K7QO's PCB Enclosue Tutorial Page
PCB Enclosure Tutorial (Started March 14,2010)
Last Updated March 10, 2010
Question was asked on qrp-tech@yahoogroups.com about making PCB enclosures.
So, here is an almost complete tutorial on how I do it. The intital investment of
one hundred American dollars will more than make up for itself over the years as
you need more and more 'boxes' to put test equipment, receivers, transmitters, transceivers,
and anything else that you build into an enclosure.
Here is the list of the stuff used here and an approximate cost and a link where
appropriate. If there is something that you don't know, google the Internet to find
out all the gory details.
Harbor Freight Shear. Harbor Freight Shear URL.
Carpenter Square.
Graph Paper. I like 5 squares per inch as it matches PCB spacing pretty well for mounting holes. This due to
the PCB software commonly available for free on the Internet.
PCB Material. I get mine from a vendor 'abcfab' on ebay.com. Let's hope that he stays in business
and can keep getting the material and I'm hoping that not too many of you put him in overload and
drive up the pricing. Tell him I sent you, or not.
URL to abcfab
SWL-30+.I found this xcvr in a plastic container. I built
this thing so long ago I don't remember hiding it. So, let's put it in an enclosure and fire
it up.
PCB Material.Here is photo of some FR-4 (flame retardant) PCB material.
It is single sided with 2oz copper plating (2oz/sq ft). When I buy the material from abcfab, I seal
it in plastic to protect the surface from further oxidation and I label for quick reference when I
am looking for something in particular. I am probably one of his top 10 customers. :-)
SWL sitting on board.Here I have the SWL xcvr sitting on the board
to size it up.
Paper Template for Drilling and Layout. I took the graph paper and drew an outline of the board and the
center points of the four mounting holes. I cut this out and tape it to the PCB where I want the
board to be mounted. Then using the shear, I cut the board to size.
PCB in Shear.
Xcvr on Graph Paper and the PCB.
Standoffs and Screws.Here are some small threaded standoffs that I've
had for years in a pill bottle. Got them at HamCom in Dallas over 10 years ago.
Standoffs Mounted to PCB.This after I drilled the board and cleaned it in
the garage.
SWL on Standoffs mounted to PCB.
Now get some more material and cut two end pieces for the enclosure. A couple of points.
One. Make sure they are the same size and the width matches as close as possible to the base.
This makes cleanup and touchup simplier. You'll learn it from me or from making errors and
having to redo it.
End Pieces.
You know what makes this easy for me to do? I go ahead and layout and drill the front
panel and rear panels before I solder them to the base. Because I am using single sided
board here, it is important to remember that the copper side is INSIDE the case, so if
you drill from the copper side the layout will be reversed. Just make the template and
drill from the bare FR-4 material side. Makes it easier to understand.
Rear Panel.This piece will become the rear panel of the
enclosure. Holes for keyer jack, power and BNC connector for antenna.
Rear Panel and Base clamped to Fixture.This is a fixture that
I made of scrap boards to make a corner where all the angles are 90.000 degrees. OK. At
least as close as I could get them. I used 1/4" MDF (medium density fiber) board, but
any scrap material will work. Titebond II for the glue. You can't have too many
clamps.
Soldered Panel to Base.I used a ruler and penciled in equally
spaced points to solder. Do not solder close to the edge as another piece goes there.
Corner Piece Held in Place. Here I use a piece of scrap
PCB to put pressure to hold the corner piece in place in order to solder. This is important
if you really want things to turn out right.
Piece Now Soldered into place. I learned something here. Wait
between soldering points in order to allow the iron to heat back up to its high temperature.
With large heat sinking surfaces, the iron tip will cool down too much to make
each solder joint pretty.
Other corner piece soldered into place.Note: that by waiting
between points the iron reheated and allowed me to do neater solder joints.
Right Angle. Here a carpenters square shows us that the
rear panel and the base do form a right angle.
Rear Panel in Place.
Now repeat the process for the front panel. Drill holes for the two variable resistors
and one for headphone jack. I prefer my earphones to plug in the front instead of the
rear. That way I don't make too many mistakes plugging the iambic paddle into the
wrong location and the same for the headphones.
Finished Soldered Half of Enclosure.
Finished Soldered Half of Enclosure.