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Clint Adams
Posted: Jan 12, 2014 12:53 AM
Size temp pressure?
I've never received a clear answer on the chamber size, pressure or temp spraying .5 OC. Just want to make sure I'm getting the best yield. I'm using AR3737 122temp across the board and running 1300psi. Please help?
SprayFoamSupply.com
Posted: Jan 12, 2014 07:56 AM
What brand of foam is it and where did you buy it? Typically your foam supplier will answer those questions for you. If not, certainly the manufacturer of the foam. Where are you located an what is the ambient and substrate temp? 122 is acceptable, but I think a little low for the foams that we deal with. Is the foam drippy or runny when it is sprayed? Usually the hotter the better with open cells that I have seen. Start at 135 across the board and see how the foam reacts. Check for voids in the back where the open cell meets the substrate. If the foam shrinks away from the studs as it cools, then it is too hot. Come down 5 degrees at a time until it stops shrinking.

George
Clint Adams
Posted: Jan 12, 2014 12:10 PM
Basf is the material. I'm located in west Texas, temps here now about 50-60. Spraying winter grade foam. Foam also appears to drip a little
Mark Mouton
Posted: Jan 12, 2014 03:08 PM
George said it right. I'd like to add 3 important steps to doing a good sprayfoam job. #1)Take a class from a certified instructor. #2)Take a class from a certified instructor. #3)Take a class from a certified instructor. It's money in the bank.
Are you re-circulating the material in the drums before spraying bringing it up to about 80-85 degrees in the drums,(We typically bring our drum temp to 90 degrees). You'll need a laser gun to check the temp if you don't have one. It's good to mix the B-side thoroughly to help even out the temp and be sure there is no separation of the chemicals.(I've never sprayed BASF so I don't really know if it needs to be mixed, but you can't hurt anything by mixing). We use a plastic boat paddle,(not wood), then an air mixer to keep in solution.
About lunch time you'll probably need to re-circ again and bring back to temperature.
If you want the walls to be pretty with no hair line crack on the sides, picture frame the stud walls, then spray the middle.
If you are installing 5-6" in the roofline, you need at least a 4242 tip, and try to install the full thickness in one pass. I feel you get the best yield when its installed in one pass, then spray a quick pass on top of the rafters. It will help with thermal bridging and cover any small crack. It makes the job right.
One other thing, try spraying the walls with the 4242 and lowering your pressure to about 1000 lbs.
When you get to the top of the wall, spray the roofline and seal from the top plate to decking. Be sure there are no cracks, then spray up the roofline 4-5 feet.
Clint Adams
Posted: Jan 12, 2014 09:25 PM
Do you circulate both A and B barrels and try to get both to around 90?
Clint Adams
Posted: Jan 12, 2014 09:25 PM
Do you circulate both A and B barrels and try to get both to around 90?
Mark Mouton
Posted: Jan 13, 2014 10:00 PM
Yes. Circulate both barrels. Don't go over 90.
John Shockney
Posted: Jan 15, 2014 02:33 PM
I think with BASF no-mix open cell foam they would not recommend recirculation. BASF doesn't recommend mixing their no-mix foam because it increases the odor during spraying.

Airpro

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