1980 Olympia Cremina Rebuild - Page 2

Equipment doesn't work? Troubleshooting? If you're handy, members can help.
cccochran

#11: Post by cccochran »

I am totally blown away by how fantastic a job you are doing on this rebuild.
Thanks for sharing your progress with all of the great photos.
Makes my lust for a Cremina all the stronger because of your journey.
Thanks!! (I think)
ps: nice looking stove you have...

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wreckfish (original poster)

#12: Post by wreckfish (original poster) »

Thanks Craig. They are really fun machines to work on and to make espresso with. Hope you find one soon. I went back and checked and it looks like I've taken about 1200 photos during the whole rebuild. They come in really handy when you are trying to put something back together a month later!

-- oh, and the stove is a Wedgewood. Needs a little bit of a cosmetic refresh, but it works great!

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wreckfish (original poster)

#13: Post by wreckfish (original poster) »

The group was in excellent condition, so after cleaning in the ultrasonic cleaner, I set to putting it back together with fresh gaskets. I've struggled mounting circlips to lever pins in the past and despite having purchased some very good circlip pliers have felt that the process was too fiddly and prone to scratching of the chrome. In this case, the chrome was in good shape, so all the more reason to be careful! I contacted HB's forebskm and he made me two sets of new pins - one stainless, the other brass. The pins are like Chicago Screws or "barrel nuts" and eliminate the need for circlips. There has been some discussion here on HB as to which metals are preferred for long term wear and maintenance, so I asked Mike to make them out of the two materials so my bases were covered. These were an excellent investment and I wouldn't hesitate to use them again. They work great and fit with the aesthetic of the machine very well.








* The black rubber cap in the pictures is to protect the head gasket in the group as the theaded part of the piston rod is pushed through.

wsfarrell

#14: Post by wsfarrell »

Great work! Those lever pins are sweet; I have them in a Pavoni and I've found that similar threaded pins come standard on post-1995(ish) Creminas. Circlips should be banned.

I haven't had to deal with asbestos yet on my Cremina rebuilds, but I thought I recalled one of Doug Garrott's videos where he removes it under water so the stuff doesn't get airborne. Could be a way to save $100.

Katoci

#15: Post by Katoci »

100 $ is a bargain to remove that cover by those who did it before, and also take care of the waste. I always wandered what happens with the asbestos removed by peoples at home?

#Wreckfish: did you drill those four little holes to the piston itself? Thought only the new generation comes with them.

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CoffeeBar

#16: Post by CoffeeBar »

Wow, amazing details and tons of pictures. NICE ( good for newbie who needs to rebuild Cremina ) Thank you wreckfish :D

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wreckfish (original poster)

#17: Post by wreckfish (original poster) »

I've seen the video discussion on removing the asbestos in a bucket of water as well as several discussions on HB about it. Personally, it was worth the money to me to have an expert do it and deal with the waste, etc.

I didn't modify the piston. The 4 holes were already there. I'd be curious to know if there are older models without the holes? As I understand it, the holes help to "pressurize" the gasket when it is in movement, making for a tight seal.

Thanks all for the positive comments!

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wreckfish (original poster)

#18: Post by wreckfish (original poster) »

I had all the stainless steel panels and trays electropolished. I was fortunate that there were no significant scratches on the pieces themselves so electropolishing cleaned them up without any additional work. I first learned of the process from a rebuild post from HB's forbeskm and I am very glad I did. It brings the stainless as close to new as possible and is very non-invasive, eliminating the possibility of creating "wows" or waves in the surface that make the polish look inconsistent.



I polished all the bakelite pieces using an auto detailing compound (Meguiar's Ultimate) and a dremel with a polishing wheel. After polishing, I sprayed each piece with Armoral and wiped clean. I have to confess that cleaning up bakelite, even after doing some reading and research, is a bit like voodoo to me. This process seemed to work reasonably well, but by no means brings the pieces to "like new". I used the same treatment on the feet of the machine. One foot showed the only bit of significant damage on the whole machine - it was cracked almost in half, maybe from a small drop? I glued it back together, buffed it with an abrasive pad and then polished it. It came out great and the crack is hardly visible, although I still mounted it at the back of the machine.







After mounting the feet, I reassembled the boiler and mounted it on the frame. Fortunately, this vintage of Cremina used stainless for the boiler bolts, so there was no need to replace those. I swapped out the bolts that attached the boiler to the frame with stainless as these appeared to be steel.







I made a Teflon group to boiler gasket to replace the o-ring that is typically used. The gasket helps with temperature management of the group and is stock on the new Cremina models. A circle cutter and a set of hole punches are key to making these types of gaskets, but in the future I'll try to find a circle cutter with a deeper blade. My Olfa, which I like quite a bit, struggled with the 1/8" thick Teflon.





I reapplied the badges to the machine using double stick tape for exterior applications hoping this would have improved performance around water and heat (Gorilla brand tape). With badges applied and all the components reassembled it was time to put the whole thing together.



Katoci

#19: Post by Katoci »

wreckfish wrote:I've seen the video discussion on removing the asbestos in a bucket of water as well as several discussions on HB about it. Personally, it was worth the money to me to have an expert do it and deal with the waste, etc.

I didn't modify the piston. The 4 holes were already there. I'd be curious to know if there are older models without the holes? As I understand it, the holes help to "pressurize" the gasket when it is in movement, making for a tight seal.

Thanks all for the positive comments!
That's right, that's the goal of them. I'm not sure when did they introduced it, thought it's a fairly new improvement. Unfortunately they tend to be blocked very fast with coffee residue, even if you put aeropress filter paper on the top of the portafilter.
Awesome pictures. Soetimes I think I should do the same with mine, but it's in perfect condition (even aesthetically), and I know it's better to keep it in it's original form.

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spressomon

#20: Post by spressomon »

Wish we had a "like" button ... but since we don't: Great job and a big like as well as kudos for doing it right!
No Espresso = Depresso