How to Refelt ZX Microdrive Cartridges

(Article and pictures by Will Woodvine)

It’s highly recommended that you re-felt ZX Microdrive cartridges before use. The reason for this is that the sponge/felt that sits behind the tape is VERY fragile. It often disintegrates when used these days and can cause the cartridge to jam up if the bits of old sponge get inside the cartridge. If this happens nothing can be done – the cartridge is dead. If the sponge/felt in the cartridge has gone it’s a very good idea not to use it. This is because the read head of the Microdrive won’t make good contact with the tape and the metal spring will rub on the tape passing over it – not a good situation!

Tools for the job

You’ll need sticky backed felt, tweezers, a scrapey thing, rule, knife and cotton buds. You’ll also need isopropyl alcohol. The felt is the hardest thing to source. You don’t want anything too “hairy mary” – definitely something a bit more trim. An example of a source of suitable felt is here.

Removing the Debris

Here we can see the old sponge, you need better access so using clean tweezers lift the tape gently.

This gives better access and allows you to gently scrape the sponge. When doing so make sure no debris falls into the cartridge.


Cleaning Up and Preparation

Now using a cotton bud dipped in isopropyl alchohol, clean the surface of the spring. It’s a good idea to tilt the cartridge at an angle such that there’s no risk of debris or isopropyl alcohol falling into the cartridge itself.

Now cut the felt to size roughly the same size as the metal pad.



Remove the paper covering the sticky on the back of the felt, and using the tweezers place onto the spring and firm down.


Now it’s time to take up the slack in the tape. Using the handle of the ear bud, gently apply pressure to the tape and roller on the side and roll down. Repeat this until the slack is gone.


Time to test the cartridge – what treasure from the past will we find?


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