Hot tweezers - I need some advice - Page 1
Forum section: electronics / general

author: deanclaxton
author_rank: Regular Contributor
timestamp: June 23, 2016, 11:00:01 pm
content: Hi,I'm in need of a hot tweezer setup. I primarily use a JBC compact station, but I'd have to upgrade to a modular station to add hot tweezers to that ($$$$). I also have an old Hakko 936 station and was considering a set of the Hakkp 950 tweezers but I was told that they are more like tongs that tweezers.At this stage I'm looking to use them to remove SMD electrolytic caps from vintage computer motherboards, but no doubt they will be handy for many other jobs. At present I'm using the Hakko on one side of a cap, and the JBC on the other, but some parts are glued and I often need a third hand to remove the part from the PCB while heating.Any recommendations on an economical precision hot tweezer setup if such a beast exists, or does anyone have something that they would like to part with (sell to me)?Cheers,Dean

author: nctnico
author_rank: Super Contributor
timestamp: June 23, 2016, 11:08:11 pm
content: Recently I got Ersa's hot tweezers:https://www.eevblog.com/forum/reviews/ersa-chiptool-quick-review/msg954633/#msg954633

author: nanofrog
author_rank: Super Contributor
timestamp: June 23, 2016, 11:31:01 pm
content: A few questions:Where are you located?What's your budget?Would you consider used if available?BTW, if you go into your user profile and set your country, it's flag will be displayed beneath your userID. Would make the first question irrelevant, thus getting you answers faster.

author: deanclaxton
author_rank: Regular Contributor
timestamp: June 24, 2016, 12:11:45 am
content: Sorry - yes I must update my profile.I am located in Brisbane Australia, and yes I would consider used ones if available. Budget wise I was trying to keep the price down as much as I can - I'll have to work out how much I can justify spending once I've fully evaluated the the options - I guess a decent set will cost good money, but hopefully would also be more versatile.Are the Metcal precision tweezers any good? There is a local sale on one of their MFR-1140 stations, but that would cost me around AU$545 by the time I have purchased cartridges for it. I've never used Metcal before.Cheers,Dean

author: uncle_bob
author_rank: Unknown
timestamp: June 24, 2016, 12:46:37 am
content: Quote from: deanclaxton on June 24, 2016, 12:11:45 amHiThe Metcal stuff is great, but expensive. To change temperatures, you change tips. If you only deal with one kind of solder, not a big deal. If you have three or four solder types running around the costs multiply pretty fast. Price out the gizmo *with* at least two spare sets of tips before you decide what to do. You don't have to buy it all at once, just be aware of the costs.Bob

author: nanofrog
author_rank: Super Contributor
timestamp: June 24, 2016, 03:12:35 am
content: Quote from: deanclaxton on June 24, 2016, 12:11:45 amMetcal is nice stuff, but as mentioned, if you need to work with more than a single family (leaded or lead-free only), it gets expensive quick for tips.If you're willing to build a controller for say a JBC PA-120 however, you could save yourself quite a bit from what I can tell.Take a look atsparkybg's universal soldering iron controller(dual channel, so it can operate the PA-120 tweezers).

author: RobertHolcombe
author_rank: Frequent Contributor
timestamp: June 24, 2016, 03:12:50 am
content: Hey Dean,I'm in Brisbane tooI have a JBC CP-2E compact station which I am willing to sell, however I would be selling it without the handpiece/cartridges. I bought it from Mektronics on special and then upgraded to a DME control unit, so have no use for the compact station anymore.edit: It had around 5-6 weeks use, still has all the original packaging, manuals, cables etc, its been in the box since I stopped using itRegards

author: SteveyG
author_rank: Unknown
timestamp: June 24, 2016, 08:06:38 am
content: Just use a second soldering iron. Must more practical and universal.

author: nctnico
author_rank: Super Contributor
timestamp: June 24, 2016, 12:14:20 pm
content: Quote from: nanofrog on June 24, 2016, 03:12:35 amNot true. 330 deg. Celcius works excellent for both leaded and unleaded solder. The biggest problem I see with soldering is people using tips which are too small so they crank the temperature up (which causes heaps of other problems).

author: uncle_bob
author_rank: Unknown
timestamp: June 24, 2016, 12:56:41 pm
content: Quote from: nctnico on June 24, 2016, 12:14:20 pmHiIf you can get away with only one temperature tip, you are very much in the minority from what I have seen. Most of the Metcal stations at work are set up with at least three full sets of tips.Bob

author: nanofrog
author_rank: Super Contributor
timestamp: June 24, 2016, 03:46:55 pm
content: Quote from: nctnico on June 24, 2016, 12:14:20 pmHow many layers can you do this without any preheating though vs. going to the next higher series tips for lead-free alloys?I mean Metcal is definitely great equipment, but it's not the end-all, be-all of soldering equipment anymore, as the performance gap they had when introduced has vanished. Some competitors have even been able to exceed their performance, and many more have stations that are ~ equal to it (13.56MHz models, not the lower performing 470kHz). Some even at a lower cost, such as the FX-951 (based on US pricing).There's also additional tip wear to consider when using the same tips for both types of solder alloys, particularly due to the more aggressive flux formulations in the lead-free alloys as well as rinsing to minimize contamination. And if you've a strict process control procedure in place*, using the same tip for both alloy families wouldn't be possible due to the issues of strange alloy mixtures at the joint interface due to contamination.The latter wouldn't be an issue for a hobbyist, but faster tip wear would be if swapping alloys is done frequently.*Regarding process control, this is one of the reasons Curie Point based technology is so useful, as operators can't adjust the temperatures. Makes it an excellent choice for production rework in this regard, so this technology still has a solid place in the market.Quote from: nctnico on June 24, 2016, 12:14:20 pmI've noticed that as well.But with hobbyists in particular, costs are a much bigger concern unfortunately, and tip costs seems to be underestimated when purchasing soldering equipment IMHO. Take Metcal; their tips are simple, but expensive. Thermaltronics offer lower cost equivalents, but they may not be available or remain cost effective in all markets.For value on tips (cost v. lifespan), I'd have to put Hakko in first place here in the US, including their cartridge T15 series. Ersa might hold that title in the EU/UK market, but they're not common here, so don't figure heavily in such an assessment.

author: nctnico
author_rank: Super Contributor
timestamp: June 24, 2016, 04:01:43 pm
content: Quote from: nanofrog on June 24, 2016, 03:46:55 pmThat depends very much on the size of the thermal relieves in the circuit board. The problem with cranking the temperature up is that the flux wil burn up quicker so yes, at some point you'll need extra heat. For bigger soldering jobs I use hot air (also at 330 deg C).

author: nanofrog
author_rank: Super Contributor
timestamp: June 24, 2016, 06:04:36 pm
content: Quote from: nctnico on June 24, 2016, 04:01:43 pmI was thinking in terms of well designed boards, where soldering was well accounted for, but still present a high thermal demand (i.e. 12 layer graphics cards). Even good equipment can struggle at appropriate working temps for the solder being used, and at some point will require some preheating or other method of soldering (i.e. small oven or hot air rework <thinking in terms of a bench, not production>).Adding more flux will solve the burning off too quickly issue, assuming the temp isn't set at max on a tip that's inappropriate for the joint type of situation (3.2mm pad w/ an iron set to 450C using a 1.2mm chisel or some other ridiculous combination).FWIW, I keep additional flux handy for the situations that call for it. It does make more of a mess, but I'd rather clean up clear to honey colored flux residue than the stuff akin to charcoal.I've a both a hot air rework station and preheater, so I've a couple of options. I do prefer to use an iron where possible, as it's easier to control where the heat goes vs. hot air on a populated board. Can't beat hot air for removing SMD ICs though IMHO, and there are solutions for keeping the heat where you want it if the board is populated (shields).

author: uncle_bob
author_rank: Unknown
timestamp: June 24, 2016, 06:08:57 pm
content: Quote from: nctnico on June 24, 2016, 04:01:43 pmHiOne person's "good design with excellent thermal relief" is the next guy's "not enough heat sinking to the board for the cooling to work" design. There are a lot of cases where heat *must* go into planes on the board.Bob

author: RobertHolcombe
author_rank: Frequent Contributor
timestamp: June 25, 2016, 01:39:57 am
content: Quote from: SteveyG on June 24, 2016, 08:06:38 amWhile true for large components I still prefer having tweezers for small chip components.Also there's nothing stopping you from using the tweezers in either the open or closed position as a normal soldering iron. Having both a normal iron and tweezer is very versatile.