VDS and damping
Quotes are verbatim and attributed to their original authors.
A thin rubber strip — "VDS", short for vibration damping strip — sits between the steel edge and the fibreglass in most layups. Despite the name, the forum's settled view is that its real job is bonding and sealing, not damping.
What VDS actually does
The rubber lets the steel edge and the glass move relative to each other instead of cracking the epoxy bond, and it seals the edge against water:
One builder found skis built without it had rusted edges inside, while those with it did not — evidence the strip's value is sealing dry fibres from water at the edge.
Does it damp?
Mostly not, in any way you can feel. As bluntly put in the thread: "It is common knowledge that VDS is for bonding/sealing and has no dampening at all." A super-thin rubber sheet simply cannot absorb meaningful vibration — the name is marketing.
Real damping
Builders who chase genuine damping look elsewhere. Metal layers (aluminium, titanal) add it in racing skis but can delaminate under park impacts, and "adding metal to a ski doesn't always provide damping — but if it's used correctly with the right combination of materials, in the right spot, then you might be able to improve damping" (#2935). Cork layers and constrained-layer schemes (as used by big brands, often patented) also come up, and a denser, heavier core (e.g. all-ash) simply rides more damped than a light one.