Recap Amiga 1200 necessary?

[Nick_66]

I do have a good soldering station with a couple of soldering tips. One is a very sharp tip and a bigger (flat at the end) one. I can regulate the temperature of this station. I also have a suction pump and litz wire.

Can I reach the soldering tabs of the cap on the circuit board? Do they stick out underneath the piece of plastic?

[DirtDevil]

Here's a nice start-to-finish of (one method) replacing SM caps
 
 https://www.youtube.com/watch?v=mjCa0DAEpzQ

[sim085]

Great video. I too am looking to do this myself. What is the gel used at 2:30 of the video?

Here's a nice start-to-finish of (one method) replacing SM caps
 
https://www.youtube.com/watch?v=mjCa0DAEpzQ

[spaceman88]

Great video. I too am looking to do this myself. What is the gel used at 2:30 of the video?

Solder paste. Solder and flux mixed together.

[hirschma]

I saw on Youtube somebody showing how he did a recapping of his A1200 and to remove the old caps he turned them a couple of times with a gripper (is that the correct word for this tool?) to remove them from the circuit board. Is this the best way to remove them?

I run an electronics assembly line - and as others have said, DO NOT DO THIS. You will end up tearing pads off the board.

Hot air tools are the best way to go, and you can find them cheap on Amazon or eBay. Cover areas that you don't want to affect with kapton tape.

[Zylark]

Here's a nice start-to-finish of (one method) replacing SM caps
 
 https://www.youtube.com/watch?v=mjCa0DAEpzQ

That video do indeed show the proper way of doing recap work. However, it is also done using quite specialist tools.

Like the hot tweezers, which your garden variety enthusiast and hobbyist have no good reason to throw money at. You can though achieve much the same effect using two soldering irons. Just make sure both can reach good temperature (at least ~350'C / 670'F) *AND* retain heat well.

I use a Hakko soldering station with a beefy chisel tip (3mm i think) and a cheap as dirt 30W 'all in one' soldering iron with a similar chisel tip. Just pre-tin the cap with a blob of solder on each side for better heat transfer, get the irons in there and see the solder melt and simply tip away the cap. Easy as icecream and 100% safe for your Amigas precious pads. Every time an Amiga pad is torn, a kitten cries! Clean the pads with a touch of flux, solder-wick to suck up the remains and then rinse the area with isoprop and a lint-free swab or tissue.

As for attaching new caps, again the video is very proper and professional. And again it is using something an enthusiast won't have just lying around usually - solder paste. solder paste is fickle stuff that cost quite a bit _and_ got an expiration date of about a year after manufacture, assuming you store it in the fridge. Solder paste is great for SMD reflow work, but to justify buying the stuff, one better do quite an amount of SMD reflow work.

Another method is to just use a bit of flux and good old solder wire. Add  a drop of flux to one pad, then place the cap the way you'd like it to go. Keep in mind that electrolytics are polarized, so it do matter which way round they are attached.

Anyhow, with the cap in place and the drop of flux on the one pad, melt a little solder on the tip of your iron to create a tiny blob of solder on it. Now use this blob to 'tack' on the cap on the side where you applied the flux whilst you hold down the cap with some tweezers or similar so that it do not move about. Once done, clean the tip, and solder on the other side properly. Then move to solder on the first side properly. And done.

Next cap please!

[Nick_66]

Just found something on the internet. It's a SMD tweezer soldering iron:

SMD tweezer

It's affordable but will it work?

Or this one?

[Acill]

Just found something on the internet. It's a SMD tweezer soldering iron:

SMD tweezer



It's affordable but will it work?

Or this one?

I use a Weller $200 set and they are my favorite tool. Work amazingly well as long as you know how to use them properly.

[Zylark]

Just found something on the internet. It's a SMD tweezer soldering iron:

SMD tweezer

It's affordable but will it work?

Or this one?

They both seem a bit anemic. The top one only 20W per element, and the bottom one a smidge better at 25W. Add to that the rather thin tips, and you have pretty poor heating power coupled with pretty poor heat mass and heat transfer surface.

They may be perfect for lifting off small components such as resistors and ceramic/tantalum caps. But the electrolytic SMD caps have significantly more heat absorption mass. Maybe even so much that those hot tweezers will either struggle or fail at removing them altogether.

Have you looked into getting some quick chip solder? With it you can lift off SMD components using just a (good) soldering iron. Cheaper than hot tweezers too. Or, do as I do, use two soldering irons.

[smerf]

LOL!!!! Proud Navy Retired Chief

Didn't know Chiefs knew how to work!!!
You know how to use a Pace?
Didn't think a Chief could do that

[smerf]

Hey Chief,

Is that a 150 watt or 200 watt soldering iron.

Oh, I could go on with this, but,
How you doing Chief, old HM-15 Alameda giving you harrassment. Retired there and then moved to Florida, told Ca. I would pay their stupid taxes if they kept the roads open long enough for me to get out of their and back to a good state. Then as the situation would happen had to move to Pa. Only difference between Pa and Ca. is that Pa. has very cold weather. Now getting ready to move once again.