Hey there - I'm running into a problem with our web shop. We sell music digitally, on CD and on vinyl. The weight of the packaging required to ship CDs is negligible, but the weight for LP mailers is more significant, and effects postage rates.
In our old e-commerce platform, we were able to set it up such that, if an order contained an LP, the weight of a single mailer was added to the order. If there were no LPs included in the order, it wouldn't add any packaging weight.
Is there a way I can set up my shop to add the "Default Box" ONLY to orders that contain particular SKUs, and leave the rest alone? This seems like a really basic feature but I can't find out how to do it!
Currently, there is not a way, using the default shipping settings, to set shipping rates on a per product basis. I am aware that many others have requested this function also so I'm going to add your name to that list -feedback like yours is exactly how we determine what features to add next. If you'd prefer to be as accurate as possible there are apps that can help with this such as Better Shipping.
In the meantime, what you can do is set your default package weight to be an average between the cost of a CD and the cost of an LP relative to how many orders for only CDs vs orders with LPs you get. This way, you won't be losing or making money on shipping. It seems you already know this but just in case, in the USA and Canada you can add multiple package types, choose the appropriate package size at fulfillment and pay for the associated rate to that package type.
I don't have an answer to your shipping question from almost two years ago, but would love to know if anyone has offered a solution. We're also a music sales site with the same trouble - especially problematic when a customer wants Priority and the package size matters a great deal. We scare customers away with high shipping if we default to large LP mailer but often undercut our costs when we default to small... Shipping profiles on a per-item basis is not a great solution as we offer thousands of items and I can't seem to scroll through our entire inventory to add more than a handful of items. Hoping there's help on the way for merchants like us!