Coating to preserve foam surrounds?

[head_unit]

I'm visiting my mom, enjoying some speakers I built her long ago whilst in diapers 😛. They still sound nice! The one Achilles Heel is the woofers have foam surrounds-still intact but looks like starting to flake a bit.

What product(s) are good to coat on that to help prolong the life?

P.S. The woofers were custom built by me, custom pole pieces and cones and I wound the voice coils etc etc., no way to get a replacement surround and no need either. For her listening, I'm not worried about the small change in response that will result, these old beasts have fairly crude crossovers since simulation tools were not developed yet. And the listening is all off-axis throughout the house.

 

[stled]

liquid latex rubber is what I use. It can be found at most hobby shops. You can thin it using normal household ammonia (its the solvent used for latex)
I usually apply it using a very small paint brush.


Stled