Low temperature solder paste - Page 1
Forum section: electronics / general

author: Simon
author_rank: Unknown
timestamp: February 19, 2019, 10:35:19 am
content: So I see that I can now buy 138C melting point solder. What are the downsides? i take it I'd have to be careful with working temperatures of the assembled board? At what point would it soften?Sounds like a paradise for making prototypes and let the assembler use the regular 180-220C stuff.

author: Ian.M
author_rank: Super Contributor
timestamp: February 19, 2019, 11:23:30 am
content: As you haven't specified which solder alloy you are proposing to use, no one can answer those questions. However, assuming its a SnBi based alloy, there are probably answers to be found athttps://www.indium.com/solders/bismuth/Frankly it sounds like a PITA unless you have very temperature sensitive components. Eutectic SnPb hand soldering and bench top reflow for prototyping are well solved problems.

author: Simon
author_rank: Unknown
timestamp: February 19, 2019, 11:27:11 am
content: Sn42/Bi57.6/AG0.4

author: I wanted a rude username
author_rank: Frequent Contributor
timestamp: December 27, 2019, 02:15:06 am
content: Quote from: Ian.M on February 19, 2019, 11:23:30 amBecause it doesn't wet as well, is more brittle, or some other reason?We all love leaded solder, but if you have to use lead-free, the lower temperature of the bismuth alloys seems like an advantage ...

author: jmelson
author_rank: Super Contributor
timestamp: December 29, 2019, 05:54:05 pm
content: Quote from: Simon on February 19, 2019, 10:35:19 amCheck the fracture strength of this stuff. We had some temperature-sensitive parts, and got some of this solder. Well, it was completely unusable.You'd solder the parts, let them cool, and you could flick the parts off the board with your fingernail! Microscopic examination proved the solder pastehad properly melted and reflowed the joint, but it had ZERO mechanical strength. We ended up using tin-lead solder at the minimum temperatureand duration possible, and all was well.Jon

author: GeorgeOfTheJungle
author_rank: Super Contributor
timestamp: December 29, 2019, 06:08:24 pm
content: Isn't that what chipquik is made of?

author: SeanB
author_rank: Super Contributor
timestamp: December 29, 2019, 06:13:38 pm
content: Simon, what do you think Chipquick solder is, other than this, as said by George (watch out for that tree) as well. Probably only really useful for ultra sensitive parts which cannot be soldered otherwise, and where you have other mechanical support for the components other than the joint. About the only application I can think is for metallised foils in microphones, or glass soldering to an ITO film.

author: Simon
author_rank: Unknown
timestamp: December 29, 2019, 10:51:56 pm
content: this is an old thread that was dragged back up by a spam poster. I elected not to use the low temperature stuff.

author: I wanted a rude username
author_rank: Frequent Contributor
timestamp: December 29, 2019, 11:18:41 pm
content: Quote from: Simon on December 29, 2019, 10:51:56 pmThat's a serious accusation, mate. Where's your evidence of the alleged spam?

author: Simon
author_rank: Unknown
timestamp: December 30, 2019, 09:08:17 am
content: I don't owe you any proof. As moderator I deleted it but it meant the topic rose to the top of the list again whereas i was happy to say it was over and I was satisfied with the answers 10 months ago......

author: I wanted a rude username
author_rank: Frequent Contributor
timestamp: December 30, 2019, 10:09:30 pm
content: I was the one who bumped this post from a search, not wanting to beat a dead horse. Thus it would seem to a reasonable person that you were accusingmeof spamming ... in which caseyou would indeed have needed to provide evidence.Of course, it's possible that there was a spam post which was low-level deleted without leaving the usual "This message has been deleted" notification.Regardless, the subsequent answers have been elucidating.

author: Simon
author_rank: Unknown
timestamp: December 30, 2019, 10:46:44 pm
content: Why do you make such a fuss? I have not accused anyone in particular of spamming. Often a spam post bumps an old topic. You seem to have decided for yourself how spam works! so tell you what i will tell you. A blatant spam post will be deleted (by me) completely and the user banned with no trace left. It could be that I was mistaken if you say you bumped the topic in which case that is fine if you wanted to continue the topic maybe i am thinking of another topic i got a report about at about the same time although it seems not you are just having a silly argument over a throw away comment! Now was there anything you wanted to discuss abut low temperature solder?

author: lawrence11
author_rank: Frequent Contributor
timestamp: December 30, 2019, 11:14:29 pm
content: I think that you Simon are an annoying mod.You shitted on a 3 phase circuit I made.

author: Simon
author_rank: Unknown
timestamp: December 30, 2019, 11:16:30 pm
content: Quote from: lawrence11 on December 30, 2019, 11:14:29 pmAnd I'm supposed to give a shit? Your opinion counts very little. I don't even know what circuit you are talking about.

author: lawrence11
author_rank: Frequent Contributor
timestamp: December 30, 2019, 11:18:14 pm
content: https://www.eevblog.com/forum/renewable-energy/anyone-feel-like-reverse-engineering-this-patent-app/remember this?I'm just asking ppl a question.

author: EEVblog
author_rank: Unknown
timestamp: January 10, 2020, 08:11:41 am
content: Quote from: I wanted a rude username on December 30, 2019, 10:09:30 pmThere are two ways for a moderator to remove a post. One using a plugin that replaces the message with "This message has been deleted", and the standard built in SMF option of simply removing the post without a trace. We use the latter for most spam posts as it prevents the forum getting filled with "This message has been deleted for being against the rules etc" posts.

author: Simon
author_rank: Unknown
timestamp: January 10, 2020, 08:45:05 am
content: Put it this way, the guy that raises this is only here due to my good nature. Anyone else would have banned him for his vulgar user name when he signed up which was quickly reported to me. I tongue in cheek changed the display name and let him stay. I'm not sure many other forums would have bothered and a tick box moderator would have just deleted his account which on SMF bans the email from being used again.