A number of people have queried why international postage is so expensive. The simple answer to this is "it's what Royal Mail charge me" - in the grand scheme of things I'm barely a rounding error so I cannot negotiate volume-based rates.
In common with other carriers, Royal Mail now use a combination of weight and volumetric-based pricing, and the prices I quote are based on figures for an 'average' order (typically a small parcel weighing approx. 200g). This is far from an ideal solution, but it covers pretty much all the bases.
If I can ship something in a large letter-sized box (eg. a 2HP module, PCB/panel etc.) then the postage is often quite a bit less, even for 'bigger' items eg. an XO106r5 PCB/panel/firmware set weighs around 130g - PCBs are pretty heavy.
IT IS MY POLICY TO REFUND ANY 'EXCESSIVE' POSTAGE - meaning that if you ordered, say, a PCB/panel set then Shopify would tell you that it's £17.50 shipping - in reality, it's more like £13 including packaging so it's quite likely you'd end up with a refund of around £4 once I know the final shipping cost. These refunds generally get processed once your order has been fulfilled.
Note, however, that prices do not include any sales taxes - I'm not VAT registered due to being a long way below the VAT threshold, which means that you will invariably be liable for things like VAT and import duties. In some cases, such as US sales tax and Australian GST, Shopify makes the deductions at source - unfortunately, this doesn't apply to EU VAT (don't ask me why, I have absolutely no idea - EU VAT rates appear to be much simpler than the Hell that is US sales taxes)
Hopefully that will clear things up a bit - if you think the 'regular' shipping rates are bad, take a look at what the couriers charge. There are very good reasons why I only offer courier shipping on request now.