Expired solder paste - Page 1
Forum section: electronics / general

author: lawrence11
author_rank: Frequent Contributor
timestamp: August 17, 2019, 10:09:04 pm
content: So I just received my T5 solderpaste chip-quik from amazon, but expiration date says march 19, 2019, like 5 months ago.Is this even acceptable? What are my chances to get a refund from amazon?

author: wraper
author_rank: Unknown
timestamp: August 17, 2019, 11:04:37 pm
content: It's completely unacceptable. As it is expired, there is also a high chance it wasn't stored properly (refrigerated).EDIT. Expired flux usually is still good enough even after several years. But solder pastes go bad very quickly. Do not expect it still being good after half a year since expiration, even if stored properly.

author: kylehunter
author_rank: Regular Contributor
timestamp: August 17, 2019, 11:35:41 pm
content: Yeah, don't buy paste from Amazon. I tried it in the past. They don't keep them refrigerated or ship them on ice. Make sure you order from somewhere that packages it properly, and have it overnighted.

author: lawrence11
author_rank: Frequent Contributor
timestamp: August 18, 2019, 12:01:01 am
content: Quote from: kylehunter on August 17, 2019, 11:35:41 pmSo what happens now?Can I get refunded?

author: wraper
author_rank: Unknown
timestamp: August 18, 2019, 12:02:47 am
content: Quote from: lawrence11 on August 18, 2019, 12:01:01 amAnd what is Amazon return process for?

author: lawrence11
author_rank: Frequent Contributor
timestamp: August 18, 2019, 12:06:02 am
content: Ok well I guess I got nothing to fear then.I never actually returned anything before.

author: lawrence11
author_rank: Frequent Contributor
timestamp: August 18, 2019, 12:11:12 am
content: Quote from: kylehunter on August 17, 2019, 11:35:41 pmRofl for what price?Should last 6 months no matter what right?

author: wraper
author_rank: Unknown
timestamp: August 18, 2019, 12:26:25 am
content: Quote from: lawrence11 on August 18, 2019, 12:11:12 amFor normal price, likely even cheaper. Only shipping cost if you make small orders might be an issue. For example Digikey and Mouser have free express shipping with free customs procedure once your order reaches certain amount (U$100 for Digikey and C$100 for Mouser). Otherwise Digikey shipping costs U$20.

author: wraper
author_rank: Unknown
timestamp: August 18, 2019, 12:28:01 am
content: Quote from: lawrence11 on August 18, 2019, 12:11:12 amSome pastes become completely useless after 1 month without refrigeration.

author: lawrence11
author_rank: Frequent Contributor
timestamp: August 18, 2019, 12:44:46 am
content: show me your syringe dispenser gear for putting small amounts in a seperate syringe.I do have a template, I even ordered a "framed template" the thing is huge. Now I guess I know what framed means lol.

author: wraper
author_rank: Unknown
timestamp: August 18, 2019, 01:43:06 am
content: I use Loctite GC10 to not bother with taking out from a fridge, warming up and placing it back after job done. One out a very few solder pastes which doesn't require refrigeration. It's room temperature stable and lasts for 1 year. IME Can be used for 2 years since MFG date but tombstoning increases after a few months since expiration date. Does not matter much for DIY one offs though, might never really notice. The issue is you cannot buy it in small syringe, only 500g jar.

author: mrpackethead
author_rank: Super Contributor
timestamp: August 18, 2019, 06:50:51 am
content: Quote from: wraper on August 18, 2019, 01:43:06 amI've tryed to use some in a syringe. It does not work well... I suspect that the attributes that make it great for stenciling, make it annoying for using via a needle.I shared a 50g of paste with someone locally, its not something i'd do as a 'business' but you never know somone might.. But if you are anywhere near some other tronics people, you might be able to 'share' some around.

author: wraper
author_rank: Unknown
timestamp: August 18, 2019, 07:41:23 am
content: Quote from: mrpackethead on August 18, 2019, 06:50:51 amWorks fine with conical plastic nozzles. Also I did not notice solid and liquid separation inside syringe which happens with many other solder pastes. Especially no situation when you squeeze out relatively liquid paste only to be left with 2/3 of initial amount of dry paste which is very hard to squeeze out.

author: techman-001
author_rank: Frequent Contributor
timestamp: August 18, 2019, 07:41:57 am
content: Quote from: lawrence11 on August 17, 2019, 10:09:04 pmWhen I was doing SMT back in 1990 we used 1.3 Kg solder paste cartridges and each one had a expiry date on it which was 3 months from date of manufacture. One tube usually lasted a day to a few days at our plant depending on the quantity of product we were making at the time.Any tube exceeding the 3 month date was binned immediately because the risk of tombstoning and QA failure was far, far more costly than a new tube of solderpaste. Having a good supplier history was vital in that industry because all SMT components have a 'use by date'. They're like groceries!So basically if your solderpaste has no expiry date on it, its rubbish and even if it has, that date assumes refrigeration which you can't verify when buying small quantities.Then there is the fact that most Chinese resellers wouldn't know the difference between solder paste and a phase locked dipthon retarder.

author: mrpackethead
author_rank: Super Contributor
timestamp: August 18, 2019, 08:39:39 am
content: I'm using the catridges, i get a box of 10 every 2 months or so.. I'm keeping them in the fridge, probalby not rquired, but once it comes out of the fridge it does'tn go back till its used up.I'm a cheap skate some times, but this is one thing i wont' cheap out on.

author: techman-001
author_rank: Frequent Contributor
timestamp: August 18, 2019, 08:50:02 am
content: Quote from: mrpackethead on August 18, 2019, 08:39:39 amI'd put unused back in the fridge, I think we used to do that if there was ever any left, but using that amount of solderpaste you'd be the one to know what works and what doesn't from your own QA inspections as they come out of the Reflow Oven.Solderpaste is a PITA I know, get it just right and the boards come out of reflow spick and span, no cleaning needed and everything neat as a pin.Get it wrong and it's Dodge City, tombstones everywhere or at the very least a frigging mess of flux that has to be cleaned in the boiling flurocarbon bath!With the high price of solderpaste tubes the temptation to save money is strong, but fight the dark side Luke, fight it!

author: mrpackethead
author_rank: Super Contributor
timestamp: August 18, 2019, 09:14:02 am
content: Quote from: techman-001 on August 18, 2019, 08:50:02 amGiven it only sits out of the fridge for 7-10 days, its just easier to leave it in the printer. a 600g catridge makes a LOT of pcbs, and while i should, i dont' even factor it in as a 'component' cost, as its just a tiny line itme.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: August 18, 2019, 09:44:46 am
content: Paste life varies a lot by brand - I've had EFD stuff several years out of date be just fine, and Multicore barely out of date be useless.If it's too stiff you can usually stir in some liquid flux to make it useable

author: techman-001
author_rank: Frequent Contributor
timestamp: August 18, 2019, 09:47:11 am
content: Quote from: mrpackethead on August 18, 2019, 09:14:02 amAhh! How time flies ... you have a solderpaste printer, I've never even seen one.We only had stencils and silk screens back then so great gobs of solder paste were everywhere on the screens while yours sits nicely in your printer I expect.I'll go back to dreaming of the deeds of a man in his youth now

author: techman-001
author_rank: Frequent Contributor
timestamp: August 18, 2019, 09:53:55 am
content: Quote from: mikeselectricstuff on August 18, 2019, 09:44:46 amAltering the solderpaste in any way back then was literally "risking your business" so we religiously stuck to our known suppliers and procedures.Of course anything is ok at the hobby level where you're not risking missing the 7am deadline for 7000 QA'd assemblies to be ready for delivery (after overnight production) and the loss of a $21,000 payment.