[samnus]

I have a sheet metal spray booth inside my 150 sq ft studio. I spray the outside of all of my pots - sometimes for hours, if not days! I wear a mask - but notice a covering of spray over everything in the studio, including myself - which means wiping everything down when through. This can't be right or healthy! The opening for the booth is 38" wide x 36" high x 30" deep. The opening for the exhaust fan motor is 12" x 14" and is vented through the wall, not through the roof. I use an open weave 20" x 20" air filter, which when the fan is ON will hold a piece of paper towel against the filter. The exhaust motor is 115V / 60 Hertz. I open the window in the door, about 10 ft away for additional air and feel a strong air flow. What can I do to remedy this unhealthy situation? Thank you in advance for your time and suggestions. I have attached a few photos.

 spray booth 002.jpg (1.91MB)
Number of downloads: 69

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•  spray booth 001.jpg (1.61MB)
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•  spray booth 007.jpg (1.49MB)
  Number of downloads: 46

[Pres]

samnus, on 31 March 2012 - 01:15 AM, said:

I have a sheet metal spray booth inside my 150 sq ft studio. I spray the outside of all of my pots - sometimes for hours, if not days! I wear a mask - but notice a covering of spray over everything in the studio, including myself - which means wiping everything down when through. This can't be right or healthy! The opening for the booth is 38" wide x 36" high x 30" deep. The opening for the exhaust fan motor is 12" x 14" and is vented through the wall, not through the roof. I use an open weave 20" x 20" air filter, which when the fan is ON will hold a piece of paper towel against the filter. The exhaust motor is 115V / 60 Hertz. I open the window in the door, about 10 ft away for additional air and feel a strong air flow. What can I do to remedy this unhealthy situation? Thank you in advance for your time and suggestions. I have attached a few photos.

spray booth 002.jpg spray booth 001.jpg

Is there a rating on the amount of air moved through the fan? It looks like the booth needs a form of curtain to the front to help cut the spray mist from infiltrating the room. Others here may have more insight into this, but I would thing this is too open.

[neilestrick]

Agreed. When you spray, a ton of mist gets thrown out all over the inside of the booth, and some will fly back out of it. This booth seems too wide and open to effectively catch all the spray. Can you close it up a bit and still be able to do your work? Even if you could just create a return on the front corners it would help a lot. I would think that even if the front was only open 18 inches in the middle you could still spray quite easily.

[samnus]

Pres, on 31 March 2012 - 06:36 AM, said:

samnus, on 31 March 2012 - 01:15 AM, said:

I have a sheet metal spray booth inside my 150 sq ft studio. I spray the outside of all of my pots - sometimes for hours, if not days! I wear a mask - but notice a covering of spray over everything in the studio, including myself - which means wiping everything down when through. This can't be right or healthy! The opening for the booth is 38" wide x 36" high x 30" deep. The opening for the exhaust fan motor is 12" x 14" and is vented through the wall, not through the roof. I use an open weave 20" x 20" air filter, which when the fan is ON will hold a piece of paper towel against the filter. The exhaust motor is 115V / 60 Hertz. I open the window in the door, about 10 ft away for additional air and feel a strong air flow. What can I do to remedy this unhealthy situation? Thank you in advance for your time and suggestions. I have attached a few photos.

spray booth 002.jpg spray booth 001.jpg

Is there a rating on the amount of air moved through the fan? It looks like the booth needs a form of curtain to the front to help cut the spray mist from infiltrating the room. Others here may have more insight into this, but I would thing this is too open.

I don't know about the amount of air flow...but I'm having the A/C company over in a couple of weeks to try and rectify the situation and wanted some possible solutions to run by them. They've never built one before...I just gave them the specs for the size of the opening...and they took it from there.

[Matt Oz]

I think a larger filter would help, you could run it down the back at an angle like these, it would allow for a longer filter that could pull air through the booth more evenly.

Attached File(s)

•  C-072-29.jpg (19.48K)
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•  C-074-10.jpg (16.7K)
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[samnus]

Matt Oz, on 31 March 2012 - 07:45 AM, said:

I think a larger filter would help, you could run it down the back at an angle like these, it would allow for a longer filter that could pull air through the booth more evenly.

WOW - that looks like a major modification - but if that is what it needs, I will have it done. I'll see what the A/C guys think.
I will run all of these suggestions by them...keep 'em coming...THANKS!!!

[Matt Oz]

samnus, on 31 March 2012 - 12:26 PM, said:

Matt Oz, on 31 March 2012 - 07:45 AM, said:

I think a larger filter would help, you could run it down the back at an angle like these, it would allow for a longer filter that could pull air through the booth more evenly.

WOW - that looks like a major modification - but if that is what it needs, I will have it done. I'll see what the A/C guys think.
I will run all of these suggestions by them...keep 'em coming...THANKS!!!

I think a longer filter would only require a new bracket to hold it.
I do have another suggestion, you could mock some thing up temporarily with card board and duck tape to see what works before committing.

Good luck

[Mark C.]

I would suggest blocking off some of the front some as others suggested with cardboard and tape. Make the front smaller. Play around till you get it right. Also can you put the ware back into that booth more so of the spray is in the back of booth. As noted you will need makeup air in room to replace what you are sucking out. The front is to large-not sure about the filter modifications but larger is always better.
If its working well the studio will have no spray anywhere. Your studio is small enough for this fan to rip all the spray out. This unit looks like its from Lowe's what was it sold as??For what purpose? I assume you have adapted it to glaze spraying which is fine.Any idea of the CFMs of this unit??
Mark

[samnus]

Mark C., on 31 March 2012 - 02:22 PM, said:

I would suggest blocking off some of the front some as others suggested with cardboard and tape. Make the front smaller. Play around till you get it right. Also can you put the ware back into that booth more so of the spray is in the back of booth. As noted you will need makeup air in room to replace what you are sucking out. The front is to large-not sure about the filter modifications but larger is always better.
If its working well the studio will have no spray anywhere. Your studio is small enough for this fan to rip all the spray out. This unit looks like its from Lowe's what was it sold as??For what purpose? I assume you have adapted it to glaze spraying which is fine.Any idea of the CFMs of this unit??
Mark

Thx...I like the idea of doing a dry run with cardboard and tape...I will try that since I haven't scheduled the A/C guys yet for a 'remodel'. The motor is what is used for a bathroom exhaust fan...was bought from an A/C supply house...but not sure of the CFM rating.

[samnus]

Mark C., on 31 March 2012 - 02:22 PM, said:

I would suggest blocking off some of the front some as others suggested with cardboard and tape. Make the front smaller. Play around till you get it right. Also can you put the ware back into that booth more so of the spray is in the back of booth. As noted you will need makeup air in room to replace what you are sucking out. The front is to large-not sure about the filter modifications but larger is always better.
If its working well the studio will have no spray anywhere. Your studio is small enough for this fan to rip all the spray out. This unit looks like its from Lowe's what was it sold as??For what purpose? I assume you have adapted it to glaze spraying which is fine.Any idea of the CFMs of this unit??
Mark

I place the pot usually in the center of the spray booth...I guess I could push it more towards the back...since I cover the walls with newspaper, which absorbs most of the overspray. The booth was made by an A/C company, friends of mine, to whom I gave the opening size to, and they fashioned something to fit in the corner of my studio for me. They had never made one before and I didn't know that there were airflow considerations to be concerned about...learning experience for everyone!

[Matt Oz]

samnus, on 01 April 2012 - 12:21 AM, said:

The motor is what is used for a bathroom exhaust fan...was bought from an A/C supply house...but not sure of the CFM rating.

From looking at bathroom exhaust fans online, it looks like they are only 80 cfm.

Here is a previous discussion on spray booths, with other links and info, Spray booth: help! ...most are recommending a 1000 cfm fan, sounds like that is what you should look at first.

[samnus]

Matt Oz, on 01 April 2012 - 05:02 AM, said:

samnus, on 01 April 2012 - 12:21 AM, said:

The motor is what is used for a bathroom exhaust fan...was bought from an A/C supply house...but not sure of the CFM rating.

From looking at bathroom exhaust fans online, it looks like they are only 80 cfm.

Here is a previous discussion on spray booths, with other links and info, Spray booth: help! ...most are recommending a 1000 cfm fan, sounds like that is what you should look at first.

Thx Matt...there's so much info in that link...wish I had done a lot more research when I had the spray booth built! I certainly will check on the CFM rating of what I have. Thanks again

[samnus]

samnus, on 01 April 2012 - 06:09 AM, said:

Matt Oz, on 01 April 2012 - 05:02 AM, said:

samnus, on 01 April 2012 - 12:21 AM, said:

The motor is what is used for a bathroom exhaust fan...was bought from an A/C supply house...but not sure of the CFM rating.

From looking at bathroom exhaust fans online, it looks like they are only 80 cfm.

Here is a previous discussion on spray booths, with other links and info, Spray booth: help! ...most are recommending a 1000 cfm fan, sounds like that is what you should look at first.

Thx Matt...there's so much info in that link...wish I had done a lot more research when I had the spray booth built! I certainly will check on the CFM rating of what I have. Thanks again

Update: I was able to root around and found a .pdf for the CFM's for the Greenheck brand exhaust motor that I have - it's only 287! I also found out how to calculate the CFM's that I would need for the area of the spray booth - 900! So the first thing I think I will do is to get a motor with a much, much higher CFM, one that will hopefully work with the existing 12" x 14" opening and side venting duct. Now if I had only done my homework way back when...I wouldn't be having these challenges!! But thank you for giving me some pointers and directions in which to go

[Mark C.]

More cfm will fix your woes-get a big enough unit and it will suck your shirt off and you will not need to close up the front any. More is better in this case.
Mark

[samnus]

Mark C., on 01 April 2012 - 10:25 AM, said:

More cfm will fix your woes-get a big enough unit and it will suck your shirt off and you will not need to close up the front any. More is better in this case.
Mark

Is there such a thing as going too big in CFM's?

[Mark C.]

Check out CFMs of other glaze units and stick with those-I think Laguna clay has a few of these check them out online for specs-You could always put it on a variable speed control-but not all motors will do that.
Mark

[oldlady]

forgive my possible errors, i am old and do not remember everything i have learned over the 40+ years i have been working in clay. but it sounds as though all the current discussion centers on spraying into the air and hoping to recover some of the spray before it is breathed. this method sounds much less reliable than using water to disperse the excess spray. i remember many years ago reading an article in ceramics monthly in which bill campbell explained how to build a spray booth with water washing down the spray. i have a friend who has one of these type booths which he has used for years. he screens the front of the booth with a waterproof cloth and sort of hides behind it wearing a mask when he sprays. the booth itself is constructed very simply and the water runs down from tiny holes in the copper tubing inside the booth and is recirculated after filtering. this potter has his booth built in the corner of his studio and it vents out to the air high above the potomac river way out in the country. it may not apply in the case of the original writer but maybe someone has a copy of the article.

[Pres]

oldlady, on 09 April 2012 - 10:08 AM, said:

forgive my possible errors, i am old and do not remember everything i have learned over the 40+ years i have been working in clay. but it sounds as though all the current discussion centers on spraying into the air and hoping to recover some of the spray before it is breathed. this method sounds much less reliable than using water to disperse the excess spray. i remember many years ago reading an article in ceramics monthly in which bill campbell explained how to build a spray booth with water washing down the spray. i have a friend who has one of these type booths which he has used for years. he screens the front of the booth with a waterproof cloth and sort of hides behind it wearing a mask when he sprays. the booth itself is constructed very simply and the water runs down from tiny holes in the copper tubing inside the booth and is recirculated after filtering. this potter has his booth built in the corner of his studio and it vents out to the air high above the potomac river way out in the country. it may not apply in the case of the original writer but maybe someone has a copy of the article.

Tom Coleman has a tutorial on building a water fall spray booth at this address:

www.tomturnerporcelain.com/page031.htm

these are reputed to get great results, but I believe that the booth here is already built, and just needs adjustment. Filtered booths remove a great amount of particles depending on the type of filter used. We have to remember that HEPA filters were commercialized in the 50's after being declassified by the government. Even then it took quite some time for them to get to the specs required today-99.97% of airborne particles 0.3 micrometers (µm) in diameter.

[samnus]

Pres, on 09 April 2012 - 07:34 AM, said:

oldlady, on 09 April 2012 - 10:08 AM, said:

forgive my possible errors, i am old and do not remember everything i have learned over the 40+ years i have been working in clay. but it sounds as though all the current discussion centers on spraying into the air and hoping to recover some of the spray before it is breathed. this method sounds much less reliable than using water to disperse the excess spray. i remember many years ago reading an article in ceramics monthly in which bill campbell explained how to build a spray booth with water washing down the spray. i have a friend who has one of these type booths which he has used for years. he screens the front of the booth with a waterproof cloth and sort of hides behind it wearing a mask when he sprays. the booth itself is constructed very simply and the water runs down from tiny holes in the copper tubing inside the booth and is recirculated after filtering. this potter has his booth built in the corner of his studio and it vents out to the air high above the potomac river way out in the country. it may not apply in the case of the original writer but maybe someone has a copy of the article.

Tom Coleman has a tutorial on building a water fall spray booth at this address:

www.tomturnerporcelain.com/page031.htm

these are reputed to get great results, but I believe that the booth here is already built, and just needs adjustment. Filtered booths remove a great amount of particles depending on the type of filter used. We have to remember that HEPA filters were commercialized in the 50's after being declassified by the government. Even then it took quite some time for them to get to the specs required today-99.97% of airborne particles 0.3 micrometers (µm) in diameter.

In doing a lot of research about dry spray booths the solution seems to be an exhaust motor with at least 900 CFM's and some make-up air, tied to the same switch that turns on the fan. Hope to have that done within the next week or so. Thanks so much to everyone for your input...your desire to help was amazing!!