Experiments
Steam Pre-Heating Experiment
The Background
The idea is to get a higher shot temperature out of the Forge than would be otherwise easily possible by pre-heating with just boiling water. First introduced on HB by Peter (beananimal) here:
http://www.home-barista.com/espresso-machines/espressoforge-first-impressions-t35885-160.html#p423659
The Setup
The Forge placed ontop of a Fino 1.2L kettle. My Forge has a small hole drilled in the top plate, which fits an instant-read type of thermometer. To get a more accurate temperature, I also added some Dow 111 to act as a thermal compound. Take note, this reads just the overall metal temperature, not exactly the temperature of the water or steam inside the Forge. Idea was to preheat the “group-head” to around 75C, then lock in the basket and pull using normal 100C boiling water to get a shot temp in an expected 80-90C range.
The Result
Conclusions
By taste, I can tell that the method definitely works to pull better highlights out of lighter roasts. So far, I don’t feel it’s necessary for most dark roasted coffees. The normal pre-heat method by using boiling water gives me excellent results. But to prove it a possibility I wanted to show my findings. Next step will be to get some Scace readings. If I can’t find a customer who is interested in doing this test that already has a Scace, I’ll be looking to pick one up. Anyone interested in loaning me theirs?
Does the hole in the top fo the forge go all the way through, or is it just down into the metal? Is it threaded?
The hole is countersunk and doesn’t go all the way through. It’s not threaded, but I did have the idea to thread it so that a thermocouple could be screwed on. Overall in testing I’m not sure accuracy is any greater than just fixing a thermal strip to the top.
Thanks Andre. I love my new Forge. I have just been preheating with boiling water while I grind. I will look for a thermal strip to put on the top. Keep up the good work.
Thanks! Yeah I would suggest the thermal strip if you’d like it to be more repeatable. Steam heating while a bit fiddly is nice in a couple ways beyond just being able to hit a higher temperature. It’s more self-contained and more water efficient. The “whistling” effect also lets me know when it’s getting ready like a teapot. Downside with this kettle is that sometimes needs to be adjusted as it’s heating up to get a good seal. Also, occasionally some water does come out the spout from the pressure building inside. Not sure why it only does this occasionally right now.