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WF-55 Chassis assembly



This page shows how to use the pre-punched chassis that comes with the Time saver version of the WF-55. If you bought the Basic version, you will have your own chassis (instead of the pre-punched chassis shown above). You will need to prepare it as you go. Use these pictures as a general guide.

Power transformer

The power transformer mounts through the large rectangular cut-out that's surrounded by four M4 screw holes. To fit it, undo the four nuts and remove the fixing hardware from the underside: one steel locking washer, one plain steel washer and then the red fibre washer. Mount the transformer on the chassis' top surface, sliding the solder lugs through the rectangular hole and replace all of the fixing hardware in the same order. So the red fibre washer will sit on the chassis, then the plain steel washer fits on top of that, then the steel locking washer and finally the nut. Tighten the four nuts fully.
      The power transformer can go either way around, but it's probably best to have the mains-related solder lugs (0-120 and 0-120) closer to the side of the chassis. This makes for slightly neater cable runs.

Output transformer

The output transformer runs across the chassis, behind the power transformer. To mount the output transformer, there are two 4mm holes; use M4 screws, shakeproof washers and nuts, and make sure that this transformer's lugs face towards the power transformer, as shown in the photo (right). Then fit a rubber grommet to the 10mm hole just to the side of the output transformer.

Valve sockets

The pre-punched chassis has two sockets. Add the 9-pin valve socket to the position close to the front panel, using the two M2.5 screws and nuts with M3 shakeproof washers to secure the base of the valve shield.
      The octal socket mounts in the larger hole. The socket and mounting ring go on the inside of the chassis, and the retaining clip goes on the outside of the chassis (see below). Use M3 hardware to mount this socket - it can be a bit fiddly to align the mounting ring and retainer but persevere! :)


Front and rear panel

Before adding any of the front or rear panel components, decide what you want to do with your front panel (see Front and rear panels, right). Once you've finished your front panel, mount it with the input jack socket, Volume pot and neon indicator. Then add the power switch, mains socket and speaker jack socket on the back panel. When aligning the controls make sure you'll be able to get to the lugs for soldering later!
      The pot is a general purpose type, and there are a couple of adjustments to make. First, bend back the small forward-projecting tab so that the pot can sit flush against the chassis. Then trim the soft nylon shaft of the Volume pot - use a Dremel-type tool or junior hacksaw to cut it down to about 8-10mm. Now, fit the chickenhead knob; rotating it so that when the pot is set fully clockwise, the pointer is at about 5-o'clock. Fix it by tightening the knob's set screw.
      For the On/Off switch, align it so that the 'On' label on the switchplate is uppermost. And for the combined IEC/fuseholder, make sure the Earth lug is uppermost. Insert the 500mA fuse into the holder in the fuse tray and slide it into place (you'll feel it click into the socket's internal fuse contacts).

Solder lugs for grounding

Both grounding lugs are secured with M4 screw, shakeproof washer and nut. The first is close to the mains socket, and the second is close to the rubber grommet you've already added.
      For each solder lug, bend them so that the 'arm' is pointing upwards - you'll use this to solder when you add the wiring.
Front and rear panels

The Time saver kit comes with a plain mahogany front panel. Before mounting it (with the input socket, Volume control and neon indicator) you need to decide what sort of look you want, and how you want to finish it. You have a huge range of options. At the simplest, your local DIY shop has simple oil-based finishes, such as Danish oil and Tung oil. If you're feeling more adventurous, you can use one of the many finishes that guitar makers use, such as Gibson cherry red. The example here uses a subtle red dye shading and Danish oil.

      For the chassis' back panel, your kit comes with a legend sticker that fits between the mains socket and speaker socket. It shows the rear panel layout with space to write in the mains voltage, fuse rating (0.5A for the WF-55) and your chosen speaker impedance.


The PT mounts through the large rectangular hole on the chassis

Use M4 hardware to secure the output transformer, and add the rubber grommet for its wires


Mount the 9-pin valve socket using the shield base and M2.5 hardware



Orientate the On/Off switch and the combined fuseholder and mains input socket as shown here



The solder lugs are used for grounding, bend them so that they are accessible for soldering

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