TUB-SIZING

295

adhere to the surface and stand out prominently after passing over the drying
cylinders.

Opinions differ as to whether the paper should be reeled up after sizing and
allowed to stand and soak for a time before being dried. It is the practice in
some mills to have several reels lying sized for some hours before drying, while
others allow the reel to soak while the previous one is being dried; others,
again, run the paper straight from the tub over the dryer.

So far as the efficiency of the sizing is concerned, there seems to be little to

[Messrs. Masson, Scott and Co., Lid.
FIG. 127.—TUB-SIZING VAT AND SQUEEZE ROILS
choose between the various methods, and our experience leads us to the con-
clusion that the latter method—namely, running the paper straight through the
tub and over the dryer—is the most economical and convenient, although it
means that the sizing and drying must always be done at the same speed.
Nevertheless, by this method we have sized papers in the same tub vary-
ing in substance from Large Post 7 Ib. to Large Post 35 lb., with excellent
results.
The second method seems a waste of time, as that part of the paper which
has just left the tub is the first to pass over the dryer, and consequently one end
of the paper will have been soaked for an hour or more while the other will
be fresh from the tub.