I've recently been printing using NinjaFlex (which is brilliant BTW). On angled thin walled prints, the Replicator 2 output cooling fan would sometimes push the filament to the right causing it miss the layer below.

I wanted to remedy this by having the air come from both sides.

My previous version of the fan duct suffered on some machines by being too low and as it was supported on one side, would hang down on the right.

I realised that I could support the duct by clipping it on both sides of the carriage.

I started out by making something that would clip on, then I attached it to the fan and then added the air ducts. The first attempt enclosed the heating element too much and was too low.

After printing for about three hours, a PLA version of the final design started to soften in the middle which meant that the clips at the sides became loose.

I reprinted it in T-Glass and for good measure, I applied some copper tape to dissipate some of the heat.

The one photographed (blue) has printed continuously for 10 hours at 250 degrees (Nylon) and shows no signs of melting. It was cool to the touch when I removed it after the print.

I have marked this as work-in-progress as I have only used it for a few days and it may need adjusting.

Some air flow analysis would certainly help, but I'm afraid I don't have any such tools :( so I'll have to settle for the empirical approach... Unless you can help?

Update
I found the airflow from the small holes was too powerful, I've produced a version with wider holes that is more gentle whilst still providing air from 3 sides.

Another Update!
Fisk4 asked if I could widen it for the people who've bought the Aluminium upgrade, apparently the body is 1.5 mm wider. So I've uploaded a version for that. Don't use this unless you have the Aluminium upgrade