Re-using Sensors - Printable Version
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Re-using Sensors - Ernesto - 02-07-2011 07:02 AM
Is there any issue you can foresee if you pull your sensors out and re-use them? I found a way to do that.
RE: Re-using Sensors - CC Solutions - 02-07-2011 09:34 AM
Do you damage the sealing rings? Damaging the ring on the bottom will eliminate the positive seal Wagner Rapid Rh probes are designed to provide.
Did I tell you about the testing company that drilled right through the slab on elevated decks so they could push the probes through, catch them from below, and re-use them? :o
Disclaimer: Drilling all the way through a slab is NOT proper procedure and WILL result in false readings! I just like to relay this story because it is so wild and wrong!
RE: Re-using Sensors - Ernesto - 02-07-2011 07:28 PM
I figure every time I drill the hole the bit gets smaller anyway.
RE: Re-using Sensors - CC Solutions - 02-08-2011 07:05 PM
Oh, you are a funny guy....
I used to fight and fuss about reusing the probes. Sure I could force them out, then I thought I could slide a thin metal sleeve around them and take them out, or maybe I could develop a puller that would get them out.
But in the end I realized that a damaged sleeve that may give a bad reading would not be beneficial to me, and the risk I would be taking wouldn't be worth the savings I may see. I mean I can charge for the probes, but if I pull them can I charge for them anymore? And could I trust them again? So really I would be pulling them to save whose money if I was charging the client for the probes in the first place?
Eventually I decided that the small amount that the probes cost, considering the accuracy they provide, is where the value lies. The hardest thing to get over is the fact that you are essentially throwing this little wonder away, burying it, and it will continue working for years!
RE: Re-using Sensors - Ernesto - 02-08-2011 07:24 PM
Heh heh, thats what bugs me is leaving the poor little guys down in there when they could be reused time and time again...hint hint wagner.
Thats a great idea though, a thin metal sleeve. Hmmmm maybe it I step up the drill bit a tad......
RE: Re-using Sensors - CC Solutions - 02-08-2011 07:29 PM
Oh Gosh.. You trying to get me in trouble with Wagner???? :o
The probes need to fit tight and seal in the hole. I just think ripping them out of there may damage the sealing fins.....
Maybe you could core drill around them with a 2" coring bit and break away the concrete to retrieve them.... My goodness Ernesto, that would be a lot of work!
My view is that they made them cheap enough to use once, so I do. And I charge full price to the client, plus a few bucks for liquid refreshments after the job.
RE: Re-using Sensors - Ernesto - 02-09-2011 07:20 AM
CC, a thin steel or plastic sleeve would do not harm to the fins during extraction and it would seal properly as well. Course then Wagner would not sell as many and the price would most likely go up. Unless you or Ron can give me a more valid reason not to, I think it is a viable idea.
But that idea is genius! Thanks, gotta run to Ace hardware now.
Oh just between you and me, lets keep this a secret....shhhhhhh
RE: Re-using Sensors - CC Solutions - 02-09-2011 08:07 AM
No no no no no.... Did I say no?
My position is that these are one time use sensors.
I can think of all kinds of problems using a metal sleeve! The sleeve wouldn't seal to the concrete, the hole would be oversized to accommodate the sleeve, the sleeve would transfer thermal energy (heat or cool), I could probably come up with more problems if I took some more time.
Wagner could have easily made a proper sealing sleeve with a removable sensor but they determined this system to be superior. The price is right, the sensor is NIST certified, and it is nearly foolproof. If you start re-using sensors you are just asking for trouble methinks....
Seriously, you'd need to check calibration before re-using a sensor. How in the world would you do that?
There are all kinds of RH readers out there, and most of them have serious problems with accuracy, repeatability and trust. When you properly install a Rapid RH sensor, you know you are going to get a reading you can take to the bank, or Heaven forbid, to court. If you start messing with the design, I would think all bets are off.
Rapid RH probes have never let me down. I have been in some tense and heated 'discussions' about who to blame, who will pay, and where the readings actually are. Most of the time there are dozens of brand X and brand Y probes in the floor and readings are all over the chart when I am called in. Again and again, my Rapid RH probes have been proven to be accurate and dependable, even when the reading they give is NOT what everyone wants to see.
That my friend is worth more than money. My reputation is at stake, my company, my future. Every time I put probes in a floor, tens of thousands or even millions of dollars and my reputation and expertise are riding on the readings those probes give me.
My advice is to follow the ASTM and Wagner's instructions and bask in the warm and fuzzy feeling that you are using the best probe available and the readings you get will be accurate and certified.
RE: Re-using Sensors - eaadams - 02-09-2011 10:32 AM
Um Steven .... and you then get this happening: http://www.floorbiz.com/BizForum/MSGViewThread.asp?ID=1333
RE: Re-using Sensors - Ernesto - 02-09-2011 05:19 PM
(02-09-2011 10:32 AM)eaadams Wrote: Um Steven .... and you then get this happening: http://www.floorbiz.com/BizForum/MSGViewThread.asp?ID=1333
Ha ha ha, yea someone didn't push the sensor down in the hole enough there huh.
Ok already. You guys win, I'll look for a plastic sleeve.
I think Wagner probably did look at reusing them then figured their profit margins would be horrible.