1975 La Cimbali M15 Lever Just Arrived! - Page 3

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dmccallum
Posts: 136
Joined: 11 years ago

#21: Post by dmccallum »

LaCrema wrote: It looks like you had a nice large square of gasket material, what are your thoughts about making your own gaskets for the entire boiler assembly?
I use a company that specializes in custom CNC cutting to your design. Here's someone I use in the UK (http://www.par-group.co.uk/sealing-and- ... g/gaskets/). Note the range of possible materials. Suggest PTFE..

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LaCrema (original poster)
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#22: Post by LaCrema (original poster) »

Hey Guys,

In response to a few posts about gasket suggestions, I did a Google search on some gasket material John had in one of his pictures and I think Paul also uses this same material to do his restorations. I Googled "ICP 9200 Gasket" and came up with the manufacturer Calvosealing http://www.calvosealing.com/products/Co ... 9200/68/en that's out of Spain. They manufacture tons of different materials for a large variety of applications, although only a few would be "safe" for this application due to the materials used in the gasket material. They have a pretty extensive downloadable catalog, looking through it gave me a couple possible alternatives to gaskets that are currently manufactured for the M15. According to their catalog they also manufacture a higher temperature and slightly more compressible material, the ICP 9400 gasket. The ICP 9400 gasket http://www.calvosealing.com/products/Co ... 9400/70/en offers a higher working temperature that would seem more beneficial to use rather than using something (the ICP 9200 material) that's consistently used at a level closer to it's maximum operating temperatures. I was also thinking that a material that's slightly softer like the ICP 9400 may seal better at lower torque values (on the boiler rings), this maybe easier on the metal rings while reducing the probability of leaks. I'll contact the manufacturer and ask about it's compatibility with my application to make sure it's "food safe."

So after looking at all the pictures John posted of his M15 I was inspired to take the side covers off my machine to see what's going on inside, unfortunately I verified that indeed there is no pressure stat of any kind on this machine. There are a few areas I think can add a thermocouple, one on the boiler and one on the group head; this should be sufficient for a PID but my knowledge on PIDs is poor. I've seen this done on Silvias, but that's 110v, not a 220v application... any advice? If I do PID this machine I'm not planning on mounting it anywhere visible on the outside, I would prefer to mount it on the inside and maybe underneath the drip tray since I don't think I'll be using it for anything other than stabilizing the boiler temperature. Although this machine doesn't have an electrical pressure stat, it does have a thermostat for the gas block. The thermostat comes off a 2-way split off the boiler for the pressure gauge on the front of the machine and the other goes to the gas valve assembly, this split also has a valve that could be used as a manual adjustment in conjunction with the base unit where the gas adjustment valves are located.

Overall I'm impressed with the overall build quality of this machine as it seems to be tighter in tolerances than my newer La Cimbali D1 Junior.

I'll post some new pics, let me know what you think.




2-way valve for gas-block thermostat and the pressure gauge in the front of the machine.


Thermostat and adjustments for the gas-block.


Possible thermocouple mount on upper left side of boiler.


Another sensor for gas-block.


















Another potential thermocouple mount?


The dark stuff on the frame is really sticky and oily?







Lots of pics, share your thoughts.
"Outside the box Barista."

mdkmdk
Posts: 30
Joined: 11 years ago

#23: Post by mdkmdk »

Hey there, I received an old Cimbali M20 lever earlier this year. The group head looks identical in which case you can find a number of parts at caffe parts, espresso parts and theres a dealer in Pelham, NY that gets old machines and was able to help me with some hard to find parts on my machine. I also have some extra portafilters if you're interested. I'd call the guy in Pelham just to ask about interchangeability with the M20, bc if they are you'll be able to find a lot. Caffe parts, for instance, has the shower screens you asked about earlier.

Once you get this up and running you'll love it. They're very temp stable and really excel at single origins.

Out of curiosity, where was the plate with the manufacturing year? I've never found a year on my machine; best guess is early 80s.

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LaCrema (original poster)
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#24: Post by LaCrema (original poster) »

Hi Michael,

I was thrilled to hear about your M20, I have a couple Cimbali Juniors and love the design and performance of those machines! I'm actually interested in trying to find a mercury pressurestat for my machine, unfortunately I don't have enough privileges to post such a request in the Buy/Sell section of this site so I'll have to wait until I have the appropriate credentials.

I'm currently rebuilding an S/1 Junior for a friend, the bottom pan and frame are bent in several places due to incorrect packing and UPS for allowing it to "fall off" their conveyer system. On the Junior there is a small metal tag that's attached to the overpressure valve on the boiler, mine appears to have been manufactured in 1989.



I looked at the metal cover under the drip pan and it has a couple serial numbers, but it doesn't appear to reveal any date in that number. You could contact LaCimbali and see if they could give you more information on the manufacture date based upon the serial number and go from there?

I'm starting to tear into the M15, but I'm addressing the parts list and starting with the gaskets. I emailed CalvoSealing in Spain last week, unfortunately I haven't received a response as of yet and might source my gasket material from a different supplier. I was able to remove the nuts that secure the grouphead assembly to the boiler, unfortunately I broke a stud off because I didn't heat it, Arg! I was planning on replacing those studs later along with a laundry list of other things, so Game On! I'll post some pictures of my current findings and continue to post updates on my project.

Thanks for the parts sourcing suggestions, I want to make sure I'm well armed with sources to make sure things go pretty smooth from start to finish on this project. I'm still in need of an acceptable wire source that would be appropriate for this project. Home Depot simply doesn't have the "right stuff" that will look right in my machine (and the S/1 project) any suggestions?

Time to fire up the Silvia...

Thanks!
-Eric
"Outside the box Barista."

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LaCrema (original poster)
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#25: Post by LaCrema (original poster) »

So I became a little impatient and wanted to see if I could get those nuts off the studs that hold the grouphead to the boiler... well I snapped off one stud, but got them all off without heat. I later heated up the nut with broken stud and removed the broken part of the stud so I can reuse the old nuts later when I'm ready to reassemble this thing.



I took a few pictures inside, the heating element appears fully intact with only a little buildup. The boiler looks pretty good inside from what I can see so I'm really happy so far!







This is the old scale buildup line...


Grouphead assembly.




The "sippy straw" came off easily with a 17mm wrench.... Touché!


I'm thinking about going to Home Depot to source a plastic container that's large enough to soak these parts in a hot bath of Urnex or Puro to remove the old coffee residue, then later I'll soak the other parts in supersaturated citric acid bath and go from there.

I want to save the diagram on the inner panel that shows the wiring diagram for the pressurestat. I don't know if I'm going to have the panels painted or powder coated, I guess that all depends on my color choice? I'm not sure what my color limitations are (if any) with powder coating. Since I plan to keep this machine for myself I would like to use a color that Aprilia motorcycles had on their RS250s, it's a orangish-red that's almost fluorescent but not quite. I'll have to ponder that a bit, it might be a little loud but I kinda want this machine to make a statement. The nice thing about paint is that it's not forever if I get sick of it. :wink:

More to come...

-Eric
"Outside the box Barista."

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LaCrema (original poster)
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#26: Post by LaCrema (original poster) »

So I removed the "straw" from the group that goes into the boiler and soaked it in Puro just to see if anything would happen... nothing happened. I've been combing this forum and found all sorts of people leaning both ways on how to appropriately descale the boiler. One thing I didn't like with my previous experience using the Citric Acid was that it left everything looking copperish in color, even the brass! I've seen others descale their machines and everything looked like new from their results, what was I doing wrong with my Silvia?

This time I'm ready to tackle the job, I have 30# of Citric Acid on the way from eBay and purchased 2 gallons of Muriatic Acid (<30% HCL). If I use the Muriatic Acid I'll dilute it down to a 6-7% solution and make it nice and warm for the soak, checking on it frequently to see what's happening. If I use the Citric Acid route I'll do the same, but I'm sure I'll have to do some polishing to remove the copperish residue that's left behind on everything. Anybody have any suggestions to avoid the copperish residue left behind?

One more thing... I did see somebody use a wire brush on a drill to remove an excessive amount of build up from their boiler, I might try this option to lightly scrub away the residue, then a short soak in one of the two solutions followed by a strong solution of baking soda bath to neutralize the acid and finally clean with Dawn dish soap for piece of mind.
"Outside the box Barista."

turboyeast
Posts: 143
Joined: 11 years ago

#27: Post by turboyeast »

LaCrema wrote:So I removed the "straw" from the group that goes into the boiler and soaked it in Puro just to see if anything would happen... nothing happened. I've been combing this forum and found all sorts of people leaning both ways on how to appropriately descale the boiler. One thing I didn't like with my previous experience using the Citric Acid was that it left everything looking copperish in color, even the brass! I've seen others descale their machines and everything looked like new from their results, what was I doing wrong with my Silvia?
This time I'm ready to tackle the job, I have 30# of Citric Acid on the way from eBay and purchased 2 gallons of Muriatic Acid (<30% HCL). If I use the Muriatic Acid I'll dilute it down to a 6-7% solution and make it nice and warm for the soak, checking on it frequently to see what's happening. If I use the Citric Acid route I'll do the same, but I'm sure I'll have to do some polishing to remove the copperish residue that's left behind on everything. Anybody have any suggestions to avoid the copperish residue left behind?
One more thing... I did see somebody use a wire brush on a drill to remove an excessive amount of build up from their boiler, I might try this option to lightly scrub away the residue, then a short soak in one of the two solutions followed by a strong solution of baking soda bath to neutralize the acid and finally clean with Dawn dish soap for piece of mind.
A lot of questions, but I'll give you a short answer. Acid dissolves brass which consists out of zinc and copper. Zinc remains dissolved but copper precipitates, hence the salmon/pinkish color. You can easily remove it with a fine wire brush or steel wool. Citric acid at 10% is gold standard for removing calcium. You can use any other acid, but proceed with caution.
Finally, keep acid away from your aluminum boiler rings...acid will eat them like candy.
Cheers, TY

ps. I have refurbished a hydraulic M15...great machine. https://www.youtube.com/watch?v=DkkJLOGfzh4

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LaCrema (original poster)
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#28: Post by LaCrema (original poster) »

Hey Ty,

Thanks for your input! I'm beginning to learn more about the best way to approach this descaling challenge. I've read a lot of different posts in this forum with different approaches and opinions as to which "is" and which "is not" the best way to approach the descaling part of this restoration. Overall I feel confident in concluding that whether using a lower solution of Muriatic Acid (HCL) at about a 6-7% solution and as you suggested a 10% solution of Citric Acid, both approaches are effective but they also need to be closely monitored to make sure damage to the parts doesn't happen. I think taking it another step and neutralizing the acid(s) is a good safeguard to reduce the possibility of continuing the "reaction" between the acid and metals. Thanks for the extra advice about the aluminum, that could have been a costly mistake if I didn't know that!

I'll start with the Citric Acid since I have 30 lbs of the stuff on it's way, I can always return the 2 gallons of Muriatic Acid to Home Depot if the Citric Acid does its job. I'll take a wire brush to the pieces after descaling, maybe it might be better if I use a brass brush versus steel brush to avoid damage to the parts since brass is softer?

You know, I wonder if anybody has suggested using a vibrating parts cleaner? I use one for cleaning small brass parts and it works like a charm! You can also purchase large ultrasonic parts cleaners on eBay for pretty cheap, I wonder how effective something like that would be against calcium and other stuff that's on the surface of these parts?

Thanks for the link to your M15 video, I'll bet it was pretty exciting to get such a nice shot on your first pull?! I can't wait to finally try mine out after finishing this project!

Thanks again Ty for your help and suggestions, it's GREATLY appreciated!

Sincerely,
Eric
"Outside the box Barista."

turboyeast
Posts: 143
Joined: 11 years ago

#29: Post by turboyeast »

LaCrema wrote:Hey Ty,
Thanks for your input! I'm beginning to learn more about the best way to approach this descaling challenge. I've read a lot of different posts in this forum with different approaches and opinions as to which "is" and which "is not" the best way to approach the descaling part of this restoration. Overall I feel confident in concluding that whether using a lower solution of Muriatic Acid (HCL) at about a 6-7% solution and as you suggested a 10% solution of Citric Acid, both approaches are effective but they also need to be closely monitored to make sure damage to the parts doesn't happen. I think taking it another step and neutralizing the acid(s) is a good safeguard to reduce the possibility of continuing the "reaction" between the acid and metals. Thanks for the extra advice about the aluminum, that could have been a costly mistake if I didn't know that! I'll start with the Citric Acid since I have 30 lbs of the stuff on it's way, I can always return the 2 gallons of Muriatic Acid to Home Depot if the Citric Acid does its job. I'll take a wire brush to the pieces after descaling, maybe it might be better if I use a brass brush versus steel brush to avoid damage to the parts since brass is softer? You know, I wonder if anybody has suggested using a vibrating parts cleaner? I use one for cleaning small brass parts and it works like a charm! You can also purchase large ultrasonic parts cleaners on eBay for pretty cheap, I wonder how effective something like that would be against calcium and other stuff that's on the surface of these parts? Thanks for the link to your M15 video, I'll bet it was pretty exciting to get such a nice shot on your first pull?! I can't wait to finally try mine out after finishing this project! Thanks again Ty for your help and suggestions, it's GREATLY appreciated!

Sincerely,
Eric
Hi Eric,
I think that hydrochloric acid is also effective, but I have never bothered trying because citric acid works perfect for me. And why risk problems with diluting hydrochloric acid etc. I don't think it is required to neutralize citric acid, just rinse with lots of water. Yes, be very -very- careful with you aluminium boiler rings. They cannot obtained anymore. As an experiment just throw your steamvalve (with thee aluminium label) in 10% citric acid and watch what happens after 1-2 hours. Afterward discard this steamvalve anyways and replace it with a brand new one. This is a very important safety measure.

If your boiler contains lots of scale you might want to hammer the rim of the boiler carefully with a rubber mallet. You might be able to release chunks of scale that would take a long time to dissolve in citric acid. I have used a ultrasonic bath for small parts. It works great, but cleaning greased parts will be more efficient with acetone (for example) (followed by ultrasonic cleaning).
Yes, the M15 is a great machine. Personally I think she is an ugly Duckling, but wait until she is in operation...(a very true (orange) swan!)
Cheers, TY


10ett
Posts: 20
Joined: 13 years ago

#30: Post by 10ett »

I will try and put a few videos up here of my cimbali lever in use to give you some help (hopefully):

[youtube]https://youtu.be/Y9NXT_gOb-U[/youtube]