The physics

Oxidation and dust

On this page11

Strings oxidise And a fingerprint starts it So spare strings want a sealed container Coiled strings tangle and kink Rosin is brittle and dusty The dust is the product escaping Which is why the traditional container is a tin A small jar is the substitute Mouthpieces chip None of which this shelf is purpose-made for References

The oil from a hand is what starts a string.

Strings oxidise

Wound metal strings corrode, and the corrosion changes the mass distribution along the string, which changes the intonation before it changes the tone.

And a fingerprint starts it

Skin oil and salt on a steel or bronze winding is the initiator. Which is why a spare set handled and put back loose lasts less well than one left sealed.

So spare strings want a sealed container

The sealed sleeve they are sold in is the right object and it gets opened and discarded. 11 liners and sealing discs here, for a jar used as a replacement.

Coiled strings tangle and kink

Which is the other failure. A kinked wound string is finished, and loose strings in a jar find each other.

Rosin is brittle and dusty

A cake of rosin is pine resin, hard and glassy. It chips, it cracks when dropped, and it sheds powder every time it is used.

The dust is the product escaping

A rosin cake stored loose in a case coats the case, the bow and the instrument in powder. It is cosmetic on the case and it is not on a varnished top.

Which is why the traditional container is a tin

A small screw or slip-lid tin, deep enough to hold the cake and the dust it sheds. This shelf has no tins and no steel at all.

A small jar is the substitute

And a reasonable one: 110 PET single wall jars and 26 PP single wall jars. Glass is a bad idea for a container that lives in an instrument case.

Mouthpieces chip

A precision surface, usually ebonite or metal, and the tip rail is the part that matters and the part that breaks. Padded separation rather than a sealed environment.

None of which this shelf is purpose-made for

Which is the honest position: good general containers for a craft whose specialist products come from music suppliers, and genuinely useful at the bulk and bench end.

References

No federal regulation governs reed storage, rosin storage, string storage or mouthpiece storage as such. This property states that rather than borrowing an authority from a neighbouring craft, and the content for those four leaves is material behaviour and measured catalog facts rather than quoted law.

The Davis Pack Supply catalog, measured 19 October 2026. The instrument care shelf is 1,026 rows: 525 containers and 501 closures. 5 mL to 500 mL with a median of 118; 30 containers at 15 mL or under, 100 at 30 or under, 207 at 60 or under, 390 at 120 or under. 266 PET, 119 glass, 78 PP, 62 HDPE, and no steel or tins at all. 287 bottles, 224 jars, 12 tubs and pails, 2 tubes. 147 clear, 112 white, 82 amber, 51 blue, 45 natural, 37 black. Closures: 345 continuous thread, 43 dropper assemblies, 27 dome lids, 19 lug and twist, 16 flip top, 14 phenolic, 11 liners and sealing discs, 6 dropper tips and caps, 6 round tubs. Necks: 96 at 20-410, 59 at 24-410, 56 at 89-400, 56 at 70-400.

Written from 21 CFR 172.878 and from the catalog as it stood on 19 October 2026. Nothing here says a food-contact regulation applies to an instrument lubricant; 172.878 is cited as the published specification for white mineral oil, which is the benchmark a manufacturer can either meet or not. The other four leaves have no governing regulation and this property says so rather than borrowing one.