I have never done intarsia but I thought this product might be useful. https://www.stewmac.com/Luthier_Tools/Tools_by_Job/Tools_for_Sanding/StewMac_Sharkskin_Abrasive.html?lac_guid=db3d1747-3289-e811-80de-ecb1d775572a&utm_campaign=M1952&utm_medium=email&utm_source=EPA&utm_content=M1952_O_20180718