Soldering hints

[cypher007]

thought id just add a tip, not sure if it hasn't already been said.

when doing my a1200 recap I used foil tape, the stuff you can buy in wikes etc. its for taping up pipe insulation, so its sticky one side. it seems to fix components under it so they don't blow away, and deflect or spread the heat so you don't start getting other components and plastics melting.

[Wayne123]

I started to recap my Amiga A500 and was having trouble removing the two big 3300μF caps on the board. Did they glue down some of the big caps or did I just catch some early leakage holding the part? When I pulled the caps it left some of the bottom of the capacitors case stuck to the board.

[idrougge]

It is quite common for large components to be glued down.

[Wayne123]

Originally Posted by idrougge

It is quite common for large components to be glued down.

Thanks, I was hoping that was the case.

[TTSAddict]

I've got only two things to say:
1. Rosin is your friend!!
2. Don't breathe the fumes. A cheap fan ripped from a PSU or whatever can be used as a simple fume extractor if even just to move the fumes away from your face.

Built this stand from an old PSU fan and cardboard. With a little creativity, you could also add a carbon filter mat on the back.

[solidcore]

For those who want to save money and are looking into 'smd soldering' my post is for you, those who financially better off and can afford a soldering station this post doesn't apply to your budget although it may be helpful I hope.

I started through-hole soldering around Sept 2017 (Nes famicom AV CPU/PPU replacement with hdmi kit) with a 10 quid iron (40 watt) and later in 2017 Oct/Nov I bought a '555' LED Kit off ebay for 2-3 quid and some flux pen. Yep that's all it takes to get your butt over to SMT soldering on the cheap... granted you'll be buying a cheap pcb with cheap chips and cheap leds/resistors but let's also appreciate the budget level entry here... we get to mess up with cheap parts before we take on a bigger deal later, and this is where confidence and experience start to take a hole at little risk to you - my partner even had a go, so with a little guidance and flux and despite never ever holding a soldering iron before she managed to solder a 8-soic in no time , so you can too!

I later learned that the flux pen was absolutely wack, it ran out quickly and did a very poor job I was recommended to try Rf-800... long story short rf-800 is cheap, lasts a long time and has high performance results and best of all it cleans away quite easily with Isopropyl and a good quality kitchen paper is essential to soak up the flux/propyl and you won't get far without a paint bush either, keep it clean though it can gunk up over time!

Now I know the disadvantage of using a low wattage iron which probably is a piece of crap at the end of the day is that you don't know the temperature you're working with but the other advantage is it's piss poor and won't let you do too much damage provided you're not going to abuse your poor pcb with it - ground planes are a nightmare with a cheap iron and that's something you will consider when recapping an a500 but for smd work this doesn't actually apply here, or rather I fail to think where it would. A bigger tip actually works better than a smaller tip for SMD bigger tips distribute across the pins which allows you to drag solder more efficiently than a tiny tip which would distribute heat to a smaller area, which effectively will make it harder.

I'm going to continue using my cheap iron for all projects big and small because quite frankly it works for me, so don't be intimidated by the huge costs of solder stations etc it's not critical and will not give you '1337 skills' either, it's all about your confidence and your experience and that's the key factor in my opinion.

Other great handy tools are:

- a pair of tweezers
normally i use my fingers for IC's but tweezers for resistors/caps/Leds etc...

- Engineer Ss-02 with silicone nozzle
absolutely brilliant! compared to the plastic tips

- jewelers lens
required for smd, for hunting shorts/ poor solder joints, and to inspect your lovely work!

- cheap fume extractor
required, flux/lead solder is horrible don't breath it in, toxic dangerous makes you sick... you know the drill

- brass wool
amazing stuff, buy 5 of them off auction site for cheap and put them in a old jam jar better than a wet sponge, clean tip, keeps it healthy longer.

In all you can get all the above for less than 30-50 quid shopping around on auction sites. Any questions feel free to PM me I am happy to help anyone starting out, I was a newbie too and still learning, always learning!

[nogginthenog]

I have a cheap soldering station and it's surprisingly good:
https://www.ebay.co.uk/p/Katsu-936-D...087/1378510000
£24.99

Big Clive review here:
[ Show youtube player ]

A jewelers lens/loupe is great. Get one with built in leds.

Stainless steel kitchen scrubbers are also good for cleaning.

[puppypc]

I recommend this video to understand how, when, and why to use flux in soldering jobs

[ Show youtube player ]

[nogginthenog]

Originally Posted by nogginthenog

I have a cheap soldering station and it's surprisingly good:
https://www.ebay.co.uk/p/Katsu-936-D...087/1378510000
£24.99

BTW, I was in ALDI today and they had a solder station for £19.99. It appeared to have a temperature control, but the iron was huge! Like the size of a regular soldering iron. Cable seemed fairly flexible though.

[Solderbro]

https://www.reichelt.com/de/en/Solde...&ARTICLE=90918

A million seller for industrial business, solid quality, good price. 4 Tips for under 10 euros, have it since many years with pretty results.

[salteadorneo]

A JBC soldering station and a hot air 8586 station. I'm looking for some decent rafter.

[Flimbo]

I am looking to purchase my first soldering station and want to spend no more than £50 ($65). Would appreciate any advise on current equipment.

I also want to thank everybody that contributed to this thread, it is such a great resource for folk starting out like me.

[Lektroid]

I'm no expert, but no spring chicken. I have been working in electronics since the late '80s, my contracts included avionocs (aircraft communication systems), electronics for the digital TV infrastructure in the UK, not to mention being a test engineer at Commodore in Peterborough. Happy to share a couple of tips, someone may find them useful.

I have a couple of Weller irons on my bench, it's good to have two irons when removing 2 contact SMDs, a soldering iron at either side of the component will quickly lift the part off. Removing anything bigger than 2-pin parts, use a hot air rework station, they're pretty useless for soldering, but great for multi pin part removal - including 40 pin through hole ICs. I also have a TS80 for field work away from the bench. If you don't have a low voltage iron like the TS80/100 (which I would highly recommend), Always use a station (never a direct to mains), not only for a well regulated temperature, but reduced voltage leak at the tip.

You should never need to go over 350ºC on any board, if you do, you run the risk of lifting pads/traces. If you find you need to go over, your iron has poor heat transfer efficiency, this can also be down to poorly maintained tips. Tip life can be hugely extended with auto standby on your iron which drops the temperature when not in use (in case like me you are forgetful and often leave your iron on).

One thing I notice is folk talking about the fumes from lead solder, firstly there is no way on this planet you'll be able to reach the temperature required for lead to evaporate with a any sort of off the shelf soldering iron, the toxicity comes from the rosin flux. That said, liquid flux is great for tidy factory finish joints, and essential for tight pitch SMD ICs, but can make the PCB sticky, so have some isopropyl on hand.

Always use lead solder (60/40 or 63/37) when repairing or reconditioning older machines like the Amiga, C64 etc. (I also do a lot of vintage synth repairs). It's very rare for pre-RoHS units to use lead free solder, and the two types do not mix well and have different melting points (lead free is usually higher and thus you run the risk of messing your board up.

These are just a few tips off the top of my head, but if I think of anything else, I'll post it here, hopefully you'll find something of use if it's not already been mentioned (I've not read the whole thread).

[Lektroid]

Just to add, I've had a private message mentioning the use of lead solder, here's a few points to think about when choosing your solder.

Lead was added to tin solder in the 1950's to prevent tin whiskers, which can cause arcs and shorts on fine pitched ICs. When lead is removed, an alternative is to use conformal coating on PCBs to reduce tin whiskers, but very few manufacturers use conformal coating on their PCBs to save money since it's not mandatory, meaning many modern electronics, TVs, consoles / computer hardware, phones etc. have a reduced lifespan, usually long enough to safely get through the warranty period, this is otherwise known as planned obsolescence. However, now we have a problem with vast quantities of modern electronics on the landfill.

Interestingly, there is a directive restricting the use of non-RoHS in consumer electronics, yet lead solder is compulsory in certain industries, such as medical, aviation, and military for higher reliability.

[MrClump]

Can anyone suggest a good source of decent quality tin lead solder? I've just bought a 100g reel on eBay and it was utter garbage; don't really want to be buying the large reels the likes of RS Components sell.

[ajk]

Mouser carry all sorts, Digikey should have about the same selection. ChipQuick also have all kinds of small spools.

[MrClump]

Originally Posted by ajk

Mouser carry all sorts, Digikey should have about the same selection. ChipQuick also have all kinds of small spools.

Thanks, I've ordered some Chipquick from Mouser.

[Lektroid]

Originally Posted by MrClump

Can anyone suggest a good source of decent quality tin lead solder? I've just bought a 100g reel on eBay and it was utter garbage; don't really want to be buying the large reels the likes of RS Components sell.

Most come in 500g reels, occasionally you can get 250g. I go through 500g every couple of years, but I do a lot of soldering. I usually buy from CPC or Farnell, not sure what they're like for smaller quantities.

[Eamoe]

Pay attention to debris around the working surface. If you encounter weird problems, check every place around and under the chips and sockets. Look for metal.

Many years ago I scored a rev 6.3 A2000 in very good condition. There was very mild battery leakage, which I properly cleaned and then I revarnished exposed traces.

It's a project I've been in and out of ever since, occasionally buying pieces of hardware and keeping it on the side, slowly collecting devices with the intent of making a great A2000 build sometime in the future. Hopefully before retirement.

In november of 2018, I completely recapped the motherboard. I got the Amiga to boot from an SD card controller attached to the SCSI controller. I was really happy, but then suddenly it started giving nothing but black screens. On rare occasions, I'd get a color. Sometimes green, or red, or purple...

Since then, whenever I got some spare time, I'd get to it and try something. I did everyhing, changing every single chip individually, reading schematics and checking continuity from every socket pin to destination, Nichicon-recapping the PSU, trying another PSU... This took very long, as you can already tell from my rythm of work.

Two months ago, I decided to change the CPU, ROM and Agnus sockets. I was medievally pulling out the last one of those, the Agnus one, and as the last bits came off, I noticed a small piece of straight silvery wire which had nothing to do there.

What happened was, a cut off leg from one of the replacement caps back in 2018 had escaped somehow and rolled right under the Agnus PLLC! It had been tucked down there ever since, wreaking havoc shorting several legs of the chip together...

A 2-year long fix. I hear your laughter from where I sit. I don't care. I did it. The Amiga works!

[amigasith]

Originally Posted by Eamoe

A 2-year long fix. I hear your laughter from where I sit. I don't care. I did it. The Amiga works!

I for one am not laughing. I found it a very nice, interesting, and motivating story Hats off to your endurance!