alpha in zbrush pulling towards centre

MattHatter

So im modelling a low poly sword and i want to have glyphs on the side. to do this i made an alpha to apply to a brush. when i use it the alpha works fine except for the fact the walls of the impression, instead of being straight into the model, all seem to pull towards the centre of the glyphs.
does anyone have any idea how to stop it from doing this? 

hexflow

Did you set your focal shift to -100 before applying?

MattHatter

yes set it to -100 but it still warps as if the walls are being pulled to centre

Treece

Personally I would use the alpha as a mask instead of applying it to a brush.  Then invert mask and inflat or use transpose line to indent it.