Can I weld a mini Christmas tree? #
For this week’s assignment, I decided to do a small welding project as I was working on a final paper for a class so my time was limited. I decided to design a small Christmas tree with holes so I could organize my earrings on them. Festive and functional!
Design and Waterjetting #
I decided to waterjet pieces of steel in the shape I wanted and then weld them together. To start, I used Fusion to CAD my models. Since waterjetting only requires a dxf, or 2D drawing, this part was pretty simple.
Unfortunately, I did not make the tabs big enough for the first pass so the first few pieces fell into the waterjet…
I changed the tab sizes in omax path and then the pieces were successfully retrieved.
I find that gently yielding the pieces back and forth is the best way to break the tabs and remove the pieces from the stock.
I decided to cut one large panel, then two smaller panels that will be welded perpendicularly to the large panel. I then uploaded the dxf to the OMAX waterjet in the N51 shop, and cut out the pieces from a 1/8" 4130 cold steel plate. I used steel because welding aluminum is very tricky.
Welding #
To prepare my pieces for welding, I used a wire wheel attachment to polish the surfaces of any rust, and to make them shiny and porous. This prep work can be tedious, but it is important in ensuring a good welded joint.
I used a TIG welder at 120 amps and 40 cubic ft / hour of argon shielding gas for my pieces. One amp per thousandth of an inch is generally a good rule of thumb for TIG welding, and since I was using 0.125" steel, this was a good current.
I wore TIG gloves, a welding helmet, and a welding jacket.
Fixturing the tree was a challenge due to its irregular and small shape. I tried using some right angle brackets and clamps with dubious success.
I only welded two seams because I didn’t want too much heat affection.
Reflections: #
- Always check tab sizes relative to stock you are cutting!
- Design tabs at joints for welding ease
- Use more fill rod to avoid undercut