Board case

[Tony]

Once the main PCB frame is completed and tested it can be built into the base case.

Gently brush the top panel engravings to remove any loose dust. You'll need to fill the engravings to make them legible, I used white acrylic fabric paint as it was handy - you could try other colours or materials.

If there are any small scratches or you'd prefer a gloss finish the board can be polished with 'T-cut' or similar paint restorer before filling the engravings.

Rub the paint into the engravings, making sure they're filled and there are no air bubbles:



Leave to dry then rub off the excess paint, taking care not to remove too much from the engravings.

[Tony]

You'll first need to identify which side of the base panel is the top. Put the engraved top and the base panel together with the double-holes for the power connector to the left. Make sure all the bolt holes line up, if not turn the base panel round. When they line up you will have the top side facing you. Turn it so that side faces down.

Take the 26x M4x20 bolts from bag1 and fit them through the holes in the base panel and hold in place with masking tape.

Sand the paxolin spacers (you'll need 77 of them) and side strips, they'll need to be as flat as possible as the bolts are only just long enough.

Now turn over the board and put one paxolin spacer on each of the nine bolts in the centre.

Sort the pile of spacer strips into two lots - one with notches cut into them and one without. For the first layer you'll need 2 long and 2 short pieces with notches. Build it as shown here:

[Tony]

For the next layer you'll need the PCB side pieces, these are the 2 with 8 notches and 2 with one large notch. Fit these as shown:

[Tony]

Now drop the PCB frame into place and add another spacer to the 3 bolts top and bottom:

[Tony]

Now you'll need one long strip with a notch, two short with a notch and two half-strips with a notch.

Note that one half-strip is slighly shorter than the other as the power socket isn't quite in the middle:

[Tony]

Now do the same again with the no-notch pieces. You'll need 2 long, one short and 2 halves, again one slightly longer than the other:

[Tony]

Repeat with alternate layers of notch and no-notch strips:

[Tony]

Layer 6:



Layer 7:



Layer 8:

[Tony]

Layer 9 uses the last of the notch strips. Make sure you have 9 spacers on each of the top and bottom bolts, 7 on top of the PCB bolts left and right and 6 on the centre bolt:

[Tony]

Carefully push the coil frame sheet over the bolts:



You now have the 'fun' job of carefully bending the coil leads so each coil is in the middle of its' hole and level with the top of the frame:



This will require quite a lot of patience and repetitive work. The effective diameter of these coils is much smaller than the hand wound or printed ones and the piece needs to be placed directly over it and you'll need to try the top on a few times until you have it lined up correctly.

Once you have the coils aligned I would recommend using some thin strips of double sided tape to hold the frame and top sheets together for final assembly or better, remove the frame and carefully glue it to the underside of the board top. This will provide the most rigid finish and prevent any warping of the thinner laminate.

Put a washer over each bolt and hold it all in place with a dome nut. There won't be much thread to 'bite' onto so you may need to compress the strips a little until it does catch. Thumb-tighten them and the board should now be rigid.

Final rigidity is provided by the bolts holding the stacks of strips around the edges, once tightened there should be very little flexing of the board.