Friday, June 24, 2011

Easier to Assemble Than an IKEA Bookshelf

When I first started taking this machine apart, I had a slight nagging feeling it would be very difficult to reassemble. I had no idea what I was doing, and therefore took pictures of absolutely everything from multiple angles. As the boiler more or less obstructed everything else interior to the frame, I saved it for inclusion at the end. So, at reassembly, I had a bare black frame and a pile of parts. The boiler, cable, and solenoid mounts I had painted white were the first to reattach to the frame. They were previously riveted on, but I drilled those out and used some screw/nut/washers that I picked up from Home Depot. They snugged in tightly and offered both a removable and aesthetic upgrade to the rivets.

I wanted to see the water level gauge in position, so I attached it next. It used a couple of permanent screw mounts welded to the frame that the washers and nuts tightened against to hold it in place. The next logical part was to add the group heads, which meant it was time to attach the stainless steel front panel to the frame. I made one slight mistake here. For one of the group heads, I had removed the rear threaded double-posts when I did the acid bath soak. The other one was so corroded, I couldn't extract it without damaging the threads, so I just left it in and scrubbed the rust off after it soaked. I didn't realize that one end of the post was slightly longer than the other and that was the end that needed to point out. I mounted it the other way onto the frame which resulted in less post to grip with the nut on the frame side of things, and a slight gap between the group head and the frame on the front side of the machine. After assembling the copper tubing to the group heads, this was less of an issue, and unable to loosen the posts from the group head I just left well enough alone. I added a few copper inlet and outlet pipes to the group heads, and mounted the hot water solenoid assembly on the upper mount.

This was my next mistake which actually occurred much earlier in the project. The assembly attaches by a small bolt that screws into the top of the brass assembly. I over-torqued it and sheared the bolt off inside the assembly. I dutifully went to Home Depot, purchased the smallest Easy-Out bit I could find, drilled out the center of the broken bolt, and promptly broke the higher tensile steel Easy-Out off inside the broken-off bolt. Further attempts to drill it out and re-tap the hole were considered too risky, so I instead drilled 3 additional holes on the mounting bracket, and used zip ties to hold it in place. Inelegant, but effective.

With the group heads securely holding the face plate on, and further bolstered with the inlet and outlet tubes, I incorporated the water inlet tap that mounts under the drip tray and began connecting the tubing and pipes that snake around to the back through the frame cut-outs.The water inlet tap mounts through a couple of holes in the bottom of the frame, but I held off securing it until I had the copper pipes and tubing reconnected. Speaking of tubing, I decided to replace the rubber surgical drain hoses that connected the hot water solenoids at the group heads as well as the drain from the boiler safety valve cap and the water inlet tap. I found it at Home Depot for cheap, but had to use clear vinyl tubing on the group heads since they didn't sell the surgical tubing in a small enough diameter. It may be one of those modifications I'll live to regret, but for now, it looks good and feels snug.

I mounted the pressure gauge and it's cleanly painted mount frame, and continued connecting pipes according to my deconstruction photos. There were a couple of pipe pairs that appeared identical until I tried to connect them to additional pipe connections. After a quick swap, everything was lining up where it should go.
I tried a dry-fit with the boiler in place to make sure all the connections were lining up right and it appeared to be okay. However, once I started tightening down the connections, I discovered the left side group head to boiler lower connection was tightened too far to connect while still retaining a solid seal against the boiler. I took the boiler out, backed the 90 degree connection out and found the very compressed remnants of a green rubber washer. I dug through the tool chest and found one to match the size and add hopefully enough resistance to allow a firm seal with the boiler and the correct angle to connect to the group head. It tightened down perfectly and I connected the group head connection and started adding the additional connecting pipes for the water level gauge, pressure gauge, etc...

The water pump and motor assembly easily dropped into their position next and I secured the 4 rubber cushioned feet of the motor to the frame with the easily identifiable baggie labeled "pump motor mount hardware." I was able to reuse the stainless steel braided hoses, and I connected them to the main inlet connection and the water inlet tap. I snapped some pictures, but quickly realized after reviewing the deconstruction photos that I had them reversed. I swapped them out and all was well.

It was only a matter of minutes before I realized that I was out of copper pipes and that everything on the hydraulic end of things had been put back together. It was almost anti-climatic. I checked and double checked each nut and snugged them tight and decided to call it a day. The last thing left was to install the electrical parts, connect the solenoid plugs, and rewire the power switch box. I still needed to clean up the exterior panels, drip tray and cup trays, but the functional reassembly was nearing completion.

All in all, I think I had this put back together in about 2 hours. I've spent more time on Scandinavian furniture assembly, but it wasn't nearly as fun.

Wednesday, June 22, 2011

Steam Punk, Milk Funk

The front upper cowl of the machine housed the steam knobs, steam wands, and hot water dispenser in addition to the (limited) electronics for the control pads. This had been set to the wayside while tackling the core of the machine, and at this point it was time to give it some attention.

The first thing I noticed was the missing steam wand from the right side. Upon closer inspection, it had been broken off at the ball joint (shown below). A quick parts search and $67 later, I had a new stainless steel wand with a no-burn elbow for repositioning en route. Not sure why, but it appears the left group head gets more attention on these machines and the steam wand gets more use on the right. I'm sure the equipment setup would dictate a lot of which side is easier to pull from and which side is easier to steam milk. If you had the staff, I'm sure both could be done in tandem; as I know for a fact, that beast of a boiler would give you all the hot water and steam you could possibly need with both barrels blasting. Anyway, I made a mental not that upon reassembly, I was going to install it on the left hand side. It was pretty and I wanted to show it off.

The second thing I noticed was the funk and grime that was built up on the underside of the cover and the near total obstruction of the screen for the hot water dispenser with calcium deposits and crud. It wouldn't be until I took apart the steam valves and wands that I would discover the fossilized milk crud that was subdividing apartments in the steam wand ghetto.





It was gross, but at least it was solid and crusty and didn't provide an odor. I disassembled the steam valves and the hot water valve and started snapping pictures so I would be sure to put the parts back together correctly. I still had the citric acid bath I used for the group heads (from hell) so after dis-assembly, I soaked the parts for 10-15 minutes and then scrubbed them with the brass brush. I left the copper and brass in for a bit longer, but I wanted to get the chromed parts out so the acid would clean, but not damage them. The hot water valve looked almost brand new. The before and after photo of the previously crud filled steam valve was also impressive.











There wasn't much to clean on the electronics, and to my dismay there was a chip out of the corner of one of the control pad frames, but for the price of a new one, I was willing to live with some aesthetic degradation. I scrubbed the stainless cowl with some water and Simple Green to remove as much grime and dirt as possible and then gave it the Macguires Step 1 car polish routine I had given the other high gloss stainless parts. It turned out looking nice, but the quick barista-wipe-down-job-around-the-knobs swirls were still there, and like the control panel, I'm willing to live with the "lived in look" of the machine over paying a fabrication shop to electroplate the stainless to bring it back to a flawless mirror shine.
Before
After

















I reassembled the parts onto the cowl and then set it aside until I was ready to install it over the group heads on the frame. At this point, I have soaked, scrubbed, cleaned, and polished all the parts of the machine. The frame is primed, painted and reassembled, and it's time to put this beast back together. Wait patiently (amidst diaper changes, gardening, and home canning) for the next chapter: Easier to Assemble Than an IKEA Bookshelf.

Friday, April 22, 2011

Group Head Gaskets... FROM HELL


Once again, the accurate and impassioned knowledge of the CoffeeGeek and Home Barista community taught me two things.
  1. Group head gaskets should be replaced every 6 months as part of regularly scheduled maintenance.
  2. If group head gaskets have never been replaced on a machine nearly 20 years old, and the rubber composite has been subjected to repeated onslaughts of heat, water, and espresso residue, you will create a fossil.
  3. Fossils are neat when you're 7 years old; they suck when they have integrated themselves into your espresso machine.
I didn't even know how deep this gasket went nor where the gasket started and the espresso residue funk on the underside of the group head ended. The gasket was literally as hard as the surrounding brass. I made my inaugural post to the Home Barista forum to be met with great advice with a slight "oh you noob" undertone. Aside from the newbie chiding, I got my answer on how to remove the gaskets, but the execution was where the real challenge began.

I tried using a spoon like their example showed, and then moved on to the church key (paint can opener). Not getting anything other than frustrated, I ventured out to Lowe's in search of the dentist pick set I heard they had. I finally found them after a lot of searching and store employee assistance, and brought them home to beset upon the gasket fossils of terror. $6 and two bent picks later, I decided to try the wood screw approach. I had to use a power screwdriver on low torque and drilled the screw into the gasket. I pulled on it with some needle-nose pliers and the screw came out bringing with it only as much fossilized rubber as the threads had touched. I tried again and again only to leave the gasket slightly pockmarked as if attacked by a persistent, yet retarded woodpecker. It was time to break out the Dremel 4000.

I had to be very careful not to go too deep or too close to the sides as the group head brass was at risk of being deeply gouged, and aside from aesthetics, it could compromise the seal I was desperately trying to restore. I used the smallest engraving bit I could find, and after securing the group head in a vice padded with towels, I started creating a small crater in the fossilized rubber. Afraid to go too deep, I then began prying with a small bladed screwdriver in the crater and managed to work deep enough that the rubber separated. I tried again a few centimeters back from the split, but I had to use a hammer to gently increase the depth of the blade. It finally popped through and broke out a chunk of the fossilized gasket. I had a brief moment of celebration, and then kept chipping away chunks until about 20% of the gasket was out. With a little leverage, I worked the screwdriver under one of the exposed ends and pryed the rest of it out.

Now knowing the process, I was able to get the second gasket out with much more ease than the first. The shower screens on both were in decent shape, but despite soaking and scrubbing with the brass brush, I couldn't get all the gunk out of the fine mesh. After a quick search on Cafe Parts, I decided to replace them both when I replaced the gaskets. It was definitely worth $7 each.

Now that the hard part was over, I still had the task of cleaning and descaling the group heads. I removed the shower diffuser screws and the pre-infusion chamber as well as all the internal springs and pistons within the group head. I found an exploded view of the E61 group head, and took it down to the most basic parts I felt comfortable doing. I reused some of my original acid bath that I saved in a 2 liter coke bottle, and soaked the brass parts overnight. The chromed group head components I just let soak for 10-15 minutes to prevent problems with flaking or discoloration. As the underside and internals of the group heads are brass and don't have the chrome plating, I turned them upside down and filled them with the citric acid solution to make the residue easier to remove and break up some impressive calcium deposits where the hot water pipe inputs were located. With two group heads, it was pretty easy to get a before and after shot of some of the parts, such as the shower diffuser screws. Black vs. Brass.















After the inverted acid soak, I did the best job I could in scrubbing out the grime inside the group heads with the wire brush and shop rag. My main goal was to remove any remnants of rubber that may have sealed to the brass, and to get the loose espresso reside off to prevent off-tastes when I finally got it up and running. I could have probably spent more time cleaning it up to remove the discoloration, but I think functionally, it is good to go.

The steam wand, steam valves, and hot water dispenser were also cleaned during the group head process, but I think they deserve their own post. Stay tuned for my next post: "Steam Punk, Milk Funk".

Interlude: Shoot often or get screwed

I realized I didn't really cover the organizational aspect of this rebuild in too much detail, so I thought I would made a quick post to comment on how not to turn what was a fun and challenging project, into a junk yard nightmare.

The camera I used was a basic 8MP Canon Powershot 850IS. Nothing too fancy, but it got the job done by photo-documenting the tear down and general construction of the machine. The key was to take a wider shot of the machine from several angles of the parts to be removed, then switch to the macro setting (which looks like a flower) and get detailed shots of each piece you remove in the order you remove it. For the long skinny tubing that disappeared behind the frame wall, I took shots of both connection points one after the other so I would know where to put it back. The great advantage of our wonderful digital camera age is the nearly unlimited quantity of photos you can take with nearly instantaneous feedback on quality and framing of the shot. From inception to completion, I took 613 pictures of this espresso machine and it's assorted parts. They were worth their weight in gold when I began reassembly.

Apart from the symphony of brass nuts and copper tubing performing an aria of mechanical exhibitionism, there are a lot of nuts, bolts, washers, and screws inside a machine this size. Thanks to my pack-ratted-ness and frequency of breaking bicycle parts, I had several small zip lock baggies perfect for storing associated hardware. The snack sized zip lock bags would have also worked, but I was too lazy to go to the store. I also used a cheap plastic fishing lure divider with a snapping lid that I found in my tackle box. This allowed me to either label the bags or drop in the divider a post it note describing what the screws, or bolt assemblies belonged to. When I was reattaching the group heads to the frame, I just grabbed the bag labeled, "group head hardware" and reattached it. Same with the "pump motor mount nuts", and the "power box screws". Organization on the front end will save you screaming and hair pulling on the back end, unless you know... that's your thing.

Next post, I promise... the group head gaskets from hell!

Friday, March 25, 2011

Acid Bath and the Wooly Mammoth

I wanted to figure out a good way to clean up all the brass and copper tubing in an efficient manner that wasn't too corrosive, and would be food-safe-friendly. No one wants to taste Brasso in their Doppio Con Panna (double espresso with whipped cream). I checked the wonderful world wide web and perused the forums of coffeesnob.com.au, coffeegeek.com, and Home-Barista.com to see what was suggested.

The answer, Citric Acid. I think the suggested solution was 2-4 tablespoons of citric acid to one gallon of water. I started surfing Amazon and Ebay for sources after striking out in the local health food stores, and couldn't seem to find anything larger than small containers of 8-12 ounces which cost around $8, and then $4-5 shipping. Then I struck gold on Ebay. $25 for 5 pounds of citric acid. Yeah, it was a little overkill, but that $25 included shipping, and who knew what else I might want to descale in the future. Maybe steam punk would emerge into the mainstream, and I would be the man to polish Jules Verne's time machine. Either way, I may have ended up on a government watch list, or at least a bath-bomb sewing circle for ordering that much in bulk.

I used the top of a large Rubbermaid storage bin and warmed up a gallon pot of water on the stove as heat speeds up the reaction of the acid solution with the metal. I didn't heat all the water, but just enough to raise the temp to around 120 degrees in the container which was already half full with a gallon of cold water. I dissolved about 4-8 tablespoons of citric acid (looks like table salt) into the water and then added the tubing. The reaction was almost instantaneous. The copper started brightening up and losing its dull brown, turning almost pink. The brass started shining through the grime as it fell away. It was pretty amazing. I let it soak for a good 20-30 minutes, occasionally arranging the odd shaped tubing so that it would all get exposed. The soak also broke up most of the mineral deposits inside the tubes. I took all the tubing out rinsing it the best I could, and set it out to dry on a towel on my workbench. I picked up a couple of small pieces and tried some very fine steel wool on it. The shine it brought out was brilliant!

Over the course of the next couple of months when I had a half hour or more to spare, I would sneak down to the garage and shine up the tubing with steel wool. I cleaned it meticulously to the point of shining all 6 sides of each brass nut as well as the top and bottom. There are shiny parts on this machine that will probably never see the light of day again, but I know they're in there.





After finishing up with the brass and copper parts, I decided to clean up the stainless steel back plate and the two stainless steel shims the drip tray is supported from. Again, from the wisdom of the forums, I learned that citric acid is bad for ferrous metals and that the micro-abrasive qualities in car polish would work wonders... unless I wanted to spend the money to have the plates shined professionally by a fabrication shop. (I didn't). While not all the scratches came out, I was able to get the haze removed from the stainless and it looked good enough for my tastes.

I gave the boiler the same citric acid soak treatment as the tubing and used a brass brush to scrub it the best I could. I wanted to really sand it smooth and give it a near mirror finish, but the welds around the connections and seams would not have supported that level of detail and to grind them smooth might reduce the integrity of the boiler. Who wants to have 17 liters of scalding hot water and steam under 15 bars (atmospheres) of pressure explode due to manic cosmetic attention to detail? Not me. I got it clean and confirmed there wasn't any scale inside the boiler which was surprisingly clean. I thought that 5 years of having water sloshing around inside would have been more damaging, but it held up wonderfully.



Now I had a bigger fish to fry before I could start reconstructing. THE GROUP HEADS OF DEATH! I had to get these cleaned up and the fossilized gaskets out before putting much of anything else back onto the frame. But I'll save that for the next post.

Frame the shot

After a rather quick dis-assembly, I ended up with a pile of copper tubing, a box of electrical cables and wiring harnesses, and a dirty frame with a few rust spots on it. I had a box of high gloss black spray paint and grey primer from another "find" I never got around to refinishing. The boiler mounts and electric cable mounts were still riveted to the frame, so I drilled those out to replace with some screws and bolts I picked up for the task.

Before painting, I wanted at the very least to sand down the rust spots to the bare metal to prevent the paint from bubbling. I used 120 grit to start with and worked down to 400. I used the water hose and a brush to scrub the grime and bug crust off the rest and gave it plenty of time to dry. As I was doing this in the winter and the garage wasn't heated, I would put the frame inside to warm up, then take it out and put a coat of primer on, let it dry, and then bring it back inside to warm up again before the next coat. I did the same with the paint. In hindsight, I should have spent more time with prep work and sanded between the primer and paint coats, but considering every bit of the frame would be covered, there was little need for a car show paint job.

I cleaned up the galvanized boiler mounts and other mounts and scrubbed them clean with a brass brush and gave them a good rinse and dry. I spray painted them white just to give it a little more dressed up look when the machine was open, but unfortunately couldn't remove the mount from the pressure switch, so I left it as it was and just cleaned up the grime. Happy to have something clean and restored, I found the hardware for the frame I had labeled and set aside in bags and put it back together. I screwed the big rubber adjustable feet on the bottom and got things leveled up. I also attached the white mounts with the screws and bolts and attached the plastic drain box. Now I had a foundation to build the machine back onto.

Wednesday, March 23, 2011

Always Dive in Head First



When I first brought the machine home, I took the cup warmer tray off the top and looked down inside with very little idea what anything was aside from the obvious boiler, and what specifically I needed to do to get the boiler out to drain the water. Now that I was ready to "do this thing," I located the few screws that held the rear panel on the machine and removed them exposing all the tasty contents of 5 years of abandonment.

The accumulation of steam and condensation served as an oily glue which trapped any dirt, dust, spilled coffee, or grime that might have been floating around in the restaurant. I saw a few Sweet n' Low packets which I thought might have been accidentally dropped into the top of the cup tray until I realized that they were arranged in a nest. A mouse nest, replete with droppings. Mice weren't the only inhabitants as several insect carcasses were found near the power switch unit, which I guess warmed up and made a nice place to live while it was in operation. It was becoming very apparent that this machine was going to need a good cleaning. Even though none of what I could see so far touched the final espresso product, I just couldn't make coffee with a machine I knew was full of mouse turds.
Add Image

Armed with a Canon Powershot 850SD IS digital camera and an assortment of wrenches, I started removing the copper tubing, wiring, and connections inside. I made sure to take photos of the broad area and macro shots of the individual connections so I would have a reference for reassembly. In no time at all, I had the motor, pump, and boiler out and sitting on the work bench accompanied by a pile of copper tubing. All that was left was the frame, the boiler water level gauge, pressure gauge, and wiring connections.















I had about enough for one evening, and with the boiler removed, I did manage to slosh a bit of water out of it. However, at this point I knew I wasn't just going to put it back together. It needed some TLC to restore its former glory, but I had to figure out just how to do that.