Cutting a cot mattress to size

[Sweetandawfulsour]

Bought a gorgeous extendable vintage cot, didn’t think about mattresses until now. Struggling to find anything to fit, either too narrow, too wide or too long! Bought one on a whim and it’s just a smidge too narrow, leaving a 6cm gap.
Looked at having a mattress made to measure but seems quite expensive.
Has anyone had the same issue and cut a memory foam mattress to size? Or built up around the existing mattress to fill the gaps?

babymattressesonline.co.uk

Hi that would be unsafe to do as it wouldnt be regulated and upto the current safety standards . The cot sounds too old to use unfortunately
I highly recomend safe sleep and baby care evidence based group on Facebook if you have an account. Good luck