Hi,
it was my impression, that surface tension of the coating fluid decrased when I used foam brushes wiping several times. With the first wipe there were still many streaks, becoming less with every wipe till a consistent fluid layer developed.
Plasma treatment of course is still a way preferable procedure, but so far the appliance of a suitable coating with a foam brush/sponge didn't let me down.
jauu
Calvin
it was my impression, that surface tension of the coating fluid decrased when I used foam brushes wiping several times. With the first wipe there were still many streaks, becoming less with every wipe till a consistent fluid layer developed.
Plasma treatment of course is still a way preferable procedure, but so far the appliance of a suitable coating with a foam brush/sponge didn't let me down.
jauu
Calvin
Some of the ingredients in MT Audios coating was from abroad and now hard to find. It was a journey, and the final results was very good. Some problems with foaming and bubbles when applied that had to be overcomed. There is many speakers still working with this coating.
Very likely you damaged the Mylar on a microscopic level.
Experimentally rubbing PET 20 to 30 times with melamine foam at a force between 10N ... 20N will macroscopically slightly blur the surface of the PET.
While coating, one and the same membrane aera may be wiped 2 to 3 times (max.). The applied force (measured!) is in an order between 0.1N ... 0.2N (max.).
So does the the Mylar really get microscopically damaged by using a melamine foam brush for coating? IMO, not very likely. But I think that we both agree that long term results are inherently a question of future outcome*. So for now, there might be no clear answer if there is a risk of damage when resorting to melamine foam applicators for coating, or if there isn't.
For other tastes of potential membrane surface modifications see:
https://www.diyaudio.com/community/threads/membrane-preparation-for-coating.388623/post-7080358
* In accordance to Monty Python's wyse and precise police officer's talk: "If there were fewer robbers, then there wouldn't be wo many. Numerically speaking"