Look Ma no fans Coffin Cooler

Look Ma no fans Coffin Cooler
This is a work in progress and I will post pics as go. I already have a two keg kegerator that uses copper pipe extended from the fridge to just below the taps. For me this works great for eliminating first pour foam, but I needed more variety. So I am building a similar but larger version. The heart of the build is a Kenmore 15cf chest freezer off of Craigslist for free. It’s quite old but that’s why it was free.
I have already changed plans several times so feel free to post suggestions and I may change things again. I will use pieces of copper baseboard element for more surface area that will be attached to the underside of the lid. Copper extensions will go up into the coffin. The baseboard element will be filled with water and the beer line will pass through the copper pipe through a compression fitting. I thought surrounding the beer line with cold water would be more efficient than cold air. Originally I was going to use the vinyl tubing and push it through the compression fitting but I may go with some SS tubing instead for better conduction. The original plan was to hold it 0together with “Cross” fittings but due to availability and price I had to switch to “Tee” fittings. The scan of my drawing came out terrible since it was done in pencil and I had darken it up quite a bit but you can get the point.




On a side note I have wondered why people use 2x4s to construct the walls around keezers, it seems like overkill to me. I had some extra strapping lying around and it seems to be strong enough, we’ll see.

The drawing does help clarify what you were telling me for what you have planned... Will be interested in seeing how it comes out.

My lid is heavy enough without adding more metal weight to it. Fans and 12volt transformer are light and cheap. Guess if you only have a couple of taps it would be ok,

subscribbled

I worked a little on it yesterday, cutting up the heating element, figuring the spacing and test fitting. No soldering was done. Here is what I did with a few pics.

The aluminum fins on the element are just pressed fit onto the 3/4" copper pipe. After measuring I separated the fins where I was going to cut just enough to slip a hacksaw in between them and cut.



I then removed just enough fins so that I have enough room to solder the Tees on. One side of the fins is flush but the other has four triangular shaped prongs that grip the pipe. Since the area of the pipe that is finned will only be around six inches I tried to keep as many of the fins as possible. I moved the last fin to the end of the pipe and bent the four prongs up out of the way and pushed the fin back with the rest.







I then test fit the pieces together. There will be three of the cooling elements in the keezer. Two will be connected to two taps each and the third will only be connected to the middle tap. When its done I will take temps of all of the taps and see if there is any temperature difference between single and double taps. The plastic compression fittings are similar to the shark bite ones. The 1/4" OD vinyl tubing squeezes perfectly through the fitting but I will try some SS tubing when it arrives.



Including the fittings the length of each element will only be around eight inches. I am guessing that the short length of the elements will be sufficient to cool the taps due to the surface area of the fins, cooling liquid and the relatively short vertical run of the pipe. If I need more cooling later I can always increase the length of the element.

The only issue I see so far is that it may be difficult soldering the Tees on due to how close the fins are.

For those concerned with how heavy this will be I will weigh each element when done and let you know the number is. I would guess that it will be right around the weight of one tile that people are attaching to their lids.

I ran into two issues today first was the soldering of the cooling elements. It seems the fins work too good and were wicking away the heat making it difficult to solder than the rest of the pieces. Originally I had the fitting touching the last fin but without additional space the solder would not flow between the pipe and fitting. I had to pull a couple more fins off of each end of each element so the solder would flow.

In this pic you can just see some of the white oak (top right) I bought today for $1 bf. For those in Massachusetts if you need rough cut lumber he in on CL in Barre, Ma great guy and great prices. It was a bit of a ride for me but worth it. His select wood was $2 bf!


The second issue was the plastic compression fitting. I know I was able to push 1/4" vinyl tubing completely through the fitting while in the store. Well it turns out that you can push the tubing into the fitting but the hole then narrows preventing the hose from passing completely through. I was a bit frustrated and drilled out the narrower side of the fitting with a 1/4" bit and it worked. I had to be careful not to go too far and damage the o-ring. What I did was chucked the drill bit in my drill and turned the fitting by hand, it ended up working quite well. Sorry no pics of the fitting before it met the drill.





I figure I will keep a couple of taps with the vinyl hose and the rest with the SS to record the difference in temp.

I only had a little time today to work on this so not much was accomplished. I cut part of the underside of the lid removing the protruding part which will be replaced with a sturdier section of plywood. This will give me a flat surface to mount the cooling pieces to. I also tested for leaks and weighed each cooling element without water in it. I took a couple of quick pics while weighing them. The double armed ones held 6 oz of water each while the single held 4 oz.

The first double armed cooling element weighed 1lb 4.2 oz



The second one weighed 1lb 4.4 oz



The single armed one weighed 12.6 oz

Here is a pic of the copper cooling lines mounted to the keezer top.





My initial idea was to make this keezer look like an old chest with a cask on top of it. The cask would open like a clam and inside would be a five tap coffin with low profile tap handles. Well I found a cask and after taking it apart, reassembling it several times and dealing with the small interior, I gave up. I was so focused on the tap spacing and getting it just right when I realized that the coffin would not fit inside the cask.



On to plan B, the cask was still going to be on top of the keezer but now the taps would be mounted directly to the cask. It would look similar to one ones sold online for $1500 but my cask would be horizontal.



After bolting is back together yet again I realized that the vertical copper lines did not have to be exact and could be crowded together a bit.
Back to plan A, took the cask apart again and mounted the hinge. I had to tweek it a bit because once you take these things apart they never seem to want to line back up again.

Great idea with the cask. Looking good.

Eager to see what temps you get with the conductive cooling...

Fins...never thought of that!

Instead of soldering the fins on completely, what about using thermal paste to fill the gaps? e.g. arctic silver

shroomzofdoom: Thanks, while the cask idea was mine I cant claim credit for the fins. The idea actually came from someone I work with that used to be a plumber.

weirdboy: The fins are not soldered on, just the copper fittings. From what I have read, the higher the thermal conductivity numbers are the better the temp transfer.

Thermal grease would be messy and has a thermal conductive number of less than 10 while the copper and aluminum numbers are in the hundreds. I'm not sure which gaps your talking about but completely filling in the gaps between each fin would decrease my surface area and would inhibit temp transfer.

Using a very small amount to fill in any minute air gaps where the aluminum fins are pressed onto the copper would help but its not worth the time and effort for me.

purplehaze said:

shroomzofdoom: Thanks, while the cask idea was mine I cant claim credit for the fins. The idea actually came from someone I work with that used to be a plumber.

weirdboy: The fins are not soldered on, just the copper fittings. From what I have read, the higher the thermal conductivity numbers are the better the temp transfer.

Thermal grease would be messy and has a thermal conductive number of less than 10 while the copper and aluminum numbers are in the hundreds. I'm not sure which gaps your talking about but completely filling in the gaps between each fin would decrease my surface area and would inhibit temp transfer.

Using a very small amount to fill in any minute air gaps where the aluminum fins are pressed onto the copper would help but its not worth the time and effort for me.

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I think he was talking about using arctic silver thermal paste or arctic silver thermal epoxy to attach the fins the the tubing. the thermal numbers of arctic silver are some of the best in the computer business and used to fill the microscopic gaps in the metal between the heatsink and CPU surface. if you used it to attach the fins to the tube your thermal transfer would increase because there's air gaps in there that you don't see. as far as it being messy, if you use to much then yes, if you use a thin layer which is the way it should be used, then there will be no mess. if you use the thermal epoxy then there would be no mess as well.

The AS Ceramic compound kicks-ass for processor heat sinks... Where thermal transmission is critical, they are top shelf... Even though I no longer build computers, I still have some on hand. I used it when I replaced/upgraded the processors in my tower o' power...

Golddiggie & Mysticmead

I have never used thermal paste and I'm sure it works well on CPU heat sinks. However for this application I'm not sure the end result would be worth the effort.

Sure I could remove each fin and apply the thermal paste or thermal epoxy but the fins are press fit onto the copper pipe. The few I did remove and reinstalled were loose afterward, making the air gaps between the fin and pipe bigger. Not to mention how the heat of soldering the fittings on would affect the grease/epoxy.

Made some progress today.

The temp controller finally came in the mail and is now wired up. The controller is built into the cask support. Hopefully I can fit the single regulator in the space underneath it, if not I can always enlarge it.





I then had to reconfigure the vertical copper lines and crowd them a bit so they would fit into the coffin which will be in the cask.



I took apart some of the framing of 2 X 4's and cut them to 1.5 X 1.5 to make sure I had enough oak to cover the outside. I installed the oak and added some of angle iron to see how it would look. I think I am going to continue with it.

Are you planning to insulate the copper lines inside the cask?

Yes, I will probably fill the coffin cavity mostly with expanding foam. The coffin lower front is open right now but I plan on filling it in with some kind of basket weave pattern in spalted cherry.



The coffin is made out of black cherry that I cut from a log a while back. Inside the cask looks like a tight fit with the coffin and it is. I plan on attaching the front of the cask support to the cask so as it opens it pulls this piece up and out of the way of the drip tray. I thought I would have more room but I will only have four to five inches available for tap handles. This of course eliminates every one I have made so far.



I attached the oak to the top and have to adjust slightly for fit but its getting closer to being finished. After doing a test fit of the coffin and cask I have to again rearrange the copper lines for better function.

All the little details eat up a lot of time even though I had a plan I am still changing things as I go. The cold weather dosen't help and limits the time I can spend in my unheated shop. Also the cold makes the glue curing time longer.

I attached some of the metal straps and angle iron to the top. It's not all bolted together but you get the idea. Yes the lid is heavy so I will be looking into some lift assist shocks.



Here is the coffin with the decorative inlay. The top is not attached and I have yet to add a finish to the wood, attach the tap lines, insulate, sand, etc.





The basket weave pattern is made up of some spalted cherry that has an interesting blueish color. I also needed a contrasting colored wood to fill in the 1/4" square pieces. I had a small piece of Irish bog oak which is a couple thousand years old that I cut up. I had to cut each piece by hand with a utility knife. Its not finish sanded yet, you can see some of the glue on the front. Right now the inlay is only press fit into the cavity for the picture. Once the drip tray arrives in the mail I can button this up and finish it.

wow this is really dumb...send it to me to scrap and restart over

BEAUTIFUL! any thoughts about making the freezer a huge cask? i mean at least the top, front and sides. This is inspiring, subscribed.

extra_medium and ekjohns, thanks for the comments.

Someone on this forum did successfully make a kegerator out of a large barrel. Using the guts from a fridge he was able to mount everything inside with a fan on the bottom. I think it held two corny kegs and looked great. To make one big enough to cover a 15 cf freezer would be quite the undertaking, not to mention out of my league.

UPDATE: The going has been slow but I made some progress as well as some mistakes. I mounted three stainless lines and two vinyl lines through the copper pipe. I then filled the copper pipe with RV antifreeze and capped them with the compression fittings. The two using the vinyl tubing were a very tight fit and would not squeeze past the locking clip. I dont know why they would no fit maybe I will try some keg lube. I ended up taking a shortcut and removed the locking clip. It worked with no leaks.





A couple days later I checked and there was a small puddle of pink antifreeze on the floor. Tomorrow I will drain the one that leaked and reinstall the clips to see it that will stop the leak.



All of the metal is DONE! I am burt out and refuse to put any more on at this time. All of the angle iron and strapping was cut with an grinder and cutoff wheel. The fortyfive dregree angles were a pain, one turned out pretty close while the other one has a bit of a gap. I might have a buddy of mine come over and weld the corners, covering up my mistake.





Second issue is the drip tray I ordered was too long making it necessary to cut into the cask support. I will build out the sides with some trim to cover the protrusion. Finally got the cherry coffin coated with some poly. Nothing is permanently mounted yet but once I fix the antifreeze leak that will change. The inlay piece is upside down in the pic.

Is that the barproducts.com drip tray? If so--and at that price--it makes sense to design the entire keezer around that! Curious though how you get it out to clean it? Assuming it just slides forward and away?

Also, any temp tests of the coffin and keezer? That's the part I am waiting for.

EDIT--Forgot to add; looking very good! Love the design!

Is that the barproducts.com drip tray? If so--and at that price--it makes sense to design the entire keezer around that!

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LOL Yes it is the Barproducts drip tray and no I didn't design the keezer around it. Actually the drip try was the last piece I ordered. I knew which ever one I bought I would have to modify things to make it work.

Also, any temp tests of the coffin and keezer? That's the part I am waiting for.

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Including me. I planned on using expanding foam but that would lock everything in place and prevent future disassembly. Temporarily I will use just some fiberglass along with pipe insulation until I get the bugs out.

Hopefully I can fix the leak just by reinstalling the locking clips. If not it would appear that the vinyl tube is just too pliable to seal correctly.

Right now I am looking for a cheap and accurate thermometer, maybe one with two probes.

One other thing, how did everyone else plug up the drain in the freezer floor, mine did not come with any kind of plug. I may have just install a rubber cork inside and outside.

purplehaze said:

One other thing, how did everyone else plug up the drain in the freezer floor, mine did not come with any kind of plug. I may have just install a rubber cork inside and outside.

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Mine actually has a threaded plug on the face-I can unscrew and drain from there, but I never do. Cool design but I panelled over it.

To clean the freezer (once a year) I just unplug it to let it defrost then throw rags in the bottom to sop up the water, then clean with Oxiclean. I bought rubber floor mats from Lowes and cut to fit the bottom. They have 1/2" rubber nubs which keep the kegs from freezing to the floor.

I've also seen guys hook up PVC elbow and pipe to route the drain and make it easier to clean.

If you pick up line stiffeners it will stop the leak caused by the flex line. You can get them at the chi company. I also think that Lowes has them. it is just abit of plastic that goes in the end of the tube and makes it stiff.

shroomzofdoom, I think your way would be easiest at this point so I will just fill the hole with some expanding foam and call it a day.

crazyirishman34, that is a good idea but I don't think the inserts would work in this case. The ID of the hose is 3/16" so I would hesitate to make it any smaller with an insert. Plus the insert would have to be pushed about two feet down the hose to line up with the bottom compression fitting. It appears that I fixed the leak on the fittings that have the vinyl line by reinserting the locking clips.

Isn't it important to keep the faucets cold also? We have long line setup at our family vacation place. And when the glycol is on and running the faucets get pretty cold. Not to the point of freezing but on a muggy day they do get condensation on them.

Yes I have some preliminary temp RESULTS.

I dont have much time but I will post what I have.

At the moment I have only two of the vinyl lines hooked, no SS yet. There is no insulation covering the few inches of vinyl line above the copper connecting to the shanks. Hope that makes sense, I will post some pics tomorrow.

E-bay temp controller with probe in a large mug of water on the compressor hump.
Taylor digital therm from HD +/- 1 degree

Air temp in shed = 40.7 F
E-bay temp controller = 2.5 C / 37 F
Taylor probe- compressor hump water test = 36.5 F
Taylor probe- First pour of beer in glass = 38 F

I always thought that the pH of fermented beer was such that you didn't want it in contact with copper. Am I way off base?

I always thought that the pH of fermented beer was such that you didn't want it in contact with copper. Am I way off base?

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I have heard that also. Look at my first pic specifically the drawing, it may explain it better than I can with words.

Basically the copper is just to transfer the cold from the freezer up to the beer taps. The copper also holds the RV antifreeze and the SS or vinyl lines pass through it. The finished beer never comes into contact with the copper it travels through the SS and or vinyl.

Ahh - my bad!

Learned a few things while installing the faucets. My old kegerator tower had grooved locking collars on the faucets and I was able to hand tighten them with no leaks. On the new perlicks the collars are smooth so after hand tightening I had Niagara Falls. I did not have a faucet wrench and the local HBS were out of stock. I did not want to wait a week for a delivery so I improvised. I took a grinder to an old flat open ended wrench and made my own. Its not pretty but it works.





Then I had issues with the hoses coming off the SS tube because there is no barb on it. I ended up losing about a quart of Porter. The worm clamps I picked up are not small enough to fit over the 3/16" tubing. I may try and slip the smaller tubing into a piece of 1/4" tubing for a collar that the clamps will fit.

Crazyirishman34, I was in the process of posting and missed your post

Isn't it important to keep the faucets cold also? We have long line setup at our family vacation place. And when the glycol is on and running the faucets get pretty cold. Not to the point of freezing but on a muggy day they do get condensation on them.

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I'm not sure how important it is to keep the faucets cold. I did not plan for that in my build other than to insulate the the shanks. I would assume they would leach some of the cold away from the beer in the line and eventually stabilize.

I would guess that maybe it is only important if you are going to leave the beer in the faucet for a long time. We only tend to get up there every other week so I just leave the glycol system going and the beer tastes fine just like it came fresh out of the keg.

I will take a couple more temps on different days to try and get an average and post the results.

If anyone wants me to take temps using a different method let me know. The first temps I posted were done quickly using a thick glass mug. This time I used a white styrofoam coffee cup and took my time letting the temp stabilize.

I still have not insulated the top of the coffin, cant do that until I install the fifth tap. So the temps are still probably off a bit. I have thought of topping off the coffin with styrofoam beads from a bean bag chair.

Air temp in the shed where the keezer is kept = 41F

E-bay temp controller, probe in a plastic travel mug
sitting on the compressor hump = 0.2C or 32F

Digital probe thermometer testing the same water the
e-bay controller probe sits in = 32.5F

Hard cider with the SS tube poured into a
styrofoam cup = 34.3F

Ale with vinyl hose poured into a styrofoam cup =35F

So is this done? If so, any finished pictures?

Here are a couple of updated pics, I still have some tweeking to do. I have to buy and install a fifth tap and seal the top. Other than that it's done. I'm averaging around 1.5 degrees difference between the interior temp and the beer in a glass temp. The real test will be during the warmer months.

Let me see if I followed this whole thread. The purpose of the detail of this project was to get beer in the glass thats as cold as the refridgerator is inside? And it appears off by 2 or so degrees....seems close enough to me....but my real question is what is the beer temperature in the glass without all this seemingly sophisticated setup? Maybe what 5-6 degrees off? If your concerened with your beer in glass temperature being too warm why not just discard the first 1/5th pint...? But, I imagine that the actual full glass temp would be much closer once the cold beer mixes with the slightly warm beer. Or is the real concern here having beer in pipes outside the cooling chamber...if so does that pose a real threat?

Thanks

ayupbrewing said:

Let me see if I followed this whole thread. The purpose of the detail of this project was to get beer in the glass thats as cold as the refridgerator is inside? And it appears off by 2 or so degrees....seems close enough to me....but my real question is what is the beer temperature in the glass without all this seemingly sophisticated setup? Maybe what 5-6 degrees off? If your concerened with your beer in glass temperature being too warm why not just discard the first 1/5th pint...? But, I imagine that the actual full glass temp would be much closer once the cold beer mixes with the slightly warm beer. Or is the real concern here having beer in pipes outside the cooling chamber...if so does that pose a real threat?

Thanks

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If you let the beer sitting in the lines at the top of the keezer get warm, which it will do if you just let it sit there and don't cool your coffin at all, you're going to get very foamy first pours until the lines cool down.

ayupbrewing

But, I imagine that the actual full glass temp would be much closer once the cold beer mixes with the slightly warm beer. Or is the real concern here having beer in pipes outside the cooling chamber...if so does that pose a real threat?

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I used an eight ounce styrofoam cup for testing. Yes, the beer temp of a Full glass would be closer but you would still have too much foam preventing it from being filled.

Since I don't like to drink foam and I don't throw away my beer, preventing the first beer foam was more of an issue for me.

I basically started this thread after following a similar one that used fans to cool the coffin beer lines/shanks. In that thread it was said that it was not possible to cool the beer down sufficiently, with in 8 degrees without fans. I actually took a lot of temps during testing and they ranged from colder than the temp probe indicated to around 2 degrees warmer.

Hope this answers your questions

Very nice design and detail. I'd like to more photos!