bendy plywood + glass matt + resin. The above acts as form tool too.
Roughly speaking...
Roughly speaking...
I do wonder though… with know-how of, and access to, such manufacturing technologies, why bother with wood at all, especially as good quality ply has become quite expensive.
Earl Geddes used PU (sheets and cast), Magico uses reinforced carbon fibre plus CNC’ed aluminium baffles in their M-series, and YG simply makes everything out of aluminium for their higher end speakers. I haven’t heard Earl Geddes’ speakers, but the other two makers achieved a clarity in sound I have never heard from any speaker with a wood cabinet.
Earl Geddes used PU (sheets and cast), Magico uses reinforced carbon fibre plus CNC’ed aluminium baffles in their M-series, and YG simply makes everything out of aluminium for their higher end speakers. I haven’t heard Earl Geddes’ speakers, but the other two makers achieved a clarity in sound I have never heard from any speaker with a wood cabinet.
Good quality plywood is still cheaper than all those other materials.
Gelcoat, glass matt, 1L resin. The 4mm thick baffle worked out at £70 plus an hour. I then bond in a machined 15mm ply in the back. It’s really quite a stiff inert baffle at that point.
In between the bendy ply i intend to add a glass matt. It will be a stiff curved cabinet.
Designing the way I have allows me to rest the cabinet on it side, throw in some chop strand glass and pour in a casting resin. Quite a few low shrinkage fast cast resins around now.
I guess the ultimate would be to use FEA and alter design to minimise resonances.
In between the bendy ply i intend to add a glass matt. It will be a stiff curved cabinet.
Designing the way I have allows me to rest the cabinet on it side, throw in some chop strand glass and pour in a casting resin. Quite a few low shrinkage fast cast resins around now.
I guess the ultimate would be to use FEA and alter design to minimise resonances.
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Maybe it is in Canada. My local supplier has been out of stock for yonks a d even before that could only supply Russian grade birch ply. The only high grade retail supplier I know of in my region wants nearly £300 for a 24mm sheet…
Yes if CLD is used to also dampen down the resonances. But that must require a lot of build/measure/repeat to find a way to achieve the desired damping. The damping material is not some off the shelf stuff so composition and thickness will be experimental.
For mass-loading the cabinet? Lead sheets are still available in the UK from roofing stores. For CLD, Earl Geddes mentioned PU+glass beads. Is your resin hard or flexible?
Internal structure will be black valchromat. Designed it to slot together easily.
With a bendy plywood outer with a veneer.
With a bendy plywood outer with a veneer.
Sorry for the slow progress reporting!
The cabs are coming along.
4 layers of 5mm ply + 400g matt in between each layer. I’m going to use stainless steel powder in the intermediate layers to add some mass. Also, the polyester resin should infuse into the bendy ply to create an interesting plastic/wood composite in those layers.
All finished with 1mm wood veneer.
The new design front GRP baffles are almost done. Will update next week with those.
The cabs are coming along.
4 layers of 5mm ply + 400g matt in between each layer. I’m going to use stainless steel powder in the intermediate layers to add some mass. Also, the polyester resin should infuse into the bendy ply to create an interesting plastic/wood composite in those layers.
All finished with 1mm wood veneer.
The new design front GRP baffles are almost done. Will update next week with those.
I still have a pair of Beovox CX 100 and a few Meridian DSP33 as surrounds. Both use cast or extrusion alloys for the bulk of the cabinet.
I’ve been using resin boards from Sikka and Trelleborg for 25 years in my day job. I have no hesitation to try anything. Part of me enjoys working with wood too though. Sadly I’m super busy so finishing hobby projects is super long process.
v3 underway
gell coat down first
1 layer of tissue and 2 layers of glass
then bond the "cabinet" into this with 10 min cure low shrink resin
then finish with external veneers
sand and polish
gell coat down first
1 layer of tissue and 2 layers of glass
then bond the "cabinet" into this with 10 min cure low shrink resin
then finish with external veneers
sand and polish
Somewhat convoluted way to make a baffle. Apologies to any engineers watching.
