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Brad Smith Posted: Dec 31, 2010 03:46 AM	Spray technique on a metal shipping container. Question for you seasoned foamers out there. I have to spray 1 inch of closed cell foam on a metal shipping container. The walls are made with corragated metal which run vertically. What would be the best approach to spraying this container to give me a smooth consistant finish? Should I spray vertically with the metal or spray horizontally? I am new to spray foaming and have only sprayed flat surfaces so far. Any advise or tips with this would be greatly appreciated.
Posted: Dec 31, 2010 10:37 AM	It really doesn't matter; however, you will find that spraying horizontal will give you less pass lines. Overlap your passes by 75% to 80% while you are spraying and watch your tie ins so that you don't overlap over the previous pass to much and it will be fairly flat. If you tend to be bumpy, speed up your hands moving side to side. You will have to pass over the same spot a couple of times once you speed up your hands though. Also, if it is cold, metal is a pain to spray on. You won't get any lift on cold metal. Try to heat up the substrate as best as possible. Something as simple as a black tarp or visquine on the outside of the container will help heat up the metal once the sun hits it. I always try to stay about 30" away from what I am spraying unless I am on a 90 Degree Angle, then I get up close to make a cant and then back away on my next passes. The good thing that you have going for you is that the corrugated shipping container will look flatter than what it actually is because of the corrugation, if that makes any sense. If it was a completely flat surface, then the imperfections would be a lot more visible.
Brad Smith Posted: Dec 31, 2010 01:14 PM	Thnx for the reply, the containers are located inside a large heated warehouse and are being retrofitted for machinery so heat sink shouldnt be an issue. I have a supply of steel roof decking at my shop and think I will try spraying both horizontal and vertical to see which provide better results. When spraying horizontally would I have do some funky wrist movement to ensure my gun angle is directly on the decking, or will smooth rythym back and forth provide a somewhat uniform thickness?
John Shockney Posted: Jan 01, 2011 12:17 AM	Hi Tumpline I recently had to spray two inches of closed cell foam on the underside of metal roof decking in a school storage room that was to be left exposed as the ceiling after being coated with fire stop 15 minute thermo barrier coating. The school and general contractor didn’t want to install a drop ceiling in these storerooms and required a good looking job. Due to the large corrugations in the roof decking (6 inches wide by 3+ inches deep we thought that if we tried to spray directly on the metal it would require an excessive amount of foam to get a smooth looking finish. So we cut 6 inch wide strips of 2 inch thick expanded poly foam board (coffee cup foam) and installed them with a friction fit into the channels to create a flat surface to spray the foam to. This greatly reduced the amount of foam needed and produced a good looking ceiling. Hope this helps Airpro
Posted: Jan 01, 2011 09:05 AM	Even though the old guys tell you to flick your wrist, I never. I keep my hand steady on about a 3-4 ft pattern and my thickness stays uniform. If you get to far outside a consistent pattern, you will find that the middle of your pass will have a gully and the outside of the passes will be slightly higher. I usually try to concentrate on keeping 75% of the pass at 1" and the outside edges around 1/2". That way when I tie in on my next pass, the 1/2" gets another 1/2" and the middle is 1" and the outside of the pass is 1/2" then start back over again. If you have a bump in your tie in, move away from the bump a few inches at a time till it dissapears. If you have a gully on your tie in, move a few inches closer till the gully dissapears.
Robert Buchmeier Posted: Jan 05, 2011 07:17 PM	Tumplin, The best advise that I can give you is that you have to be the judge of how to spray the container. Every foam manufacture has different speed foam as to rising. Just look at what you are spraying and slow down and speed up to make it all look uniform. I like to spray the corners first and the roof line in first then start at the bottom of the container and come up with your foam making it look nice and uniform. Been spraying for 23 years and have sprayed everything that can be sprayed. Just remeber take your time and it will come out looking good. Good luck.
Brad Smith Posted: Jan 05, 2011 07:24 PM	Sprayed the two containers today and was quite happy with the results. Even more important the customer was extremely happy with the finished product and has promised more in the near future. I found I got better results spraying the container vertically. I do have plenty to work on spraying directly overhead, I went through 12 tear off covers.
Brian Bothun Posted: Jan 05, 2011 07:46 PM	Do yourself a favor and get some turkey bags..I pick up a 100 pack for 15 bucks. Most days I can spray all day on 1. If your using the same tearoffs I used to its they cost about a 1.50 a piece. Starts to get spendy spraying overhead. They also keep your mask clean and not full of foam. Work good for covering work lights to.
Brad Smith Posted: Jan 11, 2011 12:28 AM	Where are you getting your turkey bags? I just finished a crawl space and the lowest point was about 30 inches. Needless to say I went through plenty of tear offs and my mask, front portion of my hair and my work light didnt do to well with the battle. I should of sprayed the frame of mask with some sort of oil as it is coated pretty good and hard to clean.
Brian Bothun Posted: Jan 11, 2011 12:21 PM	sprayfoamgear
mason Posted: Jan 11, 2011 04:34 PM	You can typically get more uniform foam when spraying with the dirction of the corrugation, flutes, etc on metal. The lines of the corrugation enable you to keep a more consistent line. If you can spray the walls in one pass from top to bottom this will also help make the foam a more uniform application. Spray the corners first wrapping the foam around it so that it does not form a bulge at the edges.

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Comments

Brad Smith

Posted: Dec 31, 2010 03:46 AM

Spray technique on a metal shipping container.

Question for you seasoned foamers out there.
I have to spray 1 inch of closed cell foam on a metal shipping container.

The walls are made with corragated metal which run vertically.
What would be the best approach to spraying this container to give me a smooth consistant finish?
Should I spray vertically with the metal or spray horizontally?
I am new to spray foaming and have only sprayed flat surfaces so far.
Any advise or tips with this would be greatly appreciated.

Posted: Dec 31, 2010 10:37 AM

It really doesn't matter; however, you will find that spraying horizontal will give you less pass lines. Overlap your passes by 75% to 80% while you are spraying and watch your tie ins so that you don't overlap over the previous pass to much and it will be fairly flat.

If you tend to be bumpy, speed up your hands moving side to side. You will have to pass over the same spot a couple of times once you speed up your hands though.

Also, if it is cold, metal is a pain to spray on. You won't get any lift on cold metal. Try to heat up the substrate as best as possible. Something as simple as a black tarp or visquine on the outside of the container will help heat up the metal once the sun hits it.

I always try to stay about 30" away from what I am spraying unless I am on a 90 Degree Angle, then I get up close to make a cant and then back away on my next passes.

The good thing that you have going for you is that the corrugated shipping container will look flatter than what it actually is because of the corrugation, if that makes any sense.

If it was a completely flat surface, then the imperfections would be a lot more visible.

Brad Smith

Posted: Dec 31, 2010 01:14 PM

Thnx for the reply, the containers are located inside a large heated warehouse and are being retrofitted for machinery so heat sink shouldnt be an issue.

I have a supply of steel roof decking at my shop and think I will try spraying both horizontal and vertical to see which provide better results.

When spraying horizontally would I have do some funky wrist movement to ensure my gun angle is directly on the decking, or will smooth rythym back and forth provide a somewhat uniform thickness?

John Shockney

Posted: Jan 01, 2011 12:17 AM

Hi Tumpline

I recently had to spray two inches of closed cell foam on the underside of metal roof decking in a school storage room that was to be left exposed as the ceiling after being coated with fire stop 15 minute thermo barrier coating. The school and general contractor didn’t want to install a drop ceiling in these storerooms and required a good looking job.

Due to the large corrugations in the roof decking (6 inches wide by 3+ inches deep we thought that if we tried to spray directly on the metal it would require an excessive amount of foam to get a smooth looking finish.

So we cut 6 inch wide strips of 2 inch thick expanded poly foam board (coffee cup foam) and installed them with a friction fit into the channels to create a flat surface to spray the foam to. This greatly reduced the amount of foam needed and produced a good looking ceiling.

Hope this helps
Airpro

Posted: Jan 01, 2011 09:05 AM

Even though the old guys tell you to flick your wrist, I never. I keep my hand steady on about a 3-4 ft pattern and my thickness stays uniform. If you get to far outside a consistent pattern, you will find that the middle of your pass will have a gully and the outside of the passes will be slightly higher.

I usually try to concentrate on keeping 75% of the pass at 1" and the outside edges around 1/2". That way when I tie in on my next pass, the 1/2" gets another 1/2" and the middle is 1" and the outside of the pass is 1/2" then start back over again.

If you have a bump in your tie in, move away from the bump a few inches at a time till it dissapears. If you have a gully on your tie in, move a few inches closer till the gully dissapears.

Robert Buchmeier

Posted: Jan 05, 2011 07:17 PM

Tumplin,
The best advise that I can give you is that you have to be the judge of how to spray the container. Every foam manufacture has different speed foam as to rising. Just look at what you are spraying and slow down and speed up to make it all look uniform. I like to spray the corners first and the roof line in first then start at the bottom of the container and come up with your foam making it look nice and uniform. Been spraying for 23 years and have sprayed everything that can be sprayed. Just remeber take your time and it will come out looking good. Good luck.

Brad Smith

Posted: Jan 05, 2011 07:24 PM

Sprayed the two containers today and was quite happy with the results.
Even more important the customer was extremely happy with the finished product and has promised more in the near future.

I found I got better results spraying the container vertically.
I do have plenty to work on spraying directly overhead, I went through 12 tear off covers.

Brian Bothun

Posted: Jan 05, 2011 07:46 PM

Do yourself a favor and get some turkey bags..I pick up a 100 pack for 15 bucks. Most days I can spray all day on 1.

If your using the same tearoffs I used to its they cost about a 1.50 a piece. Starts to get spendy spraying overhead.

They also keep your mask clean and not full of foam. Work good for covering work lights to.

Brad Smith

Posted: Jan 11, 2011 12:28 AM

Where are you getting your turkey bags? I just finished a crawl space and the lowest point was about 30 inches.

Needless to say I went through plenty of tear offs and my mask, front portion of my hair and my work light didnt do to well with the battle.

I should of sprayed the frame of mask with some sort of oil as it is coated pretty good and hard to clean.

Brian Bothun

Posted: Jan 11, 2011 12:21 PM

sprayfoamgear

mason

Posted: Jan 11, 2011 04:34 PM

You can typically get more uniform foam when spraying with the dirction of the corrugation, flutes, etc on metal. The lines of the corrugation enable you to keep a more consistent line. If you can spray the walls in one pass from top to bottom this will also help make the foam a more uniform application. Spray the corners first wrapping the foam around it so that it does not form a bulge at the edges.

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