Hakko 936 discontinued, viable replacements? - Page 2

Another vote for a true temperature-regulated iron--the OKI PS-series are good, and the older MX- series power supplies can still be found for a good deal (some are compatible with modern wands; total cost < $150 for old power supply + new wand assembly).  Good variety of tips available.

Stations like the Hakko don't control temperature.  Rather, the pot determines the amount of heat flow to the tip--constant heat, variable temperature.  Curie-point systems use a variable amount of heat to produce a constant-temperature tip...which is usually what you want for sensitive electronics.  Of course, in many situations, having precise temperature control and minimizing heat transfer doesn't matter much.

Quote:

Originally Posted by cyberspyder 

Is it just me or does the 888 look kinds ugly?
 

it's fugly.  they should have called it an iHakko.  my 936 is my most valued DIY tool.

Silly Hakok users. I'll be over here enjoying my WES51.

Actually I would have bought the Hakko (and saved myself $30 or so) if they weren't sold out locally. They literally sold out 3 days before I went in to grab an iron. I was considering the ones on eBay (cantonmade), but as far as I can tell, they're all fakes (cantonmade) or unobtainable in Canada (American sellers who don't like doing paper work).

I'll take the design of the 936 with the performance of the 888. Much prefer the solid, hefty looking black box over the glossy "looks like it's going to fall over" egg timer.

The Blue-and-Yellow FX-888 remined me a lot of the FX-951 I have.

As for the 936, as so many others have said before, it'll have plenty of parts available for years to come, as there are plenty of these units out there. Probably the best value for money soldering iron you can buy. After working on one of these (or any other good quality iron for that matter), you're gonna ask yourself "how did I solder things before that", as it makes things so much easier and faster with very little effort.

Quote:

Originally Posted by Omega 

Stations like the Hakko don't control temperature.  Rather, the pot determines the amount of heat flow to the tip--constant heat, variable temperature.  Curie-point systems use a variable amount of heat to produce a constant-temperature tip...which is usually what you want for sensitive electronics.  Of course, in many situations, having precise temperature control and minimizing heat transfer doesn't matter much.

You sure? The heater indicator light exhibits behaviour of a proper temperature control...... just sitting idle, the heater light flashes only briefly. Hit a big joint, it comes on solid.

Eh, semantics between heat (quantity of thermal energy) and temperature (average kinetic energy in the ensemble), I guess...too many thermo classes ;).  The light behavior you describe sounds like it could be indicating heat flow too (rather than temperature).

It's a simple feedback, I believe?  The iron modulates current into the resistive element, pumping heat into the tip.  So the "constant temperature" of the iron is dependent on the dynamics of the electronic control circuit and the ability of the power supply to source current. No doubt it maintains a relatively constant temperature for a constant pot value and equilibrium environment at the tip.  The Curie effect irons are physically constrained to operate at a given temperature...they cannot do otherwise.  Current goes to the tip, which is made of a particular alloy.  When that alloy hits the design temperature, it demagnetizes and ceases to be resistive, heating stops.  Power supplies are beefy, temperatures are solid.  Thermally regulated irons must try to find the right balance in the thermal equilibrium.  Curie effect irons can just clamp up against the physical limit and dump current whenever the tip temp drops and picks up a magnetization.  Very elegant; they're awesome.  They can't overheat the tip, but can dump a huge amount of heat through the tip.

We could do a simple test to show for sure!  Hold the pot (ie, current source) constant and vary the thermal load.  If you put a heatsink on the tip of a Hakko 936 or similar, and measure the temperature with reasonable accuracy (ie, via decent thermocouple or laser thermometer), call it T(1).   Change the value of the heatsink and leave the pot at the same position, call that temp T(2).  If T(1) = T(2), it's controlling temperature reasonably well.  If T(1) ~ T(2) as a function of the heat flowing to the heatsink (proportional to the dissipation value), then the iron is just pumping heat without regard to temperature.  I actually did this on accident when I first got the Metcal.  I was soldering some fat solid core copper wire (12 ga or something awful).  I wasn't used to the new iron, and thought something was broken when I was just exceeding the ability of the power supply to source current.  So I did a test with lengths of copper.  Steady temps (at the tip) until the length got too long.

I've moved recently so finding a scrap heatsink is non-trivial...but I'll try to reproduce something for my Metcal with 650 tip...maybe another short pad of copper or something. I have a cheapie laser thermometer that should be reasonably accurate at hot temps. If you do it for a Hakko or similar, we can compare...will be interesting!

Edit: doh!  Forgot to quote.  Was responding to Beefy's post directly above.

The first time you dowse that super compressed sponge is wicked cool.

The 888 looks like the Danelectro Edition; or maybe Eddie Current/Laconic Edition.

Just bought a Hakko 936, as well as a PanaVise circuit holder. Yes, overkill for a newbie.... I know....

If I don't fry my fingers first, I will be building a CMoy first.