Hi @nick-wernicke,
Most of the penetrators we pot are oven cured, and that speeds up the process a lot, taking only a few hours. However, we do cure all our potted tethers in air in a room that is about ~15-20°C right now. Once they cure undisturbed for 4 days, they are solid enough to handle without damage, but they do continue to cure a bit more while they sit in inventory and are shipped to customers. 10°C is quite low and will increase the cure time a lot, the instructions on the cartridge are a general guideline assuming comfortable room temperature.
Four days at room temperature (~21°C) should be a comfortable minimum, and I would only suspect that something is wrong if the potting is still gummy after 6-7 days or so. You should definitely at least turn a heater on if the temperature is significantly below this baseline. Putting them in the oven now should help, but in varying the curing temperature too much during this process can have adverse effects in some of our limited experience. We always commit to either full oven cure or full ambient cure, and don’t normally mix them.
The potting technique shown in the video and instructive tutorial is the correct method that we recommend and have been using exclusively in production for almost a year, for both tethers and thruster penetrators. Potting the back is unnecessary and will not increase seal performance. The only goal is to seal the cable jacket, as the individual wires are not sealed, and air/water can leak between the wires and within the wires between the individual wire stands. This is why it is important to ensure the cable jacket is not cut in any place, otherwise a leak will result.
-Adam