You might try at: https://groups.io/g/MicBuilders
Either that or companies that make electrostatic speakers.
Either that or companies that make electrostatic speakers.
Kite and model plane builders may have thin mylar. They did when I needed it some years ago.
Edit: https://www.freeflightsupplies.net/index.php/products/lightweight-covering-materials
Edit: https://www.freeflightsupplies.net/index.php/products/lightweight-covering-materials
Spoke with rep at HiFi polyester films, UK - thinnest film is 12um.
also:
Awaiting mail from Goodfellow advanced materials, UK.
Requesting 20m x 1m of 2, 4 & 6um uncoated DuPont Mylar.
I'll post outcome.
also:
Awaiting mail from Goodfellow advanced materials, UK.
Requesting 20m x 1m of 2, 4 & 6um uncoated DuPont Mylar.
I'll post outcome.
This firm has 5000 x 315mm lengths in 1um, 2um, 5um, 7.5um 10um & 12.5um at £5 per length + post.
Job done, thank you.
Freeflightsupplies (UK) have 2um & 10um in clear ( not aluminised ) - currently out of 5um & 7.5um.
I used to ship 6 micron Mylar but the exceptional width of 100 cm combined with low DIY activity forced me to stop doing this. If people live close in my area (Netherlands) theycan pick.it up.
Google for RC models or model planes with mylar and the thickness needed, I'm sure you'll find something
https://the-mt-shop.co.uk/product_i...ucts_id=584&osCsid=6v303jgqotg23m4df1flakml06
https://the-mt-shop.co.uk/product_i...ucts_id=584&osCsid=6v303jgqotg23m4df1flakml06
We have 3, 4, 6 and 8 micron in stock.
3 micron is 650 mm wide
4,2 micron is 670 mm wide
6 micron is available in 500 and 650 mm wide
8 micron is 520 mm wide
All pre-cut on 20 meter length rolls.
https://quadesl.nl/winkel/onderdelen/origineel-dupont-mylar/
There is very little market for thicker Mylar,, so we will probably not re-stock that. Bulk sales is 3 and 6 micron.
3 micron is 650 mm wide
4,2 micron is 670 mm wide
6 micron is available in 500 and 650 mm wide
8 micron is 520 mm wide
All pre-cut on 20 meter length rolls.
https://quadesl.nl/winkel/onderdelen/origineel-dupont-mylar/
There is very little market for thicker Mylar,, so we will probably not re-stock that. Bulk sales is 3 and 6 micron.
I now have 10m each of 2, 7.5 & 10um clear Mylar.
Stocking up with 3 & 6um, as above, will see me through.
Taking baby steps to make vanilla planar mid / high units to be used with a 110mm scanspeak dipoles for low end support. A small & modest unit aimed at mid band clarity.
Speccing cables for stators now,
annealed 0.5mm solid copper, pvc, ho5v-u looks good to go.
Attaching & tensioning, painlessly, repeatedly and slickly may take some time🙂
Thanks for everyones help, I've everything I need now.
Stocking up with 3 & 6um, as above, will see me through.
Taking baby steps to make vanilla planar mid / high units to be used with a 110mm scanspeak dipoles for low end support. A small & modest unit aimed at mid band clarity.
Speccing cables for stators now,
annealed 0.5mm solid copper, pvc, ho5v-u looks good to go.
Attaching & tensioning, painlessly, repeatedly and slickly may take some time🙂
Thanks for everyones help, I've everything I need now.
I don't know what sort of speakers you are building, but if you need to tension the mylar film, I have a tensioner design that I just used to successfully restore a pair of Quad ESL-63s. It's a variation of a tensioner I developed in the 80s when I started building ESLs. The tensioner allows on the fly tuning of the resonance of the film before gluing to a frame. It's an MDF/wood rectangle with a bicycle tire tube stretcher over it. There is double stick tape on the underside. You lay the film on it, and stick it to the tape on the underside, then inflate the tube which tensions the film and eliminates wrinkles.
tensioner with film and glue
I test resonance by bouncing a ball bearing against the film and capturing the sound with a UMIK-1 mic. The mic plugs into a laptop running REW. The RTA in REW provides the spectrum of the sound made by the ball bouncing on the film. You can adjust the resonance by tweaking the air pressure in the tube.
tensioner tilted up for resonance testing
Here's a typical resonance plot for a new diaphragm on a Quad driver:
underside of the stretcher with film attached
I tested factory diaphragms before replacing them (the stators under them had come unglued and the only good way to reglue them was to destroy the diaphragms), and set the resonance of the new diaphragms slightly higher in primary resonance. When you get the resonance you want, apply glue (3M 4693H) to the film and the frame, wait 20 minutes for the glue to set, then put the frame down on the film.
4693H is contact cement formulated to bond to low surface energy plastics like polyester. It forms a strong bond with the film and doesn't creep due to the film tension. I have some drivers I worked on around 2005 and they are still bonded. Here is an example of the bond:
If you're making electrostatic speakers, Licron Crystal antistatic coating on the film gives 10^8-10^9 Ohms/square. Those 2005 drivers (with Licron, before Licron Crystal was available) still read 10^8-10^9. It takes only seconds to apply and it bonds with the polyester.
tensioner with film and glue
I test resonance by bouncing a ball bearing against the film and capturing the sound with a UMIK-1 mic. The mic plugs into a laptop running REW. The RTA in REW provides the spectrum of the sound made by the ball bouncing on the film. You can adjust the resonance by tweaking the air pressure in the tube.
tensioner tilted up for resonance testing
Here's a typical resonance plot for a new diaphragm on a Quad driver:
underside of the stretcher with film attached
I tested factory diaphragms before replacing them (the stators under them had come unglued and the only good way to reglue them was to destroy the diaphragms), and set the resonance of the new diaphragms slightly higher in primary resonance. When you get the resonance you want, apply glue (3M 4693H) to the film and the frame, wait 20 minutes for the glue to set, then put the frame down on the film.
4693H is contact cement formulated to bond to low surface energy plastics like polyester. It forms a strong bond with the film and doesn't creep due to the film tension. I have some drivers I worked on around 2005 and they are still bonded. Here is an example of the bond:
If you're making electrostatic speakers, Licron Crystal antistatic coating on the film gives 10^8-10^9 Ohms/square. Those 2005 drivers (with Licron, before Licron Crystal was available) still read 10^8-10^9. It takes only seconds to apply and it bonds with the polyester.
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The methods and materials you mention are those I will use; I appropriated them from a previous post of yours 🙂
Thank you.
Thank you.