I have one of those wooden toilet seats that every DIY store sells these days, and the plastic nuts which hold it in place have broken (as they always seem to after a while). In my previous house I managed to get some metal replacements from my local B&Q, but I can't find any now (not even online so far).
Does anyone have a suggestion where I might get some - or if not, what size nut I would need if I chose to use a large washer and a standard nut?
The most likely size is M6 which you should be able to get from any car spares shop, if these don't fit but look about the right size your seat may be so old that it has whitworth threads, again the car spares place may be able to supply you with some 1/4w nuts.
It may be that you are over tightening the plastic nuts if they break so quickly. You should fit them with a rubber washer and a plastic washer, rubber one to fit against the pan and the plastic one next to the securing nut as you will not be able to tighten the seat effectively otherwise. There is no need to overtighten the nuts if secured in this manner. Hope this helps.
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