Music Trade Review -- © mbsi.org, arcade-museum.com -- digitized with support from namm.org
THE MUSIC TRADE REVIEW
67
SOME CAUSES OF GLUE^FOAMING AND THEIR REMEDIES
Some Simple Hints Whereby Piano Manufacturers Can Prevent the Annoyance and Waste
Caused by Glue Which Foams—How to Detect the Presence of Grease in Glue
Glue foaming is a source of considerable annoy-
ance, which some users seem unable either to over-
come or to account for. High-foaming glues are
especially objectionable when applied with power
glue spreaders or by other mechanical means. In
such cases the roll agitates the glue solution to such
an extent that a frothy mixture of glue and air is
the result, with a consequent reduction in the bind-
ing power of the glue. Foam in glue usually arises
fiom the incorporation of minute bubbles of air
with the solution when this is beaten rapidly.
Again, foam may be caused by the presence of
mucin, a substance existing in the raw glue stock
(which, however, can be removed by proper wash-
ing) and by soaps formed in the process of manu-
facture by overliming. There may be present in
the glue solution substances which render the emul-
sion more or less permanent, or the emulsion may
be only temporary, the foam receding and disap-
pearing in a few moments. The same defects
which fictitiously increase the viscosity of glues
contribute materially to the foam in glue. For this
reason the viscosity test of a glue solution should
not be depended upon, unless other tests are made
in determining glue quality.
Glue that is overcooked or overheated while dis-
solving is very liable to foam. Too much care can-
not be given to the subject of dissolving glue. The
best glue may be injured to the extent of several
cents per pound by dissolving at too high a tem-
perature or by keeping it in a sustained heat. There
is no necessity for heating glue to a higher tem-
perature than 159 deg. F., and if the wood is prop-
erly warmed at the time of gluing up, the tempera-
ture of the solution need not be over" 120 deg. F.
The fallacy that glue must be used boiling hot is
rapidly being exploded, but none too soon for the
benefit of the glue room and its work.
Many glue men aie of the opinion that glue
should not contain a particle of grease, as that
would impair its adhesive quality, but such is not
the case. The quantity of grease, of course, must
be very small, but a small quantity is necessary to
prevent foaming in the spreader. A simple test for
grease may be made as follows:
Make a thin solution of the glue to be tested, say
a ten to one solution, and stir thoroughly through it
a small quantity of lampblack. Take a clean brush,
and while the solution is yet hot spread some of it
on a sheet of clean white paper, making only one
stroke of the brush. If there is grease in the glue
it will separate itself from the lampblack and show
up in small white particles over the surface. This
will not give the percentage of grease, but if there
is any to be seen there is sufficient. If there is none
to be seen, about one-eighth ounce of beef tallow
to a gallon of glue mixture might help out.
There are a number of methods for testing foam
in glues which are in common use. Fernbach's
method is widely used, and proves very satisfac-
tory. To make the Fernbach test, a solution of
twenty-five grams of glue and 100 cubic centimeters
of water should be made (a 25 per cent, solution).
The Ohio Veneer Co.
CINCINNATI, O.
Importers and Manufacturers of Figured
Mahogany and Foreign Woods for high-
grade piano cases and cabinets.
York Office and Sample Room ==
Grand Central Palace Bldg.
Lexington Ave. and 46th St.
G. H. VAUGHAN, Eastern Representative
illllllllll
George H. Harper Co.
Orange, N. J.
The solution is poured into a glass vessel, wide
enough to accommodate the usual size of rotary
And when you're satisfied
egg beater. This vessel should be neither so thick
that
we've the best punch-
that the heat of the solution will crack it, nor yet
so thin that it is apt to be broken by the egg beater.
ings on the market, cut
On the side a mark should be placed at the level
clean and accurately from
of the glue solution, and above this three other*,
the best of material in cellu-
one-half inch apart. The egg beater is slowly
rotated in the solution for half a minute, and the
loid, cloth, felt, fibre,
quality as well as the quantity of the foam noted.
leather, paper, rubber or
If this is only slight and disappears in a moment,
whatever you want, give
the glue is non-foaming; if somewhat more per-
manent and reaching the second line, the glue is
us credit and send your
slightly foamy; if the column of foam reaches the
orders to
third mark and takes some time to recede, it is
moderately foamy, and so on. The solution should
not be agitated too rapidly or too long, as, under
these conditions, any glue solution will emulsify.
The test conditions should be approximated to those
obtaining in actual work. Two revolutions of the
egg beater per second,will suffice for the test. To
T
secure comparable result i it is absolutely necessary
that the glues under test be kept at a nearly fixed
temperature.
NEW YORK
Glue that is old or sour will foam, and glue soon
sours in a sustained heat. When it has reached THE PROPER FILLER FOR MAHOGANY
this condition the only remedy is to throw it away.
It cannot be made good by mixing good glue with An Easy Working-Filler Which Can Be Easily
Made and Which Produces Good Results
it, no matter how small the quantity of bad glue.
If good glue and bad glue are mixed the effect is to
The only filler which should be used for oak
make the good glue bad, too. Not a particle of old or mahogany is one that will work easily, as a
glue should be carried over for use from one day filler that works hard is most certain to pull
to another, and every utensil should be thoroughly out of the pores of the wood during the process
cleaned out at night or before using in the morning, of cleaning off. A very good filler for this
as is most convenient. A little bit of old, rotten class of work can be made by stirring one part
glue will set up the process of disintegration in of turpentine, three parts each of brown and
operation, which, started in the morning, will be black Japan, and six parts of pure boiled linseed
pietty far advanced by the end of the day. To say oil, until they are thoroughly mixed. A mixture
nothing about the trouble from foaming, this dis- of one part of Van Dyke brown to twelve parts
integration means much loss in value where con- of silex should be added to the mixture until
siderable glue is used.
it assumes the consistency of a stiff dough. It
It is a very easy matter to have everything in should be allowed to stand for at least twenty-
the glue room clean, especially when it is kept four hours before it is used. To prepare this
clean. But if things are allowed to get filthy, the dough, or paste, for use, the desired quantity is
job of making clean becomes hard and filthy. For put in a pail with a little benzine and broken
cleaning machines the steam jet may be used, while up with a stick. A small quantity of benzine
the smaller utensils may be dropped into a vat of should be put in first, adding more benzine until
the filler is reduced to the desired constitu-
water and they will be clean by morning.
Some glues are made expressly for brush work, ency. The filler is brushed well into the pores
and will give no trouble when used that way. In of the wood and allowed to stand until it is
buying glue it is well to advise the supply man as thoroughly flat before it is cleaned off. It will
to how the glue will be used, thereby enabling him harden perfectly in about twenty-four hours,
to furnish a glue that will meet the proper re- but a full day should be allowed between the
time the wood is filled and the time it is shel-
quirements.
A poor glue will usually foam easier than a high- laced.
grade glue, but that does not mean that all glue
that foams easily is of a poor quality. Many high-
grade glues, intended for brush work, have all the
grease taken out, and if they are used with the brush
there is nothing put in to take the place of the
BRANCH OFFICES:
grease. When they are to be used in the spreader
Chicago
iHINGJSS 160 No.
a small quantity of cocoanut is put in to prevent
Fifth Are.
foaming.
'Out of sight,
While all glues that foam may not be of poor
S-3 Francisco
ever in mind"
quality, still a foamy glue should never be used.
164 Ilansford Blo«.
When you fail to see an un
Foam will not hold veneer down, and if the glue
sightly hinge protruding you
Know " Soss" is the answer.
Let Angeles
shows a tendency to foam the work should be
Soss Hinges emphasize beau-
221 Central Bids.
tiful
wood
finishes
as
there
is
stopped and the cause of the trouble should be
no projecting metal on either
ascertained and remedied. If all the requirements
, side of the door.
T,!k3neapolis
Made in numerous sizes.
for the proper use of the glue have been complied
3416 Second Ave..So-
Illustrated Catalog S
with the trouble should be referred to the manu-
mailed on request.
Detroit
facturer. If, however, it is absolutely necessary to
n
David Whitney Bids.
For
make temporary use of glue that is foaming, a
Further
Intormatton
small quantity of methylated spirits will greatly
improve its keeping qualities, at the same time
SOSS MANUFACTURING CO.
obviating to a certain extent the tendency toward
435 443 ATLANTIC AVE BROOKLYN.N.Y
foaming.
C.F GOEPELCYCD
137 E A t f I3 -* ST.
INVISIBLE
VENEERS
Circassian Walnut, Oak, Walnut
and Specializing on Mahogany.
Capacity—5 Million Feet