I am going to place an order for ePTFE membranes, likely from this company on Alibaba.
Before I email them to get quote in the next couple of days, is there anyone who wants to join this order? I am based in Greece. I will post your part of the order as soon I receive the membranes.
I am likely going to order about 100-200 for myself. I would prefer the black color, but I am ok with switching to white if color is important for other people.
I am also willing to consider other membranes instead of the one mentioned above, if you have good reason to believe they would perform better.
By the way, I am thinking of placing the membrane on the inside surface of the box, and a single layer of 500-mesh woven on the outer side (https://www.inoxia.co.uk/products/mesh/sheets/500-mesh?fbclid=IwAR2HPEDe7WNJ_FHsB8Oh0-7IjJNBM5vUskUnQVJXbaStMNlbyK8to3hvAEc / instead of the 2-layer NicWax treated suggestion mentioned in another post - here ). Would the combination pose a problem? I am recording at 8KHz sampling rate only. I was thinking that the wire mesh would keep insects away (which have poked a hole in one of the two AudioMoths I have tried - see photo below), while also limiting the amount of water that would linger on the lip of the drilled hole - if I had only the membrane on the inside. Any thoughts?
Looking forward to hearing from interested people.
Sadly not yet. Parts have been delayed (battery packs I wanted to connect to the AM), so I have not gotten to this point. : (
Did you try fixing the ePTFE membranes to the inside of the sound hole and the 500-mesh on the outside, and did that work well?
I am afraid I have ordered them already (just 50 samples in the end), and they have arrived. I have not put them to use yet, as I am waiting for the boxes etc.
They look quite different from the one in the photo above - look thicker/more robust. The white one you see in the photo of mine was provided from Andy to test. I have not looked into how the new ones compare with the old ones either.
The product I have ordered is this:
The total cost, incl. shipping to Greece, was 35 USD. The cost of the membranes was 0.20/membrane for up to 50 samples (limit) which adds up to 10 USD. The remaining is the postage fee. It arrived quite quickly.