Economical Electronic Inline Temperature Controls for PCB soldering irons.

[ToddB66]

Hi

I've just recently become interested in electronics and my first project is building a Velleman metal detector kit #K7102 that involves soldering components to a PCB. After completing the solder work on the PCB, I plan to mount it in a plastic control box and glue the coil inside the front end of a plastic tube for the probe, to make a pinpointer. To date, I have no experience soldering components on a PCB. 　

I have two soldering irons used in the past for small work before I became interested in electronics. One is a Radio Shack no. 64-2051, 15 Watt Grounded, with pencil tip and the other is a Weller Marksman no. SP-40, 40 Watt, currently wearing a standard chisel tip, which I would replace with a pencil tip if used for PCB work.

I've been trying to "gulp down" enough information from the Internet to have a fighting chance of successfully soldering components on a PCB. One of the first websites I found was Howard Electronic Instruments, Inc. and there is a page titled Chip Quik SMD Removal System that taught me a lot. One thing was the importance of soldering iron temperature control. Different soldering applications require a certain heat temperature to make good connections and reasons/details were given.

Does anyone know of an economical temperature control device that I could buy or build myself that would connect inline to my irons ? Years ago I bought a 110V/20Amp Speed Control device that has dial settings from 1 to 10, to use with my router in woodworking. This speed control device didn't come with a circuit drawing, so not sure, but assume it works similar to a rheostat. Is there a chance that my speed control device could be used to control soldering iron temperature ? If so, does anyone know of an economical device that I could buy or build to use in conjunction with my speed control to know what temperature is being provided at the soldering tip, rather than going by "trial & error ?

If I build my own temperature control device(s), I would need the kind offer of someone to provide me with circuit drawing(s).

I know this post gives readers a lot to digest and try to come up with answers and advice, so thanks in advance for any help you can offer !

ToddB66

[muddy fingers]

I've done a fair amount of soldering involving electrical components inside metal detectors and I know that things would have been much easier if I'd paid the extra cost of getting a proper temperature controlled soldering iron in the first place. To solder successfully, quite a few things need to be taken into consideration and I would recommend that you read some little books that are published on the subject.

[joop]

I own both a Weller and Velleman soldering station. Both are temperature controlled and perform the same, but the Velleman is 3 times cheaper. I always have the setting at 350 degrees (Celcius) and never touch the temperature setting. Don't know if the speed control will work with your Weller, since the soldering iron itself might be temperature controlled.

[Davor]

I've got a magnastat soldering iron. The most primitive, the most accurate, and the most predictable regulation one can think of. Can't beat the physics.

[Thomas]

A 15 W will do 90% of what you need, the 40 W will fix the big stuff. The most important thing is to learn how to use it. Practice soldering wire to an old scrap board, remember it's heat that melts solder, not pressure.
I mainly use a Radio Shack 15 W for everything, make sure you have everything set up correctly before you start, so that when you start to solder you can go like you are on an assembly line. that is because the tip of the iron will start to oxidize and thats when problems start. Practice, Practice, Practice.

I can not delete the attachment ?

[Silver Dollar]

There's generally 3 or 4 different temperatures you might use 650, 700, 750, 800 degrees F. I usually use one
most of the time (700 - 750) but sometimes need more heat so go up to the 800 or have special caps that are
low drift and made out of solder and plastic sheets that require very low heat so use 650.

For most work you can use a pencil iron and have a trigger gun type for the high heat work. More important is
the tip and heat regulation. Better irons have a magnet switch in them that turns on and off holding a set
temperature. Tiny tips 1/32" are needed for SMT work. Keep your tip tinned and don't forget to shut it off
when your done using it!

[migusch]

Hi, ToddB66!
I have to back up with Thomas - there seems to be too much theoretical science in your approach...
No need to have 'perfect' equipment when it is time to get some practical knowledge and hone your handcraft skills (unless you want to start soldering as your day job)
Just take some scrap-PCBs from consumer electronics and desolder some components. Resolder them on perfboard or back again on the original PCBs and you will gain the skills you need for your MD-projects. You will get faster and more accurate with the time and you will burn yourself less frequently the more you practise.
I myself use the exact same solder irons like you (regarding wattage) without any temperature control and those two worked just fine for me for more than 25 years and countless projects.

Anyway - every electronical dimmer for lightbulbs (resistive load) with proper range of wattage will probably do the job if you hold on the idea of setting the electrical power of the soldering iron.

[ToddB66]

Economical Electronic Inline Temperature Controls for PCB soldering irons.

Thanks to all who replied to my subject post. Your advice, etc. was very helpful !

I respect the fact that some of you have had good results with the economical non- temperature controlled irons, like the Radio Shack 15 watt Grounded model 64-2051 that was selling for around $8.00 and tax when I bought mine in 2006. This soldering iron has a 1/32" pencil tip and the price has gone up to $12.00 - $13.00 on the RS website.

However, for those of you, like myself, who would prefer a temperature controlled soldering iron, I found an economical soldering station on Amazon, the Aoyue 937 + Digital Soldering Station, that has temperature control accuracy of +/- 1 deg. Celsius (+/- 33.8 deg. Fahrenheit), with a spare element and Free Shipping for $63.99. If you need finer accuracy, the cost goes up of course.

Have any of you owned and used the Aoyue 937 + and what is your opinion of this unit ?

Thanks again for your opinions and advice.

ToddB66