This method is a really easy way to get nice looking 3D extruded profiles.
The sign features interchangeable acrylic plaques with things like "Please wait to be seated" and stuff like that.
Other than the initial laser cutting of the profiles you won't need much in the way of tools to make shapes like this.
A 9" grinder
A 5" grinder with 80 grit sanding discs.
A welder, MIG and TIG
Hammer, Files etc.
3mm Cold rolled mild steel sheet
25x25mm Square Hollow Section
15x15mm Square Hollow Section
6mm Mild steel plate
I made a model in 3D for the laser cutting profiles and to get a cut list for the other parts.
Step 1: The Base
The top was a piece of 6mm steel plate.
The plate was cut about 10mm smaller around to allow for a weld and a bevel
This lets you do a fillet weld around the plate and frame, leaving enough weld to grind flat, leaving a nice
beveled edge. (See Weld detail below)
1. Fillet weld 2. Weld ground down to bevel, leaving sufficient weld to hold.
1. Not enough space for fillet weld. 2. Grinding down leaves little to no weld holding the two together.
I also did a few 50ish mm long fillet welds on the insides first before I fully welded the inside.
Total overkill really but I wanted to make sure this thing sat dead flat. A few tack welds would be enough
The problem with welding on one side only is you're likely to pull the SHS around.
One side gets hot then contracts pulling the SHS, see Detail 2.
1. Welded both sides, SHS stays flat. 2. Welded outside only SHS pulls around on it's corner (exaggerated)
Having said all that we aren't building a spaceship, this thing just sits there, so getting these weld details exactly right isn't necessary.
It's a good thing to keep in mind though when welding/finishing, coming from a boiler/structural apprenticeship
this is just habit now for me to do these thing this way.