# My Gaggia Classic restore



## Steve_M (May 26, 2018)

Thought I'd share my restoration project here to maybe inspire some others as well as to get some pointers from Gaggia veterans!

I wasn't satisfied with my old Breville BES830XL machine and some searching led me to either the Gaggia Classic or the Rancilio Silvia. After watching a couple of teardown videos on the classic and seeing how mechanically simple the machine was, it was the route I decided to take. I found a used Classic from the late 90's for sale and began the project. To say it wasn't well maintained would be a serious understatement!

I forgot to take a pic of the machine prior to tearing it apart, but the gold coating on the case was in pretty rough shape and while it seems some folks like the gold look of the older models, it wasn't my cup of tea!

Got the machine torn apart here. The bolts holding the boiler to the group head were seized quite badly. Had to use a torch to try and expand the brass on the group head and then I was able to thread out the bolts with some vice grips attached to them.










Here's everything laid out and organized so I don't lose track of things










As you can see, the boiler and group head were in pretty rough shape.










All metal parts ( boiler, group head, OPV, solenoid valve, etc.) got a nice soak in a citric acid bath and I hand sanded the surface of the boiler down to get rid of the pitting.










A little more sanding with some 150, 400 and 800 grit and I got the boiler face cleaned up pretty nice. I also did a bunch of hand sanding inside the boiler










I ordered up an ebay gasket set and and got everything back together.



















Now onto the case. I stripped it down to the bare metal and was contemplating leaving it like this, but there was just too much pitting on the front and in the bottom where the water reservoir and drip tray sit.










Painted it a "stainless steel" tremclad colour. Turned out alright. We'll see how it holds up over time.



















Now onto the next phase. Adding a PID controller. I didn't like the look of the external boxes everyone is using, so I decided to use a small arduino + SSR setup and will keep all of the components inside other than a small OLED screen that will sit outside the case.

Here's a shot of the boiler with a thermocouple with M4 threads that screwed into the old coffee thermostat location.










Testing out the solid state relay with an arduino board I had already made up for another project.










This is what the current arduino board looks like. It's not the final state either, but it's much smaller.










As is stands right now, I've got the machine up and running and have been using it daily for about a week and it's been running great. I need to finished up the arduino bit and get it all mounted inside. The PID control is working quite well. I also ordered up a bottomless portafilter from ebay and splurged on a nice VST 18 gram basket.










Additional things I have planned. Not all of them are high priority:


Create multiple pages for the OLED display and cycle through them

Read the status of the steam switch to crank up the boiler setpoint for the steam wand.

Either add an analog pressure gauge to the front of the machine or use a pressure transducer and use the MCU and OLED to display it

Read the status of the brew switch so that the OLED displays a second timer to time the shots

Add a second SSR to PWM control the water pump to add a pre-infusion stage


The code running on the arduino is here.

I'll keep the thread updated as things progress.


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## El carajillo (Mar 16, 2013)

Nice to see the effort you have put in to restore your machine:good:


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## SurferBoi (Jun 11, 2018)

Great work! Maybe now I'll find the courage to take a part my Classic for a good clean


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## El carajillo (Mar 16, 2013)

SurferBoi said:


> Great work! Maybe now I'll find the courage to take a part my Classic for a good clean


Go ahead , you know you want to and you can buy tools


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## koi (Oct 12, 2014)

Love how simple the classic is on the inside, get a good understanding of how coffee machines work.


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## Steve_M (May 26, 2018)

The simplicity of the machine is really what attracted me to it. Boiler, pump, OPV and 3 way solenoid. Even the choice of using a neon lamp as the brew light indicator is really neat, allowing the lamp to be lit when the boiler isn't receiving power. It allows me to keep using the brew light even when using the solid state relay. You can approximate the temp even without an external readout by looking at how much the brew light is pulsing off.


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## Jollybean (May 19, 2013)

Great refurb job. That should keep you going for years.


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## jjstorgaard (Jan 19, 2019)

Very impressive work. Did you simply hand-sand it? And did you use a particular kind of paint? I've been thinking about repainting my Classic, but most things I can find on the internet about it recommend sand-blasting and powdercoating it.


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## Wilko 4473 (Dec 27, 2018)

Great job. I'm in the process of doing g a restore. Just purchased a 2006 gaggia classic. Was going to give it a go first but the info from the seller was that it took a long time to heat up. It didn't look at all clean so decided I would do a completestrip and rebuild. I've got it all apart and labeled up + took pics for the reassembly. Only issues so far are I can't get the shower plate out (I'll try the longer bolt in the middle hole tomorrow) and the 4 bolts that hold the boiler to the group head are seized on. I've managed to undo 1 out of the 4.


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## Steve_M (May 26, 2018)

jjstorgaard said:


> Very impressive work. Did you simply hand-sand it? And did you use a particular kind of paint? I've been thinking about repainting my Classic, but most things I can find on the internet about it recommend sand-blasting and powdercoating it.


I started with sanding and then used the scotchbrite pads on my die grinder for quicker removal. I used a wire wheel to get into some of the pitted spots. Paint was multiple coats of primer and paint plus a few coats of a matte clear coat.


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## Steve_M (May 26, 2018)

Wilko 4473 said:


> Great job. I'm in the process of doing g a restore. Just purchased a 2006 gaggia classic. Was going to give it a go first but the info from the seller was that it took a long time to heat up. It didn't look at all clean so decided I would do a completestrip and rebuild. I've got it all apart and labeled up + took pics for the reassembly. Only issues so far are I can't get the shower plate out (I'll try the longer bolt in the middle hole tomorrow) and the 4 bolts that hold the boiler to the group head are seized on. I've managed to undo 1 out of the 4.


Not sure if you've left the big rubber gasket in that surrounds the shower plate, but you'll need to remove that to get the shower plate off.

I used a bit of heat to remove the bolts that hold the boiler to the group head. Make sure you've got a good fitting hex driver so that you can wiggle the screw without stripping it.


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## Wilko 4473 (Dec 27, 2018)

I haven't removed that gasket yet. It's being a pain to remove even that, let alone the shower plate! Think I will butcher it tomorrow as all seals & gaskets will get replaced. As will the plate. It didn't look in good shape at all. How much heat did you use on those boiler bolts? Did you use bottles? Hoping to have a good go at getting the last bits off tomorrow so I can give it a good clean. By the time I'm done it'll probably be as much as it would to just buy a decent 2nd hand machine but at least this way I'm learning a lot about it, & I've not pulled a single shot from it as yet!!


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## mvogler (Mar 2, 2019)

Awesome job! I have a similar project planed for the next few weeks. Was your case painted? Mine is painted black and I really love the stainless steel look. Any suggestions on how to remove the paint?


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## ashcroc (Oct 28, 2016)

mvogler said:


> Awesome job! I have a similar project planed for the next few weeks. Was your case painted? Mine is painted black and I really love the stainless steel look. Any suggestions on how to remove the paint?


It all depends on what your paint is hiding. There are companies like A.M.Philpot who could hard chrome it for a price.


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## Bullit (Mar 7, 2019)

Fantastic job on the restore


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## Andy6 (Jan 8, 2018)

@Steve_M I hope you're well. Thanks for a really interesting thread, it has inspired me to do something similar so I've just bought a gold Gaggia Classic. It has quite a lot of rust/pitted metal so I think I will sand it down and repaint because of your thread. I was wondering how your painted version has held up over time? I've not owned a Gaggia before but figured I would have a go at taking it apart and restoring it. The insides, group head etc are all in good condition but I will take the boiler apart to check for limescale/rust etc. If you have any other thoughts about what you might have done differently it would be great to hear them please. Thanks


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## Steve_M (May 26, 2018)

Hi @Andy6 the paint did hold up fine while I was using it. I did put 3 or 4 coats of clear coat on it. I've since replaced the machine with an early 2000s classic that I also refurbed. I still keep the painted machine around as a spare.

I would have preferred to have the case powder coated instead of painting it, but I couldn't find anyone in my local area that was able to do it.


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## Andy6 (Jan 8, 2018)

Thanks @Steve_M that's helpful to know, appreciate the reply.


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