Metcal soldering irons way too hot? - Page 1
Forum section: electronics / general

author: macboy
author_rank: Super Contributor
timestamp: May 31, 2016, 06:18:36 pm
content: I recently bought a 2nd-hand Metcal soldering iron (13.56 MHz tech) along with a bunch of new-old-stock tips. A few of the tips were 600 series (STTC-0xx) and most were 700 series (STTC-1xx). I found that the 700 series tips are too hot, and not just a little, but justwaytoo hot. I had read that these Metcal stations are the bee's knees because they deliver tons ofheatwithout being toohot. In other words, they don't need a high tip temperature to be able to deliver lots of heat quickly, as the heater technology (curie point RF heating) responds instantly to tip temperature reductions and delivers tons of heat without ever overshooting the temp. What I observe is nothing like that. Yes, it delivers lots of heat, but it's because the tip is scorching hot.The problem is that the 700 series tips operate at 775oF, which is absurdly high isn't it? I was able to very easily lift pads (non plated hole) off of FR4 boards just by dwelling on them for several seconds (5 to 10 seconds). The pad just lifted off the board with the surface tension of the solder (no other mechanical force). Yes, this is much longer than necessary for making a solder joint, but that's not the point. The tip is too hot, and can't be adjusted.Damage to pads is not the only issue. The high temperature of the 700 series tips burns flux, resulting in much more fumes than I'm accustomed to, and the resulting dark brown residue is also much harder to remove. The same rosin core solder leaves a hard water-clear residue that is very easy to clean with IPA, when soldering with my other iron (Weller FE-75) set to 625oF.The 600 series tips seem much more reasonable, operating at 675oF max. But Metcal says "700 Series for most standard applications." and "600 series ... for temperature sensitive applications". Is 775 degrees "standard" by anyone's standards?I want to know what other people think of Metcal technology, what series of tips do you use, and what kind of solder (lead/lead-free).

author: PChi
author_rank: Frequent Contributor
timestamp: May 31, 2016, 06:36:36 pm
content: I use the 700 series at home with JBC at work. I can believe that if the Metcal is held too long it can lift pads. It just depends what you are used to.The ability to get heat to the tip is useful when trying to solder surface mount, especially to ground planes.I failed on one part with the JBC iron turned up to 400 C with leaded solder.If the iron is for through hole parts then the old Weller TCP irons work well. I just modify the technique to suit the iron.

author: Monkeh
author_rank: Super Contributor
timestamp: May 31, 2016, 06:46:02 pm
content: So buy the 600 series tips?The 700s are fine for leaded and lead-free work so long as you perform as well as the iron. If you try and use too cool a tip, you'll lose even more pads in difficult situations.'temperature sensitive applications' include non-plated through holes, which are hilariously flimsy at the best of times.

author: mmagin
author_rank: Frequent Contributor
timestamp: May 31, 2016, 08:00:50 pm
content: For leaded solder work, I almost exclusively use 500 and 600 series tips. I only have a big 700 series chisel tip for when I want to hear big things.

author: D3f1ant
author_rank: Frequent Contributor
timestamp: May 31, 2016, 08:38:01 pm
content: 600 is fine for almost everything. 500 for sensitive Pb only and 700 series for NoPb. The 'clear' fluxes in Pb solder go fairly brown with 700. It pays to buildup a collection of tips, everybody seems to have a different favourites.

author: GreyWoolfe
author_rank: Unknown
timestamp: May 31, 2016, 10:32:39 pm
content: __The problem is that the 700 series tips operate at 775oF, which is absurdly high isn't it? I was able to very easily lift pads (non plated hole) off of FR4 boards just by dwelling on them for several seconds (5 to 10 seconds). The pad just lifted off the board with the surface tension of the solder (no other mechanical force). Yes, this is much longer than necessary for making a solder joint, but that's not the point. The tip is too hot, and can't be adjusted. __According to a Metcal doc I found, each series of tips will go to X75 degrees--700 series max temp is 775 degrees. Perfectly normal. I use 600 series myself without issue. I chose them because I keep my Hakko FX-951 at 650F. By the way, I get dark brown residue with the 600 tips, I use fume extraction and I clean my work off with IPA and a tooth brush when done.Any soldering iron will lift pads if held in place long enough. I was taught the 3 second rule. If the solder doesn't flow in 3 seconds, I remove the iron, pause a bit for the pad to cool and apply heat again. That was an issue with my Hakko 936 and isn't a problem with my FX-951 and MX-500. I think 5-10 seconds is too long, especially 10 seconds-ouch!Their definition for 'standard applications' may be for a production or repair/rework environment where speed counts and not necessarily for hobbyist use.

author: nanofrog
author_rank: Super Contributor
timestamp: June 01, 2016, 04:15:30 am
content: Quote from: macboy on May 31, 2016, 06:18:36 pmFor lead based solder, I'd also recommend going with the 600 series (generally speaking, 600 - 700F works very well for lead based solder). The 700 series would be more appropriate for lead-free solder (800 for large lugs and connectors for example).Quote from: macboy on May 31, 2016, 06:18:36 pmThe tech they use generated much better performance at the time it was introduced, but other manufacturers have since caught up using non-RF based tech. And in some cases, even exceeded it. Induction based Curie Point stations are still great performers, but the comments they kick everything else to the curb aren't universally valid any longer IME.For example,GreyWoolfe's Hakko FX-951 performs at least as well as his Metcal MX-500 based on his comments during our back and forth via PM's. Common profile tips are cheaper too (Metcal v. Hakko; Thermaltronics v. Hakko are similar in price).FWIW, here's a couple of threads that might be of interest.Hakko FX-951 ReviewHakko FX-951 or Thermaltronics TM-2000--Looking for opinions

author: RobertHolcombe
author_rank: Frequent Contributor
timestamp: June 01, 2016, 04:34:16 am
content: Quote from: GreyWoolfe on May 31, 2016, 10:32:39 pmAgreed.Particularly for non plated through-hole boards, there's barely any thermal mass so pads will very easily be removed.Dwell time should be as low as possible regardless of the joint, if over 5 seconds then the thermal mass of the iron is insufficient or there is insufficient thermal coupling between the iron and joint - either because the tip or joint is heavily oxidized and requires cleaning, or because insufficient solder is being applied, or the shape of the tip is unsuitable.

author: Psi
author_rank: Super Contributor
timestamp: June 01, 2016, 09:22:46 am
content: I have a 700 series on my thermaltronics (350°C - 398°C)http://www.thermaltronics.com/datasheet/M7CH176It doesn't seem "crazy hot" at all, just "perfectly" hot.Might be different to Metcal though.

author: wkb
author_rank: Super Contributor
timestamp: June 01, 2016, 12:10:28 pm
content: Example of a good craftsman does not blame his tools.. know your tools and use them properly. Metcal is an excellent soldering system assuming you know about which 'heat grade' tips to use.

author: Monkeh
author_rank: Super Contributor
timestamp: June 01, 2016, 01:01:38 pm
content: Quote from: nanofrog on June 01, 2016, 04:15:30 amThey are, however, still among the best performers, have a very wide range of tips, and are simply put, an elegant solution.Also, they're not blue and yellow.

author: nanofrog
author_rank: Super Contributor
timestamp: June 01, 2016, 02:25:51 pm
content: Quote from: Monkeh on June 01, 2016, 01:01:38 pmI absolutely agree on the color scheme.As per the RF Curie Point based stations, they're certainly still good performers (wasn't my intent to imply otherwise).The fact the operator cannot screw with the temps makes them an excellent production station (process control remains intact).For a bench that could potentially see anything come it's way however, I find a temp adjustable station is more appropriate. It's also more cost effective IME, as there's no need to duplicate tip profiles in order to get different temperatures (assumes good quality tips that last).YMMV of course, and there's also ergonomics to consider as a general rule as well. I'm quite partial to pencil shapes vs. the broom handled sized stuff that was available in the not too distant past for example (some still is).Tip selection is an excellent point as well, as some are rather limited (i.e. when a new station/iron is first released). Once they've been around for awhile however, the manufacturer *usually* offers a decent selection as they've had time to respond to customer requests and adapt to new component packages if/when that occurs.

author: macboy
author_rank: Super Contributor
timestamp: June 02, 2016, 12:05:28 pm
content: Would you ever set your adjustable station to 775oF ?No.Then why is a Metcal tip running that hot?Their marketing says that:QuoteThatsoundsgreat. Everyone has at some time or another cranked up their soldering station way higher than normally necessary in order to handle a tough joint on a ground plane or big connector. And you hate doing it because you know you will make a lot of smoke, melt wire insulation, and might cook the board. So having an iron that can deliver lots of heat on demand without a excessive tip temperature sounds great. So why do they depend on an excessively high 775oF tip temperature? I haveneverneard of anyone using 775oF as their everyday set point for their conventional soldering station. They are doing the opposite of what they imply in the marketing.

author: GreyWoolfe
author_rank: Unknown
timestamp: June 02, 2016, 02:30:48 pm
content: As far as the color scheme of the Hakko, meh. I am far more interested in function over form. It could be purple with pink polka-dots, but if it does the job, that's what I am interested in. Besides there is nothing wrong with a little color to break up the whites, greys and blacks of all the stuff on the workbench.

author: nanofrog
author_rank: Super Contributor
timestamp: June 02, 2016, 06:35:48 pm
content: If the color scheme is that annoying or dull, you can always use some spray paint.For painted over markings/labels, make a stencil or just use a label printer.Then you can have your purple w/ pink polka-dot station/s.

author: Marco
author_rank: Super Contributor
timestamp: June 02, 2016, 07:18:35 pm
content: Some day I'd really like to see reviews with proper testing of the ability of irons to maintain temperature when hitting controlled thermal loads which approximate real world tasks.I suspect the modern "high frequency" irons will have the advantage.

author: continuo
author_rank: Frequent Contributor
timestamp: June 02, 2016, 08:34:34 pm
content: I don't know. The Metcal fanbois run their irons at insanely high temps and then keep bragging about how well it performs. Crank a JBC or Ersa up to Metcal temps (*) and I suspect it would perform every bit as good, if not better.(*) not that anyone in their right mind would do this...

author: amwales
author_rank: Regular Contributor
timestamp: June 02, 2016, 10:02:07 pm
content: The documentation for the Metcal mx500 (http://www.e-tronics.hu/v4/e69bc5c4-143b-4e1a-8b00-6e75fc4558c9/uploads/mx500_manual.pdf)600 series for most applications and 700 for heavy ground planes.I've only ever used 600 series tips, leaded solder and liquid flux, both through hole and smt and have never had the problem you describe.

author: macboy
author_rank: Super Contributor
timestamp: June 03, 2016, 12:55:34 pm
content: Quote from: amwales on June 02, 2016, 10:02:07 pmThis contradicts the attached documentation for the cartridges themselves, they list:"700 Series for most standard applications.", and"600 series and ... 500 series also available for temperature sensitive applications."

author: nanofrog
author_rank: Super Contributor
timestamp: June 03, 2016, 01:35:34 pm
content: Quote from: macboy on June 03, 2016, 12:55:34 pmI suspect when the manual was written, leaded based alloys were still the standard. Thus the 600 series were the recommended tips for most applications. Once RoHS kicked in however, that recommendation had to be shifted to the 700 series to work with the newer lead-free alloys. So the latest marketing materials & data sheets reflect that.

author: georges80
author_rank: Frequent Contributor
timestamp: June 05, 2016, 06:56:59 pm
content: I've used 1xx (700 series) tips for 10+ years with my mx500. Never had problems/issues with lifting SMT pads etc, but then I don't sit the tip of the iron on those pads for 5-10 seconds. A good solder joint takes < 1/2 second on SMT devices. If you have large components tabs (power devices) to solder, then maybe a second or two.My tips last a long time. I use no-clean 63/37 solder and have no 'brown' flux residue. IPA will clean things nicely when needed.I've used various makes/models of soldering irons in my rather lengthy career and they will have to drag my mx500 out of my dying hands...Learn to use the tool correctly and it'll be a great performer. If you don't like the 1xx temperature, then get 0xx.cheers,george.

author: SteveyG
author_rank: Unknown
timestamp: June 06, 2016, 08:09:30 am
content: Quote from: georges80 on June 05, 2016, 06:56:59 pmAlso (at least with the MX-5200 and accessories) no handpiece heating! The JBCs at work I find unusable after 15 minutes or so - they just get so hot on the finger grip.I tend to hold my soldering iron close to the end of the grip so probably notice this more than others but the Metcal stays cool after hours of use.I've used most other brands and never really adjust the temperature so I don't miss that functionality - 330°C at all times on those systems.

author: EEVblog
author_rank: Unknown
timestamp: June 06, 2016, 08:34:19 am
content: Quote from: wkb on June 01, 2016, 12:10:28 pmYes, but changing tips is inconvenient, and it's a big jump between tips.This is why I hate and avoid fixed temp soldering irons.

author: EEVblog
author_rank: Unknown
timestamp: June 06, 2016, 08:35:49 am
content: Quote from: SteveyG on June 06, 2016, 08:09:30 amMy JBC turns off when you return the iron to the holster, heating up again instantly each time you pick it up.

author: SteveyG
author_rank: Unknown
timestamp: June 06, 2016, 10:12:17 am
content: Quote from: EEVblog on June 06, 2016, 08:35:49 amI think you misinterpreted what I was saying (or not?) - After about 15 minutes of soldering up a PCB, the handpiece itself is really quite hot to the touch, especially close to the metal ring at the end of the handpiece. It seems that the heater is a lot further down the tip whereas if you take out a Metcal tip, you can actually hold it half way down with bare fingers after use!

author: RobertHolcombe
author_rank: Frequent Contributor
timestamp: June 06, 2016, 10:01:45 pm
content: I've not experienced that with my T245, I do use a very light grip though

author: Monkeh
author_rank: Super Contributor
timestamp: June 07, 2016, 04:24:55 pm
content: I figure I'll just drop this here:https://www.youtube.com/watch?v=vIT4ra6Mo0s#t=12m11s

author: macboy
author_rank: Super Contributor
timestamp: June 07, 2016, 05:19:19 pm
content: You are missing the point. Of course a person can make great joints with a Metcal iron using the right technique. That isn't the point.The point is that Metcal itself claims that their irons can and do deliver large amounts of heat to the joint without resorting to high tip temperatures which might damage boards and components. Then they go and roast the tip at 775 degrees. Sure, you can make a joint very quickly, but if you take a second or two too long then you can destroy the board or component, because the tip is extremely high temperature. Does nobody else see the irony in that?

author: Monkeh
author_rank: Super Contributor
timestamp: June 07, 2016, 05:28:26 pm
content: No, I believe you're missing the point.The problem is not that Metcal are 'roasting' their tips, but that you've become used to using a far lower temperature than the norm.E: And I've just measured brand new Thermaltronics tips at 725F (385C in useful figures), and a well-aged STTC-125 at 695F (368C). Perfectly acceptable for lead-free and leaded.

author: macboy
author_rank: Super Contributor
timestamp: June 07, 2016, 07:01:02 pm
content: Quote from: Monkeh on June 07, 2016, 05:28:26 pmI'm willing to consider that I am simply accustomed to a lower temperature.I normally use Kester 44 60/40 leaded solder. The 44 flux is RA and wets amazingly well, maybe too well, and so yes I probably soldered at a temperature toward the low end.I am finding that with lead free solder (AIM SAC305 with 209AXT flux) or with lead solder having a non-Rosin based no-clean flux (Kester 245), the higher temperatures are quite OK. I still think there is a lot of smoke but I suppose that is expected with lead-free. In fact I previously did not like the Kester 245 because I found it did not wet well at all, especially compared to the Kester 44. The elevated temperature of this iron seems to activate this flux much better and it wets quite well now. Go figure.My preferred rosin-cored Kester 44 and Kester 285 solders do not fare well with the temperature of the 1xx series tips. Same issue with RMA flux pens (Kester 186 I think). The rosin leaves a lot of black crud build-up on the tip and the flux residue becomes harder and more difficult to remove from the board as well. The synthetic fluxes are much more manageable. I guess that's why lead free solder has synthetic flux rather than rosin.I use a Weller WFE2P fume extractor with my other irons. Yesterday I experimented with adding a (home-made) fume extraction nozzle to the metcal handpiece. It worked well, and makes quite a difference. The lack of fume extraction had compounded the issue of added smoke/fumes from the high tip temperature. I have one 0xx (600 series) tip and a 5xx (500 series) one on the way. I hope to continue using my favorite Kester 44 solder with the lower temperature of those tips.BTW the lifted pads I referred to in my original post were from cheap proto boards like this:These are very inexpensive (25 cent) boards that are actual FR4 with plated through holes. The pads that lifted off so easily are the ones at the perimeter. These boards are nice for practicing, especially when you are using a new iron that works very differently from what you are used to.I haven't yet soldered any "real" boards with the Metcal because I am still getting to know it.