[Elecraft] RE: soldering iron recommendations

[Don Brown]

Hi

This question seems to come up from time to time. I have used many types =
of irons over the years. The Weller WTCP iron has been my weapon of choic=
e for over 20 years and I have 3 of them. However Weller has reduced the =
price of the WES50 to $99 twenty bucks less than the WTCP. I bought a WES=
50 about 2 years ago and I like it much better than the WTCP. Both irons =
are 50 watts and have the same selection of tips (although they are diffe=
rent). The WES50 has a knob on the base to adjust the temperature while t=
he WTCP you change the tips for different temps. The WES50 will also turn=
 itself off after 99 minutes of no use to save burning up tips. Either un=
it will work fine if the proper tip is used, for the K2 or KPA100.

That brings me to tips and I have used most of them. For most work the PT=
A7 or ETA is the best choice. Less than 700 degrees is not enough heat an=
d you will burn up parts and lift pads because you need to stay on the jo=
int too long. 800 degrees will burn up parts and lift PC pads because its=
 is too hot (it is good for stripping torroid wire though). I usually run=
 my WES50 at 750 degrees but I have been doing this a long time and like =
a little more heat and less time on the joint to speed up the work. I wou=
ld recommend setting the WES50 at 700 degrees for most work and 800-850 f=
or stripping wire. Just remember to turn it down when you go back to sold=
ering.

I don't recommend the long reach tips like the ETS or the narrow tips lik=
e the ETR. These tips look good but they don't have enough mass to transf=
er the heat from the heater to the joint. To put it in electrical terms t=
hink of the heater as a battery the tip as a resistor and the joint as th=
e load. A thin narrow tip is like a high value resistor and a short fat t=
ip is like a low value resistor. Short fat gets more heat to the load qui=
cker because of less resistance. Short fat also holds more heat so the ti=
p does not cool as much before the heater can bring it back up to the set=
 temperature between joints. The only downside to the short fat tips is y=
ou need to be very careful not to burn or melt parts when working in clos=
e quarters.

For the heavy work in the KPA100 change to a PTD7, PTH7 or ETD, ETH and c=
rank up the WES50 to 750 degrees. I had no problems soldering the large t=
ransformers or RF transistors with my WES50 and a large tip. Of course if=
 you have a big 200 watt gun or 100 watt iron you can use it on the heavy=
 joints in the KPA100. Just don't go buy one to do the KPA100 when a larg=
e tip for $6 or $7 will do the job in your solder station. =20

Don Brown
KD5NDB

As usual no affiliation with Weller JMHO and 35 years experience using th=
eir stuff.

tip selection chart for WES50:

http://www.action-electronics.com/pdf/et.pdf



From: "Chuck Roedel" <CR@captainoftheclouds.com>
To: "elecraft L-serve" <elecraft@mailman.qth.net>
Date: Tue, 14 May 2002 11:14:19 -0400
Subject: [Elecraft] soldering iron recommendations

Hello to everyone,

I used a Weller WTCPT for soldering my K2 and accessories .I see in the =3D
KPA100 manual the final transistors must be soldered in with a higher =3D
wattage iron than what's used for assembling the rest of the unit.=3D20
What would be a good iron to purchase for this task?


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