This week I really wanted to make a stainless steel double walled firepit, like the solo stove. I started designing it in fusion360. I made an initial design that was complicated and included custom mountain shapes for the lower vents, as well as my initials. However, I wanted to keep it simple this week so I choose to make circle vents instend. I also kept the firepit size to a reasonable diameter for me to carry (14").
I delibrately made the design in fusion to start so I could see how the finished product would look, but then I switched to using adobe illustrator to make the final dxf file. I didnt want the all the joints to join perfectly, but rather design in overlapping material that would be easier to weld. I did this through simple math to calculate various circumferens. I ensured that the seems of the rolled panels would overlap at at least half an inch. My intent was to use that material to weld too, as opposed to using filler rod. I found stock stainless in the hobbyshop and recycled it for this project. The original sheets were large at 68x36 inches.
The waterjet (OMAX) in the architecture shop has a cutting area of 48x24 inches, so I needed to reduce my stock material to fit. I did this manually with an angle grinder and a cutoff wheel
I uploaded the .dxf file to the omax with Shah and Jen's help from the architecture section. Using the .dxf, we made CAM for the OMAX. The machine automaticalled calculated its own kerf as well as lead in and lead out cuts for the various shapes. Below is a video of the machine working.
Above are the output stainless sheet products from the waterjet opperation. I need to further fabricate the metal to make a firepit. First, I rolled the rectangual sheet with the sheet roller, this took some finessing and I'm glad that I added some margin into the .dxf file. Below are before and after pictures of the steel being rolled.
Above you can see the welding setup in the hobbyshop. I'm using a TIG set up at 75A, Pulsed DC current with an average gas collet on. This is only my second time tig welding and I decided to do a few practice lines on scrap.
Prior to running full beeds around the whole project, I had to assemble the pieces together in a way that would be easy to weld and ensure that I could access all the seams. I then tack welded the inner tube in place.
This is my finished firepit, I can't wait until I get to use this bad boy to try out some smores.
