Category Archives: Keezer / Kegerator

Compact Fermentation Chamber Heater

We all know the importance of temperature on fermentation.  However, often when we put temperature controllers on our fermentation chambers, we only need to worry about cooling.   In this post I’m going to show you how to make a simple compact heater for your fermentation chamber.

Difficulty: level_2

This is a fairly easy project.  It just requires some empty food cans, a small light socket and some lamp cord.  It should also not take any longer than 30 minutes once you have collected all of the parts.  The main cost for this project was the light bulb base, which was only about $5 and whatever you need to spend on bulbs.  The remainder are tools and components you can source from around your home.


Up until now, I’ve only used my fermentation chambers for lagers and since everything inside my house, I’ve only needed to cool.  Well this WAS ok until I needed to do an ale and my fermentation area in the basement only peaks at a cool 60 degF.

I also use converted dorm fridges and didn’t have space for a full size light bulb fixture and didn’t want to bother with the heating pad type heaters.

Necessity is the mother of invention…

Materials / Parts Needed:

  • Standard size container from canned vegetables
  • Tomato paste can
  • Spare lamp cord
  • Candelabra socket
  • Candelabra bulb
  • Electrical connectors and covering of your choice
    • Wire nuts
    • Butt splices
    • Electrical tape
  • Drill
  • Tin snips
  • Deburring tool
  • Stepper bit (helpful)

020-Fermentation Chamber Heater - bulb heater parts needed

Obligatory Disclaimer:

If you are not comfortable working with wiring or electricity, please hire or find someone who is competent.  Also, be sure to place the finished heater in a location that will not get wet.

How to make:

Collect the cans and clean them

I used a can from some green beans and a tomato paste can.  Make sure they are all metal and not plastic lined.  Since you are homebrewers and obviously know how to clean and de-label containers, I won’t go into that.  I will however say that you want to try and get rid of as much of the smell from the original contents as possible.  The first use made my fermentation chamber smell like spaghetti sauce.

Cut the cans

Base / Tomato Paste Can

Drill a hole in the bottom of the tomato paste can as a pass through for the candelabra base.  I pre-drilled with a standard drill bit and then cleaned it up with a step bit.  I also used a deburring tool to clean up the edges.

020-Fermentation Chamber Heater - hole in bottom of tomato paste can

020-Fermentation Chamber Heater - stepper bit drilling in tomato paste can

020-Fermentation Chamber Heater - rough hole in bottom of tomato paste can

020-Fermentation Chamber Heater - looking into the bottom of tomato paste can rough hole

020-Fermentation Chamber Heater - deburring tool

Then to cut it to length, it is easier if you pre-drill a hole to start your cut with the tin snips.  Also, you may need to make another cut up the side to allow you to pull the metal aside as you cut around the can.  BE CAREFUL, THE METAL IS THIN AND SHARP.

020-Fermentation Chamber Heater - determine height of base

Since the cans are smooth and curved, it was helpful to center punch your hole location to give your drill bit a good place to start.

020-Fermentation Chamber Heater - center punch

020-Fermentation Chamber Heater - housing center punched for drilling

020-Fermentation Chamber Heater - housing pre-drilled for cutting

020-Fermentation Chamber Heater - vertical cut on can

I also cut a simple pass through for the cord and you’ll want to cover the edges with some electrical tape so you don’t accidentally cut the cord.

020-Fermentation Chamber Heater - clearance cut on base

020-Fermentation Chamber Heater - protective tape on base

Housing / Standard Can

All you need to modify on the housing is to drill a hole for the wire to pass through.  I actually just cut a 1/2″ diameter hole and then used a spare grommet from one of my fermenter lids to protect the cord.

020-Fermentation Chamber Heater - housing with grommet

Attach the candelabra socket to the base

This is pretty straightforward.  Just take the collar off of the socket, feed the socket through your hole and tighten the collar.

020-Fermentation Chamber Heater - candelabra base assembly

020-Fermentation Chamber Heater - candelabra socket installed in base

Feed the wire through the hole in the housing

020-Fermentation Chamber Heater - base installed in housing

Connect your power cord to the light socket

For this, I’m going to direct you to the interwebs to figure out which wire goes where:

Lamp cord polarity

020-Fermentation Chamber Heater - crimped butt connectors

020-Fermentation Chamber Heater - electrical tape on butt connectors

Install the bulb

I started with a 25W candelabra bulb that we had on hand for our sconces in the basement.  It heated my converted dorm fridge from 55 to 65 in about an hour with nothing in it.  I would suggest trying different wattages until you find something you are comfortable with.

Remember, just like electric heating elements in kettles, the concept of wattage density could matter.  If you go too high on the wattage, you might risk melting some plastic inside your chamber, the bucket or create a focused hot spot in your fermentation vessel.

020-Fermentation Chamber Heater - finished compact bulb heater

Plug into the heater side of your temperature controller.

020-Fermentation Chamber Heater - testing compact bulb heater

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Fermware DIY’s featured in Zymurgy’s 9th Annual Homebrew Gadgets Issue

I’m honored to have two of my DIY’s featured in Zymurgy’s 9th Annual Homebrew Gadgets Issue!
My two posts featured were:
The very popular Homer Hopper build complete with CAD templates.

Difficulty: level_3

Zymurgy has been kind enough to allow me to post the article on my website, so just read the article and support the AHA!

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Merry Christmas and a Hoppy New Year!

It’s a cheesy title, but I couldn’t help it.  Many of you have seen the post on my 3D Printed Tap Handles and I’ve gotten an overwhelming amount of interest, which is precisely the reason I have not posted anything new in about a month.  In this post, I’m going to show my 3D printed Hop Cone Christmas Light Covers.

Difficulty: level_5

Due to the investment in a 3D printer and the amount of time it takes to get one dialed in and making parts, this one gets a high difficulty rating.

You also must posses some CAD design skills to generate the required files to send to the 3D printer.

Time Required:

For the print time only, my virtual hop farm takes about 8 hours to grow.  Much quicker than real hops.


$300 to $3000 depending on how nice of a printer you want to get.


A 3D printer


Recently, my printer has been running as much as the ideas in my head.  Having a 3D printer lets your imagination run wild and here I’m going to show you my latest brewing related creation, Hop Cone Christmas Light Covers.

017-Homer with lights on in light

Yes, that’s my Homer Santa Claus.  It was a gift from a great friend many years ago and I still look forward to getting it out every year.  The camera failed to do the color justice when the lights are lit, but they glow a pretty standard green.

My latest revision to the 3D printed WBHY Tap Handles was printing translucent filament over some standard gold filament to create a flask that looks more like what you have when making starters on your stir plate.

016 - WBHY Handle v3 - yeast flask

With that checked off on my wish list, I thought it would be awesome if I could make some slip on covers for Christmas lights that looked like hop cones.  Then beer nerds everywhere will have a way to decorate their kegerator, keezer, bar, brewing area or even your beer Advent calendar.

Assembly and Design

I started with the hop model I made for the tap handles, then hollowed it out and through a few iterations, I got the proper internal tabs to slide right over standard Christmas lights.

017-Into the hop

017-Inserting bulb into hop

Pretty simple really!

Here are some shots of the lights in different states with Homer modeling them.

In the light with the hop lights turned off

017-Homer with lights off in light

In the light with the hop lights turned on

017-Homer with lights on in light

In the dark with the hop lights turned on

017-Homer with lights on in dark

Growing the hops

Don’t you wish you’d get this kind of yield overnight?

017-Hops Printing

017-Hops Finished

The material is a translucent green PLA.  I started with the basic recommendation of blue painters tape, but experimented and I can now just print right on the Kapton tape.  I’ll try to be bold next and print without the raft.



I would recommend only using these on LED lights.  Standard incandescent lights do put off heat and I have NO idea what will happen after long term usage on those lights.  PLA melts at lower temperatures and could damage the lights or the lights themselves might overhead and burn your house down.  LED lights on the other hand, put off very little heat.  That’s one of the reason’s they are so efficient!

Want to build your own?

Here is the Thingiverse link so you can download and print your own.

Don’t have a printer and want to buy some?

I’m offering a printing service for those that don’t have a 3D printer and would like a to add these hop covers to their own lights.

Everyone should understand what cosmetic quality one should expect from a 3D printed part and the pictures on this post I feel, do a sufficient job of it.  I will not do any finishing work on the hop lights.  I feel that the as-printed look is part of the charm of these parts.

Lead time from the date of order could be up to three weeks.  I realize most people will want them while their Christmas decorations are still up, so I’ll be going flat out to get them to everyone ASAP.  If you have a drop dead date to receive them, give me an entire week’s notice and I’ll let you know how my schedule is looking.  Do NOT order unless you are fine with the standard lead time or you’ve gotten confirmation from me on delivery.

Use the links below to purchase via PayPal.  Shipping to the US only at this price.  If you live outside the US, contact me through the contact link in the top menu bar of the site.


ALSO, I’ve only made available the covers for the most popular 7mm diameter “crystal” LED lights.  I tried these on a few different brands of lights.  These lights also seem to go by the size “M5”.  I’ve almost got the mounting for the smooth skinny LED lights (5mm diameter) worked out.  Although not recommended, the 5mm version will fit the standard incandescent Christmas lights that everyone had up until LED lights became the rage.

Those 2 are the only sizes I plan to release.


*If you have Paypal purchase problems, let me know

Hoppy Holidays!

017-Group of 10 hops