Casting issues with jewelry

We have been trying to troubleshoot some jewelry casting issues and I’m hoping someone here may have some suggestions. We have a Form 2 and use the castable resin. We have a new cartridge and resin tray and the prints have been coming out very clean. We cure under UV light for 8-12 hours.
We use R&R plasticast investment and employ a centrifugal casting method.
I am attaching pictures of our most recent cast. You can see how the wax arm is very smooth as opposed to the ring shank. I want the casting to all be as smooth as the wax arm.
Any suggestions?

Photo link:

Links go to images that are not publicly visible. You might want to make it so that anyone can see them.

Thank you for pointing that out. I just edited the links so they should be accessible now.

Looks like ash porosity. What is your burnout schedule?

We have tried 8 and 12 hour burnouts and what you see in the pictures always seems to be an issue. We start at 300, ramp to 350 and hold for 30 min to 1 hr (depending on 8 or 12 hr schedule) ramp at 240 degrees per hour to 1350 and hold for 1.5-3 hrs then ramp down to 900 and hold til casting which is usually a couple of hours.
The instructions for the investment recommend a hold at 700 for 1-2 hrs after being at 350 and before progressing to 1350. I have not tried including this step yet since the Formlabs burnout schedule does not include it.
I did just get a programmable thermostat for my kiln and if anything I think it may not have been getting quite to temp because the original temp gauge seems to be just a little bit off. I can run a burnout with more accuracy now, but I’m not sure what I should alter in the schedule.

Not hot enough, not long enough. 1425 for 5 hours. 1/2 way to casting temp, vacuum flask.

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