Refurbing rstt's

[kelk11]

I'm currently up to the stage of spraying, having given the alloys 2 light coats of primer i'm now at this stage

However between one of the spokes i've got this

first question, what has caused this?

and secondly can i just sand it smooth and carry on layering the primer up?

Thanks

 

[Oke Phill]

I hand this on a caliper i was spraying, and i just rubbed it back sprayed over it, and even now it appears to be ok.

Thats what i would do any way.