Documentation

Add solder to
these pads
3A: Pre-tinning the
assembly pads
3B: This is how much
solder you should use
on each pad
4A: Using masking tape to
align the boards before soldering
7
Step 3 - Preparing the Main Solder Pads:
We’re going to pre-tin (melt some solder onto) 8 pads on the PCBs, so all we have to do
after is align them and reheat to make them stick. Make sure you melt a generous
amount of solder on these pads, like shown in figure 3B.
Solarbotics Herbie the Mousebot
Step 4 - Assembling the Main board, one Side board, and Battery Board:
This part can get tricky, so we suggest bringing out your secret weapon: Masking tape!
Yes, this stuff should be in every good roboticist’s toolbox (right next to the Oreo
cookies). Unless you have a 3rd arm growing out of your chest, use the tape to keep
things aligned. Or if you can bribe somebody to help (use Oreos...).
Now, review this whole step before starting it. And look at the
pictures - they make everything clearer.
You have to make sure you get the two alignments correct:
1) Align the long edge of the two big circuit boards so they sit
edge-to-edge, with no overlapping. This is easy to do while
they are taped together.
2) Align the little half-circles on the two big circuit
boards so they match and make up one full circle.
For the moment, use the battery board to just line
up all three sides of the Herbie body. But
remember to put the battery board in so the
connectors face to the rear.
When the boards are aligned, remelt the solder on
the front pads first, then the rear pads. Add
more solder if needed. We do the front pads first to make absolutely sure the nose is
aligned to take the nose bead later. Double check to see that the half-circles are still
aligned. If they aren’t, fix it now - it’s that important!
(Continued next page)