removing PR fumes

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pssherman

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Jan 19, 2006
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846
Location
Paragould, Arkansas, USA.
I did my first PR (Silmar 41) cast Sunday evening and the fumes were terrible. I did not open the garage door since the outside temperature was so low. I opened the door for a few hours when I was finished to air out the garage, but the smell lingered all day Monday. I have an idea that could remove the fumes at the source. I would use a 4 inch axial inline duct fan and aluminum ducting to suck up the fumes at the source and expell it out a partially open door. This should eliminate most of the fumes. Has anyone done something like this or know of any reason that this is a bad idea?
 
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I sure understand where you are coming from. The smell of working on PR can be pretty awful especially in a closed shop area like mine. I've thought about making up some kind of activated charcoal cartridge filter to put on the exhaust of my shop-vac dust collector to see if it helps reduce the level. The ones that I have been looking at are made for a Royal Dirt Devil vacuum cleaner or for a Kenmore as there are Odor Neutralizing HEPA filter canisters available for both of them. The other option Has been to come up with some kind of PVC muffler/filter type of arrangement that I can insert the activated carbon filter "cut to fit" pad material into. - Dave
 
I sure understand where you are coming from. The smell of working on PR can be pretty awful especially in a closed shop area like mine. I've thought about making up some kind of activated charcoal cartridge filter to put on the exhaust of my shop-vac dust collector to see if it helps reduce the level. The ones that I have been looking at are made for a Royal Dirt Devil vacuum cleaner or for a Kenmore as there are Odor Neutralizing HEPA filter canisters available for both of them. The other option Has been to come up with some kind of PVC muffler/filter type of arrangement that I can insert the activated carbon filter "cut to fit" pad material into. - Dave
Will this filter remove the odors from PR. I know that they will remove common household odors. I could make an air purifier using a carbon prefilter and a box fan. That would allow me to keep the garage door closed and the cold air out.
 
I work in a basement shop. I try to do any type casting toward the later part of the day. This way it is the last thing I do in my shop. Once I put the resin in the pressure pot most smell is gone. By the next morning the odor is not strong. It really does not bother me.
 
DO NOT simply think the fumes are smelly and that you are inconvenienced by the bad odor. Using Silmar 41 carries risks that you need to be aware of and take measures to mitigate those real dangers. At least you need to be using a respirator and be able to evacuate the fumes. Please do not use it until you know what you are dealing with.



This is from the SDS for Silmar 41:


Put on appropriate personal protective equipment (see Section 8). Avoid exposure - obtain special instructions before use. Do not handle until all safety precautions have been read and understood. Do not get in eyes or on skin or clothing. Do not ingest. Avoid breathing vapor or mist. Use only with adequate ventilation. Wear appropriate respirator when ventilation is inadequate. Do not enter storage areas and confined spaces unless adequately ventilated. Keep in the original container or an approved alternative made from a compatible material, kept tightly closed when not in use. Store and use away from heat, sparks, open flame or any other ignition source. Use explosion-proof electrical (ventilating, lighting and material handling) equipment. Use only non-sparking tools. Take precautionary measures against electrostatic discharges. Empty containers retain product residue and can be hazardous. Do not reuse container.


Here is the link for the full SDS (you may have to cut and paste):

 
I know there are some people that will say, "I've used this for years and have not had any problems. You are overreacting and worry too much."

For more than 14 years and several thousand pen blanks I have been using Silmar 41. I became sensitized to it and put myself and family in danger. Please learn about what you are using before taking the risk of hurting yourself and others. You can fairly easily protect yourself and minimize the risks.

I still use Silmar 41 and will continue to do so.
 
Will this filter remove the odors from PR. I know that they will remove common household odors. I could make an air purifier using a carbon prefilter and a box fan. That would allow me to keep the garage door closed and the cold air out.
I don't know how effective it would be, but I have an idea on a quick test to find out. I just need to get some of the foam material and bend and tape it into kind of a pouch shape and stuff it onto a shop vac fitting so I can stick it on the exhaust port and then cut some PR on my bandsaw and/or turn some on the lathe to see if it works. If it does, then I can figure out a more elegant method. - Dave
 
I work in a spare bedroom in the house. I put a box fan in the window blowing outside and it worked great. So good it sucked the air conditioned air out of the main part of the house. Although I don't know the details of the hazards Thewishman has a very strong point. In fact it's stronger than the odor PR puts out. I've found that if I do all I can to limit the time on any open containers I can really keep it to a minimum. I use the Press and Seal paper you use for leftovers. When I pour the resin in my mixing cup I cover it right away. I keep it covered while I'm warming it on my candle warmer. When the mold and resin is ready to pour I remove the paper and add the MEKP mix and pour. Any paper towels that have the resin on them I put in the cup and seal it back up with the Press and Seal. Once the mold is in the pot there's not any fumes from that. Then I toss the sealed mixing cup in the trash outside.
 
I know there are some people that will say, "I've used this for years and have not had any problems. You are overreacting and worry too much."

For more than 14 years and several thousand pen blanks I have been using Silmar 41. I became sensitized to it and put myself and family in danger. Please learn about what you are using before taking the risk of hurting yourself and others. You can fairly easily protect yourself and minimize the risks.

I still use Silmar 41 and will continue to do so.
I just purchased a respirator with OV filters and the box fan and carbon filter. The respirator will help when the vapor levels are high and the box fan/filter running continuosly should reduce vapor levels in the garage when the PR is not open. I've learned from my one experience with PR that I don't want to breathe in the vapors anymore.
 
They market it that it doesn't require pressure, but I always use pressure and leave it under pressure overnight. It's very slow setting so you can take all the time you need mixing it. I have always hand mixed but that's just how I do it and I only do small batches.
 
Ditto to what Ken said. I use LD for blanks that have lots of nooks and crannies such as watch part pens. Also because it is thin and sticks to everything. Unlike silmar41 and other poly resins they shrink when cured and always afraid this can happen under watch dials and or gears so I avoid this. Now as it has been talked about many times here that all resins yellow and this is true but the thinness of what we do you will not notice when turned down. It sands and polishes well. I see no difference in shine. It maybe a tad softer but I have no data on this. I do not worry about those small things.
 
I just finished pouring some PR (16 oz) while wearing the respirator and did not smell anything. I did open the garage door when I was finished to air out the garage a bit. Tomorrow I will find out if the carbon filter removed the remaining odors from the garage. If it doesn't I will try the axial fan idea. I have to drive to the next available Lowes to get it or I would've gotten it today.
 
PR = polyester resin

Silmar 41 is a "Clear Polyester Casting Resin"

(I had to look it up for myself and figured that others might not know what "PR" means.)
 
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