Steering rack gaiter

I am finding it difficult to get the correct steering rack gaiter for my car so i thought about making one in TPU. Its not quite there yet but I have produced a near perfect one using the thick walled file. The thin walled file may work as a single layer/spiral vase print but I am still working on that. I am a noob at Solidworks so it is far from perfect but it looks reasonable. The topmost bellow surface tends to still be porous which is a combination of not being able to hold it still and also possibly being a bit too thin.

I haven't tried it on a car yet but it is very strong and will stretch to about twice the printed length. It could do with a softer flex than 95 shore but then supporting it would be more difficult

Update May 2018
Printing the gaiter as folded re-entrant designs avoids the problems of them getting floppy and i could print one large enough to fit the real application. The straight sided design works well but obviously isn't particularly stretchy. Bot