Hey fellow woodworkers! I'm a bit of a stubborn student with a project that involves bending a piece of 12mm plywood into a cylinder. The calculators I found online only seem to cater to 180-degree bends, but I'm hoping to use a single piece of plywood. My plan is to make 26 evenly spaced cuts, each about 195mm apart. I did notice that with the 180-degree curve, the spacing wasn't even, which makes me think it's all about distributing the pressure evenly. The plywood I'm working with is 528mm wide. I don't get to use the woodworking machines very often, so I'd really appreciate any advice before I dive in. Math isn't my strong suit either, so I'm a bit worried I might be overthinking this! Thanks for any help you can provide!
3 Answers
I suggest you don't go down that road. Instead, try building a form for the shape you want, and use a few sheets of 3mm bending plywood to laminate them together. Make sure to offset the seams as this technique will yield a much better finish.
Thanks for the suggestion! However, this project has a solid requirement for the 12mm plywood. Is the concern with stability and difficulty still relevant?
Honestly, I'm skeptical about your approach. If I were tackling this, I'd try spacing the cuts evenly around the cylinder. From what I got, your 528mm ply gives a diameter of about 168mm. The inner diameter would then be around 144mm, leading to an inner circumference of roughly 452.6mm. So you'd need around 25 kerfs, which comes to a spacing of about 21mm between each cut. This isn't too far off from your initial plan. Just be prepared for the possibility that you'll need an extra kerf or two to help it bend nicely. Oh, and don’t forget to use a form and clamps for the best results!
Thanks for the detailed breakdown! I'm relieved to see my math isn't too far off either. I'm just wondering though, why do you think I might end up disappointed with the results?
Trust me, you're setting yourself up for a struggle. If you have to use the 12mm plywood, consider laminating it with a bending plywood method, and veneer it later for a smooth finish if you want a nice look.
I appreciate the advice! Just wanted to clarify, I'm stuck using the 12mm as is for this project. Is that just too tricky or fundamentally impossible to make it work?
I had to convert to inches, but your 3mm plywood sounds just right for strong bends. I’m curious though, would a standalone 3mm sheet hold the cylinder shape on its own? The circumference seems a bit under 2 feet, right?