The Living Soldering Thread

[heedpantsnow]

What temp should I use on my Hakko for harvesting switches off a Cherry PCB?  Using a cheap soldapudt. Sorry Mkawa, didn't have enough left for one of your nice Edsyn's :-(

[heedpantsnow]

What temp should I use on my Hakko for harvesting switches off a Cherry PCB?  Using a cheap soldapudt. Sorry Mkawa, didn't have enough left for one of your nice Edsyn's :-(

Please help!

[phoenix1234]

What temp should I use on my Hakko for harvesting switches off a Cherry PCB?  Using a cheap soldapudt. Sorry Mkawa, didn't have enough left for one of your nice Edsyn's :-(

Please help!

If the switch was soldered with lead-solder, you can set around 320-330 °C (608-626 Fahrenheit) If the switch was soldered with lead-free-solder, you can set around 350 °C (662 Fahrenheit) However, you should not keep the soldering-iron on the switch legs longer than 3 seconds.

[heedpantsnow]

What temp should I use on my Hakko for harvesting switches off a Cherry PCB?  Using a cheap soldapudt. Sorry Mkawa, didn't have enough left for one of your nice Edsyn's :-(

Please help!

If the switch was soldered with lead-solder, you can set around 320-330 �C (608-626 Fahrenheit) If the switch was soldered with lead-free-solder, you can set around 350 �C (662 Fahrenheit) However, you should not keep the soldering-iron on the switch legs longer than 3 seconds.

Wow, awesome info.  Thank you so much good sir!

[platypus]

Hullo. I'm about to do a couple soldering projects for keyboard stuff (all throughhole components) but I've not soldered in over a year, and was never great at it to begin with. Any recommendations for cheap projects/kits I could put together as practice? Thanks

[mkawa]

desolder at the same temperature you would solder at, and add flux to strip the oxidization from the existing joint. soldering (processing) temperature again is:

for leaded solders: 350-375C

for unleaded solders: 450C

the processing temperature of a solder is actually more dependent on the flux in the solder and a bit less on the alloy (although the two are highly dependent on each other). those are general rules of thumb for popular solder and flux combinations. if you're having trouble bringing joints to liquidus (aka melting the solder onto the joint), turn up the temperature about 25C and add more flux.

one note: if you ever see carbon when you solder, you are burning the flux instead of evaporating it. turn your iron down about 25C at a time until it looks like you're boiling the flux off.

[heedpantsnow]

Thank you that is soooo helpful. Didn't know if the solder Cherry used is higher temp or if I run the risk of damaging something if I use too high.

[mkawa]

every modern product made on an assembly line is lead-free no-clean. peg the iron at 450c and add RA-type flux or something else equally effective (no-clean also means no-efficacy.. :/) to scrub the oxidization. if you don't have separate flux, add a bit of solder to the joint between desoldering attempts. the flux in the core of your fresh solder will help clean the joint, and the solder you add will distribute that flux into the old joint as it becomes molten.

on a scale of not-all-that-delicate to OMG DON'T BREATHE ON IT, cherry switches are much closer to indestructible than otherwise. the thing to remember about melting solder in general is that if you're not melting solder pretty much immediately, then it's not a problem of the heater on your iron not being hot enough, but thermal resistance between the heater and the soft metal in a solder joint. metal joints form an oxide skin and gather other impurities that cause them to become less thermally efficient and have other bizarre properties that you don't want when you're soldering and desoldering. this also goes for the solder on the tip of your iron.

there are two ways to clean up this suboptimal skin of oxide and impurities on metal. the first is mechanical abrasion. one of the most useful tools you can have in your soldering kit is a brass brush. these are fantastic for scrubbing old component legs and for when you accidentally burn plast^H^H^H skin^H^H^H your face with your iron tip. i tend to put a bit of solvent (eg, iso alcohol) on the brush then scrub. for your iron tip you can and should scrub the tip while hot. between vigorous scrubs, you should attempt to tin with fresh solder. a low quality tip will be extremely difficult to tin, so don't hurt yourself trying to scrub carbon and oxide off of your tip if you're using eg a cheaper asian knockoff iron.

the second method is flux. flux is a corrosive solvent that activates with the application of energy; that is, when exposed to oxide and power as heat, an endothermic reaction occurs that takes takes the oxide and flux components and produces a gas. (fun fact: that gas is what you smell when you solder, and is really the only potentially toxic thing involved in soldering; flux fumes are potent VOCs.) hence, flux flux and more flux. then heat. then more flux.

between two tinned surfaces, without any oxide, heat transfers pretty readily, and all parts that have a clear path to the heater will pretty much sit at the same temperature, which means that your parts and solder should heat more or less instantly to your heater temperature. _if this doesn't happen_, don't freak out and don't attempt to hold the tip to the parts for longer. instead, back up to the above and determine where the thermal resistance is, clear that resistance and then try again.

[jamster]

That was the best post I've ever read about why to use flux.

[heedpantsnow]

every modern product made on an assembly line is lead-free no-clean. peg the iron at 450c and add RA-type flux or something else equally effective (no-clean also means no-efficacy.. :/) to scrub the oxidization. if you don't have separate flux, add a bit of solder to the joint between desoldering attempts. the flux in the core of your fresh solder will help clean the joint, and the solder you add will distribute that flux into the old joint as it becomes molten.

on a scale of not-all-that-delicate to OMG DON'T BREATHE ON IT, cherry switches are much closer to indestructible than otherwise. the thing to remember about melting solder in general is that if you're not melting solder pretty much immediately, then it's not a problem of the heater on your iron not being hot enough, but thermal resistance between the heater and the soft metal in a solder joint. metal joints form an oxide skin and gather other impurities that cause them to become less thermally efficient and have other bizarre properties that you don't want when you're soldering and desoldering. this also goes for the solder on the tip of your iron.

there are two ways to clean up this suboptimal skin of oxide and impurities on metal. the first is mechanical abrasion. one of the most useful tools you can have in your soldering kit is a brass brush. these are fantastic for scrubbing old component legs and for when you accidentally burn plast^H^H^H skin^H^H^H your face with your iron tip. i tend to put a bit of solvent (eg, iso alcohol) on the brush then scrub. for your iron tip you can and should scrub the tip while hot. between vigorous scrubs, you should attempt to tin with fresh solder. a low quality tip will be extremely difficult to tin, so don't hurt yourself trying to scrub carbon and oxide off of your tip if you're using eg a cheaper asian knockoff iron.

the second method is flux. flux is a corrosive solvent that activates with the application of energy; that is, when exposed to oxide and power as heat, an endothermic reaction occurs that takes takes the oxide and flux components and produces a gas. (fun fact: that gas is what you smell when you solder, and is really the only potentially toxic thing involved in soldering; flux fumes are potent VOCs.) hence, flux flux and more flux. then heat. then more flux.

between two tinned surfaces, without any oxide, heat transfers pretty readily, and all parts that have a clear path to the heater will pretty much sit at the same temperature, which means that your parts and solder should heat more or less instantly to your heater temperature. _if this doesn't happen_, don't freak out and don't attempt to hold the tip to the parts for longer. instead, back up to the above and determine where the thermal resistance is, clear that resistance and then try again.

Amazingly helpful. I've learned so much just in the few minutes it took to read that (actually I read it like 4 times )!

[swill]

Nice posts mkawa (as always).  That one was very clear.

When desoldering I have taken to always just adding a little solder and then desoldering.  I tried a few different things, but this always worked perfectly, so I basically just do that all the time now.

[Parak]

desolder at the same temperature you would solder at, and add flux to strip the oxidization from the existing joint. soldering (processing) temperature again is:

for leaded solders: 350-375C

for unleaded solders: 450C

Thought I'd point out that lead-free does not actually require a higher temperature than a typical 350c or so, but merely that the iron/station is able to supply power faster to compensate for the slightly higher temperature of the alloy (~220c vs 183c) and the thermal load recovery required as the result. This generally means more wattage. Using high temperature on a low power iron is a hacky way of getting around the power issue, as the tip temperature dropping will still leave it at a decent soldering temperature, but this comes with some hefty downsides. Soldering and desoldering at such a high temperature will mean a much faster tip oxidation (particularly when combined with desoldering), PCB delamination, pad lifting, and higher chance of damaging components in question including thermoplastic melting, header pins sliding out, etc.

This is complicated a bit further by how well the controller of the iron is able to compensate as well as the tip heater technology used - for example, a JBC 2245 iron at 50 watts will run circles around a Hakko 888 at 65 watts even though both are resistance soldering. Metcals are even more interesting as far as how they deliver their power so effectively at a lower wattage, so that's a longer topic.

Regardless of how some higher end stations handle temperature and lead-free though, as long as one has a reasonable quality 70+ watt iron with a clean tip and flux where needed, soldering lead-free at regular temperatures should be fine. Unfortunately I can't make specific suggestions on lower end stations for soldering lead-free, as their tip/station/iron quality is way all over the map. Not very helpful, I know

[mkawa]

It's a bit more complicated than that, and the notion that processing temperatures are higher than alloy phase change only because of thermal recovery efficiency is a common misconception. I'll get into it later, but the basic idea is that the alloy and oxide will become molten at about the same time, and oxide within a joint or non uniform transition into the solidus phase results in joints with higher bulk defect rates and hence lower joint longevity. Lead free alloys are particularly prone to this phenomenon, hence the significantly higher processing temperatures.

[Bucake]

i was looking for a first soldering iron, and the edsyn 951sx looked good to me,
but why is the 230 version so much more expensive..? :/
http://www.edsyn.com/product/951SX.html ($163.60)
http://www.edsyn.com/product/951SX-230.html ($266.80)

[twiddle]

I have always felt it was a result of the economies of scale being smaller with the 220-240v versions, and the fact that the structure of the distribution networks tend to permit AU/EU customers being ripped off a bit more (things are the same here in Australia with any 240V soldering tools, I posted in this thread a while back about the Australian Hakko iron costing $200 instead of $100). There could be other factors at play too, I guess. Maybe others can shed additional light?

[Parak]

It's a bit more complicated than that, and the notion that processing temperatures are higher than alloy phase change only because of thermal recovery efficiency is a common misconception. I'll get into it later, but the basic idea is that the alloy and oxide will become molten at about the same time, and oxide within a joint or non uniform transition into the solidus phase results in joints with higher bulk defect rates and hence lower joint longevity. Lead free alloys are particularly prone to this phenomenon, hence the significantly higher processing temperatures.

Well, lead-free reflow parameters for example are typically about 40c higher than leaded reflow profiles at their peak - 260c (at most) compared to 220c, which corresponds well to the alloy melting point difference between the two. This is as per JEDEC J-STD-020D, but obviously proper reflow ovens have a lot of power and are able to maintain a particular temperature extremely well, not to mention that it's a radiant heat instead of point based and that the flux will already be there in the paste, it's fresh, and so on. Still, I'm quite opposed to the idea that using 450c for lead-free is needed, as it is definitely damaging to everything involved. If anything, I'd say that for proper lead free soldering at much lower temps folks should invest into a JBC, Pace, Metcal, etc, especially since it's possible to get a good deal on ebay for them at well below market prices.

[jamster]

I have always felt it was a result of the economies of scale being smaller with the 220-240v versions, and the fact that the structure of the distribution networks tend to permit AU/EU customers being ripped off a bit more (things are the same here in Australia with any 240V soldering tools, I posted in this thread a while back about the Australian Hakko iron costing $200 instead of $100). There could be other factors at play too, I guess. Maybe others can shed additional light?

I asked a professor at the Australian Graduate School of Management about jacked up prices in Australia vs markets like the US/EU. His short answer was basically that Australia is a small market where there are a small number of sellers (distributers) that excercise far greater control than in larger markets. So they jack up prices *because they can*.

So "economies of scale" don't really come into it. You nailed it with the distribution reason. It's basically market size and ologopolistic controls. Books ten years ago was a perfect example (I don't know what book prices are now). There was a cartel of 2-3 companies that controlled book distribution in Australia, which is why you had crazy prices like 20-30 for books that cost around 10 in the US.

Edit: Just realised this was a complete digression from the thread. Sorry about that.

[mkawa]

It's a bit more complicated than that, and the notion that processing temperatures are higher than alloy phase change only because of thermal recovery efficiency is a common misconception. I'll get into it later, but the basic idea is that the alloy and oxide will become molten at about the same time, and oxide within a joint or non uniform transition into the solidus phase results in joints with higher bulk defect rates and hence lower joint longevity. Lead free alloys are particularly prone to this phenomenon, hence the significantly higher processing temperatures.

Well, lead-free reflow parameters for example are typically about 40c higher than leaded reflow profiles at their peak - 260c (at most) compared to 220c, which corresponds well to the alloy melting point difference between the two. This is as per JEDEC J-STD-020D, but obviously proper reflow ovens have a lot of power and are able to maintain a particular temperature extremely well, not to mention that it's a radiant heat instead of point based and that the flux will already be there in the paste, it's fresh, and so on. Still, I'm quite opposed to the idea that using 450c for lead-free is needed, as it is definitely damaging to everything involved. If anything, I'd say that for proper lead free soldering at much lower temps folks should invest into a JBC, Pace, Metcal, etc, especially since it's possible to get a good deal on ebay for them at well below market prices.

making joints using anything other than a hot tip is a completely different animal and is not comparable to soldering with a hot tip iron and drawn wire. food for thought: why is the flux drawn into the axial center of the soldering wire? it would be a heck of a lot easier and cheaper to drawn the alloy into wire and then coat it with flux..

again, making durable electrical joints is not a simple matter of heating up a blob of alloy until it hits liquidus and then letting it cool. heck, look at the many many large package BGA failures we saw at the beginning of the RoHS era. xbox rrod anyone? a lot of engineering goes into designing drawn soldering wire to make hand soldering a reliable process. the same thing is true of reflow ovens or wave assembly lines and their respective alloy and flux packaging.

anyway, imo anything other than the direct physics of these processes are a debate beyond the scope of this thread.

i still assert that in simple DIP soldering with a commodity iron and the most common RA cored leaded wire and mildly or low activation flux cored lead-free alloys, the safe rule of thumb is: 1) use flux and debridement to lower thermal resistance. 2) form a strong mechanical connection between the joint materials (ie, twist wire together and secure workpiece. 4) clean and tin iron tip. 4) place tip against all joint components and soldering wire against joint components such that solder is not directly touching iron.

at this point, one of two things will happen. either the solder will melt and flow (hence the name flux for the oxide cleaning chemical!) into the joint, OR the solder will not melt. if it does not melt nearly instantaneously then you're either attempting to weld a car door closed (too much thermal mass) or you have too much thermal resistance at the joint. assume the latter case and repeat from step 1. eventually, you will get a feel for when the former case is true.

finally, after you have flowed solder into your joint, remove your solder wire and iron from the workpiece and DO NOT LET IT MOVE. the result should be a spherical, shiny joint (note that lead-free solders tend to form an oxide skin more quickly and hence will look a tad duller). if the joint is not spherical and/or shiny, wait for joint to cool a bit and then apply a drop of flux and heat until molten and let cool again.

the reason you want a spherical and shiny joint is that these are indicators for the joint being nominally defect-free internally. an aspherical joint implies that the cooling of the joint was not radially isometric through the centroid. when molten metal cools optimally, the phase change from liquid to solid happens at a uniform rate along the L1 norm from the centroid of the liquid mass.

a fun way to think about what is happening is to recall the form of the earth (which is also cooling!). at the center of the earth, the planet is composed of molten sphere (ok, not a perfect sphere, but close enough for now). we then consider concentric rings around the center to be in increasingly cooler, more solid forms such that each successive ring is cooler and contains more solids, until we reach the skin of the earth, that is dirt and oxygen. this is the pattern of a good joint cooling and eventually reaching a solid bulk.

to extend this metaphor to picture a bad joint, let's imagine that someone shook the earth like a snow globe as it initially cooled. instead of having concentric rings, we might have internal crags form where hot, low solid material flowed through cold, high solid material during the cooling process. in such a situation, the cool, solid material will have a different density than the hot material that runs past this. this point of density variance, taken to its limit, is basically a crack in the cooled bulk.

regardless of whether you flow mechanical or electrical energy through a bulk material, cracks are bad. under mechanical stress, they break. under electrical stress, they force electron holes to take irregular paths through the material, which will increase resistance and, under a large number of cycles, increase resistance enough to effectively break the electrical connection.

[mkawa]

also, the horrific pricing of 230v soldering irons around the world is definitely on-topic in this thread. it's shockingly hard to get a soldering iron that takes wall voltage from most of the world. it's quite bizarre and worth talking about, as we have a large number of international members here.

[heedpantsnow]

Good gosh mkawa

[twiddle]

I wonder if it is worth doing an IC for a GB for a good quality 230V iron with maybe hot air capability?
I'd tentatively volunteer, but might not be in a 230V country in the near future if certain game developers get their act together with regards to staffing.

[Parak]

Well... while I still can't claim to be an expert on soldering by any means - I'm just a wannabe and it's not as if I'm IPC certified or something - I can still at least point to some other sources of information on the matter in regards to temperature requirements for hand soldering lead-free:

Here's what Pace (primary supplier of soldering equipment to the US government/NASA/Navy, inventors of desoldering stations, etc) has to say about it:

Because lead-free solders have higher melting temperatures than solders containing lead, there is an immediate tendency to turn up the temperature on the soldering system. Higher operating temperatures do not make the process quicker and introduce  unnecessary risk factors. Leaded solder typically melts at 363F and lead-free solders melt in the neighborhood of 425F, an iron set at 650 or 700F will still melt lead-free solder. The issue isn't temperature; it's the ability of your iron/tip configuration to transfer heat to the work efficiently and the heater's ability to keep up with the heat loss into the work. High performance tips are available from several manufacturers and an evaluation should be undertaken to thoroughly understand how efficiently heat is being transferred from your existing tips to the work.
...
To maximize the life of your soldering tips:
1. Always use the lowest effective temperatures while soldering

Metcal, indicating actual temperature used in lead-free hand soldering as 300c:

If excessive process temperatures, and subsequent thermal damage to assemblies, are to be avoided in the lead-free hand soldering process the following aspects must be considered:
...
3. Thermal performance of the soldering iron. The ability of the soldering iron to input the correct rate of temperature rise to the solder joint is important, both with respect to flux activation and also final solder joint temperature.
4. Tip Temperature. Existing tip temperatures can be used in most applications providing the correct tip shape is implemented as well as good housekeeping techniques. Higher tip temperatures may be needed for very thermally demanding applications.

JBC specifically goes into some of the points that I'm trying to make:

Which is the suggested soldering temperature in lead free processes?
Our experience shows that 90% of solder joints using JBC tools can be performed successfully at 350C or less, in any case it is not recommended to exceed 370C.

Why is it possible to solder at lower using a JBC tool?
It is possible because the tip has an extremely fast thermal response.
On a conventional iron’s tip there is a strong drop in temperature while the tip is transferring the heat to the board. If the thermal response is slow, the tip does not have the time to recover the temperature, especially if a series of solder joint is performed. This is the reason why the operator is used to select a higher temperature, resulting in short tip life and PCB / component damage.

Hakko:

Simply raising the temperature of a soldering iron because of the high melting point may result in faster oxidation and erosion. The problems with lead-free solder can be solved by using products which offer special characteristics described below.
1. Soldering iron
Accurate temperature control and excellent thermal recovery rate enable the use of lead-free solder without the need for setting a higher temperature.

All the linked documents, even outside of the specific quotes, make for interesting light reading for anyone doing soldering.

One can argue that the reason why they all have a consensus is because they have well behaved stations in regards to thermal load demands, and they want to show it off.. but I'd rather not use irons that are not capable of this on lead-free. The rate at which one will tear through cheapo tips at 450c and the chances of ruining the boards and components makes the added expense of a proper station and tips suddenly much more attractive.

[mkawa]

yah, that's all marketing-speak. it's unsurprising that iron manufacturers will go on and on about their precision and thermal response. the two things they really care about are tip costs vs average usage rates and heater lifetime. those are the things that actually make them money.

to tldr the above, you must activate all of the flux in a solder to make a clean joint, and nearly all parts have wide and long thermal envelopes, since parts manufacturers lose money if their parts consistently die when soldered. finally, the absolute accuracy of your iron temperature is going to drift significantly over time, so trying to nail the exact melt temp of the soldering alloy is kind of an exercise in futility even if it were a good idea to hand solder at that temperature. set your temperature high enough to process your flux and make shiny joints and divert any excess brain to focus on making more and cooler stuff.

[Parak]

Okay. So if we assume that it's marketing speak, or even if it doesn't matter, there are still two possible scenarios:

1. What they claim is true.
2. What they claim is false.

Although I believe the former, let's suppose for a second that the latter is true. That means that every single large industrial customer of said companies, that might have thousands of their stations and following their guidelines, is going to be soldering at an incorrect temperature, leading to many failures and so on. Eventually, the problem will be traced back to the manufacturer of the soldering stations, leading to widespread lawsuits/recalls/etc. Odd that we haven't heard of those, however.

But let's set that aside for a moment and look at some non-affiliated examples, out of interest:

IPC, who develops the vast majority of the standards used in the industry, as well as certifications has the following to say on the matter in one of their training courses:

As stated previously, the melting temperatures are up to 40 degrees C higher. For example, a soldering iron temperature for a lead-free process may be 400 degrees C versus 360 degrees C for tin-lead.
...
Now, let’s take a look at the soldering operation. For this example we’ll use a tin-silver-copper alloy that has a melting temperature of 217 degrees C. We’ll be using a temperature- controlled
soldering iron with a chisel tip. The temperature will be set at 410 degrees C

Higher than the soldering equipment manufacturers ask for, but we don't know which irons are used for this particular training (AFAIK, they used older model Pace stations that weren't as good, however). Still, not 450C.

Kester, on lead-free hand soldering. Error and typo prone, but I figured I'd link it anyway:

What is the best soldering tip temperature for lead-free SAC and SnCu?
The temperature of the tip or contact temperature is very important to ease the lead-free hand-soldering operation. When using 63/37 solders temperatures as low as 650ºF have been used but with lead-free 700-800ºF is best. The higher temperature does compensate for the slower wetting exhibited with these lead-free alloys. Above 800ºF issues of board and component damage may arise; at lower temperatures cold solder joints and flagging are the normal complaints.
...
ƒInsure the tips are designed for lead-free
Insure the temperature is set to 700-800 ºF

So, about 370C - 425C. Still not 450, and specifically warns against it. No indication of what iron was used.

Eptac, another IPC and JEDEC certification trainer:

There are two factors involved in making this selection, one being the mass of the metal being joined and second the size of the soldering iron tip.
As for the alloy being used, the 63/37 is liquidus at 183C and the new RoHS alloys, such as SAC305 and Sn100C have a liquidus temperature around 215C. With the soldering iron set at between 371C [700F] and 398C [750F], one should be able to solder most joints. If the mass of the joints is very small then the temperature of the solder iron could be reduced to 343C [650F].
It is recommended to use the lowest possible temperature which will reflow the total joint, as using higher temperatures will create more damage to the tip of the soldering iron which will increase tooling cost.
These temperatures are satisfactory for all alloys, be it either the standard Sn/Pb or the new Lead-free alloys such as SAC 305 and Sn100C.

No specific soldering iron being referenced.

IPC again, this time a newer and updated course:

For leadfree alloys, a good starting point is 350 degrees C, or 662 degrees F. Variations in the alloy, either tin-lead, or lead-free, will require variations to the starting point temperatures.
...
After we’ve prepared the tip of the soldering iron, we should be ready to start the soldering operation. We'll be using a temperature controlled soldering iron with a chisel tip. The temperature of the tip will be set at 315 degrees C, or 600 degrees F for tin-lead solder – and about 350 degrees C, or 662 degrees F for lead free solder.
...
Now, we’ll demonstrate the same soldering technique using lead free solder. The main difference is that lead free has a higher melting temperature than tin-lead – so instead of a starting temperature of 315 degrees C, we’ll set the temperature at 350 degrees C.

The course is listed as being demonstrated by a person from Pace, so one assumes that a more up to date Pace station is used.

ACI, a company specializing in IPC training, in particular for the DOD (Navy and Army):

Lead-free solder alloys generally have higher melting points. Therefore, the solder tip must be set to a higher temperature. For example, when using the lead-free solder alloy, tin silver copper (SAC-305), it was determined that the solder tip had to be set to 343°C / 650°F, as opposed to 315°C / 600°F for tin-lead (SnPb).

Solder iron shown in the picture appears to be a Metcal.

A Linkedin discussion of the topic, between people involved in the industry, quote is from a certification instructor:

When I teach J-STD-001 or IPC-7711-7721, I start the students at 600°F for Sn/Pb and 650°F for SAC305 when learning on the standard IPC circuit board. However, our company work instructions are sometimes customized for the factors mentioned above. I find that component and PCB damage usually occurs when the operator compensates for the factors (poor soldering) by turning the temperature up where the control base allow (my favorite bases are from OKi / Metcal that doesn't allow operator manipulation) or by using a tip that is too large (actual temperature can deviate +25-50°F higher than indicated on the base, when measured with pyrometer). In this area, Gerald's advice is vital - quality of the tools matter.

That's ~350C. Metcal is referenced.

So, there seems to be at least some pattern of where a quality iron is used, the temperature reduction for lead-free hand soldering is achieved, lending credence to manufacturer claims. Even when the iron is unknown, nobody used 450C and specifically warned against it. All sources are what I'd personally consider authoritative on the subject matter, having significant impact in the industry.

All I'm trying to do is to prevent people from damaging their tips, equipment and components trying this at 450C with cheap stations. I'm not sure what other proof I need, other than perhaps demonstrating lead-free soldering myself at mentioned lower temperatures. I do have stations from Pace/JBC/Metcal as well as cheaper Hakko heater type stations for comparison at same temps, though I am lacking in lead-free solder - but that's easy to fix.

[Melvang]

I know this is a bit off the beaten path here, but I have a soldering question.  I want to cut the tabs off my AT that hold the stock controller on and move them to the middle of the plate so that the entire controller is hidden from view.  It is being used without a case.  Plus with the xwhatsit controller, only one of the tabs gets used and I want to use both for a better connection to ground plane of the back plate.  Would silver based solder from a home improvement store from the plumbing section be sufficient?  Or should I purchase a better quality solder from the web?  What sort of silver content should I be looking for?  This is going to be soldering steel to steel, and am planning on using a propane torch. 

The reason I am wanting to solder is because I feel I will be imposing less warpage to the back plate than if I was to attempt to TIG weld it.  Plus, I don't want to use standard leaded solder as it doesn't have the same mechanical strength that silver based solder does.

[Bucake]

can't find the edsyn 915sx-230 anywhere closeby :/
ordering from edsyn.com would give me: 951sx-230 for $266, then $130 shipping cost. import charges would be around $115.
which would total out at more than $500. just nasty..

what are my options? anyone know of a european seller of these?
or otherwise a good alternative to this station..?

[mkawa]

yes, edsyn does have a european distributor. PM me and i'll get back to you with details.

[mkawa]

I know this is a bit off the beaten path here, but I have a soldering question.  I want to cut the tabs off my AT that hold the stock controller on and move them to the middle of the plate so that the entire controller is hidden from view.  It is being used without a case.  Plus with the xwhatsit controller, only one of the tabs gets used and I want to use both for a better connection to ground plane of the back plate.  Would silver based solder from a home improvement store from the plumbing section be sufficient?  Or should I purchase a better quality solder from the web?  What sort of silver content should I be looking for?  This is going to be soldering steel to steel, and am planning on using a propane torch. 

The reason I am wanting to solder is because I feel I will be imposing less warpage to the back plate than if I was to attempt to TIG weld it.  Plus, I don't want to use standard leaded solder as it doesn't have the same mechanical strength that silver based solder does.

i'd just JB weld it.

[mkawa]

assembly processes are dependent upon the composition of your assembly, your process tooling and all chemicals involved. in particular, you _must_ activate the flux in your solder. inactive flux inside of solder balls will eventually lead to failure of the joint. for kester 44 RA active rosin flux, the recommended processing temperature is appx 350C

for kester 285, a 5% silver alloy with mildly active water soluble flux, the recommended processing temperature is appx 400C

http://www.kester.com/download/44%20Flux-Cored%20Wire%20Data%20Sheet.pdf

if your components cannot handle exposure to contact heat at that temperature, you will want to use a different solder. because the focus of this thread is to inform new and intermediate assemblers, i recommend 350C as a good temperature for kester 44 RA, and 450C for water-soluble lead-free solders. in contrast, most solder pastes will recommend temperatures about 100C lower as the flux does not need to be nearly as active due to the even distribution of flux within the paste.

regardless, this discussion is best left to an advanced soldering thread. like this one! https://geekhack.org/index.php?topic=70128

[Melvang]

I know this is a bit off the beaten path here, but I have a soldering question.  I want to cut the tabs off my AT that hold the stock controller on and move them to the middle of the plate so that the entire controller is hidden from view.  It is being used without a case.  Plus with the xwhatsit controller, only one of the tabs gets used and I want to use both for a better connection to ground plane of the back plate.  Would silver based solder from a home improvement store from the plumbing section be sufficient?  Or should I purchase a better quality solder from the web?  What sort of silver content should I be looking for?  This is going to be soldering steel to steel, and am planning on using a propane torch. 

The reason I am wanting to solder is because I feel I will be imposing less warpage to the back plate than if I was to attempt to TIG weld it.  Plus, I don't want to use standard leaded solder as it doesn't have the same mechanical strength that silver based solder does.

i'd just JB weld it.

The problem with JB weld is no electrical connection for the ground plane.

[Parak]

if your components cannot handle exposure to contact heat at that temperature, you will want to use a different solder. because the focus of this thread is to inform new and intermediate assemblers, i recommend 350C as a good temperature for kester 44 RA, and 450C for water-soluble lead-free solders. in contrast, most solder pastes will recommend temperatures about 100C lower as the flux does not need to be nearly as active due to the even distribution of flux within the paste.

regardless, this discussion is best left to an advanced soldering thread. like this one! https://geekhack.org/index.php?topic=70128

I'll be happy to take discussion of things like professional grade soldering stations and reflow/rework to the other thread. However, your recommendation for said new and intermediate assemblers is still in this thread to hand solder and desolder lead-free at 450c is, again, not supported by anything that I've read so far, and in fact is only actively discouraged. All of my sources are specifically concerning hand soldering lead-free, and not paste/reflow soldering, and in fact for paste reflow the recommended temperatures are  about 200c lower - but again, that's irrelevant and for the other thread.

I would have liked to find some well supported and documented industry use cases for hand soldering lead-free at 450C as a generic guideline, but I have not been able to locate anything outside of this thread. As such, I'd prefer for the aforementioned new and intermediate assemblers to avoid damaging their equipment and components unnecessarily by using such a high temperature.

[mkawa]

it's still a valid recommendation even if it is because entry level stations don't have the power delivery mechanisms needed to maintain a lower process temp.

[Parak]

I suppose one should then define what an entry level iron is, which is capable of 450C temperature adjustment. Considering that one can get a Hakko 888 for $70 at frys quite frequently, I would not go any lower than that. The 888, according to the reports I've read, is perfectly capable of processing lead-free at 400C. Even a Weller WES(D)51, which is only 50 watts, was reported by a friend of mine to be used throughout their company as a soldering station for lead-free at 400C.

If anything, I'd outright advise against even trying to do lead-free soldering with cheaper stations that can't meet the thermal or tip quality requirements, like the various Chinese Hakko 936/937 clones for example. And as far as desoldering goes... well, one could use a cheap station for that at 450C only if they are willing to accept the much higher risks of irreversible damage to all the parts involved.

[Melvang]

I use my Weller WES51 to desolder lead free on occasion.  I just turn it up a little over 3/4, since it is just an arbitrary 1-5 setting, add leaded solder to each joint.  Then I turn it down and desolder with a soldapult.

[bpiphany]

I've been a bit skeptic to the very high temperatures suggested by mkawa. Why go much higher than necessary for the solder to melt, I wondered. But just to try I set my station to 450 rather than the 380 I normally use. I may just be imagining but I think my tip actually kept cleaner from crusty flux crap and cleaned up nicer against the sponge. I worried a bit and lowered the temperature to 400, and I think it's still better than 380. I will keep looking for my optimal temperature, probably higher than 380.

I think the most interesting figure should be what the manufacturer of the lead says is the correct temperature. They if anyone should know how they designed their alloy/flux to work..

[jdcarpe]

I've been a bit skeptic to the very high temperatures suggested by mkawa. Why go much higher than necessary for the solder to melt, I wondered. But just to try I set my station to 450 rather than the 380 I normally use. I may just be imagining but I think my tip actually kept cleaner from crusty flux crap and cleaned up nicer against the sponge. I worried a bit and lowered the temperature to 400, and I think it's still better than 380. I will keep looking for my optimal temperature, probably higher than 380.

I think the most interesting figure should be what the manufacturer of the lead says is the correct temperature. They if anyone should know how they designed their alloy/flux to work..

My Hakko FM-202 stays on 750F (400C) all the time. I tried 650F and 700F, but 750F melts the solder quickly, more reliably in the case of lead-free, and seems to me to be "cleaner" as well.

[Parak]

I've been a bit skeptic to the very high temperatures suggested by mkawa. Why go much higher than necessary for the solder to melt, I wondered. But just to try I set my station to 450 rather than the 380 I normally use. I may just be imagining but I think my tip actually kept cleaner from crusty flux crap and cleaned up nicer against the sponge. I worried a bit and lowered the temperature to 400, and I think it's still better than 380. I will keep looking for my optimal temperature, probably higher than 380.

I think the most interesting figure should be what the manufacturer of the lead says is the correct temperature. They if anyone should know how they designed their alloy/flux to work..

You can check some of my links on the previous page - I provided one of them from Kester. However, it varies drastically depending on the quality of the soldering station and the tips, and it's simple physics at how higher temps cause a decrease in tip life. Kester also specifically mentions how higher temperatures directly lead to joint embrittlement in lead-free due to increased thickness of the intermetallic bond layer.

[twiddle]

I've been hunting around for a while now for a good quality 220-240V hot air station.
I've been given a quote for one of these Goot stations , direct from the manufacturer, about $850 AUD shipped (exact quote was 74800 yen + paypal fees) including the vacuum attachment and a few extra nozzles.
The price is a bit higher than I really wanted to pay, but I don't mind as much if it is well-manufactured (country of origin states Japan, but it's been suggested to me that pehaps the internals are actually all Chinese with just the assembly/testing conducted in Japan, hence my uncertainty as to whether it's worth the money).

I don't really want to get a cheap-nasty/clone unit, I've been spoilt with the hand iron I've used to date (goot PX-601), not to mention it wouldn't be the first time I've seen an Aoyue or similar station have the wiring in an unsafe manner.
There are only a handful of Australian sellers with good-quality equipment, and it all seems to be in the $800+ range without vacuum attachment or extra nozzles (the vast majority of Australian stock seems to be more like $1200+ which is insanely ridiculous for my present needs).

I was pointed towards JBC (european made, hence native 230V), and the Korean/Singaporean second-hand market, as a place to start looking.
Any other suggestions from GHers regarding alternatives? Any native speakers mind taking a look and letting me know if there's much on offer?

[mkawa]

I think the most interesting figure should be what the manufacturer of the lead says is the correct temperature. They if anyone should know how they designed their alloy/flux to work..

as with most things in manufacturing, every finished part is a complex series of choices that carefully balance engineering goals against each other. designing and/or specifying a soldering material is as much if not more important than constraining the process of using that material.

in an earlier post i alluded to the choice of where and how to distribute the flux in a soldering material. flux is corrosive, and hence inherently unstable. flux is drawn into the core of soldering wire because the drawn metal around the flux can keep it from reacting before it is needed in the creation of a soldering joint. solder paste, on the other hand, is designed so that flux is near-uniformly distributed within the alloy. the tradeoff is that the flux is exposed in pastes and hence solder paste is not 'shelf-stable' and will become inert if not refrigerated and used quickly. this is also why you can approximate solder paste by mushing up soldering wire in a bit of flux paste with a mortar and pestle.

finally, while we think of temperature as an exact property of matter, this is a reductive notion meant to keep our heads from exploding. i wrote up a few pages on this, but it turned into a thermodynamic mess (as most thermodynamics are..), so i'll just say that we can turn our little temperature controller knobs to demarcated points on their travel until our heads do explode and we won't ever be able to say that we've hit exactly X temperature.

hell, i have a thermocouple amplifier chip (singular) that cost more than my first soldering iron.

in short, turn your knob until your get good results with your solder and joints and be happy, folks!

[Parak]

I've been hunting around for a while now for a good quality 220-240V hot air station.
<snip>

I posted my reply over here, as that's a better place for it.

[alexofthewest]

What temperature should I use on my hakko 880d for soldering some switches and desoldering? This will be my first attempt

[Joey Quinn]

What temperature should I use on my hakko 880d for soldering some switches and desoldering? This will be my first attempt

350 Celsius, also for desoldering you may want to buy some flux, it'll speed up the process. 

[heedpantsnow]

What temperature should I use on my hakko 880d for soldering some switches and desoldering? This will be my first attempt

Crazy, I asked the same question a few pages back and got a lot of valuable info. You may want to go check that out.

[Melvang]

Since my iron doesn't have a temp readout, just an arbitrary 1-5 number scale, I just set it at the lowest setting that it quickly melts the solder needed for the joint.  With lead free, I do tend to turn it up a bit.

[mkawa]

stations with arbitrarily demarcated knobs (in particular the weller wlc100) are fixed temperature soldering irons that are connected to a varistor that controls the voltage into the iron. that is, the iron heats up until its heater hits equilibrium, usually about 400-450C at appx 50W max at wall voltage (wcl100: 40W max). turning the knob does not change the max temperature of the iron. instead, turning the knob changes the wattage of the iron. the lowest setting is usually about 15-20W, with fairly linear steps up to the maximum. with these stations, just find a setting that works for you and leave it there. increasing the wattage of the iron really is a patch to make up for slow thermal recovery.

[azhdar]

One of the switch wasn't working (pressing it or doing a contact onto the solder points, so I desoldered it and I still can't see what's wrong:

Show Image

Show Image

Note: the 2 points were working before I tested the pcb when received, not working anymore sadly.
Can you guys help me?

The diode what RSIII uses is 1n4148 in 0805 package

This : http://www.amazon.fr/1N4148-IN4148-SOD-323-Switching-Diode/dp/B00CN530MA/ref=sr_1_1?s=electronics&ie=UTF8&qid=1426064622&sr=1-1&keywords=1n4148+0805#productDetails
should work right?

Received the diodes so follow up questions:
- how do I tel the polarity one those things (amazon link above), they don't seem to have any distinction on them ?
- do you have any trick to solder this thing? I have only one diode to solder but I'm with a 10$ iron. I though of doing a "pool" of solder onto the pad and then putting the diode in it.

[jamster]

Why do people keep talking about lead free solder? Is there some kind of advantage to it, or is leaded solder hard to get in the US/EU?

[Melvang]

Why do people keep talking about lead free solder? Is there some kind of advantage to it, or is leaded solder hard to get in the US/EU?

Because it is used for all manufactured boards due to having to comply with RoHS regulations.  You can still buy leaded solder which is usually easier to work with for the hobbyist.

[Parak]

Received the diodes so follow up questions:
- how do I tel the polarity one those things (amazon link above), they don't seem to have any distinction on them ?
- do you have any trick to solder this thing? I have only one diode to solder but I'm with a 10$ iron. I though of doing a "pool" of solder onto the pad and then putting the diode in it.

Diodes without polarity is unfortunate - look carefully maybe there's a dot instead of a line or something at least. If not, it's hard to check unless you have a multimeter, so I'd just return them as they'd be some really low quality ones anyway. Also, they're a bit of a wrong size, sod 323 is not exactly size compatible with 0805 - but you should have at least some overlap between the two, assuming you can find polarity.

To solder, make sure you have a thin pointy tip that is bright and shiny without excess solder. Take some thin gauge solder, and melt a tiny bit on the pad, just enough to cover it. If there's already solder on the pad, you can skip that. Take the component, place it in the correct orientation, and slightly solder one leg of it to the pad. Take a bit more solder, and solder the other pad, then add a bit more back to the first pad so that it forms a clean joint. Less solder is more for smd - be careful not to use too much, as these are small components with small leads and pads. Never keep your iron on a pad and component for longer than a few seconds, either.

[azhdar]

Received the diodes so follow up questions:
- how do I tel the polarity one those things (amazon link above), they don't seem to have any distinction on them ?
- do you have any trick to solder this thing? I have only one diode to solder but I'm with a 10$ iron. I though of doing a "pool" of solder onto the pad and then putting the diode in it.

Diodes without polarity is unfortunate - look carefully maybe there's a dot instead of a line or something at least. If not, it's hard to check unless you have a multimeter, so I'd just return them as they'd be some really low quality ones anyway. Also, they're a bit of a wrong size, sod 323 is not exactly size compatible with 0805 - but you should have at least some overlap between the two, assuming you can find polarity.

To solder, make sure you have a thin pointy tip that is bright and shiny without excess solder. Take some thin gauge solder, and melt a tiny bit on the pad, just enough to cover it. If there's already solder on the pad, you can skip that. Take the component, place it in the correct orientation, and slightly solder one leg of it to the pad. Take a bit more solder, and solder the other pad, then add a bit more back to the first pad so that it forms a clean joint. Less solder is more for smd - be careful not to use too much, as these are small components with small leads and pads. Never keep your iron on a pad and component for longer than a few seconds, either.

gotcha thanks!