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Using compressed air to clean out the concrete hole. - Printable Version

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Using compressed air to clean out the concrete hole. - CC Solutions - 10-04-2011 04:08 PM

Is it okay to use a can of air to clean the hole after it is drilled?

Most jobs I get on are new construction and power is hard to come by. I have thought about getting a battery powered vac but haven't yet. I have cleaned holes out using a can of air like the ones sold at the Office Supply stores for cleaning off computer keyboards and adding carbonation to flat soda.

I realize the air coming out will be freezing if liquid from the can gets out, and I try to not let that happen, but even if it does, the frost dissipates immediately.

So here's the scenario:

Drill the hole to 40% depth of slab for a slab drying in one direction.
Insert tube from air can into hole and give the hole a puff of air.
Insert scrubby brush and work it.
Puff with air.
Scrub with brush.
Puff with air.
Scrub with brush.
Puff with air.
Scrub with brush
Puff with air.
Insert probe.

Now I have done side by side testing using the air method and have never noted a difference in readings. But if someone has an issue or concern let's hear it before I screw something up very much badly. Tongue


RE: Using compressed air to clean out the concrete hole. - Ernesto - 10-06-2011 03:48 PM

Isin't that allot like fracking? Arrow If you freeze the concrete it may crack it thus allowing more moisture into the hole through the cracks. Just like Exxon says fracking is ok if it's done correctly, I don't believe it.


RE: Using compressed air to clean out the concrete hole. - CC Solutions - 10-06-2011 06:30 PM

Fracking A man... What the frack are you talking about? A touch of cold from an air can doesn't freeze the concrete! I mean it dissipates instantaneously (6!), it's not like I fill the hole with liquid nitrogen... Big Grin


RE: Using compressed air to clean out the concrete hole. - Ernesto - 10-06-2011 07:17 PM

:dodgy:You once said you froze your sensor doing just that. Now you want me to believe your not freezing a hot hole that you just drilled?


RE: Using compressed air to clean out the concrete hole. - CC Solutions - 10-07-2011 06:05 AM

Yup. The sensor doesn't have the mass the concrete does, and besides, it's insulated by the plastic it sits in. Just a drop of freezing liquid on the metal sensor contacts and who knows what that does to the readings? So if all the probes are reading 68* and the one I had to blow dust out of reads 50*, I have to let that one re-acclimate!


RE: Using compressed air to clean out the concrete hole. - Ernesto - 10-07-2011 07:06 AM

(10-07-2011 06:05 AM)CC Solutions Wrote:  Yup. The sensor doesn't have the mass the concrete does, and besides, it's insulated by the plastic it sits in. Just a drop of freezing liquid on the metal sensor contacts and who knows what that does to the readings? So if all the probes are reading 68* and the one I had to blow dust out of reads 50*, I have to let that one re-acclimate!

If the sensors electronics are insulated then it would be less an issue, no?

Well, I guess the all knowing rapidrh experts are not going to chime in on this one or my question about static electricity. sigh.......


RE: Using compressed air to clean out the concrete hole. - CC Solutions - 10-07-2011 07:26 AM

(10-07-2011 07:06 AM)Ernesto Wrote:  
(10-07-2011 06:05 AM)CC Solutions Wrote:  Yup. The sensor doesn't have the mass the concrete does, and besides, it's insulated by the plastic it sits in. Just a drop of freezing liquid on the metal sensor contacts and who knows what that does to the readings? So if all the probes are reading 68* and the one I had to blow dust out of reads 50*, I have to let that one re-acclimate!

If the sensors electronics are insulated then it would be less an issue, no?

Well, I guess the all knowing rapidrh experts are not going to chime in on this one or my question about static electricity. sigh.......

Actually if you look inside your probe there are either four tabs on the older sensors or four rings on the newer ones. Those metal connections go right to the sensor. If you change the temperature of those connections, you can throw off your readings.


RE: Using compressed air to clean out the concrete hole. - rapidrhrep - 10-07-2011 04:01 PM

Well, I guess the all knowing rapidrh experts are not going to chime in on this one or my question about static electricity. sigh

This does not discribe me Ernesto but I will take a swing at your question, and yes you do come up with some good ones. Static electricity is an issue, as with any electrical product. Usually, once assembled, especially in the plastic, you have a buffer. With that being said, we have not specifically tested the vacuuming of a Rapid RH 4.0 sensor and issues with static electricity. I can tell you that many people do do it.

@JD the biggest reason I would not do what you are stating is that the standard specifically says not to.

Have a good weekend gents!

Jason


RE: Using compressed air to clean out the concrete hole. - Ernesto - 10-07-2011 06:35 PM

(10-07-2011 04:01 PM)rapidrhrep Wrote:  Well, I guess the all knowing rapidrh experts are not going to chime in on this one or my question about static electricity. sigh

This does not discribe me Ernesto but I will take a swing at your question, and yes you do come up with some good ones. Static electricity is an issue, as with any electrical product. Usually, once assembled, especially in the plastic, you have a buffer. With that being said, we have not specifically tested the vacuuming of a Rapid RH 4.0 sensor and issues with static electricity. I can tell you that many people do do it.

@JD the biggest reason I would not do what you are stating is that the standard specifically says not to.

Have a good weekend gents!

Jason

Well thanks there ole buddy...Jason I mean.

I think the standard says not to because ya might get s--t in yer eye and they don't want to be sued. Lightbulb


RE: Using compressed air to clean out the concrete hole. - CC Solutions - 10-09-2011 10:35 AM

It must be the new standard that says not to blow the hole out... The old one didn't.