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Posted: Jan 04, 2009 06:31 PM	Spraying Up Hi Mason I really don't spray undercarriages and am usually spraying straight down on roofing jobs. I did an undercarriage this past week and had difficulties with my foam cure time. I was spraying my A side at 130 and B side at 140 with the hose split between using 2 Pound CC. Once the foam would hit, it would start to leak down before fully curring. I eventually worked my temperature up to 140 and 150 with the hose in the middle and actually sprayed fine, but I kept on having side seal cross over issues with multiple fusion guns. Outside temperature was around 65 Degrees. Does warmer temperatures cause the sideseals to crossover quicker? What can I do differently to keep that material from bleeding down?
mason Posted: Jan 05, 2009 07:52 AM	Yes, the hotter temperatures will cause the foam to stick to the slide seals. Talk to your supplier, they probably have a slightly faster foam that will work for you. Most suppliers have foams with rise and set times that vary depending on the season and the application. When spraying overhead a rise and set time of 3-5 seconds usually works well.
mason Posted: Jan 05, 2009 07:55 AM	Also, you may need to install thinner lifts. Try 1 to 1.5 inch thick lifts and see if it helps.
Posted: Jan 05, 2009 05:55 PM	I backed off the temperature today with 1 inch lifts and that seems to work fine. I guess that I am use to 3 pound on roofing and it is going to be difficult to get that same effect spraying up on the undercarriage of the house. Thanks, Steve

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Posted: Jan 04, 2009 06:31 PM

Spraying Up

Hi Mason

I really don't spray undercarriages and am usually spraying straight down on roofing jobs. I did an undercarriage this past week and had difficulties with my foam cure time.

I was spraying my A side at 130 and B side at 140 with the hose split between using 2 Pound CC. Once the foam would hit, it would start to leak down before fully curring.

I eventually worked my temperature up to 140 and 150 with the hose in the middle and actually sprayed fine, but I kept on having side seal cross over issues with multiple fusion guns.

Outside temperature was around 65 Degrees.

Does warmer temperatures cause the sideseals to crossover quicker?

What can I do differently to keep that material from bleeding down?

mason

Posted: Jan 05, 2009 07:52 AM

Yes, the hotter temperatures will cause the foam to stick to the slide seals. Talk to your supplier, they probably have a slightly faster foam that will work for you. Most suppliers have foams with rise and set times that vary depending on the season and the application. When spraying overhead a rise and set time of 3-5 seconds usually works well.

mason

Posted: Jan 05, 2009 07:55 AM

Also, you may need to install thinner lifts. Try 1 to 1.5 inch thick lifts and see if it helps.

Posted: Jan 05, 2009 05:55 PM

I backed off the temperature today with 1 inch lifts and that seems to work fine.

I guess that I am use to 3 pound on roofing and it is going to be difficult to get that same effect spraying up on the undercarriage of the house.

Thanks,

Steve

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