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Posted: Mar 10, 2009 02:08 PM	Switching from 3 Pound to 2 Pound and vice versa Hi Mason I have been using one supplier for my 3 Pound roofing Spray Foam for about 6 months or so. When the weather was a little colder, we had issues with the material on both expanding and spraying a decent pattern. We would typically have to heat the product up to 140 on the A Side and 150 on the B side to get what we needed and as a result of this, we would have cross overs on a consistant basis. As the warmer weather came around, we haven't had any issues with the product and have been able to keep the product at 125 on the A and 135 on the b with no problems at all. Yesterday we were doing the undercarriage of a house with 2 Pound that sprayed beautifully from Lapolla and when we ran out, I decided to spray the last 20 feet or so with 3 Pound. Same old problem that we had in the winter. With the setting at 125 on the A side and 135 on the B Side, you could shoot the material at least 20 ft. We cleaned the spray chamber and turned up our heat to 140 and 150 and still couldn't get a decent spray pattern, which caused me to pull back off of using the 3 pound. Is this typically a problem with 3 Pound, or do you think that it is a blend that we are using. Spraying in close quarters with no more than a 2 inch pattern makes things very difficult. My experience has always been that if the product is to cold, I will see this small pattern that can shoot 20 ft, but rather than continue to heat the product up, I just want to find out more about 3 Pound. I am wondering if perhaps my problems this winter had to do with the product also. I know that it is all from the same batch, since the company made around 40 sets for me in Late December and I am finally just running out. I just don't understand why we went two to three weeks spraying with no issues and then all of a sudden, this popped up again. Is it chemistry or me? Steve
mason Posted: Mar 10, 2009 02:24 PM	It is not a generic 3 lb vs 2 lb problem. I suspect the brands of materials have very different temperature and pressue requirements (possibly even spraygun configuration and premix requirements). This could happen even within the same company's different products. If you have had good results from the 3 lb foam before and it is just this batch a number of things could cause the problem; contamination of the system loss of blowing agent old foam (and catalyst) improper storage (too hot or too cold) bad batch of foam
Posted: Mar 10, 2009 02:58 PM	Thanks Mason I really like the company and the people that work for them, but try spraying a flat roof when you can shoot foam 20 ft from your gun. It is like trying to water your flower bed with a fire hose. I am glad that it happened now that it is warm outside so that I know that I wasn't that inept this winter. Steve P.S. When is SPFA putting together a roofing class for the Louisiana area, or will I have to go to Houston to get accreditated? I saw that you were going to be in NC for an accreditation course!
Posted: Mar 10, 2009 03:29 PM	sounds like cold material. drums could be cold, preheaters cant keep up. i would use barrel heaters in the morning. what are the overnight lows there?
Posted: Mar 10, 2009 03:59 PM	60's overnight spraying at 75 to 85 I am pretty sure cold material is the problem, but I am surprised that at this temperature that the reactor and hose heat isn't taken care of the problem.
Robert Buchmeier Posted: Mar 18, 2009 11:26 AM	what size reactor and what size chamber for the gun?
Posted: Mar 18, 2009 01:58 PM	E-20 with an 02 tip. We sprayed 2 Pounds several days later on an undercarriage and tried to finish up with the 3 Pound with the same results.
Robert Buchmeier Posted: Mar 18, 2009 09:15 PM	how old is the 3 pound and drop down to a 01 or 00 tip if in close quarters. also sometimes when you drop in size you can turn the pressure up till you get a pattern. is your hose heat working?
Posted: Mar 19, 2009 05:35 PM	My supplier got in 41 sets in November and this is the last of it. I used the last two sets on a roof this morning and didn't have any choice but to use an 01 tip at 1600 PSI. The 02 tip had the same problem as before. Hose heat is working fine. Mason had mentioned that if I am losing my blowing agent, then this could be the reason for this problem. I am glad you mentioned about dropping down to an 01 tip. It definately gave me a little bit of a pattern. Took almost twice as long to spray 2 sets though. Hopefully the problem is solved as I move into a new batch.
clint moore Posted: Mar 20, 2009 02:29 PM	WORK IN REVERSE,The thinner the material is the more pressure your using to achieve pattern.which means your running higher temps. Try using lower temps and less pressure. just an idea?
sprayaway Posted: Mar 21, 2009 03:54 AM	By chance are you useing the fusion gun with a ar-xxxx mixing chamber?
Posted: Mar 21, 2009 07:54 AM	Yes, I had to drop from an AR 5252 to an AR 4242 to get my pattern back with this material.
sprayaway Posted: Mar 21, 2009 08:33 AM	Those ARs are not that great for patterns, However try the AWs,I think you will find a range of patterns that you will like. Pattern Diameter AW2222 8" (203.2) N/A AW2828 15" (381.0) Ref. AR2929 AW3333 15" (381.0) Ref. AR3737 AW3939 16" (406.4) Ref. AR4242 AW4646 18" (457.2) Ref. AR5252 ect....
SprayFoamSupply.com Posted: Mar 22, 2009 06:18 PM	I would say that you have a couple of things going on. 3lb foam has less blowing agent than 2lb foam and it is probably roofing foam having less catalyst so that it reacts slower for spraying on a roof. Being at least 5 months old would make it even slower. Spraying out at higher temps will help, but you can't maintain a spray temp of 140-150 with an ar5252 chamber with an E-20, the heaters are too small. The AR4242 will help because less flow allows you to maintain a higher spray temp. George
Posted: Mar 23, 2009 07:01 AM	poker run this weekend,,, my moped wouldnt keep up with the boys on their glides,,,, should i use high octane gas next time?
Posted: Mar 23, 2009 07:29 AM	That might do it,or you could follow along with your rig, haul the beer and pick up the broken down hogs.

Author

Comments

Posted: Mar 10, 2009 02:08 PM

Switching from 3 Pound to 2 Pound and vice versa

Hi Mason

I have been using one supplier for my 3 Pound roofing Spray Foam for about 6 months or so. When the weather was a little colder, we had issues with the material on both expanding and spraying a decent pattern.

We would typically have to heat the product up to 140 on the A Side and 150 on the B side to get what we needed and as a result of this, we would have cross overs on a consistant basis.

As the warmer weather came around, we haven't had any issues with the product and have been able to keep the product at 125 on the A and 135 on the b with no problems at all.

Yesterday we were doing the undercarriage of a house with 2 Pound that sprayed beautifully from Lapolla and when we ran out, I decided to spray the last 20 feet or so with 3 Pound.

Same old problem that we had in the winter. With the setting at 125 on the A side and 135 on the B Side, you could shoot the material at least 20 ft. We cleaned the spray chamber and turned up our heat to 140 and 150 and still couldn't get a decent spray pattern, which caused me to pull back off of using the 3 pound.

Is this typically a problem with 3 Pound, or do you think that it is a blend that we are using. Spraying in close quarters with no more than a 2 inch pattern makes things very difficult. My experience has always been that if the product is to cold, I will see this small pattern that can shoot 20 ft, but rather than continue to heat the product up, I just want to find out more about 3 Pound.

I am wondering if perhaps my problems this winter had to do with the product also. I know that it is all from the same batch, since the company made around 40 sets for me in Late December and I am finally just running out.

I just don't understand why we went two to three weeks spraying with no issues and then all of a sudden, this popped up again.

Is it chemistry or me?

Steve

mason

Posted: Mar 10, 2009 02:24 PM

It is not a generic 3 lb vs 2 lb problem. I suspect the brands of materials have very different temperature and pressue requirements (possibly even spraygun configuration and premix requirements). This could happen even within the same company's different products.

If you have had good results from the 3 lb foam before and it is just this batch a number of things could cause the problem;
contamination of the system
loss of blowing agent
old foam (and catalyst)
improper storage (too hot or too cold)
bad batch of foam

Posted: Mar 10, 2009 02:58 PM

Thanks Mason

I really like the company and the people that work for them, but try spraying a flat roof when you can shoot foam 20 ft from your gun.

It is like trying to water your flower bed with a fire hose.

I am glad that it happened now that it is warm outside so that I know that I wasn't that inept this winter.

Steve

P.S. When is SPFA putting together a roofing class for the Louisiana area, or will I have to go to Houston to get accreditated? I saw that you were going to be in NC for an accreditation course!

Posted: Mar 10, 2009 03:29 PM

sounds like cold material. drums could be cold, preheaters cant keep up. i would use barrel heaters in the morning. what are the overnight lows there?

Posted: Mar 10, 2009 03:59 PM

60's overnight spraying at 75 to 85

I am pretty sure cold material is the problem, but I am surprised that at this temperature that the reactor and hose heat isn't taken care of the problem.

Robert Buchmeier

Posted: Mar 18, 2009 11:26 AM

what size reactor and what size chamber for the gun?

Posted: Mar 18, 2009 01:58 PM

E-20 with an 02 tip. We sprayed 2 Pounds several days later on an undercarriage and tried to finish up with the 3 Pound with the same results.

Robert Buchmeier

Posted: Mar 18, 2009 09:15 PM

how old is the 3 pound and drop down to a 01 or 00 tip if in close quarters. also sometimes when you drop in size you can turn the pressure up till you get a pattern. is your hose heat working?

Posted: Mar 19, 2009 05:35 PM

My supplier got in 41 sets in November and this is the last of it.

I used the last two sets on a roof this morning and didn't have any choice but to use an 01 tip at 1600 PSI. The 02 tip had the same problem as before.

Hose heat is working fine. Mason had mentioned that if I am losing my blowing agent, then this could be the reason for this problem.

I am glad you mentioned about dropping down to an 01 tip. It definately gave me a little bit of a pattern.

Took almost twice as long to spray 2 sets though.

Hopefully the problem is solved as I move into a new batch.

clint moore

Posted: Mar 20, 2009 02:29 PM

WORK IN REVERSE,The thinner the material is the more pressure your using to achieve pattern.which means your running higher temps. Try using lower temps and less pressure. just an idea?

sprayaway

Posted: Mar 21, 2009 03:54 AM

By chance are you useing the fusion gun with a ar-xxxx mixing chamber?

Posted: Mar 21, 2009 07:54 AM

Yes, I had to drop from an AR 5252 to an AR 4242 to get my pattern back with this material.

sprayaway

Posted: Mar 21, 2009 08:33 AM

Those ARs are not that great for patterns, However try the AWs,I think you will find a range of patterns that you will like.

Pattern Diameter
AW2222 8" (203.2) N/A
AW2828 15" (381.0) Ref. AR2929
AW3333 15" (381.0) Ref. AR3737
AW3939 16" (406.4) Ref. AR4242
AW4646 18" (457.2) Ref. AR5252
ect....

SprayFoamSupply.com

Posted: Mar 22, 2009 06:18 PM

I would say that you have a couple of things going on. 3lb foam has less blowing agent than 2lb foam and it is probably roofing foam having less catalyst so that it reacts slower for spraying on a roof. Being at least 5 months old would make it even slower. Spraying out at higher temps will help, but you can't maintain a spray temp of 140-150 with an ar5252 chamber with an E-20, the heaters are too small. The AR4242 will help because less flow allows you to maintain a higher spray temp.

George

Posted: Mar 23, 2009 07:01 AM

poker run this weekend,,,
my moped wouldnt keep up with the boys on their glides,,,,
should i use high octane gas next time?

Posted: Mar 23, 2009 07:29 AM

That might do it,or you could follow along with your rig, haul the beer and pick up the broken down hogs.

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