Onoff

https://www.plumbingsuperstore.co.uk/product/floplast-110mm-rainwater-reducer-110mm-x-68mm-sp96-p5820.html https://www.bes.co.uk/universal-rainwater-adaptor-25439/ I just searched "110 to 68mm adapter". I would try and use the same make if rigid plastic, not all "68mm" fittings are equal sort of thing. A rubber adaptor of another make will be more forgiving.

Isn't there a risk of encroaching on the 25, 50mm or whatever gap under the membrane doing that and thus comprising the air flow? (Don't get me wrong I love FM330).

3D print a black, snap on cover.

Aren't both pronouns a little assumptive? You know what these academics are like! "Their" would perhaps me more appropriate... 😉

Unfortunately the whole construction method has loads of non airtight "gaps", PIR against the timber, even timbers ostensibly butted up against each other. It all adds up.

Funnily enough I'm building one using the two motors off the two, 2-post lifts:

Exactly:

How much?

1/2" chain & sprockets. 18T for the small one, 36T for the big one.

Nah...convert to single phase, job's a good'un. Runs off a 13A plug. Done it twice now. 3rd one lined up.

I've a couple of lathe & plaster ceilings to take down. Need a respirator but don't want to pay 3M money. I've been recommended this "clone": https://www.aliexpress.com/item/1005005857155207.html However people are suggesting I then use genuine 3M filters in it. However I've also found these: https://www.amazon.co.uk/ANUNU-Cartridges-Respirator-Chemical-Compatible/dp/B0B68R61L8?ref_=dslp_ap_dp Thoughts? Cheers

Edible dormouse: https://www.glis-glis.co.uk/roast-glis-glis-and-apple/

Measure it and I'll 3D print one in TPU if you like.

Something like this:

Comes with age that...