Sunbeam Coffeemaster C30C

[EricBNC]

I have an extra bottom kettle - I will test it out and let you know if it works correctly. Us NC C30 Vac Pot enthusiasts need to look out for each other.

[bigbells]

Another Tarheel! We're holding our own against the contingent from the land of Da Bears.
I have my doubts that the problem is with the bowl I'm using but will experiment with my other usable bowl and then report back.
Happy Thanksgiving Day, USA!

[bigbells]

Made a pot using bowl (lower pot) number 2. Results: completely acceptable. There must, for some reason, be a slight vacuum leak when I use bowl number 1, causing the brew temperature to be too high. I was fooled into thinking there was no leak by the fact that the drawdown is so quick and complete. I can't visually find any reason for bowl number 1 to be leaking vacuum. I use the same funnel with both bowls.

[bigbells]

When reporting on the too-hot brewing with bowl number 1, I omitted details which I thought were irrelevant. It turns out those details are important.

Bowl number 2, which is functioning properly, is the one I'd been using until I decided to try bowl number 1 because it has a slightly larger capacity than bowl number 2. Bowl number 2 had started to pull up a small amount of water into the siphon too early. I mistakenly thought this was because of bowl number 2's slightly smaller capacity, which is only a couple ounces less than bowl number 1. I didn't want the grounds to get wet early with water that was not yet at brewing temperature.

Then, when the same problem occurred with bowl number 1, I realized that it was due to the need for more spring tension to hold the filter assembly in place. I remedied that problem by stretching the spring, but forgot all about the fact that this would solve the problem with bowl number 2 as well.

When bowl number 1 had a faster drawdown than bowl number 2, I figured that bowl number 1 had a superior vacuum seal. This was a mistaken judgement. It is now my opinion that bowl number 1 has a leaking seal which contributed to a faster drawdown for reasons that I think I understand but which are to the best of my knowledge unimportant. The leaking seal is also the reason that the brew temperature was too high.

Resuming the use of bowl number 2, making sure that I stretch the spring prior to each use, is giving great results, and the siphon is remaining dry until the moment when all the water starts to rise from the bowl at proper temperature. I particularly enjoy that I am able to use a quite fine grind (10 setting with my Baratza Encore) and get great and efficient extraction in the relatively short brew time with insignificant or zero sediment. I have increased my grounds-per-pot to 50 grams, which for me is strong coffee. The amount that I brew is 38 to 42 ounces, to which I then add cold tap water to equal approximately 50 ounces, right up near the very brim of my 52 oz Aladdin mug.

[EricBNC]

Glad to hear you have the C30 brewing to spec now - these are neat machines. I wonder if vac brewing will ever make enough of a comeback for some manufacturer to jump back in to this type of production? I bet these would not be cheap - it would take a couple pounds of nickel plated copper just to begin recreating one of these.

I think they sold for $15 - $20 back when they were new, so the equivalent of $150 - $200 today before taking into account current material costs that exceed the typical inflation rate.

[bigbells]

I had settled into a habit which had quickly become unthinking: using the Baratza Encore grind setting of "12" for my vacpot brews with the C30C. I had tried a setting as fine as "9" once or twice before and decided that the grind was too fine. In retrospect, I think I had no good reason to move back up to a coarser setting. I probably made a pot from insufficiently rested roast and wrongly blamed the unrested flavor on the grind size. Then there were a couple of pots that had some sediment, which in my mind I may have blamed on grind size but which in reality were due first to a twisted portion of the filter screen gasket and then to there not being enough spring tension holding the filter in place. I remedied that gasket problem, then the spring tension problem, but still didn't try to grind finer. Additionally, a different bowl that I briefly tried caused a small vacuum leak between the bowl and the funnel which I could not detect at first, and the drawdown was faster, causing further delay in identifying that there was a vacuum leak because I saw no reason to equate "faster drawdown" with "vacuum leak". In some unknown mental process I credited larger grind size with faster drawdown even though the faster drawdown was caused (counterintuitively) by the vacuum leak. Last but not least, there's the distinct possibility that a 2nd opinion has influenced my assessment of brew quality.

Over the weekend, a desire to make a stronger brew for my brother shook me out of the "12 size grind" habit and I used "8" for 3 pots. There is a pause in the drawdown process, after about 2/3 of the liquid has returned to the bowl from the funnel, but this pause has always existed regardless of how fine or how coarse I grind. Results with the smaller grind size were excellent, causing me to think: why stop there?

I'm currently enjoying greatly a pot made with grind setting of "6", despite the fact that the coffee was roasted only 10 hours ago. Hmmm... no sign of overextraction or sediment. In fact, I'm thinking if this Brazil Fazenda do Sertao Lot 50 is this good after 10 hours, how great is it going to be after more rest?

Guess I'll try a grind setting of "5" for the next pot. Lessons to be learned?: I dunno. Knowledge to absorb?: only if you find some. My observations are strictly empirical, subject to change, and as you can see I sometimes draw incorrect conclusions from those observations.

I'll mention once again that I really love the 50+ year old C30C vacpot, the effectiveness of its very fine mesh metal screen permanent filter, its fully automated process and the metal construction which obviates any worries about implosion or breakage.

[LittleB]

Thank you for sharing all of this, Dave! I tried a Cory vac pot and loved the taste so much that I went ahead and bought a Sunbeam C30C. It didn't seem to work right and I bought a 2nd one. That one has other issues so I decided to buy a replacement seal from dayseal.

I tried installing it with the metal band like on the original and destroyed the thing. The directions are not clear about what to do with the band once removed. To Lee's credit, he offered to replace it for half price if I return the ruined one.

How do you deal with the freshly ground coffee blooming in the upper pot? Mine spews out the top before it can calm down.

[bigbells]

The excessive bubbling and the less-than-perfect seal are related. Should be less of an issue once you get the better seal, and until then the water is probably a little too hot for optimal brewing. When this was happening with one of the set-ups I was using, I unscientifically but effectively poured small amounts of cold tap water into the funnel after the water starting rising to keep the water temperature down a little.

I stir with a spoon when the water rises to get any floating grounds saturated. Using the lid on the top will help, and/or brewing a slightly smaller amount. Through trial and error I've found that my particular bowl/funnel combination has a maximum useful capacity of 1125 ml. If I use any more water than that, a small amount rises too early into the funnel, pre-wetting the grounds, which I don't wish to do because the water is not yet up to temperature.

[LittleB]

Thank you Dave, I'll keep that in mind.

I have a C30C coming that was supposedly never used so it will be interesting to compare how it works with the other two. I want to know what the dimensions of the sealing gasket is. I think the after market one sold by dayseal are too thick which would cause the tube to not be at the optimal distance from the bottom of the pot. Sunbeam's service manual says that if the distance is too short it will switch off too soon and if it is too far away it will cause violent bubbling. The thicker seal would make the tube higher than spec so maybe that is why the bubbling is so bad.

Do yours bubble after the switch trips to low? Both of mine do after 1 minute of switching. The vacuum starts from 1 to 1.5 minutes after the secondary bubbling. Is this 'normal'?

[bigbells]

Everything can be somewhat finicky. I manually switch to low 10 to 15 seconds after all the water has risen into the funnel, or manually hold the switch on the high setting if the machine switches to low before then.

From comments that I've read from others, I tend to agree with you that the Dayseal gasket is not a perfect fit. I have not personally bought one.

Try manually switching to low, or better yet, pulling the plug, within a few seconds of the time that all the water has come up into the funnel. My guess, though, is that the water is already too hot for optimal brewing, and would be helped by the addition of some cooler water as the water rises and shortly thereafter.

For a while, my unit was working perfectly, without being attended or fiddled with. That only lasted for about 40 consecutive pots. It seems that either the thermostat settings don't stay put, or that when the vacuum seal becomes less effective the water rises at too high a temperature.

Currently, my unit does do the secondary bubbling after switching to low, but only for about 15 seconds. However, my unit now wants to switch to low before all the water has risen so I have to manually hold it in the high position to get all the water up. My suspicion is that this anomaly is being caused by a leaking seal.

I wish you the best of luck with your never-used C30C. Again based on experiences I've read about that others have had, the seal could still be imperfect due simply to aging.