Rotocast help

So I am rotocasting skulls and I randomly have these mini bubbles that form apparently and once I apply color I get these texture discrepancy. You can see where additional rotations remove some bubbles. I just don't understand why they are there to begin with. Anyone experience this before. I am using smooth on 65d in a rebound 25 silicone mold.

how many pulls have you taken from the mold? and humidity may play a role in the bubbling, although im not sure if it would cause bubbling to happen like that, and also on the outside of the cast. if you've had a lot of pulls from that mold though it may just b parts of the mold deteriorating

edit: honestly though, i cant tell how it looks in person with the problem, but it looks damn good as is, seems like it adds to the "age" of the skull!

not seeing the bubbles in the pic... as far as the color, tell me what color you are adding, how you are adding it and how much?

laxman09 I have done 5 pulls from this mold, its pretty new. Beaker, The pictures do make it hard to see but essentially if you look at the top of the skull in the center of the pic. You see that color difference that looks like a trapezoid. Those are the bubbles that I am assuming are happening in the first layer which causes the resin to cure with tiny pockets which grab more of the paint/stain and in turn cause those texture lines to form.

In terms of color, I am letting the skull fully cure then I am using wood stain as it gives a great aged look and grabs all the skull features. I thought may it might have been a reaction to the stain eating away the resin but I have tried to use watered down acrylic and I get the same effect. So it is something in the resin process. I am doing this in my basement which is about 65 degrees if that matters. Should I wash the mold before attempting to cast items in it? Is it possible I am rotating it too fast. I have had some skulls turn out just fine and some that have various lines like above. Thanks for taking the time to help.

What resin are you using? What mold release? What mold material? I will try to help even if it isn't our (Smooth-On) material... also are you roto casting by hand or machine? If machine does the x y axis spin at varying speeds or is it fixed?
Lots to know in order to get a better understanding....

One thing to note I have two separate skull molds out of rebound 25

Resin: 65D (have used 300 as well with same various pattern results)
Mold Release: Mann Ease 200 one mold I have used this on and one I have not used any mold release with the same various pattern results)
Roto Casting by hand

Thanks!