- Parts assembly adds more mass than you would think to an order
- Mass of a board is calculated by the bounding rectangle dimensions and the PCB thickness, so if you have areas cut out from a board it is still counted. You can see this in the quote screen.
- Thickness makes a big impact, but it can't be avoided if you want to use economic PCBA.
- A steep jump in price occurs at 0.3 kg, if it's above this mass the incremental jumps in price are less and it's generally not worth optimizing small combined orders to save on shipping (See last plot)
This is pretty good though if you are not a business and want to shave off as much cost as possible, it incentives making more revisions and shipping often, compared to bundling orders in one shipment.
However, it looks like assembly really overestimates the mass of the parts (or are they really this heavy in total?). When using assembly, the mass goes up to 0.39 kg total, which goes over some price breakpoint and increases the shipping cost to 14.90 AUD.
I will have to do some tests to see how the assembly mass is calculated (whether it is a constant mass for the number of items added or if each item has its own mass), since I really can't see some chips and passives adding 0.2 kg of mass. Also knowing how the shipping is calculated would be nice since it would let us know what the maximum amount of parts are to get 3 AUD shipping.
