Thanks everyone! After so much hard work... these kind comments really give me a boost.
@SloJimFizz , Glad to hear it!
I have been increasingly obsessed with the wooden chamber insert. It greatly improves stem unloading/loading and gives a noticeable performance upgrade. Future plans are to offer these inserts as part of a capsule system that pairs the inserts with an airtight holder for easy carry and loading.... but that's a future project.
Apart from faster heat-up times, you also get more even vaporization around the outside rim. I attribute this to more uniform airflow (see my drawings a while back) and less heat loss through the chamber walls.
For optimal performance I grind very fine and then sieve the grinds through a steel mesh to separate out any large particles that need to be re-ground. I just do this once, and fill up a container full of perfectly even grinds, so it's not so inconvenient. Sounds like I am just being picky.... but hang in there!
I was first inspired to do this a long time ago from when I was into espresso. The grind consistency of the coffee is of absolute importance for even extraction... it only makes sense to apply this logic to vaporization as well. The added effort is worth it... and I could see a purpose built grinder with sieve already installed to accomplish this task easier.. perhaps an idea for another maker out there! haha.
The cool thing about this consistent grind is that you can tamp down the herb and it will form a sort of "puck" that stays firmly in place inside of the wooden chamber insert. This gives the ability to have "capsules" without the need for additional SS mesh. Loading and unloading is much easier this way.
I still keep two screens inside of the glass stem to cap each end of the wooden insert. I've included the addition of a stem loading/unloading tool with every Nomad, so that you don't have to pick the top screen out with your finger. Much improved.
Here is how it's loaded. I still believe this is the absolute best loading method. One advantage that I love, and learned from
@KeroZen , is that after each load you can swap the screen position. This constantly clears the top screen of any residue/particles, so your screens never clog. It's a self cleaning system, which is very nice!
The unloading tool is basically a push rod made from wood, the push rod doubles as a tamper.
In this first image, you can see the fresh herb loaded from the top. This side faces the heater. A light tamp was applied.
Here is that same side, after one long draw from cold, no pre-heat, standard (low) temp heater. Great vapor production and taste. This size load I would usually finish in two or three long draws.
Here is the backside, fresh, unvaped. This side is facing away from the heater.
Here is the same side after the above mentioned single long hit. Notice the evenness. around the outside rim. Also notice how this insert was taken out of the stem, and yet the tamped herb stays put.
Here is a split image showing both side by side.
And another split image from the other side. Herb appears a bit darker in this image because it's in shadow from being deeper down into the insert. In person, I could not see a difference in colour between the front side of the herb puck and the backside, this makes me think that there is perfectly even vaporization happening throughout the entire chamber load.
Notes:
For future experiments I'll be using briar burl for these inserts to see if that makes any difference. Briar is from the root-ball of a shrub that grows in very arid conditions, and so the wood is extremely good at soaking up moisture. This is why it's prized for tobacco pipes. Perhaps by using a larger briar insert we could get some of the same benefits. I also would like to experiment with a briar burl "filter" insert. Like a little wooden cooling unit. The wood could cool the vapor by drawing out the steam, which is exactly what it does in a tobacco pipe to provide a cool smoke.
Inserts of varying depths could be made for pre-loading. Micro-dose inserts could be used alone, or stacked in multiples, perhaps with different strains in each insert.
Oh yes, and everyone will be getting a wood insert with their batch 2 Nomads, last minute add-on!