lots of text

expansionadding.md

@@ -42,6 +42,10 @@ Flux, whilst useful, can leave nasty sticky areas on your board. You should alwa
 
 We use this one - [Ambersil 30216-AB Flux Remover 400ml](https://www.rapidonline.com/ambersil-30216-ab-flux-remover-400ml-87-7352)
 
+### Tweezers
+
+A good set of tweezers so you can hold the exapnsion board.
+
 # Adding your board
 
 The expansion boards have small notches on the side (that are called castellated vias) that we need to solder to the pads on the main board. Soldering these maybe new to you and seem a bit daunting - don't worry though as it's not as difficult as it looks.
@@ -58,4 +62,43 @@ You'll notice a small white dot next to the expansion area on your main board. I
 
 ![orientation](/images/expansionorientation.jpg)
 
-When you place the expansion board on the main board, you should line these two dots up.
+When you place the expansion board on the main board, you should line these two dots up.
+
+### Soldering the first pad
+
+Add some flux to each of the pads on your main board. 
+
+If your main board is the SOAR board then you will need to add a bit of solder to one of the pads - we recommend the right hand pad on the same row as the white dot. Once you've added some solder, add some more flux over the top of it.
+
+### Attaching the board
+
+Now add some flux to the edges and pads of the expansion board. Once you have done that, pick the exapnsion board up with your tweezers, making sure that it is still in the correct orientation.
+
+Hold the exapnsion board on the main board and try to line up the small notches on the expansion board with the pads one the main board.
+
+Once you are happy, apply some heat with your soldering iron to the first pad you picked earlier and you should see the solder flow and join the two boards together.
+
+Remove the iron and let the joint cool down, then let go of the exapnsion board with your tweezers.
+
+If the board is slightly mis-aligned then you can apply some more flux to the first pad, re-heat it with your soldering iron and move the exapnsion board with your tweezers until it is lined up.
+
+Again, make sure you remove the soldering iron **before** you let go with the tweezers so the solder hardens and keeps the expansion board in place.
+
+### Solder the rest of the pads
+
+Now the first pad is soldered and the two boards joined, it's time to solder the rest of the pads. Make sure you have flux applied to each pad and notch (add some more if you are unsure - it won't hurt).
+
+Melt a small amount of solder on the end of your soldering iron and touch the next pad, you should see the solder reflow and the flux will pull it to the expansion board and join them.
+
+Continue with each pad in the same way (with a little bit of solder on the end of your iron). Leave the pad next to the white dot until last.
+
+### Ground pad
+
+The ground pad ( the one next to the white dot ) is the trickiest to solder as it is connected to the *ground plane* on the main board and will take a bit longer to heat up.
+
+Add more flux to that pad (and the exapnsion board pade and notch) and, with some solder on your iron, place the tip so that the end touches the expansion board and a bit of the body touches the main pad. 
+
+You'll need to leave it there for a little bit longer than you did with the other pads, but it will heat up after a few seconds and you'll see the solder flow in the same manner.
+
+Congratulations - you have now attached your expansion board. 
+