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Subject: Re: [Homebrew_PCBs] Source for solder paste squeegees?

From: Philip Pemberton <ygroups@...>
Date: 2010-11-19

On 19/11/10 05:26, DJ Delorie wrote:
> Couple of things to try...
[...]

Fixed it!

I made a squeegee out of a sheet of K&S 2mm aluminium sheet (cut in
half), a piece of 0.001" spring steel and some M4 machine screws.

And now for the Fool's Guide to doing this (if you're as crazy as I am):

- Cut your piece of aluminium in half. You should now have two
pieces, each around 5" square.
- Cut a strip of spring steel to the same width as your aluminium sheets.
- Measure the width of your spring steel. Mine was 1" wide.
- Measure half that distance up from the bottom of the aluminium
sheets, and draw a line.
- Draw crosses on that line one inch from each edge of the alu sheet,
and one cross in the middle.
- Drill holes where the crosses are, using a 4mm bit. Do the same for
both sheets. De-burr the holes and make them level with the rest of the
metal (hint: a countersink works wonders for this!)
- Stick a piece of masking tape over the edge of each sheet of alu.
- Insert the screws and screw them onto the nuts, but leave them
slightly loose (finger tight is more than enough).
- Insert the spring steel strip into the gap between the two sheets
of aluminium, on the side nearest the screws (where the masking tape
is). Tighten the screws with a screwdriver and bull-nose (electrician's)
pliers.

Now I need to figure out why I'm getting solder bridges in between my
QFP pads... :(

--
Phil.
ygroups@...
http://www.philpem.me.uk/