A little more expensive than canj00digit's but a more traditional style reducer is here. BTW that was the first search result on both Google and Ebay for "29mm to 18mm glass adapter"
This one is cheaper though- *Edit: posted above me now I see. But this post is here now. So deal with it.
Ahhh, that's much better!
I am going to get a couple soon for something I am doing and I couldn't find any lo-pro versions.
The added height of the non-lopros was annoying as hell.
Thanks for the link!
Yeah, I'm international too. After doing the math on the regular vs. the lo-pro adapters I think I can deal with the added height. It would cost me more than 4x as much for the lo-pros.
I've pinged a few UK glass blowers to see if they can help, will feedback the replies, in the meantime if anyone knows where these can be sourced in UK/Euroland.
Would need two pieces(in/out): male-->male & female-->female.
I would try searching scientific supply stores or scientific glass suppliers before a blower. Most blowers buy their joints from suppliers unless they make a hand ground joint. Best case you are paying mark up for a blower to order it for you, worst case you are paying them to make you a custom hand ground adapter which will be expensive. The one advantage a blower would have is they already have a scientific joint supplier so it would be easier for them to find it. I personally would put in the leg work looking for one myself and only contact a blower after scouring all the scientific supply vendors I could find.