Open Source Lever Project - Page 9

December 30th, 2015, 5:13 pm

Just to throw out other options, besides the 390 EUR CMA group, theres the 240 EUR Portofino group and the 140 EUR Pavoni manual group.

OldNuc wrote:Aluminum in contact with hot water is a disaster of rapid corrosion and soon holes. Stainless steel is nice but construction is expensive and machining is likewise. Brass, bronze, or copper are actually the best low total expense DIY options.

I agree, the idea with the Ascaso thermoblock is supposed to be a stainless heating element and stainless tubing that has aluminum cast around it.

dominico wrote:In the case of Ascaso in particular, I hounded them until the came up with a name for an American Distributor for me: Heritage Parts. Not many Ascaso parts are on their website but you can find it in the Ascaso catalog and contact Heritage and they will fill the order for you, a bit of a hassle but less so than a bank transfer, which I have also done before, to the tune of a 30 euro fee.

Interesting, I'll have to contact them, maybe it will make the ordering process easier (harder would be quite a feat).

#82: Post by **dominico** » December 30th, 2015, 5:19 pm

They came through for me on what I thought were unobtanium parts when I cracked the preinfusion adjustment nut on one of my Faema lever groups

#83: Post by **bm_cricket** » December 30th, 2015, 5:23 pm

EspressoForge wrote:Just to throw out other options, besides the 390 EUR CMA group, theres the 240 EUR Portofino group and the 140 EUR Pavoni manual group.

I agree, the idea with the Ascaso thermoblock is supposed to be a stainless heating element and stainless tubing that has aluminum cast around it.

Interesting, I'll have to contact them, maybe it will make the ordering process easier (harder would be quite a feat).

I'm having a hard time finding those other parts and visualizing what they look like. Could you post photos? Are they the levers used in lever style machines, or "manual" machines?

#84: Post by **bm_cricket** » December 30th, 2015, 5:25 pm

OldNuc wrote:Aluminum in contact with hot water is a disaster of rapid corrosion and soon holes. Stainless steel is nice but construction is expensive and machining is likewise. Brass, bronze, or copper are actually the best low total expense DIY options.

Aluminum is bad... but super easy to cut. I'll probably prototype in aluminum but I know that using it in the long run is awful. Really awful! I should research the costs for a brass sheet. McMaster-Carr sure seems expensive for that stuff.

#85: Post by **bm_cricket** » December 30th, 2015, 5:30 pm

bm_cricket wrote:I'm having a hard time finding those other parts and visualizing what they look like. Could you post photos? Are they the levers used in spring and lever style machines, or "manual" machines?

December 30th, 2015, 5:43 pm

bm_cricket wrote:I'm having a hard time finding those other parts and visualizing what they look like. Could you post photos? Are they the levers used in lever style machines, or "manual" machines?

Brasilia Portofino Group (pic looks close...but may be slightly different):

Pavoni is the standard one used on the Pro/Europiccola:

#87: Post by **OldNuc** » December 30th, 2015, 5:47 pm

bm_cricket wrote:Aluminum is bad... but super easy to cut. I'll probably prototype in aluminum but I know that using it in the long run is awful. Really awful! I should research the costs for a brass sheet. McMaster-Carr sure seems expensive for that stuff.

Online metals can be lower cost but watch shipping. http://www.onlinemetals.com/ Small orders of any metal, sheet or pipe, is expensive.

December 30th, 2015, 5:48 pm

bm_cricket wrote:... And if the parts catalog I found and the video diagram posted earlier in this thread are true (4 coils of pipe around 4cm in diameter) and the parts catalog shows the inlets/outlets as 4mm pipe then I think the thermoblock will hold around 6ml of water, or 0.21 fluid oz. I think I rounded down on everything so it could be a little higher than that. But it still means about 10x that much water will need to go through the block to get to the right volume for a double shot. And heating water up from the thermoblock will be hard. The water takes 10x more heat per degree than the aluminum block does. It isn't perfectly linear in real life but that means the block would need to be quite a bit warmer than desired to make the water come out the correct temperature.

So, if I understand correctly, then the idea of the thermoblock also heating the group can be abandoned because it would overheat the group?

FWIW, IIRC Pizzaman runs his group heaters at 212F.

#89: Post by **bm_cricket** » December 30th, 2015, 5:49 pm

OldNuc wrote:Online metals can be lower cost but watch shipping. http://www.onlinemetals.com/ Small orders of any metal, sheet or pipe, is expensive.

That makes perfect sense... I guess that those of us who try building one of these will go down the road of making friends with local metal fab shops. It's a community building activity!

December 30th, 2015, 5:53 pm

Some local metal suppliers also let you pick through scrap bins at a discount if you have the time and can identify what you're looking for, or aren't too picky. I've never been able to do that since without complex tests I wouldn't know how to make sure I got 304 stainless. With copper, brass or bronze it should be easier.