Flexible Bellows Material for A/C Duct

[Hemi8]

I am installing a Vintage Air trunk A/C system and I need a solution to this hard plastic intake duct. Its a rectangular duct about 14" x 3", I need cut out a 3" section and attach some type flexible bellows to so I can position the evaporator properly. What can I use? Maybe some type of home A/C duct flex joint?

The rectangular hard plastic air return duct can be seen here:

http://www.vintageair.com/Instructions2013/905000-VUY.pdf

Mike

[HarleyR]

You need the hose pictured In illustration #2? I have access to 3 inch silicone hose.. Used for brake ducts.... Bends without kinking....

[Hemi8]

Actually no, there is a long rectangular hard plastic piece thats the air return, it fits in the rear package tray and goes straight down into the evaporator. Right now the trunk rods(G-body) are scraping it and also preventing me from mounting the evaporator because I need to pull it back towards the rear of the car. There is no flexibility to allow me to come back a couple inches so I need a flexible section, I've seen home A/C duct work with flex joints but I have no experience making one.

Mike

Mike