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Comment by liendolucas | Hacker News Reader

Just curious as I'm not into electronics but what is the name of the device where you put the PCB to be heated up? Is it expensive? What are the basic tools to perform full soldering of all components in a PCB? Seems like today you can buy all these tiny resistors, capacitors, chips, etc and pretty much do your own boards at home, right? Any suggestions on all these basic tools to have a relatively decent but not expensive lab setup?

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> Seems like today you can buy all these tiny resistors, capacitors, chips, etc and pretty much do your own boards at home, right?

The "starter kit" I would suggest is:

- temperature controlled soldering iron. This is worth the premium over "dumb" irons, especially for leadfree solder. People have different opinions about brands, but try Hakko or Weller. Start with a small chisel tip

- solder paste is a more advanced substance, and is perishable and should be kept in the fridge. Stick to a reel of thin solder to get started

- flux pen is surprisingly useful

- resistors are cheap enough that you can just buy all of them: https://www.aliexpress.com/item/4001321720241.html

- ICs you should stick to Digikey or other local supplier and NOT aliexpress

- PCBs: services like JLPCB will make these and ship them to you

- desk lamp. Possibly one with a magnifier.

- some people will get serious about fume extraction; personally I quite like the smell of flux and just leave a window open. Be careful with airflow in case you blow away smaller components

- solder braid: annoying, doesn't work well. Try a solder sucker

- advanced but extremely useful tool: solder tweezers

- hot air gun and/or oven: again a more advanced tool, but critical for certain parts. Avoid those parts.

Solder wick: can really work if you have decent quality wick, either rosin-impregnated or add flux when using. Also I've found it really helps to add some fresh solder to whatever you want to desolder, before using wick. I learned that from watching the YouTube channel "Learn Electronics Repair".

- simple boards can be made by first transferring your PCB design to a copper-plated board using toner transfer or UV exposure, then etching the rest of the copper away using an etchant solution (if you're willing; takes some elbow grease and dangerous chemicals). Or you can get a cheap fab-house to manufacture and ship you something (like 7-14 days, a few tens of bucks per batch)

- simple boards you can probably solder with a cheapo (~50-100$) soldering system, or a solder-paste+hot air machine setup

- components you can get for very cheap from LCSC, aliexpress or at okay prices but good reliability from digikey, mouser etc.

You'll also need stuff like multimeter, ocsilloscope, logic analyzers, etc for debugging your boards but you'll know when you need them, and there are cheap-enough options available up to the point when you start doing advanced stuff and you know what you need.

For most SMT repairs, we use a pair of these hot air guns[0] and one or two Hakko Omnivises[1].

A 3/4" copper pipe elbow JB Welded on one of them turns it into a 90 degree bottom-board heater and other is waved by hand over the top of the board.

Nearby parts can be protected with a little Kapton tape or other heat resistant shielding.

[0] https://www.amazon.com/gp/product/B0752Z4165

[1] https://www.amazon.com/gp/product/B000B61IHW

It's quite feasible to do reflow soldering by applying solder paste with a stencil and then using a cheap toaster oven. However, the lack of a precisely controlled temperature profile makes it less repeatable and reliable than the industrial process. I've done it successfully a few times but generally had to touch up one or two components with a hot air station or soldering iron.

Here's a SparkFun blog post: https://www.sparkfun.com/news/3319

Reflow oven

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