Recapped, newbie needs second opinion

[Pat the Cat]

Not too shabby. You've got some big blobs that look a bit dry (pic with u34). A bit of solder wick and heat to soak up the excess would help.

I'm guessing you used lead  free solder, which isn't what Commodore used. Makes for ugly joins, although they do work. A little flux can help.

The thing should power up with no capacitors at all, it doesn't look like you damaged anything.

And DO give all the new joins a wipe with isopropyl alchohol, it's not good to leave flux on the board.

Doing that before you solder helps get rid of grease and muck and makes the job tidier.

EDIT: Really, to do a proper job, you have to take the bottom metal shield off and solder on that side. Got a 5mm nut spinner?

[Pat the Cat]

Thought so. You DEFINITELY want to take the shield off and check the bottom.

Molten solder could have run down and blobbed a short on the underneath.

I'll take a look at that pic and get back to you in a few minutes.

[Pat the Cat]

Memory card looks OK apart from the switch. It probably turns the thing off, it it doesn't work (try later, MUCH later) then a spray of switch cleaner might restore it or it might need replacing.

Check it with a meter but the battery gunk can eat the inside of the switch.

I cant see really bad corrosion on the tracks, looks like the mask kept the gunk at bay long enough for you to take off the battery.

DO NOT APPLY POWER until you have checked over the rear of the board. Lead free solder is muvh higher temperature to melt than lead solder, so you chances for a run down blob are very very high.

They call it "though hole" for a reason.

[Pat the Cat]

OK, if you're happy there's no bridges, fair enough.

First attempt, you just want to see if the power LED turns on before you turn off quick.

No rising pillars of magic smoke? No fishy smell? Turn it on and leave if until  you get a boot screen.

The reason I wasn't happy with the U34 cap was the big ball of solder looked very dully. Very dry, not properly melted.

Usualy a switch has zero resistance between the middle pin and one of the outer pins, flipping to the other when you flick the switch. Easy enough to check with a multimeter, don't plug it in when you test it that way.

Do plug it in the right way. Upside down it will fry your Amiga.

If you're going to do more of these, do get some real lead solder (look for Pb included), you can find small lengths of it on places like Amazon and Ebay "For DIY use".

All about practice.

[Pat the Cat]

For checking the pins on the expansion, what should I have the multimeter set to? My knowledge in electronics is very limited as you might understand by now

Ohms, resistance. If a switch is working, there should be 0 ohms (or very close to zero). If a switch is open, it shows as one (blikning, very high resistance).

Powered the A500+ without monitor, green LED lights up and it makes lovely floppy sounds
Tried booting from a floppy and it seems to load. Feels promising

Good. The monitor sounds very ill.