An epic battle with extruded polystyrene

[chillHayze]

Today I attempted to assemple a son-of-fermentation chiller thingy. I found all me parts including 2 2X8' sheets of extruded polystyrene (XP). So i jam the XP into my hatchback and procede so squeak down the road. I get home, decide I have nothing to cut the **** with. Tramantia kitchen knives to the rescue! It is going well then I cut a few pieces wrong and run out of liquid nails. I used a lot to make up for the sub-par cutting of my cleaver. Tried gorilla glue I had on hand - no luck with that on the XP.
So now I need more XP and liquid nails. Oh well, another day. So I figured I'd wire up the thermostat and fan. I bought an electronic thermostat - apperantly a bad decision. It fried my 12V power supply and the closest thing I have is a 7V that won't even spin the 80mm fan. Dang it all!
In the midst of all this, I killed a keg of Apricot Wheat...and tapped a Wit.

So I need to return the thermostat, buy a mechanical one, buy more XP for a lid, and more liquid nails!.
Oh, and cant forget to relax and have a homebrew.

Sine I'm in a pic taking mood...here are some pics!

Mad knife skills.

Reaction of gorilla glue and liquid nails.

EMPTY!!

 

[Monster Mash]

A hot wire is the best way to cut pink foam. I use piano wire, a bow and a rheostat to adjust the heat. It cuts like butter...

 

[chillHayze]

Dude that is way cool. Like an assasin, only with hotter wire.



Update: It seems my EE degree failed me and I hooked up the 'stat wrong. I've got it right now, and found a 7.5V power supply I had which is enough to start the fan. Also, I've decided to go with 2 seperate lids. One for the beer side and one for the ice side. Should be more efficient and I can use the scraps I have to make it work. This new keg is making all sorts of good things happen!

 

[olllllo]

I have used an old soldering iron and thinner guage wire for the tip as a quick hack to hack out cuts in styro.

You can get an el-cheap o soldering iron at Big Lots or a dollar store.

 

[Brewsmith]

Electric knife?

 

[Pumbaa]

a hot wire is best to cut with, I used a jig saw cuz thats all I have, the electric knife would work well too if ya go slow. BTW I used like 6 tubes of liquid nails since I cant cut for crap so dont worry it makes a nice filler. If ya need a source for CHEEP power supplies and fans let me know PM me or something I'll send ya a link

 

[chillHayze]

I've got this 7.5V that will spin the fan but I suppose 12V would have better cooling performance. I dont need a fan - I'm using an 80mm fan I bought a few years ago. Even has blue LEDs in it!

 

[raceskier]

I had the answer, but I see Monster Mash beat me to the punch. And from his pics, I know just where he was using that hot wire. I am also an RC model airplane guy like MM. We use the hot wire to cut accurate airfoil shapes from the same kind of foam and then cover them with carbon fiber and fiberglass and epoxy. (I use a variac, variable voltage ac transformer for power.) Makes a really effective wing for a model sailplane. Cutting nice square pieces to make a cooler would be snap. The trick is to make templates of the shape you want out of something that won't burn too easily and attach it to the foam. Then just use the hot wire to cut the foam to the template. The Gorilla glue is another model airplane favorite. The expansion during cure can cover a multitude of poor fit up problems, particularly for something like this cooler project. Where I work (aerospace biz) we build a lot of temporary thermal chambers using urethane foam. It can't be hot wired, we ususally band saw it. One trick though is to cover it with a durable plastic film. It greatly improves the ding resistance. Looking at a lot of the homebrewed coolers, it would seem like after repeat ably putting a keg in and pulling it out, you'll gouge the cooler walls and have bits of foam all over the place.

 

[chillHayze]

Made another trip to the Depot today and obtained the rest of the supplies. More liquid nails, 20' of 7/8" thick weatherstriping, powerade, etc. Did some more cutting and made up my two lids. I measured the cut for the small lid several times cuz I coundn't believe it was that crooked. All those high spots really add up when you get to the end of the project. So I cut my crooked lids up and found that it was a good thing I bought 20' of weatherstriping...
I even had to build up a corner with liquid nails cuz it was so far away from sealing.

Supplies

Ain't she a beaut'?
Note the top notch putty job on the corner.

Seamless, I tell you.

Fan go VROOM!!!​

 

[Jester4176]

I've been wanting to build one of these, but it's just not economical for me. The cheapest place I can find the XP in town is $30 for a 3x5 sheet, and it'll take 3 sheets to build the chiller. Just got my hands on a HUGE white styrofoam bead cooler though. It has 1 3/4" thick walls, and enough room for 2 fermenters, but I'll have to cut a hole in the lid for the top of the carboy because it's not real tall. I'll post up some pics when I get a chance.

 

[chillHayze]

It was 12$ for a 2"X2'X8' sheet. I used 2. Total cost was about $80 but it would have been closer to $60 If I could cut the lines smoother (less liquid nails and weather striping). If you are building a chiller for one fermentor only, 20wX24LX26H would work. Mine was 24wX26LX30H because there was less cutting involved.

 

[Monster Mash]

I bought a 14cu ft freezer off craigslist for $60.... Im sure it costs a little more to run but it makes lagering easy...

 

[Jester369]

As an alternative to the hot wire cutting, since all the edges appear to be squared, a table saw kicks butt on that foam. Perfectly smooth cuts!

 

[chillHayze]

I bought a 14cu ft freezer off craigslist for $60.... Im sure it costs a little more to run but it makes lagering easy...

Yeah I just don't have the space for that, and wanted a project, lol. I'll try a lager in this but I understand that will require more frequent ice changes.