Conair SC-5 manual Cutter bushing bore surface quality, C-2 APPENDIX, All About Cutter Bushings

ALL ABOUT

CUTTER

BUSHINGS

Supportive bushings become more important if heat is used to minimize whitening (fracturing).

●If you are cutting a square or rectangular profile, whether rigid or flexible, a round bushing bore will not offer proper support and will often lead to an "S" shaped cut. A flat bottomed bushing will offer excellent support and enhance the shearing action of the blade.

●In the case of flexible extrudates, allow 0.010-0.050 in. clearance depending on durometer and surface; the softer durometers and tacky surfaces require the most clearance. In the case of softer durometer materials, bushing lubrica- tion may be required to minimize drag and material build- up between the cutter bushing faces.

Cutter bushing bore surface quality

The internal surface of the cutter bushing must be smooth and glass-like when cutting flexible extrudates, otherwise exces- sive drag causes jamming and can lead to variations in cut-to- length accuracy.

●When cutting flexible materials, have the internal sur- face machined to resemble glass. In many cases, med- ical processors will actually have the ID of their bush- ings either honed or burnished for best results.

●When cutting clear extrudates, it is also very important to have a smooth internal surface to minimize scratch- es. In some cases it may be necessary to make a Teflon or Delrin insert to further minimize drag and/or scratch- ing.

●Bushing lubrication can also help minimize bushing drag.

●Be sure to have a lead-in angle machined into the entrance of the upstream cutter bushing. The transition from the bore to the lead-in angle should not be abrupt as it to can cause variable drag.

C-2 APPENDIX ALL ABOUT CUTTER BUSHINGS UGE059/1003