[Failure] gel pack arrived liquid and warm in July. photos at unboxing.
CPC, July shipment, Hangzhou to here. Gel pack fully liquid and noticeably warm to the touch, box interior warm, no logger unfortunately. Photographed everything before unpacking as usual. Powder looked normal, cake intact, no discolouration. Tested afterwards and it came back fine. Posting it as a Failure anyway,…
The specific failure here is almost certainly thermal mass rather than insulation. A single small pack in a large void has nothing to hold the temperature with; the pack exhausts and then the air in the box does whatever the outside is doing.
Two smaller packs plus a snugger void outperforms one bigger pack in a loose box, and it costs the same.
this is the specific engineering answer i wanted and could not articulate. the void was enormous, that is exactly what it looked like.
vendors who get this right and vendors who do not are visibly different on arrival, and it is the one quality dimension you can assess yourself with no laboratory involved at all.
which is why packaging scores are on the source pages. it is the only assessable-by-anyone metric we have.
60 shipments scored on five things. it is the most-read table i maintain and the least glamorous.