Can I use a marking spray on an aluminum buckle to score?
Posting in Problems and Support opens a support ticket, and this is outside their scope to help you with. I’m going to move this over to Everything Else for you.
From everything I’ve read on the subject bare aluminum is tough to mark with those sprays. Some people have had good results but usually with 60 or more watt lasers. I guess you could always have a go at it and maybe you’ll find a setting that works just right.
Anodized and painted aluminum is easy to mark with the GF.