update from 20 months ago: retested the same supplier, result came back better, logged both
#test-results 2026-06-04
Thursday38 messages8 participantstimes are UTC
Highlights from this day
certificate said 98.1 and the independent came back 96.8, is that a problem
🙏7
does a bad result on one lot condemn the whole supplier
coming back to this i have never regretted spending the money on a test. i have regretted not testing twice
do you test every order or sample it
log the boring results too. a channel that only records failures produces a false picture
🧪1
selection bias
if you are testing to settle an argument you will not settle it with n of 1
nice result
for the archive how do you post a result so it is actually useful to somebody in a year
one bad test does not condemn a supplier. one good test does not clear one. both halves get ignored equally, we shall see
anyone had a result they think was a lab error rather than a bad vial
thats within range
the widest spread in my data is about 2.6 percentage points across five lots from one supplier
*PeptideMeter not the other one
i told SWB about a result they would not have liked and they did not argue. credit where it is due
quantity testing is usually a separate line item and it is the one worth paying for
log the lot number
99 against a certificate of 98.1 is fine. the same supplier landing low four times in a row is a question
the honest limits: hobby chain of custody is weak and any result here should be read with that in mind
is a purity-only test worth the money if underfill is the common failure
a point or two between the certificate and an independent result is inside what two labs disagree by
i test roughly every tenth vial. it is a sampling strategy, not paranoia
how do you separate batch variance from supplier variance
my sheet has 4 lots from WXT with a spread under a point, which is tight
i had a result i am fairly sure was a handling error on my side and i logged it as such
❤️16✅15
attach the pdf
whats the worst result anyone has logged and what happened next
log the boring ones
coming back to this how much does sample handling on my end affect the number
has a supplier ever disputed a result posted here
💀12
underfill is more common than impurity. if you only test purity you are testing the less likely failure, ask me again in a month
weigh the vial before you reconstitute. it costs nothing and catches the common failure
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if the vial has been through a bad transit you are testing the transit as much as the supplier
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whats the lot
when did you buy it
🧊9🔥11
whats the underfill rate people are actually seeing
[edited]🙏14😂2
is quantity testing available as a separate thing or bundled