DiY Polyurethane Foam seat

[Lavabo]

Im looking at a way to make my own seat  with spray foam insulation (polyurethan)

The hard part is making the mould on top of the EUC

i guess i could use cardboard taped to the wheel with a plastic covering the inside part, then i spay the foam !!!

just an experimentation...

Hope  i will not get this:

 

Edited December 13, 2019 by Lavabo

[mrelwood]

I was considering doing the same some time ago, and I would’ve covered the wheel with saran wrap, and then made cardboard walls as a mould.

My testing with the foam turned me off though. The air cavities in the spray foam are too big for a seat, and the material doesn’t bounce back like PU insoles do for example. Spraying the foam in a cup first then stirring with a stick gets rid of the large bubbles, but the result might be a bit on the dense side. Then again, bicycle seats are usually very dense as well.

I just received a big bum bicycle seat, and the spring metal brackets will hopefully arrive soon as well. 30€ in total, 20€ if you want to use a single bracket.

Edited December 13, 2019 by mrelwood

[WIZARD]

https://photos.app.goo.gl/irDGq9g4HtHJGrdR6

[Aneta]

On 12/13/2019 at 6:36 AM, Lavabo said:

Im looking at a way to make my own seat  with spray foam insulation (polyurethan)

How is the resilience of the foam insulation? I thought once you compress it, it stays in compressed state.

High-resilience foam typically used in auto seats, couches, mattresses, etc. doesn't have this issue and can easily be cut with hot piano wire (heated by current). You can also buy "hot knives" and similar tools for cutting finer pieces where it needs to match the shape of the wheel.