Recently we asked for some advise on our social media pages on the best method/equipment on cutting sheets of 4mm polycarbonate sheets, to reglaze a greenhouse
We were told it was best to use a hacksaw, a fine bladed jigsaw, a normal "StanleyBlade" style knife and one individual suggested we contacted Jewelblade Ltd as they had a variety of blades and cutting equipment.
Having contacted Jewelblade for guidance, they provided us with a box of 100 blades and a Delphin 03 craft knife.
Upon viewing these craft knife we were surprised that the blades were not retractable, meaning you had to either leave the blade out or dismantle the knife. On a positive note, the craft knife came in a sheath that connects on to a belt, so means it is always to hand and not left lying around with an exposed blade. Additionally, as there was no release button like a convention retractable blade knife, greater pressure could be used when cutting a tough bit
Blade replacement did not require a visit to the toolbox for a screw driver as the Delphin was dismantled by rotating a wheel.
100 blades suggested that we would go through loads every sheet of polycarbonate and we had a lot to cut. We needed over forty separate pieces, of varying shapes and sizes, that was an awful lot of cutting. Amazingly we still have 70+ blades left. Each blade was capable of cleanly cutting across the grain and when they blunted they were still capable of cutting with the grain
We tried other methods including a hand hacksaw, a standard "Stanley" style knife, an electric jigsaw, none of which was particularly successful - the stanley knife being the best of these. This was particularly the case when trimming fine slivers off pieces that were slightly too large.
All in all we would highly recommend the Jewelblade if you have a several sheets to cut, and is definitely worth the money (we found it online for £13.26 from axminster)