Pros and Cons of Low-Temp Solder Paste - Workbench Wednesdays

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#0:00 Welcome to Workbench Wednesdays
#0:40 Low-Temp Solder Paste
#3:10 Low Temp Paste Pros
#5:53 Low Temp Paste Cons
#8:10 Give your Feedback

#Soldering #Hardware #Tools #SolderPaste

[markharrisllb]

I’m a rank amateur who's a danger to society with a hot air gun. I managed to move 4 SMDs from an Arduino Nano the first time I used one. Low melt solder has been a life saver for me, I can work confidently at lower temperatures when trying to fix my mista… I mean things the manufacturer got wrong.

[brandtharen]

Interesting, as a home hobbyist I always assumed that low temp solder was lower temp than lead free solder but still higher than leaded solder. I'm glad to know better now.

[John_Smith__]

Bismuth when mixed with Lead drastically reduces the melting point. I do not remember the eutectic mix of Bismuth and Lead but in some cases the melting temperature can be as low as 90C ! Actually those solder removing pastes used to help on component removal are exactly that, a mix between Tin Lead and Bismuth.
So one needs to be very very careful when using Bismuth bases solder since the solder iron for example an contain leftover Lead solder ... the mix would substantially reduce the melting point on the solder components.

[andywest]

Awesome video! I like using bismuth-based, low-temp solder to remove components from boards. This reduces the chances of destroying pads by overheating.

[taccomaker]

Wow, that's the first time i heard of bismuth based solder paste. I'm a professional, and at work I only use leaded solder wire, even for small smd components. I prefer it over solder paste, as it doens't really have a shelf life. This definitely changes my opinion concerning lead free alloys, I simply prefer lead.

[aidenryan]

I do motherboard repair on mainly iPhones. All of this is super important for reballing ic's and running jumpers on torn flexes. Need to master your temp control to do stuff that small! Nice video!!

[rundrish]

Very interesting. I have only tried wire solder before.

[hectortd]

Very straight forward explanation

Thanks for the video!

[AndrewGillard]

I've not tried it yet, but the reflow temperature of bismuth-based paste being only slightly higher than my 3D printer's heated bed during ABS prints gives me ideas 🤔
I'm not suggesting the heat bed would do all the work, but it could maybe act like the initial stages of a proper reflow profile, and then a hot air gun could push it over the edge... (I mean a temperature-controlled soldering station hot air tool, not one of the 2kW paint-stripping things, to be clear.)

That seems like it'd give more consistent results than the hot air tool alone, especially for things like exposed pads on QFNs or ESP32 modules, and might cause fewer melted connectors and switches 👀

(Obviously something like a hacked toaster oven will give better results than what I describe here, but I'm not at that stage yet! This is an experiment in whether I can get improved results _with equipment I already have_ :))

[raym]

Is there a build video on your reflow oven?

[mikex]

You are an excellent instructor. Will b buying this from MG.
Thank you.

[butterflywing]

Low temp solder is great for sensitive chips. Reflow first with SAC and then finish sensitive stuff with the low temp.

[sdca]

This question may be out of your wheel house, but I am going to ask anyway. I have a Jeep vehicle that has the rear window glass defroster grid. Jeep has a common problem with the electrical connector breaking free of the copper mounting location on either side of the grid. The recommended fix is sort of epoxy that conducts electricity (which doesn't work, mine fell off within an hour after the dealer repaired it), or just replace the glass. You can bet the the connector will come loose on the new window sooner than later.

Do you think this low temp solder could be used to make a permanent repair to these defrosters?

[ElectronsNeeded]

you do realise now you have to made a LED chip cookie PCB to have as a prop :D

[jasonfasick]

Could the low temp solder paste work to reattach aluminum terminal studs to the aluminum base on a 3.2v 280ah lifepo4 cell?

[christophertadeo]

Hey... this actually is informative... 😳👍

[tjenkens]

I need to solder the "wire" (small tab like thing) back onto my rear window defroster. Would I just put a blob on the defroster, push the tab onto it and then use my heat gun to reflow it?

[damensutherland]

I tried to solder ic with bout 1/8 gap and got bridges the solder didnt melt and it was boiling i used soldering iron and it bridged

[TheBawlz]

I have an old timy container, jarlike but tiny. Of dolder paste from china yhe entire things in Chinese, can i mix it up with a toothpick to redistribute the flux? Then use it to solder a wire onto a 12v chord

[ameliabuns]

the brittle thing is a huge minus for me, but hmm i'm very much tempted to cancel my order and switch it to the half price bismuth stuff :P
i'm building a hot plate soldering plate and it can do 260c.