yakster wrote:Wow, the crossbow mod sounds pretty interesting, but I think the direct model sounds the most practical.

Haha! Not that I'm advocating something that dangerous... but ideas!

SlyTerrapin wrote:I love the simplicity and ruggedness of your design, and congratulate you on hopefully bringing an interesting and affordable product to market. However, there are two issues that would prevent me buying from the initial batch at present:

Temperature stability. I know this has already been raised and you're looking into it, but i was wondering if you thought a portable element (something like this: http://www.amazon.co.uk/gp/aw/d/B007OVCSSU/) would work if slipped into the neck of the EspressoForge? I'm not suggesting this should be included with the product, but i would probably buy one to complement the device.

The second issue i have relates to the length of preinfusion, starting from the first drops poured into the devise. Would it be possible to incorporate some sort of valve to stop the water hitting the puck until the cylinder is full and you start to apply pressure (something like this: http://www.tom-parker.co.uk/products_su ... ups=8610AG).

Once again, i think it's a great idea and i'll be following the development of the product with interest.

Thanks for the compliments. I don't expect an initial run to be for everyone since some things about espresso machine design are really and truly trial and error. Engineering is just like that, and while calculations and formulas give you data, they don't always tell you how it will work in real life. I had only some idea if the device would work, but not exactly how well or with what ergonomics. So far it has far exceeded my expectations.

Temp stability gets talked about a lot, but I think this has a lot to do with traditional espresso machine design. A lot of metal, usually brass, which absorbs a ton of heat means that if everything isn't up to temp, the water hitting the coffee will get significantly cooled. This machine is a lot different in my opinion, however that doesn't mean that I know everything about it yet! This is why temp data will be important to some people. Although I was hoping a bit that someone else would take up the reins here, since if I do a temp analysis and it comes out great...would everyone believe me? I haven't tried to sell the device above all else, but non-biased data is always better and more real. In the end, doesn't it matter how the shots taste? So while I'm all for data, right now with the prototype I'm getting great shots, especially from light roasts.

Preinfusion and other things inherent in the design may be some of the reason why conventional mechanics are different in this machine as opposed to other machines. You could certainly add a valve or any NPT type bushing/fitting to go inline with the pipe, but from my research on parts, this will be too expensive for the design. Certainly it could be an add-on device or aftermarket addition or mod...but if it costs $50 or so, would it be worth it? If it reduced shot volume significantly, would it be worth it? Etc.

I'm all for innovation on the device, so I'm sure more things will come. One person asked me about if someone pre-orders, could they get a discount on v2 model etc. I think it would be very doable, although profit margins aren't big unless I start making a ton of them overseas, I would plan to give some discount or upgrade parts free to the first supporters of the project. And I hope the first users will do all kinds of crazy tests and put the machine through the gauntlet so to speak.

EspressoForge wrote:Also for those asking if the tripod stand is necessary. I think that it's a good idea since it provides a stable (wider) base, but there's no need for it depending. I usually use it since I drink mostly straight shots and pour into a small espresso cup. But the few mugs I have lying around the house seemed to be a perfect fit:
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Actual dimensions of the final lower ring will be 88mm OD and 61.5mm ID.

Really surprised that Microsoft mug is compatible with your unit. I didn't think their products were compatible with anything else...

rittem1 wrote:Really surprised that Microsoft mug is compatible with your unit. I didn't think their products were compatible with anything else...

Haha! Surely a fluke...

SlyTerrapin wrote: The second issue i have relates to the length of preinfusion, starting from the first drops poured into the devise. Would it be possible to incorporate some sort of valve to stop the water hitting the puck until the cylinder is full and you start to apply pressure (something like this: http://www.tom-parker.co.uk/products_su ... ups=8610AG).

I touched on this in my earlier post, about possibly adding a low pressure check valve, but thinking about it, I think you would lose a lot of shot volume. I think a good amount of water volume sits below the pipe (between pipe outlet and shower screen). I also wanted to note, the shower screen already does offer some resistance, even by just pouring water in a bare shower screen out of the unit, it slowly drips out. When it's in the device, I bet that puck wetting isn't happening as fast as you might guess, and water is done pouring in less than 10 seconds. But that's just a guess too.

Thinking of ways to test this, I could lock in a puck, pour water, then immediately pour it back out once full and see how wet the puck gets (by dissection!). It would seem a bit wasteful of coffee, but maybe if I get a bad roast or some old coffee from someone I could try it.

SlyTerrapin wrote: but i was wondering if you thought a portable element (something like this: http://www.amazon.co.uk/gp/aw/d/B007OVCSSU/) would work if slipped into the neck of the EspressoForge?

I wanted to say specific to this, I would doubt that an immersion heater would work well in this unit directly. The first problem I see is that the pipe is so tall and slim that you would have to have a much smaller element and run it up and down to mix the water properly. The second is that instead of 5-10s of the wetting time, you would have a much longer wetting time, which I would feel that would no longer be negligible. You could try to do it with the piston inserted slightly, whole unit inverted, and the shower screen off. Heat up water inside unit, pop on the shower screen, invert basket (fits pretty easily onto shower screen), and then lock on the ring. Reminds me of the inverted Aeropress method in some ways, but I have a feeling because of the length of the tube the workflow will be a LOT more difficult than using it upright. Not to mention that the water may not evenly heat, but I could be wrong.

Another friend of mine and I were talking about pre-heating and we thought that a blind basket with a small hole in it might make things a bit easier. Right now you fill the device, then wait some amount of time, then pour the water back out to preheat. But a disc with a single hole may allow a more controlled flow of water through the device. I'm not sure if it would make preheating more controllable, or would end up about the same.

Sorry, had meant to reply more in detail to these points in your post earlier, but I think I got myself sidetracked.

I love how we are already modding this device!

Haha! I can't wait to see what people come up with once they get them...

Speaking of, pre-orders are now open. I have 8 devices left at the time of writing (my website will show how many are left). You can get the link from my profile.

And a big thanks to everyone who has supported the project this far. Custom parts are still being made, the machinist has promised me picture updates, will post them here as I get them!

Haha what would really be awesome would be to dedicate one lower cabinet drawer to this and Gilberto's grinder. Make an induction coil that wraps around the tube with precise low temp control, build it into the counter and your air presso slid into the coils to allow for instantaneous precise control, and with his grinder next to it.

Dont forget the external LCD display of the pressure gauge and a second of an in drawer scale mounted on the wall behind them.
Precise control, stability grinds and temp in a couple of inches of visible shelf space:) hehe

Is my vision coming across?

Awesome! Are you planning to do it?

BTW I figured out a cool trick a couple days ago I forgot to post about. When you're done with the shot and want to cut it, all you have to do is raise the piston past 0 psi a bit to create some negative pressure, stream and all drips stop nearly instantly. Much less fuss and mess than trying to slide another mug under the device while it's still pouring.

I'm planning to make another updated routine video with some small modifications to my process that I've made over time. But it likely makes sense to do with the new production units when they arrive.

Milling production top plates is coming along well!

Got some of the other non-custom parts in. Today I was able to cut and polish the rim of the stainless pipe. All went well there. Had some diamond/rubber polishing bits that worked very well to get it nice and smooth. Now will have to polish the entire inside as it's a bit rough. Planning to use sandpaper with water as a lubricant and getting it to near mirror finish inside. I think this will improve the performance of the machine and o-rings a lot as well. I learned just how hard stainless is with this process! The final unit will be extremely tough, you could probably use it as a hammer.

Stay tuned for updates! I'm still targeting end of April to ship out units, but it could very well be sooner. Main thing that could cause delays is that I want to test out a unit fairly extensively to make sure everything is up to standard with the prototype. Just in case I have to change my polishing or other finishing routines. As long as nothing needs tweaking it looks like early shipping may be likely.

Have a look at:

http://www.brushresearch.com/

Ira