Part 1: Manufacture of Special Tools
Figures 1-3 explain the manufacture of special tools. They are an essential help in order to simplify the manufacturing technique for D.S.L.T. prostheses and should be available before work starts.
Chamfering Blade
Figure 1: Manufacture of chamfering blade
The chamfering blade is a special tool for chamfering the glue edges of the PE foam (PE-lite, Tepefoam etc.). It will simplify the working procedure of chamfering, providing neat processing of glue edge of the soft liner.
If a sanding drum (or, perhaps a grinding stone) is available or if chamfering manually with a sharp knife is familiar to you, you will not need this tool. For persons with less practice, it will be an essential help.
The best cutting results are obtained by using a slightly tilted blade (e.g. put a match underneath in order to alter the cutting angle).
At first, practice with some waste pieces is suggested.
Application of the tool is explained in more detail in Fig. 7.
The blade should be covered by a blade cover when not in use in order to avoid injuries.
Moulding Tool
Figure 2: Manufacture of moulding tool
Later on in the process, the moulding tool is needed in order to functionally shape the tendon bar and the contours of the patella.
The socket tends to form cavities at this point which are unfavorable for a good fit. With this molding tool, these disadvantages will be avoided.
It is prepared from sheet metal of 2 mm thickness corresponding to the example shown, bent to a U, and strengthened along the edges (e.g. by means of a plastic tube or a glued-on PE-lite reinforcement). This reinforcement also eliminates sharpness of the edge.
For every patient, the shape of the tool must be adjusted afresh. If necessary, some remaking or rebending is carried out in order to achieve an individually perfect fitting form. Application of the tool is shown on Fig. 43.
Glueing Aid
Figure 3: Manufacture of glueing aid
Later on in the process the glueing aid is needed in order to glue the edge of the PElite cone to the soft, liner in a relatively simple and neat way. It is a trapezoidal wooden bar with rounded upper edge. The measurements are standard and for most soft liners they should be suitable.
During the manufacturing procedure, the glueing aid, at its broader end, is fastened onto a bench-vice. If you have sufficient experience in free-handed manual glueing of soft liners you will not need to prepare such a tool but for those with less practice it is an essential help.
Application of this tool is shown in more detail in Figures 10 and 11.