Does any know how TPU tubes are made and especially how they are fused or joined for example around the valve? I ask because I have seen them fuse the hot edges of the butyl tubes into their round shape and then bake them. However, I cannot find details or videos on the manufacturing of TPU tubes. I know they are injection moulded, but nothing more.
I ask to discern if making custom-size tubes are possible especially since some sizes aren’t available. I have seen one made for the 36"ers, but they are not readily available online. Not taking into account the price and problems I would have shipping it here.
I know patch kits are available by now, but don’t expect it to hold for the patching of 2 tubes to each other. Unless you differ in opinion.
If anyone has insights it would be appreciated.
Not directly related to your question, but have you tried sending an email to 36Polici? Luca seemed really helpful and he may arrange something to send you a pair of TPU tubes 
I have now had my own TPU hoses manufactured and have good business relationships with a manufacturer. I’m currently having 20x 4.0 and 24x 4.0 Fatty tubes with AV valves made. Of course I could ask if he would also make a 36" for me.
Would there be interest? Should I ask my manufacturer if this is possible? But I would have to do it now because I currently have an order open. It wouldn’t be worth it to only have a 36" made just because of the shipping costs.
But my tubes have AV valves and a 30mm valve length. I don’t know how many of you have rims with an 8.5mm bore (AV) and how many with 6.5mm (FV), as I haven’t had a 36" in my hand for a long time. If I can remember, QU-AX, QX, Kris Holm, Nimbus tubes with AV valves, correct?
Thanks for all the offers, but I am just interested in understanding for now. I don’t currently have a need, but I keep wondering in the back of my mind for certain projects, so thought I might as well ask.
Luca is very kind and he sent a 36" kit to Montreal, Qc quick and cheap