I have a case that has filter fabric lining the doors of my case (my the sides of my case are basically giant open grills hence the filter fabric. So when I close the case the ends of the copper pipes (which extend about a cm beyond the alluminum fins of my heatsink are touching the fabric. Is there any danger caused by this? I could:
A. Remove the fabric which leaves just the metal of the door (They might still touch the metal door slightly..
As long as they are only just "touching", you don't need to worry.
If any pressure at all is being put on them, then I would be concerned.
I would rather have them touching the fabric than the metal door, that is for sure.