How would you model this? Locomotive louvers

 From:  twofoot
10374.1 
Not sure how to get that stamped out look to the shape, could use a little help. This is for a model that will be 3D printed in resin. I tried to show a typical model and then the actual louver shape from several angles.

Thanks!

Chris

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louvers

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thumbnail-IMG-4593

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thumbnail-IMG-4606

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MM-TIR500-17