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Comment by pkaye | Hacker News Reader

They need to be designed to be easier to repair too. To replace a thermal fuse in my dryer requires that I take apart half my dryer. They could have left it behind some panel in the back.

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Same with electric toothbrushes. They lodge the battery in between electronics, probably because they realized people were replacing them.

Philips tooth brush is the opposite: they even warn you that at some point you will have to replace the battery and how to do it.

Which ones? Oral-B/Braun toothbrushes make the battery removable on the bottom for proper disposal (it's not really replaceable though, though that can probably be done, but it's not the intent of the design).

I smashed the glass top of my Kenmore (Frigidaire) stove and I was surprised to discover that the fix was almost trivial once I got part. It was not cheap, admittedly, but at $250 it was still much cheaper than a new stove.

Honestly, that's the one aspect of the Kenmore stuff that really impressed me. There was lots of good information out there on what parts to buy and how to do the fix.

Small tidbit, but I am delighted when I find boards that still use through-hole components or chip sockets. Apart from cellphones, you often don't really need the extra space.

BGA are the hard ones and virtually not doable for a home gamer, the rest are fine.

Imo, through-hole are worse, harder to remove than SMD if you have hot air.

(edit) What is actually necessary for electronics - "schematics" and datasheets. It's quite hard and time consuming to trace stuff, esp. on multilayered PCB. Lack of datasheet is even harder to overcome in many cases.

Through-hole is easier than SMD with the correct tools. Specifically a vacuum desoldering tool (Metcal MFR, Pace SX or similar).

Until you pull a pad through on a $20k multilayer board. Been there.

Give me straight, well designed and BGA-less SMD any day. Also Metcal user here.

I think you meant 'via'?

The via yes. That's attached to the pad on the other side which is what I'm referring to. The first "oh shit" moment is when you see the pad attached to the leg of the part.

Not really, no. It's really nit-picking, but a "via" is a (usually small) plated-through hole that is used solely for connecting traces on different layers of the board. I'm pretty sure the term isn't normally used for the plated-thru holes with pads that are used for thru-hole parts, even though the construction of the two is almost the same. The main differences are that the holes for PTH parts are usually larger, and the pads around them are larger, for better soldering. Vias don't need much of a pad around the hole because you're not putting solder in the hole, and vias are usually covered with soldermask.

Yes, really, yes. It isn't nitpicking when you're simply wrong. Via's are vertical interconnects between layers, they can be 'blind' vias which do not connect to either top or bottom layers or regular ones.

https://en.wikipedia.org/wiki/Via_(electronics)

If you're going to call someone wrong, then you should check to make sure you're right first. But you aren't:

https://en.wikipedia.org/wiki/Through-hole_technology

"Plated-through holes are no longer required with SMT boards for making the component connections, but are still used for making interconnections between the layers and in this role are more usually called vias.[2]"

Even your own link says nothing about PTH, and just discusses vias for use in SMT.

Except that the context was through hole boards.

> "Through-hole is easier than SMD with the correct tools. Specifically a vacuum desoldering tool (Metcal MFR, Pace SX or similar)."

I'm all over the place -- I've got an Aoyue hot-air station, a Metcal MFR soldering station and a Pace SX90 vacuum desoldering rig. :)

Whatever I can get for cheap, basically. Home hobbyist :)

BGA is doable, just a bit more work. Just be very careful with your prep work.

Depends on the BGA; the extremely high-density ones generally require special tools. They're also nearly impossible to inspect without special camera equipment. The really low-density ones (like DFN) are pretty easy for a hobbyist though, but in general BGAs should be avoided for designs aimed at hobbyists. You can get away with repairing them sometimes, using a reflow oven (made from a toaster oven), or even a hot-plate, and it is possible to re-ball them at home, but I wouldn't count on this as a reliable thing.

"BGA at home", I'd never touch that. A person w/o experience and/or rework station is likely to meet frustration only. It's a futile effort in my opinion.

The inspection part is bang on - what if there is a short and it just burns the traces. Now the thing is not repairable even by a professional repair service.

I am just a programmer... totally for right to repair, open schematics, easily to source components, etc. I can repair electronics, incl. SMD soldering on laptops, LED light fixtures, diagnose home appliances but I'd not touch any BGA. Or heat pump water/fluid subsystem or high pressure vessels -- and I'd prefer if I'd buy a house with any of them installed not to have been repaired w/o care and experience.

I thought that way as well, now unless we are speaking of DIO socketed ICs SMD is faster and easier to desolder and it is harder to lift pads while doing so.

That beeing said, SMD is different. It is like — well — learning soldering once again from the start. The only thing really harder is seeing the parts.

> only thing really harder is seeing the parts.

Get a 5X binocular microscope. You can get a budget model for about $200.

Once in college, I hand fabricated a board some other students designed with SMT bits. I've always been near-sighted (use glasses to see far) and have developed a habit of taking my glasses off when I'm in a room to keep my nearby surrounding clear. For this board when I was populating it, I of course used a magnifying glass to see the parts, but after finding it cumbersome, at times I would find just focusing hard enough to see the little bits was quicker although requiring some effort.

Thru-hole components are horrible, and I'm glad they've mostly gone the way of the dinosaur. Not only are they huge, they're harder to replace and frequently result in damage to the PCB. It's not too bad for resistors and capacitors, but ICs are the worst; the safest way to remove those is to use diagonal cutters and cut all the legs off the chip (destroying the chip of course), and then use your iron and a spring-loaded solder-sucker to remove the legs and the solder from the holes. You can forget about non-destructively removing an IC so you can re-use it. Sockets suck because they fail eventually, due to corrosion, thermal cycling, etc. Gold-plated sockets help, but these are expensive. And yes, the space is significant with PTH components.

Surface-mount stuff is much, much easier to work with. The catch is that you need a hot-air rework station, but you can get a very decent Chinese-made one for less than $200. With one of these, you can easily replace SOIC/SOJ type ICs. The ones with 0.5mm lead spacing are very easy to work with; you can use some tweezers and a hot-air station to replace these chips easily, and just assembling a PCB with them is easy with a regular iron with a fine tip.

A thermal fuse isn't a routine consumable. Those are designed to trip when something else is wrong. You need to open it up anyway to fix the root cause or confirm it was a fluke and there is no pending safety hazard.

this goes for all machines, i read recently that modern tractors are impossible to repair by farmers due to manufacturer restrictions.

I'm not so sure about this. For John Deere tractors, definitely; there's lots of articles about this. For foreign brands, it may not be the case at all.

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