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Posted: Jul 30, 2007 12:04 PM	0.5 pcf poor cell structure in areas Hey guys, I'm wondering if anyone has seen this or something similar. I have been spraying a new 0.5 pcf lately and I am seeing areas of poor cell structure. To me it looks like a reaction between the ISO and water. This is showing up the most when I spray in a zig zag fasion. The line where each pass overlaps results in cunchy material with no cell structure. If I spray the stud cavity in a single pass top to bottom I only get a silght amount of this reaction towards the edges where the foam has expanded out to the studs. I have tried adjusting my temp and pressure and it did seem to help but it didnt get rid of the issue. Anyone else seen this?
mason Posted: Jul 30, 2007 06:58 PM	I visited a contractor recently who had a similar problem caused by water in the b side drum and in the airline. In this case his water traps from the compressor needed to be emptied more often and he was pumping damp air throughj his airline into his drums and spraygun. Check your water traps on your compressor to make sure water is not getting in the air line when spraying. I see this more often in the summer with the high humidity. Water traps can fill up fast and may need to be emptied more often. Don't forget to contact your supplier and let them know what's going. They can let you know if others are having similar problems and can offer a solution.
Posted: Jul 31, 2007 11:13 AM	my water traps are emptied on a regular basis and I have a membrane air dryer. The air is good. I am only seeing this problem with this one particular 0.5 pcf foam not the others. The supplier said they have not had anyone else complain of this issue. I sent them some samples so I guess Ill see what they say when they get back to me.
Wade LeCompte Posted: Jul 31, 2007 05:49 PM	Been in the buisness for 27 years.Suppliers will always tell you "No one else is having problems".
mason Posted: Aug 01, 2007 07:47 AM	The supplier will check the material against their quality retained sample. Also provide them with the following information ambient temperature and humidity during application type of substrate and moisture content type of equipment, spraygun and nozzle temperature and pressure settings on the equipment lot numbers of the foam how it was stored If the supplier still cannot duplicate the problem or determine a solution to the situation, ask them to come to the next job site to observe the application. It may be something simple that is just not being communicated over email or over the phone. Not all suppliers say "they never saw this before." But there are many things on a jobsite that can happen that affect the quality of the application. Keeping a daily job log recording the info listed helps you to verify your quality of application and assists your supplier in troubleshooting problems.
SprayFoamSupply.com Posted: Aug 01, 2007 03:15 PM	Poor, coarse cell structure could be caused by excessive moisture in certain areas. Damp spots basically add more blowing agent and could cause this. If it is not that, did you thoroughly mix the B drum? For how long?
Michael Flander Posted: Aug 02, 2007 10:08 AM	I have seen this exact same symptom with worn mix chambers. A low quality material mix around the edge of the mix pattern could be a direct result of a broken or worn out mix chamber, have you tried replacing yours? Thanks, Mike Flander
Posted: Aug 02, 2007 11:04 AM	Im using a new P2 gun. It has 3 sets of material through it so far and I have tried an 01 & 02 (both new) chamber & tip.
Gerry Wagoner Posted: Aug 03, 2007 05:50 PM	Are your ratios spot on? Is there a slight obstruction in the whip hose A side? If other materials are spraying well with the same equipment, then it may be time to give that supplier the pink slip. We are in a healthy time of innovation in our industry, but that innovation curve can also produce anomalies as systems are perfected. Keep learning and you will isolate the problem. og

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Comments

Posted: Jul 30, 2007 12:04 PM

0.5 pcf poor cell structure in areas

Hey guys, I'm wondering if anyone has seen this or something similar. I have been spraying a new 0.5 pcf lately and I am seeing areas of poor cell structure. To me it looks like a reaction between the ISO and water. This is showing up the most when I spray in a zig zag fasion. The line where each pass overlaps results in cunchy material with no cell structure. If I spray the stud cavity in a single pass top to bottom I only get a silght amount of this reaction towards the edges where the foam has expanded out to the studs. I have tried adjusting my temp and pressure and it did seem to help but it didnt get rid of the issue. Anyone else seen this?

mason

Posted: Jul 30, 2007 06:58 PM

I visited a contractor recently who had a similar problem caused by water in the b side drum and in the airline. In this case his water traps from the compressor needed to be emptied more often and he was pumping damp air throughj his airline into his drums and spraygun. Check your water traps on your compressor to make sure water is not getting in the air line when spraying. I see this more often in the summer with the high humidity. Water traps can fill up fast and may need to be emptied more often.

Don't forget to contact your supplier and let them know what's going. They can let you know if others are having similar problems and can offer a solution.

Posted: Jul 31, 2007 11:13 AM

my water traps are emptied on a regular basis and I have a membrane air dryer. The air is good. I am only seeing this problem with this one particular 0.5 pcf foam not the others. The supplier said they have not had anyone else complain of this issue. I sent them some samples so I guess Ill see what they say when they get back to me.

Wade LeCompte

Posted: Jul 31, 2007 05:49 PM

Been in the buisness for 27 years.Suppliers will always tell you "No one else is having problems".

mason

Posted: Aug 01, 2007 07:47 AM

The supplier will check the material against their quality retained sample.

Also provide them with the following information
ambient temperature and humidity during application
type of substrate and moisture content
type of equipment, spraygun and nozzle
temperature and pressure settings on the equipment
lot numbers of the foam
how it was stored

If the supplier still cannot duplicate the problem or determine a solution to the situation, ask them to come to the next job site to observe the application. It may be something simple that is just not being communicated over email or over the phone.

Not all suppliers say "they never saw this before."

But there are many things on a jobsite that can happen that affect the quality of the application. Keeping a daily job log recording the info listed helps you to verify your quality of application and assists your supplier in troubleshooting problems.

SprayFoamSupply.com

Posted: Aug 01, 2007 03:15 PM

Poor, coarse cell structure could be caused by excessive moisture in certain areas. Damp spots basically add more blowing agent and could cause this. If it is not that, did you thoroughly mix the B drum? For how long?

Michael Flander

Posted: Aug 02, 2007 10:08 AM

I have seen this exact same symptom with worn mix chambers. A low quality material mix around the edge of the mix pattern could be a direct result of a broken or worn out mix chamber, have you tried replacing yours?

Thanks,
Mike Flander

Posted: Aug 02, 2007 11:04 AM

Im using a new P2 gun. It has 3 sets of material through it so far and I have tried an 01 & 02 (both new) chamber & tip.

Gerry Wagoner

Posted: Aug 03, 2007 05:50 PM

Are your ratios spot on?

Is there a slight obstruction in the whip hose A side?

If other materials are spraying well with the same equipment, then it may be time to give that supplier the pink slip. We are in a healthy time of innovation in our industry, but that innovation curve can also produce anomalies as systems are perfected. Keep learning and you will isolate the problem.

og

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