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We stock 100's of Home Appliance Parts for all Brands, Makes and Models.
Whirlpool, Kenmore, Roper, KitchenAid, just to mention a few. We carry
clock timers, heater elements, oven sensors, timers, pumps, belts, switches,
burners and more for your Washer, Dryer, Refrigerator, Range, Oven,
Freezer, Microwave.
repair tip:
Soldering is a skill that is handy to know for many types of construction
and repair. For modern small appliances, it is less important than it
once
was as solderless connectors have virtually replaced solder for internal
wiring.
However, there are times where soldering is more convenient. Use of
the
proper technique is critical to reliability and safety. A good solder
connection is not just a bunch of wires and terminals with solder dribbled
over them. When done correctly, the solder actually bonds to the surface
of the metal (usually copper) parts.
Effective soldering is by no means difficult but some practice may
be needed
to perfect your technique.
The following guidelines will assure reliable solder joints:
* Only use rosin core solder (e.g., 60/40 tin/lead) for electronics
work.
A 1 pound spool will last a long time and costs about $10. Suggested
diameter is .030 to .060 inches for appliances. The smaller size is
preferred as it will be useful for other types of precision electronics
repairs or construction as well. The rosin is used as a flux to clean
the metal surface to assure a secure bond. NEVER use acid core solder
or the stuff used to sweat copper pipes! The flux is corrosive and
it is not possible to adequately clean up the connections afterward
to
remove all residue.
* Keep the tip of the soldering iron or gun clean and tinned. Buy tips
that
are permanently tinned - they are coated and will outlast countless
normal
copper tips. A quick wipe on a wet sponge when hot and a bit of solder
and they will be as good as new for a long time. (These should never
be
filed or sanded).
* Make sure every part to be soldered - terminal, wire, component leads
-
is free of any surface film, insulation, or oxidation. Fine sandpaper
or
an Xacto knife may be used, for example, to clean the surfaces. The
secret
to a good solder joint is to make sure everything is perfectly clean
and shiny and not depend on the flux alone to accomplish this. Just
make
sure the scrapings are cleared away so they don't cause short circuits.
* Start with a strong mechanical joint. Don't depend on the solder
to
hold the connection together. If possible, loop each wire or component
lead through the hole in the terminal. If there is no hole, wrap them
once around the terminal. Gently anchor them with a pair of needlenose
pliers.
* Use a properly sized soldering iron or gun: 20-25 W iron for fine
circuit
board work; 25-50 W iron for general soldering of terminals and wires
and power circuit boards; 100-200 W soldering gun for chassis and large
area circuit planes. With a properly sized iron or gun, the task will
be
fast - 1 to 2 seconds for a typical connection - and will result in
little
or no damage to the circuit board, plastic switch housings, insulation,
etc. Large soldering jobs will take longer but no more than 5 to 10
seconds for a large expanse of copper. If it is taking too long, your
iron is undersized for the task, is dirty, or has not reached operating
temperature. For appliance work there is no need for a fancy soldering
station - a less than $10 soldering iron or $25 soldering gun as
appropriate will be all that is required.
* Heat the parts to be soldered, not the solder. Touch the end of the
solder
to the parts, not the soldering iron or gun. Once the terminal, wires,
or component leads are hot, the solder will flow via capillary action,
fill
all voids, and make a secure mechanical and electrical bond. Sometimes,
applying a little from each side will more effectively reach all nooks
and crannies.
* Don't overdo it. Only enough solder is needed to fill all voids.
The
resulting surface should be concave between the wires and terminal,
not
bulging with excess solder.
* Keep everything absolutely still for the few seconds it takes the
solder
to solidify. Otherwise, you will end up with a bad connection - what
is
called a 'cold solder joint'.
* A good solder connection will be quite shiny - not dull gray or granular.
If your result is less than perfect reheat it and add a bit of new solder
with flux to help it reflow.
Practice on some scrap wire and electronic parts. It should take you
about
3 minutes to master the technique!
Occasionally, it will be necessary to remove solder - either excess
or
to replace wires or components. A variety of tools are available for
this purpose. The one I recommend is a vacuum solder pump called
'SoldaPullet' (about $20). Cock the pump, heat the joint to be cleared,
and press the trigger. Molten solder is sucked up into the barrel of
the
device leaving the terminal nearly free of solder. Then use a pair of
needlenose pliers and a dental pick to gently free the wires or component.
Other approaches that may be used in place of or in addition to this:
Solder Wick which is a copper braid that absorbs solder via capillary
action; rubber bulb type solder pumps, and motor driven vacuum solder
rework stations (pricey).
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