How to Make a Coffee Fire Log




In this instructable, I'll show you the basic recipe for making a Coffee Fire Log. The recipe could still use some tweaking, but it's a good start and a fun and easy project.

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Step 1: Gather Ingredients

From my searches on the web, there are three ingredients in a FireLog; coffee grounds, wax, and molasses.

I used a bread pan to combine all the ingredients and press the loaf.

I used candles, but you could use the blocks of wax they sell at craft stores (will try during next attempt).

Also, make sure the coffee grounds are completely dry. You can get the grounds free from any Starbucks. If they don't have any sitting out (for compost), then just ask. They are more than happy to get rid of them.

Step 2: Combine the Ingedients

I put two and a half candles and the molasses into the bread pan. I usually fill the bottom of the pan with a generous amount of molasses, but I ran low for this last batch.

Now we need to melt the wax. I put the pan in the oven (as pictured) at 260 degrees. I also put the coffee grounds, in a metal bowl, in with the pan to dry them more. It takes about 25 - 30 minutes for the wax to fully melt

Step 3: Add the Coffee Grounds

At this point the wax should be completely liquid and the molasses will have probably settled to the bottom. Stir it up a bit. I used a chopstick, but if you have cheap whisk you don't care about, it would probably work better.

As you can see in the second picture I start adding the grounds one scoop at a time. The wax may fizzle and bubble when you add the first scoop, like in picture 3. If it fizzles as much as shown it probably means you coffee grounds are still moist.

For this amount of wax and molasses, I used 5 heaping serving spoonfuls of grounds. The entire recipe can be doubled to produce a larger log (which I plan to try next).

You'll know your done stirring when all the grounds are dark and slightly glossy (Like in the 5th picture). Make sure you stir in all the corners (this is when the chopstick is handy).

Step 4: Form Your Log

The next step is to press to grounds in to a solid form. I used aluminum foil, but you could probably use wax paper or plastic wrap. I think for the next time I'll cut a block of wood to size and use that to get an even and firm push.

By this time the wax should have cooled down a lot, but make sure you test it first. If it's too hot to the touch, let it cool some more, you will still be able to mold it. Cover the pan with the aluminum foil and start to press down like in the first picture below. Make sure to get the corners as well. Once you feel you got it good enough (doesn't have to be perfect, after all you're just gonna burn it), you can let it dry overnight or you can throw it in the freezer for about an hour. You can see how far down mine went in pictures 2 and 3.

Step 5: Release Your Log

You final product should look nice and glossy like mine in picture one.

Use a knife and cut around the side of the pan to loosen up the log. You can either try to pry it out or turn the pan upside down and bang again the counter. I should look like picture 2.

Step 6: Burn Your Log

This is the fun part.

5 or 6 sheet of newspaper under the log should be enough to get that puppy fired up.

Now sit back and relax.

These logs don't last as long as the store bought ones, but I figure with enough people tinkering with the recipe we can get in mastered!



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    75 Discussions


    6 years ago on Introduction

    I found this alternative recipe in patent: A coffee ground-based fuel composition comprising of: (A) dried spent coffee grounds by 54% by weight; (B) vegetable shortening; by 23% by weight; (C) brown sugar by 20% by weight; and (D) corn syrup by 20%

    3 replies

    Reply 1 year ago

    I will try that. Thieve ideas are so neat.


    Question 11 months ago on Step 2

    What does molasses do in this process?why will the log not burn if only wax and coffee grounds are added?


    Question 11 months ago on Step 6

    I melted wax using double boiler method & made a small log. When i tried to burn it using Bunsen burner only the wax used was getting melted. I am disappointed. What should i do?

    foxtrickleRemya Narayanan

    Reply 11 months ago

    I used Brer Rabbit Molasses "Full Flavor". I'm not sure what the difference is.


    Reply 1 year ago

    I wld certainly prefer vegetable oil

    I've wondered about other the fireplace logs you purchase; my plan for after I make the coffee logs is to read ingredients on 6 different logs...there are logs on the market made from grounds as well as manure (yes! quit worrying about your Starbucks "fragrance"). Before I play around with other parafin substitutes will try to check with a chemist.(this will be most expensive ingredient and could possibly be diluted with mineral oil or ?)


    3 years ago

    I used my cheese grater and grated the candles over the coffee grounds, mixed and grated dark brown sugar. Mixed again and stuffed in 1/2 and pint waxed milk/ juice containers. So easy, burned great, hot and long!! Thanks for the posting to get me started!

    3 replies

    Reply 1 year ago

    Did you just light them still in the containers?


    Question 1 year ago on Introduction

    I tried and absolutely luv these things! I do add oatmeal and it burns beautifully. Altho get them formed is a bit of a hassel than out of the pan. I was thinking would leaving it loose in a fairly Think layer work? I almost think you could use less wax. Any thoughts?


    3 years ago

    These are all GREAT ideas. Between me and the Starbucks across the street I should be "In like Flynn" with coffee logs.

    Thanks for all the innovative ideas, they are much appreciated.


    4 years ago on Introduction

    I used the alternative recipe with the brown sugar, corn syrup, and used old bacon fat (burns nice and long and doesn't wax up your fireplace). It seemed too "wet" to burn, but used your idea of popping it in the freezer. Also like the idea of getting molasses from a feed store - who knew??!! Also making newspaper logs. Tried making both logs last year during the winter (NOT brilliant to be making them outside in Canada...brrrrr), so this year stocking up for winter and cozy fireplace evenings. Thanks all for your ideas and suggestions.

    So I know this is a older post. But I just ran across it. I was thinking as far as cost is concerned d/t the molasses why not use the molasses from the feed store? I know here they have Large containers for literally dirt cheap vs what I buy for human consumption at the market. Im not sure if humans can eat the other, but that is beside the point since we will just be burning it. Just a thought. Happy prepping