Blank turret board (PTFE)
Modern, high-performance turret board material that’s super-easy to drill and cut
For me, one of the frustrations of using phenolic board material is that it’s just TOO darned hard to cut to size for yourself. And that makes it very difficult for customers to trim it to size to suit their own projects. Worse still, it’s hard to drill, and drill bits wear out prematurely. But with this PTFE (same material as Teflon) board material, the exact opposite is true: customers can cut it without special tools and drilling it for turrets is very easy.
PTFE also has far superior electrical properties over phenolic. In all, I have converted all of my amp building to PTFE. There’s one minor downside – it’s not a laminate, so it’s not as stiff as phenolic. The solution is simply to add an extra mount or two – I recommend that you make sure there is a mounting point every 150-200mm along the board length. Cutting it is easy – you can use a power tool, or even a box-cutter (Stanley) knife. Just score it at the point you want to break the material, turn it over and bend it back – it will snap along the line, leaving a clean edge. No nasty edges, no fibres and no waste.
Dimensions & info
The PTFE board is 3mm thick (suitable for the large turrets and screwmount turrets) and is available in several sizes:
- 105 x 50mm – the size I use for the N5X power supply
- 143 x 67mm – the size I use in the WF-55 amp kit
- 190 x 50mm – the size I use for the N5X main circuit
- 257 x 67mm – the original Marshall 18W board (and SE-5a, photo right)