Hi guys,

quite a while ago I came across the MTI hose, developed in Germany. A regular spiral tube (albeit a larger diameter) covered in an air-permeable membrane that is impervious to resins.

Question is, are any of you familiar with this product? They promise cosmetic, pinhole-free surface, without the need for catchpot and continuous vacuum. Was just curious if easycomposites or some of the other pros out there have any experience and if its worth giving a try, looks interesting.

Cheers

Hello,

the MTI hose is our product. I like the discussion here, that shows me people think about things and do not just believe in what is told them.
The thing with the oversaturation can be correct if you let your resin feed line open.
But you will get really fast a feeling for that. You can also place your resin feed about 1-1.5 meter below your part. This height difference will create a presure difference that will prevent a oversaturation. We have a study here wherethey produced pinhole and void free part by MTI hose with a VF between 62 and 67%
The reason why we did not make a hose with slightly bigger poores is that than the physical advantage of the hose will be gone.
Now you have a closed system after infusion where no vacuum is working, but the full ambient pressure will compact the laminate. If the poores will be a little bigger, the vacuum can still pull resin out and so air inside the part can cause micro voids, pinholes or other mistakes.
I added the video of how it works, I hope it helps to understand the advantages.



Dominik