I know this a double post, posted under Project.., but my questions concerns both repair and a new project idea.
My questions is three questions. I like to build my own equipment to save money and I need a new soldering station or at least a handle. I don't like the $100-$150 price of a new Hakko station when I think I can use the old parts left over from my dying station to make my own if I buy a good handle. After 14-years, my old analog handle is falling apart, even though the first handle lasted for 7-years and the second tip in the replacement handle is still well-tinned and working fine.
Fact 1: I must build my own controller, the old iron used a thermistor instead of a thermocouple for temp sensing. I assume the Hakko models all use a thermocouple for sensing.
Question 1:
Does anyone know if what vendor of Hakko soldering handles selling for less than $10 on Ebay are the real thing?
Do they have silicone cables and Hakko ceramic elements. They look like the real thing.
Question 2:
Are Hakko soldering tips long-lasting and easy to buy? Always a problem with soldering handles: the availability, life and price of replacement nibs. My old soldering handle tip has lasted 14-yrs even though I did tons of removing old parts from salvaged equipment and built all my many projects with it! Before that I had a Weller TCP station that would lose its tining quick, I used up a tip a month just because I left the iron on, not even using it most of the time, while I worked on my projects.
Question 3: How hard could it be to breadboard a temperature controller using the thermocouple output of the handle?
Should be easy to make my own soldering station with the transformer left over from my dying analog soldering station.
I think I can I think I can!
I need a Hakko schematic.
It seems all I need to do is breadboard a thermocouple amplifier, gain of two series op amps approx 500, even just using a LM358 amplifier and then feed the output to A2D input on my PIC 10-bit A2D MCU, and with a stable reference of the PIC A2D I should be able to adjust the on/off time based on low/above temperature of the iron tip thermocouple. I then shut off the PWM or phase control of the heating element, wait a few millisecs and get a reading every tenth of a sec.
After all, soldering is a little like cooking, soldering does not need to keep the temperature precisely at the melting point, a few degrees above and dithering about should work, or so I think!
I have bouht a thermocouple type replacement generic analog handle(sans controller, I bought it because I just needed the handle parts to repair my old crumbled handle) and I see about 7mV of output voltage(just needs a little amplification before a2d'ing it) around the melting point of eutectic Pb-Sn solder, so what's the problem to get something to work with a simple pot to adjust the tip temperature?
What about this one?
http://www.ebay.com/itm/FM2028-24V-70W-Soldering-Iron-Handle-for-Solder-Station-FX-951-Eesy-replace-/291335240078?pt=LH_DefaultDomain_0&hash=item43d4eef98eOr this one?
http://www.ebay.com/itm/HAKKO907-Soldering-Station-Iron-Handle-Soldering-TIPS-Welding-cleaning-sponge-/181571139172?pt=LH_DefaultDomain_0&hash=item2a467bb664