Last Friday we paid our sheet metal manufacturer (located about 3 hours south of Atlanta) a visit to check up on the quality issues we mentioned last update, and to pick up shells in all the final colors.
Headin’ down south to the land of the pines
As mentioned last update, we’ve been working with the factory to solve some of the QC issues. We’re seeing some problems with consistency as they move to larger volume runs. The quality is great when they carefully work through small runs of 2-3, but as we’re moving up to 50-unit run sizes, we’re seeing issues that afflict some - but not all - shells in a run.
For your viewing pleasure, here’s a photographic walk through of the shell-making process, with our problem areas.
Beyond showcasing Gleb's nascent constructivist leanings, this scene shows the finishing step of the raw shell. After the sheet metal is bent and welded, the weld spots and seams are ground down to smooth out the edges. One problem we’re seeing is that the amount of weld and amount of grinding on the corners of the shells varies from machine-to-machine. While we’ll always see some weld on the inside areas of the machine, we’re looking for a consistent amount and placement.
A pile of shells waiting for pre-powder-coating inspection.
After welding/grinding/inspection, shells are loaded onto a conveyor that draws them through the powder coating and curing process.
Powder coating in progress. A trained painter sprays colored powder onto the shells, which clings statically to the metal before being cured at high heat. Ensuring that the powder is applied evenly is an art and essential to getting an even finish. Once we’re up-and-running at full scale, we’ll switch to machine powder coating, which automates 90% of the coating process (leaving just touch-ups to be done manually).
Red, green, yellow and black shells hot off the line and ready for inspection of the powder coat. One area of inconsistency is in the seams - sometimes the powder successfully masks off the seams between surfaces, but in other instances it leaves gaps between the surfaces.
Closeup of green and yellow. We’re seeing a problem with the yellow, which is the lightest color and consequently requires the most TLC. Basically, to get a nice glossy finish without a lot of orange peeling, there’s an optimal coat thickness, but at that thickness (or thinness) the metal still shows through in areas on the yellow shells (it doesn’t show up in photos, but when you look at it you sort of see the shadow of the raw steel in some, but not all, areas). They’re going to switch to a different powder (same hue, different polymer) and see if they get better results.
When the powder coat comes out wrong, they try to burn it off to recoat the shells. It works some of the time. When it doesn’t, rejected shells end up in the graveyard.
Some insight into QC. Each piece that comes off the line is compared to an ideal, approved piece and must be within designated tolerances of that piece to be deemed ‘acceptable.’ Here we are with the target pieces, working out ways to eliminate some of the things that keep causing problems during manufacture.
We do have one piece of good news: we have all the colors! Without further ado:
The whole family together.
We’re still working on fancy-schmancy product photography, but we wanted to show you guys the whole lineup. That little guy in the upper left is teal, which will be replacing green/yellow/blue (our least popular - or most special - colors) as we go forward. (Anyone who has already ordered green, yellow or blue will still get that color - we just won't be taking new orders in those colors.)
In terms of timeline, we’re still backed up on board revision and will hopefully know more next week about what to expect moving forward.
We finally got word that working revised boards are in-hand with the board designer, and we’ll pick them up tomorrow morning. If all goes well, we’ll be able to start publishing video of how the GUI works, now that it is fully functional and displaying correctly on the screens, and restart the UL process with new boards.
Until next time,
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