Re: Things I would do differently when I next build a K2

[Cathy James]

Bob N5BZ wrote:

> Subject: [Elecraft] Things I would do differently when I next build a K2
>
> These are things I would do in the future, that I did NOT do this time:
>
> 4) I would use a small piece of perf board and mount it in a handy vice.
> and use it to 'guage' the lead length to 'pre cut' the leads on most
> parts 'to length'. I would also use it to make sure the leads were
> pre-formed to the proper width. (perhaps Elecraft could include a scrap
> of board with each kit that has all the normal hole spacings.)
>  

I never found this necessary.  Just hold the part above the spot on the
PC board where it will be mounted and eyeball the spacing between
holes.  Usually the spacing for axial components is just right for you
to bend the leads just a little bit beyond the point where it joins the
body of the part.  In a few cases, the spacing is much wider.  For these
latter case, do the eyeball measurement, bend one lead 90 degrees at an
estimated point, then put the part in the hole without soldering.  Now
you can tell exactly where to put the other bend.
> 4a) I would catch and collect each lead as cut, so that I would NOT have
> to crawl around later and dig them out of the carpet. Finding hundreds
> of small pieces of wire is very difficult. (Hint: stepping on a lead can
> lead to some very unpleasant moments). I am NOT sure I will EVER find
> them all!
>  
This is very easy.  Hold the board in one hand and the cutting dikes in
the other.  With the extra lead side of the board up, carefully put the
cutters in the right spot on the wire, flush against the board.  Squeeze
them *very* gently, just enough to hold them in place on the wire but
not enough to cut through.  Now maintain this pressure and flip the
board upside down, directly over the trash can (you do have a small one
by your work area, I trust).  With the board upside down and the leads
directly over the trash can, squeeze harder.  The lead goes into the can
pretty much 100% of the time and is never anywhere near your eyes.

If you empty this trash can regularly and use it only for trash
generated in the course of building circuits, it will never have much
trash in it and you can easily rummage around in the bottom to find a
spare lead for grounding crystals or forming jumpers.  Be sure to line
the trash can with plastic grocery store bags before using.
> 5) I would place and solder one part at a time. The confusing of a
> forest of leads can cause one to miss soldering some.
>  
I haven't found this to be an issue.  Just triple-check that the lead
you are about to cut has been soldered.  Never, ever cut a lead before
soldering THAT LEAD.  It really doesn't matter if there is a forest of
other unsoldered, uncut leads around it.
> 7) I would triple check to make sure everything was correct before
> installing each part. It is MUCH easier to get it right-the first time-
> than to find a mistake and correct it later.
>  
This is the single most important piece of advice.
> 8) I would take a 10 minute break after each 50 minutes of work and NOT
> work late into the night.
>  
I rarely work more than 1 hour at a sitting.  At MOST, 2 hours.  The
project is best spread out over time without trying to do too much at
once.  And if you find that you are already tired when you sit down at
the workstation, skip your Elecraft-building session that night.  It
isn't worth the substantial risk of time-consuming mistakes.  Build
something simpler instead, or read ahead in the builder's manual without
actually building, or go do something else.
> 10) I would have the Radio Shack 'desoldering iron' with red rubber bulb
> handy and ready. I didn't buy one until after I had built my K2.
>  
I have an el cheapo desoldering bulb which I've found to be nearly
useless.  By far the best desoldering technique I have tried is to use
the regular temperature-controlled soldering station and copious amounts
of desoldering braid from Radio Shack.  Suck up as much solder as you
possible can from each joint and you should not have much trouble
getting the part out.  Do repeated short applications of heat, not one
long one.  Cut the solder-full desoldering braid with cutting dikes
every time you use 1/4" or so of it so that the end is always bare copper.

But the best solution to desoldering is definitely #7 above.  I was
very, very careful to check everything and I think I only desoldered two
parts in the whole K2 + SSB build process.
> b) I wind a coil of about 100 or 200 grams of solder (a nickel weighs 5
> grams, so half a roll or a roll of nickels in weight) around a Phillips
> screw driver shaft, rolling it neatly and carefully with many layers of
> solder.
>  
I've never felt the need for this.  I leave the heavy roll of solding
sitting on the desk in front of me, and unroll a few feet of it.  Hold
the loose solder (not the whole roll) in the hand that doesn't hold the
iron.  You can get very sensitive control of it.  (When using
heavy-gauge solder on larger objects, such as soldering coax to
connectors, I do just the opposite--unroll just a few inches of stiff
solder from the roll, and hold the roll instead of the solder.)
> c) A couple of pairs of hemostats are, of course, necessary for putting
> tension on the leads of the toroids. With the handle of my diagonal
> cutters for a fulcrum, the weight of the hemostats is just about right
> for giving the needed tension.
I don't see the point of this.  Winding toroids is very easy, if
somewhat tedious.  For each winding, *gently* pull the wire snug, then
go onto the next.  I've had no problems with this technique.  The little
FT37-43's probably offer the greatest risk of snapping the wire or
accidentally scraping off the insulation.  With the larger toriod cores,
the edges are less sharp.

Cathy
N5WVR

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