What Screen mesh should i use for this??

[Appstro]

What Screen mesh should i use for this??
Its Gray ink on a white shirt. I was thinking 150??

[Denis Kolar]

230

I would go high, keeps the image clean.
I do not know what do you have from equipment, I mean exposure unit, but if you can expose fine halftones (fine lines), I would go as high as possible on white tees

[Appstro]

I am using a ryonet black light unit. 230? OK

[Denis Kolar]

150 would print OK too, you would just have a bit too much ink on the shirt.

Darker colors on a light shirt do not need much ink.

150-160-  OK
190-200- Better
230 - best, if you can expose it nicely

That is my way of looking at that, someone else might chime in too

[mimosatexas]

I would agree.  Depending on your gray, I would even go higher and p/f/p (if needed).  I have been using clear base with .5% black mixed in for tonal stuff recently, and it looks great on a white shirt.  I print it through 280 mesh, no p/f/p, with tons of pressure (manually) and it basically has no feel and very little dot gain.