UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Cutting accurate holes in thin plastic sheet.

Nanozeugma · 2nd Mar 2022, 1:50 pm

Hi all,
I'm in the process of attempting to fashion a replacement drum cover, bearing station names, to replace a damaged original for a Murphy A48.
Thanks to the kind efforts of Jerry (cathoderay57) I now have an accurate reproduction (template) of the station names.
I haven't yet decided whether to use clear PETG sheet with clear self adhesive printed film on the back, or just use OHP film.
Now the problem.
Having marked the hole centres, four per side, where the cover is attached to the metal support frame, I'm struggling working out how to punch the holes accurately (in the right place.)
I have a rotary punch which goes up to 4.5mm, and a standalone 5mm steel punch.
The issue is that I cannot see what I'm doing, trying to align the punch over the proposed hole centres, marked on the material with an indelible marker dot.
I wonder if there is a simple answer to punching the hole(s) in the right place that I may have overlooked?

2nd Mar 2022, 1:50 pm	#1
Nanozeugma Heptode Join Date: Nov 2017 Location: London, UK. Bury, Lancashire quite regularly :) Posts: 611	Cutting accurate holes in thin plastic sheet. Hi all, I'm in the process of attempting to fashion a replacement drum cover, bearing station names, to replace a damaged original for a Murphy A48. Thanks to the kind efforts of Jerry (cathoderay57) I now have an accurate reproduction (template) of the station names. I haven't yet decided whether to use clear PETG sheet with clear self adhesive printed film on the back, or just use OHP film. Now the problem. Having marked the hole centres, four per side, where the cover is attached to the metal support frame, I'm struggling working out how to punch the holes accurately (in the right place.) I have a rotary punch which goes up to 4.5mm, and a standalone 5mm steel punch. The issue is that I cannot see what I'm doing, trying to align the punch over the proposed hole centres, marked on the material with an indelible marker dot. I wonder if there is a simple answer to punching the hole(s) in the right place that I may have overlooked? __________________ Thermionic Emission, warms the cockles of your tubes.