As I was soldering this for a friend whose Razor Crest Project is running way faster than mine, it got me to thinking some things. Sure, I’ll get a very nice trade off from this but this is not the issue. The 37 LEDs took me three hours to solder onto the pair of engine PCBs. Right now, in the middle of a heat wave where the temperature is in the mid thirties Celcius, it is no fun at all.
There is a way to speed things up and as usual, either way involves money. I did discuss about this some time ago on getting reflow hot plates. This solution, which to me, is cheaper in the long run compared to assembly outsourcing for each order or project. Right now, the solution requires the following basic items:
– Hot Plate,
– Solder stencil (USD7.00), and
– Solder paste (which has an expiry date. Woe if you seldom use it)
However, before I can begin, there is also a matter of redesigning the engine PCB a little. You see, the 0603 ring LEDs were designed for hand soldering and if I did use reflow, the current design would position them about 0.6mm out of alignment. In other words, for the AMT, these LEDs are going to hit into the inner edges of the engines which could destroy the fragile LEDs.
SHOW I OR SHOULD I NOT?
Right now, I’m not sure how many units I can solder and the startup cost is quite significant. Plus, I have yet to write a proper assembly manual for it. If I do get this hot plate which has a working surface of 5.6cm x 5.6cm, the Razor Crest Project is the only project which benefits from it. The main reason, apart from soldering the tiny 0603 LEDs, is to solder the 0603*4 resistor network array reliably. Oh, and of course, the fun of watching the solder melts and re-position the SMD components by itself.
But seriously, this is something I have yet to convince myself that investing this tool for a one-off (for the time being) Project is quite expensive. Being a sadist, I guess I’ll have to hand solder these boards for the time being. The argument of having the boards ready within minutes compared to hours is quite compelling but it’ll just have to wait.