readers encounter difficulty in any of the matters treated in this
book, they have only to write to “Work,” in whose columns (but not by
post) help will be willingly afforded.
B. E. J.
CONTENTS
CHAPTER PAGE
1. VARIOUS PROCESSES OF JOINING METALS 1
2. SOFT SOLDERS 4
3. FLUXES USED IN SOFT-SOLDERING 12
4. SOFT-SOLDERING WITH THE COPPER BIT 17
5. SOFT-SOLDERING WITH BLOWPIPE OR BUNSEN BURNER 37
6. SOLDERING ALUMINIUM 57
7. WIPING JOINTS ON LEAD PIPES 64
8. HARD-SOLDERING WITH SILVER SOLDER 75
9. SOLDERING GOLD AND SILVER JEWELLERY 83
10. BRAZING 89
11. WELDING IRON AND STEEL UNDER THE HAMMER 108
12. MAKING BLOWPIPES 112
13. MANAGING BLOW-LAMPS 118
14. MAKING BLOW-LAMPS 122
15. ELECTRIC AND THERMIT WELDING BRIEFLY CONSIDERED 129
16. OXY-ACETYLENE WELDING 134
17. LEAD-BURNING 150
INDEX 155
SOLDERING, BRAZING AND WELDING
CHAPTER I
The Various Processes of Joining Metals
Apart from the use of rivets, screws, etc., metal is commonly joined by
soldering, brazing, or welding, three groups of processes that have one
thing in common--the use of heat to fuse either the metals themselves or
an alloy which is interposed to consolidate the joint. The word “solder”
is derived through the French from a Latin word meaning “solid.”
Soldering may be “soft” or “hard.” Soft-soldering uses lead-tin alloys
which are easily melted in a bunsen gas flame or with a hot iron or bit;
while hard-soldering employs a silver-copper alloy, to melt which a
mouth blowpipe at least is necessary. Brazing is hard-soldering with
spelter (brass), and a forge or a heavy blowlamp or a powerful blowpipe
must be employed to provide the heat.
Welding is a fusion process which in the past was almost entirely
confined to wrought-iron and steel, these metals possessing the property
of weldability to an extent unknown in the case of any other metals.
The blacksmith’s process of welding is to heat the iron or steel until
the surface of the metal becomes pasty, and then to bring the two pieces
into intimate contact by hammering on the anvil. Of late years the
welding of iron, steel, copper and some other metals has been rendered
possible by the use of certain electrical and chemical methods and--most
important of all--by the use of the oxy-acetylene blowpipe, the process
being known as “fusion welding” or “autogenous soldering,” the word
autogenous implying that the process is complete in itself and
independent of the use of any extraneous substance such as solder. The
thermit process, of which so much has been heard, and which is briefly
dealt with later, is the fusion welding of iron and steel by means of
the intense heat produced by the combustion of a special chemical
compound. Perhaps the oldest of the autogenous soldering processes is
“lead-burning,” in which the flame of an airo-hydrogen blowpipe is
brought to bear upon the lead, the joint being fed with a strip of the
same metal.
Soft-soldering is an operation that the beginner will not find nearly so
difficult as hard-soldering or brazing, and although the strength of
joints made by it is not nearly equal to that produced by the methods
named, it fills a useful place within its scope. It is purely a surface
union--that is, the solder adheres to the faces in contact in much the
same manner as an adhesive sticks to metal; but with the assistance of
fluxes, the contact is made so intimate that some force is necessary to
break the joint. Soft-soldering is also of use where brazing would
simply mean the ruin or destruction of the metals, as in the cases of
lead, poor-quality brass, pewter, tin, zinc, and in tinplate and
galvanised iron.
In silver-soldering and brazing, the silver or spelter that fuses to
form the joint alloys itself so intimately with the copper or brass that
it actually becomes part of the piece itself, and for all practical
purposes cannot be distinguished from it. But soft-soldering is not
always inferior to hard-soldering. Indeed, the surface nature of the
soldering often constitutes its value.
The strongest joints of all are produced by fusion welding, as will be
duly understood from later chapters.