Post by Arke on Aug 25, 2022 14:21:34 GMT
The Arke 1 is now named the Arke Duo (thanks for the suggestion Oli).
A few weeks ago (before the Arke Duo build) I had interest in a curved cheek design, something similar to the curved 'wing' profile on my Ekta floorstanders. I needed a reliable and reasonably efficient method of achieving a consistent curved profile. I didn't fancy belt sanding loads of material again (it's not easily repeatable), and CNC would be too expensive for an initial few pairs of speakers. If the demo speakers are well received, CNC can be investigated further.
How do I build four idential and repeatable wing profile cheeks? After some thought, I decided to build up a wing profile with a lamination of angled strips. This would require a series of very accurate cuts on the table saw. The demo pair would use 16 strips of 24mm birch ply - actually 23.4mm after 'seasoning' - it is never fully dry from a timber merchant. These 16 layers would be cut as shown below:
(The radius on the front edge was later changed to a bevel)
The table saw blade was set and checked with a digital angle measure - I could set to 0.1 degree accuracy.
There would be 64 strips in total, each cheek a lamination of 16 pieces:
It was very fiddly to lay up for bonding, but pretty straight forward once I had a good method:
These cheeks received a 45 degree bevel to the front edge and a 45 bevel to the top, along the curve. The top angle was ideally cut with the wing vertical on the table saw - a jig was made to achive an exact cut in this orientation:
Additionally, the cheeks received a 1mm recess around the edges - this would create a shadow gap between the central cabinet and the cheeks.
Once complete, the cheeks were bonded on and constrained a 2mm layer of Silent Coat. I will investigate other damping materials in due course.
A few weeks ago (before the Arke Duo build) I had interest in a curved cheek design, something similar to the curved 'wing' profile on my Ekta floorstanders. I needed a reliable and reasonably efficient method of achieving a consistent curved profile. I didn't fancy belt sanding loads of material again (it's not easily repeatable), and CNC would be too expensive for an initial few pairs of speakers. If the demo speakers are well received, CNC can be investigated further.
How do I build four idential and repeatable wing profile cheeks? After some thought, I decided to build up a wing profile with a lamination of angled strips. This would require a series of very accurate cuts on the table saw. The demo pair would use 16 strips of 24mm birch ply - actually 23.4mm after 'seasoning' - it is never fully dry from a timber merchant. These 16 layers would be cut as shown below:
(The radius on the front edge was later changed to a bevel)
The table saw blade was set and checked with a digital angle measure - I could set to 0.1 degree accuracy.
There would be 64 strips in total, each cheek a lamination of 16 pieces:
It was very fiddly to lay up for bonding, but pretty straight forward once I had a good method:
These cheeks received a 45 degree bevel to the front edge and a 45 bevel to the top, along the curve. The top angle was ideally cut with the wing vertical on the table saw - a jig was made to achive an exact cut in this orientation:
Additionally, the cheeks received a 1mm recess around the edges - this would create a shadow gap between the central cabinet and the cheeks.
Once complete, the cheeks were bonded on and constrained a 2mm layer of Silent Coat. I will investigate other damping materials in due course.
