Introduction: Build Your Own Portable or Stationary Firepit
As we enter Fall in the US, it's a great time to get out and tackle some projects! And what better to make for the upcoming winter than your own firepit!?
Within this Instructable, I'll show you how to build two different types of firepits:
I'll start with a simple and portable version that many of you may have seen before. This style uses interlocking plates that easily assemble and disassemble. The best part, you won't even need a welder for this build!
I'll then walk through the steps for building a more complex and stationary hexagon style firepit that can be further customized with your own logos or lettering.
Step 1: Portable Fire Pit - Design and Planning
The most complicated part of this build is determining the correct geometry for the interlocking pieces. Not to worry - I've taken care of that part for you! Attached is a fully dimensioned sketch showing all five components that make up the firepit. These drawings will yield a pit with overall dimensions of 28x28x10 inches. This is a great size for portability and the perfect size for standard firewood which comes in lengths of 16 inches.
Materials:
All you will need for this job is one 4x8ft sheet of 3/16 inch thick plain steel. Using 3/16 inch thick material will yield a rigid final product that won't warp under the heat of the fire and will last a lifetime.
Tools:
I have access to a CNC plasma cutter which greatly helps to make builds like this quick and efficient. If you don't have access to a CNC plasma, you can cut these parts by hand with a straight edge and manual plasma cutter or even with a hand grinder and cutting wheel. There are some handles and vent holes which are not entirely necessary but are great additional features. If you do plan to use a cnc plasma, you can use the attached sketch as a guide to recreate the parts in a program like Fusion 360 in order to generate the necessary DXF files.
Step 2: Portable Fire Pit - Cutting Parts
Using the dimensions provided in the previous step, you can cut all parts from the 4x8ft sheet of steel. If cutting manually by hand, take some time during this step to ensure you measure and mark your components properly. If you're using a grinder with a cutting wheel, be sure to wear a full face shield. A straight edge can also help to keep your cutting disc or manual plasma cutter on the right path.
Attached are a few photos of the cnc plasma system that I used (full Instructable on the CNC Plasma build is available here! >> https://www.instructables.com/Home-Built-4x8ft-CNC...)
Once you've cut out all components, be sure to knock off any sharp corners or edges.
Step 3: Portable Fire Pit - Final Assembly
With all parts cut out and cleaned up, this pit is as easy as sliding the components together, dropping in some wood, and lighting it up!
The vent holes help to feed oxygen to the fire and the handles allow for easy repositioning.
Once you're ready to pack up, let the pit cool down and simply slide the components apart. The ashes will drop to the ground on their own.
If you're looking for a larger and more permanent firepit, read on for step by step instructions covering the build of my Hexagon Firepit complete with a removable grilling surface!
Step 4: Hexagon Firepit - Design and Planning
For this Hexagon Firepit build, you can keep it as basic as 6 solid sides or you can build in customized logos and grilling surfaces for added appeal and functionality.
I started with a CAD design. Programs like Fusion 360 are great options for working out the kinks in your design before commencing fabrication. I opted to make a hexagon pit with 14 inch tall sides and a 3 foot flat to flat width. Using your CAD modeling program, you can add logos and lettering to the side walls and have a local cnc plasma company cut these out for you (unless you have access to a cnc plasma yourself!)
Attached are a few sketches that show the exact sidewall dimensions you'll need for a 3ft wide pit. I opted to build my sidewalls from two separate sections of 3/16 inch thick steel plate. I used my homemade hydraulic press brake to help me make the bends on each half (full Instructable on the Press Brake is available here! >> https://www.instructables.com/Building-a-40-Ton-Hy...). The attached sketch shows exactly where you will need to make the bends (at 20-11/16 inches) and the required angle (120 degrees).
If you don't have access to a press brake, you can cut the side walls out as 6 separate pieces and simply weld them together.
I opted to add in a bottom plate and grilling surface. The grilling surface is designed to swing away or remove completely from the pit. The bottom plate helps to keep your fire elevated for better air flow.
Materials:
- One sheet of 4x8ft 3/16 inch thick plain steel
- 5/8 inch all thread and nuts for the grilling surface
- Black high heat paint
Step 5: Hexagon Firepit - Cutting Parts
Attached are some photos of the CNC Plasma cut parts along with an image of the components nested onto a single 4x8ft sheet of material.
If you don't have access to a CNC Plasma, you can hand cut a design using a manual plasma cutter or just leave your sidewalls solid.
You'll also notice a few small brackets and angles. These serve a few different purposes:
- Brackets to raise the bottom plate away from ground level
- Brackets for the grilling surface's swing away hinge
- Angle brackets for use as a guide when bending the sidewalls and welding together the two halves
Step 6: Hexagon Firepit - Fabrication and Assembly
With all parts cut out and cleaned up, you can begin marking, bending, and welding it all together.
Starting with the two side walls, draw vertical lines at 20-11/16 inches. These lines will serve as the bending locations. Make two 120 degree bends on each sidewall to create the two halves of your hexagon.
If you're working with 6 separate sides, you simply need to weld all sides together with 120 degree joints.
I used a couple bar clamps to keep the assembly rigid while welding.
I also cut out and bent up the grilling plate - an optional feature.
Step 7: Hexagon Firepit - Coating and Final Assembly
I used a high heat black paint to coat all portions of the pit except for the grilling surface. It is especially important to ensure you coat the intricate areas of any symbols or designs that you cut into the sidewalls.
For corrosion resistance, I used 304 stainless steel expanded metal for the grilling platform.
In total, this pit weights approximately 170 pounds. I spent a couple days designing and a couple days building it (part time).
Hopefully these steps will assist you in fabricating your own portable or stationary firepit! Thanks for checking out my build!

Runner Up in the
Metal Contest
17 Comments
1 year ago
If you shorten the portable fire pit sides to 24", you can make it from a 4' x 4' sheet of steel and cost your material cost in half. The distance between the ends will still be 19" and wide enough to handle typical firewood lengths.
1 year ago
Where do you source the metal? When I’ve looked in the past for small amounts, the places I’ve found charge extremely high prices.
Reply 1 year ago
Any local steel distributor can help you out! You'll just have to call around for the best price. The prices can vary greatly from supplier to supplier (I've seen 100 dollar differences in price for a single sheet of steel)
Reply 1 year ago
Try and find a large steel distributor in your area. Theres a very good chance that as they deal in larger volumes you can get smaller pieces for next to nothing. This project needs no more than around a square metre or so. Maybe a little more
Reply 1 year ago
Question 1 year ago
Hi, Great project!! It´s a silly question, but do you think a home grinder can cut this kind of steel sheet? I will try to do it, but do have have access to a CNC plasma cutter, neither too much expertise in metalworking...
Answer 1 year ago
Use an angle grinder with a couple of clamps to hold down the piece of steel you will use for a guide to make straight cuts. Take your time and you should have no problems. Have a couple of spare cutting disks on hand. Measure your cuts twice to be sure before powering up, wear your goggles and gloves, and you're good to go.
Reply 1 year ago
Thanks a lot for the tips. I'll give it a try and post here afterwards...
Reply 1 year ago
Hello, yes agreed with ArgleB's comment! You can certainly do this with a grinder and a cutting wheel. Just be patient with it and let the cutting wheel do the work. I always wear a full face shield when using cutting discs on a grinder since these can be rather dangerous if they fail
1 year ago
What a great simple design! Even someone with an Oxy/Ac torch and a steady hand could make this. Might be a little redneck but completely functional.
1 year ago on Introduction
wow...nice and simple....i've been researching plasma cnc's. made 2 cnc's, one wood/aluminum, one laser....both stille work great after 3 yrs...about to watch your build. torch height control? what did 3/8 4x8 sheet cost you? anyway, like the hexagonal pit, and cant wait to buy (possibly langmuir) or build my own. your cnc looks nice and beefy.
Reply 1 year ago
Thanks! Yes I have torch height control. The 3/16 inch plate I used to make the firepits was around $300 to $350 depending on the supplier
1 year ago
How heavy is the portable one? Now to find a CNC plasma cutter...
Reply 1 year ago
Around 40-50 lbs I believe (I have not specifically weighed it before)
Question 1 year ago
Have any will to sell the cut plates leaving the welding to be done by the buyer?
Question 1 year ago on Step 7
Are you making the .dxf files for these available?
1 year ago
I love the comment "The best part, you won't even need a welder for this build!"