These pcm collets hold taps and are sprung loaded, they are available in the whole range of er sizes.

You can buy them from wnt but they are quite pricey, I found a few er25 on ebay that I use on my Denford triac. If you buy the largest diameter you can find you can make sleeves to hold smaller taps.

https://www.pcm.ch/en/products/tapping-collets