5.17.
TROUGH CONSTRUCTION
165
Instrument Products Division
E. I. duPont de Nemours 8c Co. (Inc.)
Wilmington 98, Delaware
Ge-Fe-Ri, Soc. r. 1
Via Marittima I, 146/G
Frosinone, Italy
Walter Rawyler
Pieterlen, (Switzerland)
Hauptstrasse 25
Ernst Leitz
Wetzlar
Germany
5.17. Trough Construction
After a satisfactory glass knife has been prepared, the next step is to
construct a trough. When this is filled with a suitable fluid (usually a
dilute acetone solution) which wets to the knife edge, sections are floated
as they are cut. (Diamond knives are permanently mounted in a holder
which incorporates a trough.)
The simplest way to prepare a trough is to use an adhesive tape and
wrap it from one side to the other as illustrated in Fig. 18. Excess tape
overhanging the face of the knife is carefully cut away with a razor taking
great care to avoid contaminating the cutting edge or the front face of
the knife.
In making the trough, the knife should be mounted for convenience in
some sort of a vise. Its front face should be vertically oriented, then the
top edge of the trough can be accurately aligned at right angles to this by
holding and pulling the tape horizontally. A correctly designed trough
then is made almost automatically.
It is a mistake to make too large a trough. It will become apparent
later in this chapter that sections can be handled most easily if they are in
a rather confined space. Therefore, rather narrow adhesive tape should be
used so that it does not extend far along the back of the knife. If the knife
angle is approximately 45°, the tape should not be more than ^ in. wide,
and preferably about § in.
TROUGH CONSTRUCTION
165
Instrument Products Division
E. I. duPont de Nemours 8c Co. (Inc.)
Wilmington 98, Delaware
Ge-Fe-Ri, Soc. r. 1
Via Marittima I, 146/G
Frosinone, Italy
Walter Rawyler
Pieterlen, (Switzerland)
Hauptstrasse 25
Ernst Leitz
Wetzlar
Germany
5.17. Trough Construction
After a satisfactory glass knife has been prepared, the next step is to
construct a trough. When this is filled with a suitable fluid (usually a
dilute acetone solution) which wets to the knife edge, sections are floated
as they are cut. (Diamond knives are permanently mounted in a holder
which incorporates a trough.)
The simplest way to prepare a trough is to use an adhesive tape and
wrap it from one side to the other as illustrated in Fig. 18. Excess tape
overhanging the face of the knife is carefully cut away with a razor taking
great care to avoid contaminating the cutting edge or the front face of
the knife.
In making the trough, the knife should be mounted for convenience in
some sort of a vise. Its front face should be vertically oriented, then the
top edge of the trough can be accurately aligned at right angles to this by
holding and pulling the tape horizontally. A correctly designed trough
then is made almost automatically.
It is a mistake to make too large a trough. It will become apparent
later in this chapter that sections can be handled most easily if they are in
a rather confined space. Therefore, rather narrow adhesive tape should be
used so that it does not extend far along the back of the knife. If the knife
angle is approximately 45°, the tape should not be more than ^ in. wide,
and preferably about § in.