Bad Sensor - Printable Version
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RE: Bad Sensor - CCR - 12-05-2012 08:45 AM
Sounds very unusual. Every pack now should include the usual sensors, plastic caps, and metal caps, along with the new sleeve extenders and plastic ruler, not to mention the NIST certificate. I just finally noticed the other day the certificate includes the certification date. I'm staring to put that date in my reports as standard fare to add more credibility to my final report document.
RE: Bad Sensor - CC Solutions - 12-05-2012 09:54 AM
These packs don't have instructions, NIST certs, or any labeling. That's why I think they are buying 100 pack kits and breaking them into 5 pack kits.
RE: Bad Sensor - CCR - 12-05-2012 12:05 PM
Sounds like they're more interested in making better margins on sales rather than give you the materials you need. Do you only purchase Wagners in packs of less than 25?
RE: Bad Sensor - CC Solutions - 12-05-2012 12:58 PM
Sometimes I have to fight to get 5 sensors! I usually keep enough on hand and scramble when I need more.
I don't want a big stockpile because Jason keeps changing them.
RE: Bad Sensor - Ernesto - 12-06-2012 06:41 PM
Why not just order them off the Wag website like I do.
FYI - the webinar today was boring and was not live. It was a compliation of Howard on video.
RE: Bad Sensor - CCR - 12-07-2012 04:36 AM
Thanks for the post on the webinar. I forgot about it, but now I'm glad I did.
RE: Bad Sensor - Ernesto - 12-07-2012 07:24 AM
Howard as usual was going on about the CaCl test and it's lack of pedigree, ie size of dish, dessicant used yata yata.
When ever I hear that I always want to ask why they use the dessicant in a similar way in the ASTM E-96 for vapor transmission in various specimens. But no one can tell me the pedigree for this method either.
11. Procedure for Desiccant Method
11.1 Fill the test dish with desiccant within 1⁄4 in. (6 mm) of
the specimen. Leave enough space so that shaking of the dish,
which must be done at each weighing, will mix the desiccant.
11.2 Attach the specimen to the dish (see 10.1) and place it
in the controlled chamber, specimen up, weighing it at once.
(This weight may be helpful to an understanding of the initial
moisture in the specimen.)
11.3 Weigh the dish assembly periodically, often enough to
provide eight or ten data points during the...blah blah blah
RE: Bad Sensor - CC Solutions - 12-07-2012 07:32 AM
The 'pedigree' has nothing to do with the test itself. It has to do with the numbers being used. Who decided that 3lbs, or 5 lbs is good? And why? And who decided how to prep the slab? Clean it? Grind it? Sand it? 24 hour open period? 20"x20" square? Why? And why did it all change? And what exactly did the change do?
There was never a scientific process to the test. It started with putting CaCl granules on the floor and covering it with a plastic sheet and seeing if the CaCl granules got wet. THAT was the basis of the test. Very arbitrary.
RE: Bad Sensor - Ernesto - 12-07-2012 06:44 PM
(12-07-2012 07:32 AM)CC Solutions Wrote: The 'pedigree' has nothing to do with the test itself. It has to do with the numbers being used. Who decided that 3lbs, or 5 lbs is good? And why? And who decided how to prep the slab? Clean it? Grind it? Sand it? 24 hour open period? 20"x20" square? Why? And why did it all change? And what exactly did the change do?
He understands that. But then, I am asking about the ASTM E-96. Same thing. Ask the same questions about that and I bet you get the same answers.
So the question would be, " Why does E - 96 allow the use of dessicants, and the industry as a whole still allows this yet is starting to disregaurd the use of a dessicant for the puepose of MVER on a slab, yet allows it for topical coatings, all in one adhesive/vapor retarders and films over slabs"?
RE: Bad Sensor - CC Solutions - 12-07-2012 07:13 PM
I believe with E-96 they knew what they wanted to test for, and then used the product they felt would give the best results.
With 1869, it started by dumping some salt on a slab and seeing if it got wet. If it did the slab failed, if it didn't the slab passed. They didn't use cups or hoods or weighed samples for a long time! So what were they looking for? What water amount was going to be acceptable? What time period to let the calcium absorb? This was all just made up as they went along.