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DIY Stir Plate Build

Posted January 25, 2014 By Landis V

I recently posted a link to a DIY stir plate build and needed to get started on my own list to keep track of supplies I have, supplies I need, and where I’m at in that task.  (Note:  As of 2/5, I completed this mostly with equipment I had on hand.)

Part List

List of parts and prices for the build.

  • 120mm Computer case fan
    • Had on hand, typically available for <$5 if you look (techbargains.com, slickdeals.net)
  • Erlenmeyer 2000ml flask
    • (Purchased) Amazon $14.25 (10-Jan-14)
  • Epoxy
    • JB Weld, had on hand, Menards $4.67/Amazon $6.64/Wal Mart $4.67
      • I was surprised to discover that this stuff apparently does actually contain steel.  While affixing the washer to my fan, I observed a small finger of the blended epoxy creeping out from under the washer and towards my magnet.  I’d suggest marking the position of your magnet(s) and centering based on your marks, and not attempting to assemble with the magnets in place.  Otherwise, you may find them epoxied in place!
  • Misc hardware (nuts/bolts/washers for table attachment/standoff)
    • Had on hand.  Used rubber anti-vibration pads that came with the case fan I replaced with the one I had on hand.  I just set the table on top of the fan on the side with the rubber pads protruding and approximately center it.
  • Neodymium/rare earth magnets
  • Stir bars
  • Table to support Erlenmeyer flask above fan
    • Had on hand/made from a ~10″ square piece of plastic, probably about 1/8″ thick, that came from one of those old lights that uses the heat from the bulb to turn an impeller (propeller? should look this up I guess) to cast a rotating image on walls/ceiling through a cellophane medium.
  • Washer (large)
    • Had on hand; if you don’t, less than a buck at the local hardware.
  • 12V Power supply
    • I had one of these on hand that already had a power switch, and had the quick wiring disconnects so I could just tie it right onto the red and black leads from my fan.
  • Potentiometer
    • I picked up a potentiometer from Radio Shack to allow me to control the speed, but I’m not sure I’m going to need it.

Build Process

The build process is more or less as described in the original article I linked to.  I simply centered the large washer on the hub for my case fan and glued it in place with J-B Weld epoxy.  As I noted, J-B Weld does appear to actually contain some steel, so I recommend mounting the washer without having the magnets stuck to it.  Once the epoxy hardens, gently place the magnets on the washer approximately across from each other, spin the fan, and try to balance it as well as possible.  I found that you can place the stir bar across the magnets directly and it helps to visualize how well it will be centered above the fan hub, and ultimately how efficiently and quietly the stir plate will operate.

Below are a few build/post build pictures.

20140125_150610 20140125_150618 20140125_150701 20140125_150725 20140125_150910 20140125_150943

Video of initial test

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Bev-Seal Ultra 235 Notes

Posted January 24, 2014 By Landis V

Reason and Purpose

When I first started to consider the process of fabricating my own keezer, there was a great deal I didn’t know and many components with which I was unfamiliar.  I did know that vinyl tubing has a tendency to influence the mediums it transports, and I wanted to get an idea how much influence “beer line” typically has upon its subject.  It was this threadHBT60380 which first introduced me to Accuflex’s Bev-Seal Ultra Series 235, and from there I was off to the races.  I’ve reached the point where the amount of information I’ve accumulated on this product is worthy of its own post, which will hopefully allow me to take a little bit of noise out of some of my other marginally related posts, instead substituting a link back here.

Description and Characteristics

Bev-Seal Ultra Series 235 tubing hoseThomasnet is a flexible barrier tubing manufactured by Accuflex.  They describe it as a truly flushable dual barrier product allowing quick flavor changes, even for pungent flavors.  It utilizes their trademarked Glas-Flex polymer inner barrier liner, which they claim is “flushable, glass-smooth, non-porous, non-absorbent, non-reactive, taste-free, FDA sanctioned, and NSF51/NSF61 accepted.”Accuflex Kal on the Homebrew Talk forums vouches for these characteristics with independent testing of water left sitting in distribution lines. HBT60380 At the time that thread began, this product was unavailable in 3/16″ ID – which tends to be highly suitable for the short runs commonly found in home built distribution systems – and apparently remained that way for several years.

Forum thread discussing/recommending use of 3/16″ Bev-Seal to reduce foaming, especially on shorter runs and recommendations on how to install.

For 3/16″ ID tubing, 2PSI restriction per foot (necessary for balancing the distribution system), and volume of .18oz per foot (nice to know so I can tell how many ounces of flat beer I might get in a pour after a long rest)  per CHI 24-Jan-14.  At least one source indicates this is far higher than the restriction rate they have found, reporting restriction of .45PSI.

Part number for 3/16″ID series is 235-05620-XX, where XX represents line numbering and/or color on the tubing.

A typical Part Number is 235-08620-XX for a 500 ft. spool of 3/8” size tubing, where “XX” indicates the number to be imprinted (use “00” for unnumbered tubing). The color coding is in the form of  colored strips 120° apart, and number and color coding is as follows: XX = 01 – Blue; 02 – Black; 03 – Red; 04 – Green; 05 – Yellow; 06 – Orange; 07 – Brown; 08 – White; 09 – Pink; 10 – Purple; 11 – Blue; 12 – Black; 13 – Red; 14 – Green; etc. Thomasnet

Footnotes

Accuflex:  Accuflex Bev-Seal Ultra product catalog, retrieved 24-Jan-14, LV
HBT60380: Homebrew Talk forum post documenting testing of a variety of tubing types and their impact on flavor, retrieved 24-Jan-14, LV
Thomasnet: Thomasnet spec sheet for Accuflex products, retrieved 24-Jan-14, LV

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Kegerator/keezer notes for future analysis

Posted January 4, 2014 By Landis V

Note:  This document is a work in progress and will change frequently.  It’s my kegerator scratch pad if you like.

I got at least a portion of the components for my keezer setup this afternoon, along with a 40 gallon boil kettle and several carboys.  Now we can really make beer, as well as some mead and perhaps some wine in the near future as well.  Making a few notes on the buildout for the keezer.  I don’t plan to complete a final build just yet as I’m only doing four pin lock kegs at present, but I don’t want to have to replace core components such as tubing when I upgrade.  I figure it’s best to just start with fresh o-rings and gaskets in the kegs from the outset.

Article that led me to Bev-Seal Ultra 235.
Forum thread discussing/recommending use of 3/16″ Bev-Seal to reduce foaming, especially on shorter runs and recommendations on how to install.

Dip tube insert that allows reduction of serving pressure or line length
http://www.mcmaster.com/#74695a58/=qe6iu6, discovered from thread at http://www.homebrewtalk.com/f35/cure-your-short-hose-troubles-100151/index2.html. Isopropyl alcohol and/or boiling only to clean due to delryn decomposition (highlighted in several posts in the thread).

BYO article on balancing your distribution system.  And another post from a fluid mechanics expert that points the way if I decide to get into the technical details and calculations for accurate determination of hose lengths, though I’m not sure how readily the information about the Bev-Seal Ultra resistance characteristics will be, and as someone else had mentioned it’s also possible that variance/inaccuracy in our regulators could cause a lot of the variations people seem to experience with line lengths.

Adventures in Homebrewing
Complete 4-keg pinlock system (excluding kegs and tank) for $382.99; can add 10# tank for $60. Part/item 4470-7, $382.99

O-rings, 5 sets, post and dip tube, $4.50 shipped – http://www.ebay.com/itm/5-Homebrew-Beer-BALL-or-PIN-LOCK-Cornelius-Keg-Post-Dip-Tube-RED-O-ring-Kits-/151173485689?pt=LH_DefaultDomain_0&hash=item2332a45479

Good deal on set of ten gasket/o-ring kits for ball/pin lock on eBay, added to watch list; somewhat up in the air as I understand pin lock o-rings to be slightly thicker than ball lock.

Freezer Layout and Dimensions for Kegerator/Keezer

Measurements

  • Front to back (outside, corners):  21 11/16″
  • Front to back (outside, middle):  21 5/8″
  • End to end (outside, corners):  41 1/4″
  • End to end (outside, middle):  41 3/16
  • Front to back (inside, inner lip):  16 1/4″
  • End to end (inside, inner lip):  35 13/16″
  • Front to back (inside, outer/upper lip):  17 9/16″
  • End to end (inside, outer/upper lip):  37 1/8″
  • Lip width (inner):  7/16″
  • Lip width (outer/upper):  2″
  • Hump width:  11 1/8″
  • Non-hump width:  24 7/8″
  • Hump depth (top of hump to top of inner lip):  18 11/16″
  • Non-hump depth (bottom of main compartment to top of inner lip):  28 3/4″
  • Body front to back (outside):  21 7/16″
  • Body width end to end (outside):  41″
  • Lid front to back (outside):  21 1/2″
  • Lid width end to end (outside):  41 1/16″
  • Lid height:  1 1/2″
  • Top of lid to top of outer lip:  2″

Open Space Measurements

Measurements of remaining open space with a fill equivalent to six pinlock kegs.

  • Main compartment with 4 kegs, open corner at end (smallest measurement):  5″
  • Main compartment with 4 kegs, open corner next to hump (smallest measurement):  5 1/2″
  • Hump open space at corner with six kegs (approximated), maximum:  6 1/4″ x 7 1/4″
  • Top of keg in main compartment to top of inner collar/lip:  6 1/2″
  • Top of keg on hump to top of outer lip (i.e., minimum collar):  3″

Build Process

Temperature Controller

31-Jan-14

After a false start getting an old work junction box that was only two gang, and both too narrow and too deep for the way I wanted to set up my temperature control unit, I was able to get it mostly put together on Friday (31-Jan-14).  I still didn’t get exactly what I wanted, but I was able to make it work.  Ideally I wanted a faceplate with a rectangular outlet opening on one end and the other two spaces blank.  Unfortunately they didn’t have such a thing at the local big box store, so I got a three gang cover with a rectangle on one end and two regular switch outlets in the other spaces.  I chose this option so I wouldn’t leave any random holes or partial cutouts on the faceplate when I made the hole to mount the controller; its mounting hole will consume both of the switch cutouts completely.

20140131_193850

The keezer temperature controller in a “test fit” configuration. I still need to add a connector for the actual temperature sensor, and I think I’ll get a 1/8″ phono jack and plug to accommodate this.

You may or may not have noticed that the mounting holes for electrical cover plates vary with the component installed behind them.  The mount points in the junction box/gang itself are consistent, as all devices mount into them; this is why I wanted the layout I did, so that the space where I make the cutout for the temperature controller itself will mount directly to the box and the outlet space will attach to the outlet.  They don’t appear to make (or the store didn’t have) a mounting assembly that I could use to adapt the gang box mounting holes to fit the narrower spacing of the light switch holes, so I bought a pair of the cheapest generic light switches they had ($.54 each) and removed the actual switch part, then slightly modified them to make two different types of attachment points (see picture below).

20140131_193907 20140131_193919

6-Feb-14

After picking up a few additional parts from Radio Shack to make the temperature sensor modular/disconnectable, I did some wiring this evening.  I can hear the controller relays kicking, but unfortunately it doesn’t appear to be firing the heating or cooling outlets, so I have some troubleshooting to do.

1/8" stereo jack to allow quick disconnect for temperature sensor. I could have used a mono to match the plug, but Radio Shack didn't have one.

1/8″ stereo jack to allow quick disconnect for temperature sensor. I could have used a mono to match the plug, but Radio Shack didn’t have one.

Soldering the 1/8" male mono plug.

Soldering the 1/8″ male mono plug.

The solder job was better before I had to remove and redo it because I forgot to put the housing on the wires first.

The solder job was better before I had to remove and redo it because I forgot to put the housing on the wires first.

Temperature sensor disconnect in place and wired to the relay.

Temperature sensor disconnect in place and wired to the relay.

Front view of the finished temperature sensor disconnect.

Front view of the finished temperature sensor disconnect.

Temperature sensor disconnect with sensor attached.

Temperature sensor disconnect with sensor attached.

Wiring the outlet. Note the split outlets (the removable bridge between the screws is... removed).

Wiring the outlet. Note the split outlets (the removable bridge between the screws is… removed).

Wiring the outlets into the STC-1000.

Wiring the outlets into the STC-1000.

Hacked together for a test run with a pigtail I keep on hand.

Hacked together for a test run with a pigtail I keep on hand.

Final view of the connections. Unfortunately not working, but I think it's an issue with the controler.

Final view of the connections. Unfortunately not working, but I think it’s an issue with the controler.

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My Stirplate… Cheap and Easy Build… – Home Brew Forums

Posted December 23, 2013 By Landis V

http://www.homebrewtalk.com/f51/my-stirplate-cheap-easy-build-86252/

How to build a stir plate with parts I probably already have on hand.

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Constructing a Backyard Half-Barrel Brewery | MoreBeer

Posted November 19, 2013 By Landis V

http://morebeer.com/articles/building_a_brutus_10_brewery

Quick read, saving in case I ever reach the point where something of this size makes sense.

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Steel Bending Jigs – The Garage Journal Board

Posted November 14, 2013 By Landis V

http://www.garagejournal.com/forum/showthread.php?t=176153

I have had this page open in a browser tab for some time.  Saving in case I find myself with the time and parts to assemble one.  Harbor Freight had a similar model with one additional feature I liked; the “pin” that held the stationary end of the work was actually about a 1″ square stock, which would rotate to pinch the work end against the circular jig as the bend was started.

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Chillers

Posted October 29, 2013 By Landis V

Since my carboys and equipment should arrive between tomorrow and the next day, and Saturday promises to be a brew day, I’m now thinking about chillers.  I’m fairly sure I could borrow one easily, and that is likely to be what I will do.  But at some point I’ll be doing my own brewing in my own garage, and will need a method to rapidly cool wort.  Making a few notes on some of the things I’ve run across while researching the topic so I can find them rapidly when the time comes.

  • Thermodynamics of Chilling
  • Counterflow provides optimal cooling; immersion is simpler and very likely cheaper.  Cleanliness and sterilization is a not insignificant concern in a counterflow chiller.
  • Why?  Reduce dimethyl sulfide which is eliminated from the wort while boiling, but accumulates in the hot wort post-boil until it’s chilled to a level appropriate for fermenting; limit the amount of time wort is in the delicate stage between a sterilizing boil and fermentation with the protection of an airlock and a layer of CO2.
  • Nice, simple build diagram for a basic immersion chiller (maybe use more tubing, had a few thoughts on the subject to increase surface area by possibly incorporating a few verticals.
  • Is there enough variation in temperature to create convection within the wort?  Is there a good way to increase it if so?
  • Chiller built from some thinner diameter tubing, but it doesn’t seem to cool as fast as some of the larger diameter tubing chillers I’ve seen referenced.  May be possible to overcome by pumping from an ice bath?
  • Combination whirlpool/immersion chiller.
  • An article with some of the formulas useful in calculating and improving the efficiency of the heat exchange.
    • Thinner walled tubing is better.  I had been pondering this, but now that I write it down it makes complete sense.  You want the heat to transfer from the wort to the coolant as quickly as possible, and any other medium that the heat has to travel through will impede that.
    • Other thoughts
      • As the wort and cooling medium approach an equilibrium, heat transfer becomes less efficient.  I’m not sure it’s logarithmic, but it’s true that the greater the difference in temperatures, the more efficient the transfer.
      • Only a small amount of the cooling medium within the chiller actually contacts the transfer medium (i.e., copper tube) itself.   Heat will equalize in the cooling medium very quickly due to turbulence.  Does this have an effect that would be relevant to the nominal diameter of the tubing and/or volume to surface area ratio of the tubing?
      • Assuming, I believe accurately, that the temperature of the cooling medium will very rapidly approach the temperature of the wort (i.e., in the first few inches of tubing submerged in the wort), would there not be a benefit to running a split system with several coils like the Hydra in addition to a couple of large volume short length exchangers to cool very rapidly during the initial phase?
      • Flow within the chiller itself – should the cooling medium flow from top-to-bottom or bottom-to-top through the chiller?  Much like a water heater, I would expect the wort temperature to vary from hottest at the surface to coolest at the base, with the exception of a whirlpool chiller which would tend to equalize temperature throughout.  I’m not sure how great this temperature variation would be, though it’s probably realistically too small to even bother considering in a homebrew scenario. (This could also be achieved to some extent by increasing the flow rate of the cooling medium if practical, but may still prove less effective, during the very early phases, over a 20 or 25′ length of tube.)
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