Hi Al, got your message. Are the leaves with the problems at the top of the vanda keiki or at the base? Do your plants dry off fairly quickly or do they stay damp after watering for several hours? Do you have a better shot showing the leaves on the plant? Sorry for all the questions, but it could be normal die off or it could be caused from poor air movement or like you mention, it could be the oil and sun causing a burn. Hard to tell from the photos you have here currently. Sorry.