Chinese ALM lever

#1: Post by **Jonk** » April 7th, 2021, 5:51 pm

Saw this in the OE-1 thread:

https://www.aliexpress.com/item/1005001992968590.html

..and thought it looked absolutely funky

Don't share the criticism at all that it runs on gas.
A lot going on in the picture. Perhaps someone would like to translate?

Sure, the price is not competetive - you could buy a much better polished, convenient and proven Elektra MCAL for the same price. But at least it's something completely different.

#2: Post by **zix** » September 4th, 2021, 10:15 am

Looks fun! The first gas heated small lever I have seen. Not counting the Bacchi espresso of course, since you can only do one shot at the time with that.
I would like to do something like this with the Caravel. Find it more suitable for camping, better form factor with less stuff protruding here and there.

September 4th, 2021, 12:50 pm

Google translate:

#4: Post by **renatoa** » October 10th, 2021, 10:49 am

Chinese poor man's "Strietman", now moded with heater and PID:

#5: Post by **Nunas** » October 10th, 2021, 5:19 pm

renatoa wrote:Chinese poor man's "Strietman", now moded with heater and PID:video

Thanks for the video. It's an interesting machine. However, I'm puzzled why the temperature drops so much while pulling the shot, yet you say it's a super stable machine. BTW, I searched Alibaba and AliExpress and could not find this model with inbuilt electric heat.

October 10th, 2021, 6:53 pm

This device w/o pid has been around a few years here is a comment about it in 2019 (there are a few more posts about it if I recall) Chinese Caravel/Flair/Robot

Since the cylinder and group where Portafilter locks in is all stainless and not heat soakable brass the Portafilter and Lower cylinder/group area did not heat properly.

As the piston raises the water moves from the hot area of the cylinder where the sleeve/hot water is and below the piston where it encounters the colder areas of the stainless and temp begins dropping probably faster than it is recording.

Maybe by preheating pf which could be chromed brass you could help hold temp up a bit longer

Strietman uses brass group/cylinder with a stainless sleeve (on current model has sleeve) ...to give best characteristics of stainless for piston movement while keeping the heat characteristics of brass stabilizing group temp. Strietman uses 2 cartridge heaters inserted in a brass block that is bolted to the cylinder.

#7: Post by **Nunas** » October 10th, 2021, 7:19 pm

Thanks! I knew it had to be too good to be true

#8: Post by **vit** » October 11th, 2021, 1:24 am

From the video, it looks like the probe was attached to the upper side of the piston (I suppose he wasn't drilling it). When he raised the piston, water flowed below it, and the rest evaporated, lowering the temperature above the piston. So I think the measurement is meaningless for the brew water temperature

From my remembering, there was a similar meaningless measurement on Flair58 on an early review

Specific heat capacity of brass is lower than of steel btw ...

#9: Post by **renatoa** » October 11th, 2021, 4:09 am

@vit is right, during extraction the probe is no more in contact with water.

Regarding heating, my guess is that probe is not a simple probe, but a heater-thermocouple combo cartridge, there are such devices having hundreds Watts and the size of a finger. So the PID controlled water heating could be done inside the cylinder, not by the sleeve.
The sleeve, with 36 Watts, will never be able to bring the water to +90C temperature in acceptable time. To compare, Flair heater is 75W, also just for maintaining stability, not for effective heating, and CT2 heater is 500W, and needs 10 minutes to bring the water to boil.
PID-ing this machine is just a fancy dress, is much convenient to fill with boiled water and let the sleeve doing its job, to keep temperature in a 2-3 degrees window for some minutes.

October 11th, 2021, 9:52 am

vit wrote:From the video, it looks like the probe was attached to the upper side of the piston (I suppose he wasn't drilling it). When he raised the piston, water flowed below it, and the rest evaporated, lowering the temperature above the piston. So I think the measurement is meaningless for the brew water temperature

From my remembering, there was a similar meaningless measurement on Flair58 on an early review

Specific heat capacity of brass is lower than of steel btw ...

Just to clarify I was commenting on the design without PID from 2019 that required kettle water not the updated version with PID that Brian reviews.

Also I should have explained that the thermal conductivity of brass is far greater than stainless (like 10x or something while 2x for carbon steel) so it distributes the heat instead of insulating it (heat soaking it). Stainless basically act like an insulator since the heat stays on the surface (cylinder wall). This is not a bad thing look at the robot