Does vinegar make conkers hard?

Online Answer
Try slow baking the conker first and then coat the outside of the conker with hand cream to make the conker shell more flexible to the impacts. Pickling conkers in vinegar is said to make them rock hard.
Related Questions 📌
A conker is the seed of the horse chestnut tree (not the sweet chestnut tree where we get edible chestnuts from). It is a hard brown nut which is found in a prickly casing. The green outer casing of the seed will turn brown and crack open revealing the conkers inside..
The story goes that conkers contain a noxious chemical that repels spiders but no-one's ever been able to scientifically prove it. There's hearsay that if a spider gets close to a conker it will curl its legs up and die within one day. Others say spiders will happily crawl over conkers with no ill effects at all.
No. Conkers contain a poisonous chemical called aesculin. Eating a conker is unlikely to be fatal, but it may make you ill.

Clinical signs are usually seen between one and six hours after ingestion, although they can be delayed for up to two days.

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When are conkers ready to pick? Conker season is thought to start around August, and lasting through September and October, however, this can be affected by the climate and environmental factors. Conkers are ready when they have fallen from the tree as this is when they've hardened and ripened in the middle.