Replies to This Discussion

Permalink Reply by Brady on July 28, 2009 at 7:13pm

Explosion, while possible, seems unlikely to me. Overpressure could only happen due to blockage of the tube or extremely cruddy filter... and would probably just pop the upper bowl off. More likely is shattering/imploding when in the suction phase. I'd worry more about burns from the sudden release of boiling hot water on the counter in the customer's vicinity than I would about flying glass. Burn/fire risk from the burner sounds like the biggest concern.

If you are concerned about the possibility of injury, take a couple of precautionary steps to protect customers. Inspect the chambers regularly for cracks or scratches. Don't use the cold towel unless you really know what you are doing and are using the appropriate model. Figure out how to allow full visibility of the process without letting them park their faces next to the glass or get too close to the burner. If you sell them, make sure that they include appropriate instructions to help them use it safely.

I do think it is appropriate for you to be concerned about your customers' safety. Good thinking. I hope this helps. Good luck!

• ▶ Reply

Permalink Reply by Tom Maegdlin on July 28, 2009 at 10:12pm

You are spot on I think. I think I need to implement some kind of precautionary measures for the safety of the customer. I have been injured (not terribly) in every conceivable way behind the machine and I'm not entirely worried about a minor burn here and there. With customers however, even a little burn or splash of hot water whether it is their own fault or not, could be serious trouble for the store.

Although some might view the siphons as just this weeks trend, its truly a great way to get apathetic coffee drinkers excited about different brewing methods. Sometimes if the store quiets down in the mid morning I will start up a siphon and just wait until someone starts to ask about it. Just like when I was at Alterra and we got our Clover, its really great to see someones eyes light up and see that nerdy spark of someone really starting to gain an appreciation for what we are trying to accomplish.

• ▶ Reply

Permalink Reply by Greg Suekoff on July 29, 2009 at 10:57am

Tom! I understand your concern. Tommorrow I am instructing a siphon brewnig class for 15 servers at a Restaurant in Alexandria Va. (Restaurant Eve). They have a "Chef's tasting room" with course style meals and as of Monday, all coffee will be prepared tableside, siphon brewing on a roll up cart. In addition to nailing brew parameters, I am considerng the hazards of a rolling glass brewer with an open flame. BX has a good siphon discussion (started by me) and Coffeed has a great discussion started by Scott Lucey. When I get out there I will bring one of the modified dispersion siphon filters we invented and let you try it out.

Tom Maegdlin said:

You are spot on I think. I think I need to implement some kind of precautionary measures for the safety of the customer. I have been injured (not terribly) in every conceivable way behind the machine and I'm not entirely worried about a minor burn here and there. With customers however, even a little burn or splash of hot water whether it is their own fault or not, could be serious trouble for the store.

Although some might view the siphons as just this weeks trend, its truly a great way to get apathetic coffee drinkers excited about different brewing methods. Sometimes if the store quiets down in the mid morning I will start up a siphon and just wait until someone starts to ask about it. Just like when I was at Alterra and we got our Clover, its really great to see someones eyes light up and see that nerdy spark of someone really starting to gain an appreciation for what we are trying to accomplish.

• ▶ Reply

Permalink Reply by John P on July 29, 2009 at 4:17pm

No chance of exploding if used correctly. Build a small enclosure or glass half-wall to separate the siphon brewers from the customer if you want an extra measure of safety.

• ▶ Reply

Permalink Reply by Tom Maegdlin on July 29, 2009 at 6:25pm

I think this fear of mine stems from I pyrex dish I had explode on me while I was pulling it out of the oven. I grabbed it and as soon as I lifted it out.....crack! Into a thousand pieces.

I know how improbably it is for the pressure to cause and actual explosion. (This could only really happen if the screen somehow created some kind of air-tight seal where the steam had nowhere to go.) I am more worried about some kind of manufacturing flaw that would compromise the structural integrity of the equipment. Like god forbid someone knocking their ice water on it.....and kaboom.

I had a retired 3M engineer tell me that glass manufacturing is like riding a unicycle on a basketball on a treadmill. There are and endless amount of variables. I think that solidified my pyrex PTSD. If there is someone out there who is knowledgeable in glass manufacturing and technology I would really like to hear from you. I need to get some info that will rationalize my phobia.

• ▶ Reply

Permalink Reply by Tom Maegdlin on July 29, 2009 at 6:26pm

I think this fear of mine stems from I pyrex dish I had explode on me while I was pulling it out of the oven. I grabbed it and as soon as I lifted it out.....crack! Into a thousand pieces.

I know how improbably it is for the pressure to cause and actual explosion. (This could only really happen if the screen somehow created some kind of air-tight seal where the steam had nowhere to go.) I am more worried about some kind of manufacturing flaw that would compromise the structural integrity of the equipment. Like god forbid someone knocking their ice water on it.....and kaboom.

I had a retired 3M engineer tell me that glass manufacturing is like riding a unicycle on a basketball on a treadmill. There are and endless amount of variables. I think that solidified my pyrex PTSD. If there is someone out there who is knowledgeable in glass manufacturing and technology I would really like to hear from you. I need to get some info that will rationalize my phobia.

• ▶ Reply

Permalink Reply by Greg Suekoff on August 3, 2009 at 5:48am

Greetings, Tom there are a zillion variations to siphon brewing (and a corresponding zillion posts on said method), and your best gauge is tasting. This restaurant I just trained I suggested use the "passive cooilng" method that uses no cooling medium (wet towel, ice bath etc.) because it produces great coffee, is logistically neater tableside, and allows patrons to see the siphon process. The slightly longer extraction time was adjusted for by way of grind adjustment, and I got the most consisitent times this way. My personal choice is the application of an icy cold wet towel at 50 seconds for a 90 to 120 sec extraction (timer started when coffee is introduced to water in the top chamber, 50-55g of coffee for a 5 cup yama siphon, using a metal filter instead of the cloth). No matter what, I still want to close my eyes and wince when the icy cloth hits the heated glass... BTW, I have a signed lease for Sept 1 arrival in AZ. Looking forward to meeting you and the AZ coffee world...

• ▶ Reply

▶ Reply to Discussion