A Chamber Sealer/Packer for Under $100
I’ll fill this out with more photos as I take them. This will ideally become more of a how-to guide, but an open ended one since you can’t really plan for gleaned goods. You can be prepared to find certain types of objects, and that’s why the guide is necessarily verbose. For now, look at the writeup I’ve posted here: http://www.cookingissues.com/forums/viewtopic.php?f=16&t=25&p=904#p904
Pun intended, and facilitated by the failure of the adhesive on a particular bike helmet sticker.
JoresTech 12" Sealer
Guts of the sealer reveal the section that's convenient to hack off so it will fit into the chamber.
Chamber with sealer installed.
Text from CI forum post:
“I know it’s been a while since this thread has been active, but I thought I’d offer some tips based on my experiences with a seriously bootleg vac chamber I’ve been using and tweaking for the past year or so. I’ve been meaning to write about it for almost as long, but I have made tweaks frequently enough that it never quite felt finished. I believe Galen in particular, with his conceptual homebrew contraption that rather resembles mine, will appreciate the dumpster-diven finesse of the rig. The chamber is 12″ in diameter with a 16″ tall Pyrex bell jar, pulls at least 5-10 mmHg (maxes out an analog gauge dial, boils icy water) in 2 mins, will hold that vacuum level overnight when the pump is off, and now has an impulse sealer for vacuum bagging. All for under $100, though like I said, fueled primarily by luck and a passive approach to searching for parts. So keep in mind, this is a guide more than a set of instructions since not all steps are strictly repeatable.
I get my pumps by gutting AC’s that people leave on the curb. Well, actually, my first came from the AC my roommate dropped out of his second story window. My neighbor works with HVAC systems, so I have him drain the refrigerant, and then I cut the compressor out. Before cutting anything take pictures of how it is all wired, and find and remove the starting capacitor. It’ll be a silver cylinder about the size of small tomato paste can with a few sets of prongs on top. The capacitor usually has two sets of tabs, one for the fan and one for the compressor. I anticipate that getting these backwards would cause problems, but I don’t know for sure. If you have any questions about how to wire one up, or any other questions about the whole schebang, leave a message on my blog and I’ll give you a hand.
Don’t hacksaw the copper tubes, though, as the filings can damage the pump if they get sucked in. Use a proper tubing cutter for a clean cut and clean edges. This will also make it easier when you want to attach gas-tight fittings to the copper inlet tube. So far, all of the AC compressors I’ve harvested are made by Rechi. If you get one of those, you can look up the model’s specs here: http://www.rechi.com/en/web_en_products.do
Assuming a Rechi compressor, you’ll see a 1/4″ tube and a 3/8″ tube coming out of it. The 3/8″ is the inlet, which will pull the vacuum, and the 1/4″ is the outlet. Some cotton balls or polyfill stuffed into a small plastic bottle (I used airplane whiskey bottles, because that’s what I had) will make a decent filter when slid over the outlet side. For the inlet side, I use swaged tube fittings like Swagelok, A-lok, Let-Lok, Nupro, or whatever is cheap on eBay (mix and match, they’re all pretty much compatible), to connect the pump to my chamber with copper or steel tubing. I have two valves on my rig. One binary ball valve, and one 3-way ball valve. I use the 2-way on a tee-union to vent the pump to atmosphere before shutting it off. The 3-way is after the 2-way and is used to isolate the chamber and vent the chamber without sucking from the tubing that may have oil contamination. I’m sure this is annoying to visualize, I’ll post pics on my blog since I don’t have any other image host. For now, this will have to do:
Chamber ====(3-way)=====(2 way)===== Pump===Filter
My first chamber was a quart-sized mason jar. It was good for deairing alginate baths or other gels and for vacuum infusing anything that met my whimsy. They’re cheap, ubiquitous, and can withstand the vacuum. I epoxied the vacuum tube into the interchangable jar lid, so I could swap chambers (jars) as necessary. That’s handy when you’re working with hydrocolloids that you want to degas. For reverse spherification, for instance, blend alginate in one jar and your filling in the other, degas both, then work straight from the jars. No sloppy transfer necessary. Top the jars if you want to store them in the fridge for later use. These little chambers are handy and cheap when paired with a good AC pump, but the jars are small. You need something way bigger to house a sealer or to evacuate lidded mason jars for storage of products under vacuum.
While I was toying with the idea of shelling out for a large diameter PVC tube and lexan (because who isn’t going to use alcohol in their chamber? Seriously…) I happened upon something better. A friend was getting rid of a large bell jar from a defunct vacuum chamber and asked me if I could help take it to a recycling center. Instead, I got to take it home. Since it’s a dome of Pyrex, it didn’t require a clear base, so I used a piece of epoxy lab table rescued from a dumpster with a hole drilled for the vacuum tube. Sealing was my main problem then. I was looking for a large piece of silicone to seal, but couldn’t find anything big enough (~13″ diameter to outer edges of glass) at the hardware store, nor did I want to shell out much loot to buy some online in case it didn’t work for me. Instead, I tried plumber’s putty, and that’s what I’ve stuck with for the past ~6 months. I stays pliable, so just make a ring on the table, plop your chamber on it, and pump it down.
The next “chamber” was an inexpensive vacuum distillation setup, but that’s another story. More on that later.
Turning the vacuum chamber into a chamber packer was the next step. The cheapo impulse sealers ($20-50 range) appear to all be identical, despite being sold under different names. Mine’s labelled JoresTech, I think the guts of it say something else though. I got an 8″ sealer figuring it would fit in my 12″ diameter chamber. No dice, it was 12.5″ wide with all the handles and support mumbo jumbo. Luckily, if you dismantle it and remove/relocate the control circuit, you can hacksaw 2.5″ off the one side while leaving the rest of the sealer intact. The lever has a silicone strip that is spring-loaded that you push into the bag/heating wire. In order to activate the sealer, you have to put a fair amount of pressure on the springs. This does seem to create some backpressure in the bag (it inflates a lot), and it’s hard to get a full evacuation of the bag with too much pressure on the lever. It’s hard to get a good seal with too little. You can hit the sweet spot, but it takes some tuning and a sometimes a few tries. Another problem is that when liquids boil, they condense a bit on the bag which can cause sealing troubles. I think I’ll try fishing some thin filament through the base so I can pull the lever down after the final vacuum is achieved. That should at least alleviate the backpressure issue.
Oh, and to deliver power to the sealer, I drilled a hole in the base of the chamber that matched the diameter of an extension cord, fed the cord through, sealed it with some putty, and wired it into an outlet inside the chamber. The sealer plugs into that outlet.”