Part 6 - Turret board wiring





Once your turret board is soldered up with components, flip it over so that it's face down and with the two ground bus wires towards you (it will look identical to the top-most photo above). In this step, you will add the hook-up wire. Most of the wires from the turret board fan out from the underside of the board, but at this point, you're only adding the wire to the turrets - not any other component.


Estimating wire length

Before you start trimming and soldering, do some 'dry runs' to get a good idea of the length you need for each wire. To do this, add the mounting hardware for the turret board to the chassis. Add four M3 screws and M3 spacers to the holes circled in red in the photo below.



Now you can place the board (components facing up) in the chassis and use the diagram at the top of the page to see where each wire runs. Most wires run to the valve sockets, grounding lugs and front panel components. Your kit contains plenty of wire, so err on the side of having overly-long leads that you can trim to length later (because it's a pain to extend leads after the event). The longest wire is the red one (point C) that runs all the way to the output transformer - make that wire approx 30cm (12-in) long.


Adding the wiring

If you're new to amp building, I strongly suggest that you use the Amp Maker colour scheme shown in the photos and diagrams on this site to avoid any confusion. Every amp builder has their own preference, and some just go with what Fender or Marshall has used in the past. I've seen some amps which use the same colour for every single wire! If you do opt for your own wiring colour scheme, it's a good idea to print out the first photo (the underside of the board with no wires attached) and annotate it with the colours of the wires that you use for each of the connections.
      NOTE: Before proceeding to the next stage, double-check that you have all these under-board connections made. Remember to include the one wire which has both ends soldered to a turret bottom - the orange wire that runs past Point A in the above diagram.
Soldering to the underside of turrets
Soldering to the turret's underside is much the same as soldering to the turret top. The same principles apply, so make sure that you get a good shiny and seamless solder joint. In addition, watch out for the following:
* Errant wire 'whiskers' - the wires have 16 individual strands, and it's important to make sure that the strands of each and every wire sit in their own turret hole. Work in bright lighting so that you can easily spot any strands that stick out. These 'whiskers' can short the connection to adjacent turrets, or to the chassis.
* Overheated wire insulation - if you inadvertently melt the PVC insulation as you solder the joint, check to see if there's any exposed wire. If there is, it may short against other turrets or the chassis. Be your own worst critic, and if you're in any doubt, desolder the offending wire and try again.
* Soldering order - where the orange wire runs close to the turret that takes the red wire (point A in the diagram), it's best to solder the red wire first. If you solder the red wire after the orange wire, you risk melting the insulation of the orange wire.
* One turret, two wires - one of the turret's undersides must take two wires (the yellow and orange wires that meet at Point B in the diagram). Twist the strands of the two wires together before inserting them into the turret hole.

  WF-55 construction guide
  1 - Kit contents
  2 - Block diagram
  3 - Reading your schematic
  4 - Chassis assembly
  5 - Turret board assembly
  6 - Turret board wiring
  7 - Chassis wiring guide I
  8 - Chassis wiring guide II
  9 - Chassis wiring guide III
  10 - Initial testing
  11 - Final test

  WF-55 kit purchase page

  WF-55 construction guide
  1 - Kit contents
  2 - Block diagram
  3 - Reading your schematic
  4 - Chassis assembly
  5 - Turret board assembly
  6 - Turret board wiring
  7 - Chassis wiring guide I
  8 - Chassis wiring guide II
  9 - Chassis wiring guide III
  10 - Initial testing
  11 - Final test

  WF-55 kit purchase page