If all a mechanical engineer can come up as a "redesign" is to make a device work for a different set of conditions and not work in the original conditions, he or she should find another job. A better design would, by definition, mean that the device works under a greater number of variations in the underlying conditions. So I agree with you 100%, making it work for me and not for you is not an option.
A possible redesign for bottom coils would be the addition of a more or less predictable juice flow control mechanism. For example, a small nut instead of the silicone cap over the coil chamber. Tightening the nut would restrict juice flow into the coil chamber and viceversa.
A possible redesign for bottom coils would be the addition of a more or less predictable juice flow control mechanism. For example, a small nut instead of the silicone cap over the coil chamber. Tightening the nut would restrict juice flow into the coil chamber and viceversa.
Nothing works for everyone. We all vape differently, draw differently, use different juices, wear different clothes. That doesn't mean that "the bottom coil design need a little more work".
The cartos that you mentioned that work great for you all don't for me, but the BCCs do work for me. Should they redesign the top coil cartos that you like so that they work for me?