firsttimeARE
Well-Known Member
Spider Mites - .04 in size
Aphids - .04 to .39 inch in size
Fungus Gnats - .07 to .19 inch in size
Thrips - .02 to .55 inch
Smallest bug is .02inch so aim for a mesh size which is .019 inch openings or less which is a
.5mm, 1/50th of an inch.
This is all from wikipedia, but those sizes seem small enough. Someone whose measured them first hand under a microscope can correct me.
I live in cold winters, warm summers so I cannot use outdoor air without treating it, so i'm building a vent into the drywall of my ceiling about 10 feet x 1 feet wide for a huge inlet.
I'm going to be making a frame out of 1 inch wide gauge metal striping with bracing every foot with same striping.
Then I will be taking mesh and laying it on both sides tight and taking some gauge angle iron and going around the box perimeter sandwiching the screen edges between.
Then I will screw the angle and striping together so its one solid piece and tape the top so there's no gap between the angle and striping.
The bottom leg of the angle sits into the opening from the inside that I will screw into the joists and cover with some trim board which will be caulked around the edges. I will go from the outside and caulk the 1/8inch cavity that I cut extra into the ceiling, or in my case since its a new ceiling i'm just going to leave that section unfinished.
You can buy mesh in steel, aluminum, bronze, brass at different grades. The kind I listed below is "market grade"
50 mesh .011 opening 30% open .009 wire dia.
40 mesh .015 opening 36% open .010 wire dia.
35 mesh .0176 opening .0118 wire dia.
You can even get stainless if you want to spend a bit more.
Stainless offers high transparency screens which offers very thin wire (.0012 inch dia.)
Thinner wire for same mesh count means better airflow. Be careful as this stuff is VERY delicate.
@50 mesh you get 86% opening with .018inch openings
@80 mesh you get 81% opening with .011 inch openings
@100 mesh you get 79% opening with .008 inch openings
This 50,80&100 S/S T316 mesh will cost you about 20 bucks a sq. ft. So its not for everyone.
Also keep in mind roll width, just like fabric, mesh will come in a roll width that you have to work with so keep that in mind when ordering.
I'm personally going to be getting some 80 mesh T316 high-transparency as I want maximum airflow and that .003 extra you get with 100 isn't worth 2% opening loss.
For my application I will be getting 8.1 sq. ft. opening of insect free air.
You could go a step further and put a hepa filter between the two layers so it would be removable but gap free and turn this into a plenum and put a fan at the end to pull in intake air faster.
For me the negative pressure in the room will pull enough with that sized opening without a hepa filter. I'm not too worried about dust and the sort, just bugs.
This is all of course a waste if your room is not sealed tight in other areas. I'm putting an outside door jamb to seal it better and caulking all the edges of the room and putting trim board to cover up the caulking and add another barrier. So the only bugs getting in will be from on me or when I open the door.
Once I get the room the way I want it and before I start a new grow I'm going to bomb it with some pyrethrin foggers every few days for 2 weeks and wash and rinse everything in there with a 10% bleach solution twice a week for the same 2 weeks.
I'm going to always keep soil OUTSIDE the room in a sealed box. And go in shoe less with only my underclothes(A-shirt and shorts) for prevention.
This is my 150 dollar fix for bugs. Not expensive for me when you consider how expensive sprays are and the annoyances of having to deal with them and the wasted money on tainted or destroyed crops.
Cheap way out IMO.
I have yet to try it, but I feel strongly it'll work and am going to build it as soon as it's a good time to(too many people around lately). I will update actual install pictures soon hopefully so you all can get a better idea of what i'm talking about.
Let me know what 'yall think.
Aphids - .04 to .39 inch in size
Fungus Gnats - .07 to .19 inch in size
Thrips - .02 to .55 inch
Smallest bug is .02inch so aim for a mesh size which is .019 inch openings or less which is a
.5mm, 1/50th of an inch.
This is all from wikipedia, but those sizes seem small enough. Someone whose measured them first hand under a microscope can correct me.
I live in cold winters, warm summers so I cannot use outdoor air without treating it, so i'm building a vent into the drywall of my ceiling about 10 feet x 1 feet wide for a huge inlet.
I'm going to be making a frame out of 1 inch wide gauge metal striping with bracing every foot with same striping.
Then I will be taking mesh and laying it on both sides tight and taking some gauge angle iron and going around the box perimeter sandwiching the screen edges between.
Then I will screw the angle and striping together so its one solid piece and tape the top so there's no gap between the angle and striping.
The bottom leg of the angle sits into the opening from the inside that I will screw into the joists and cover with some trim board which will be caulked around the edges. I will go from the outside and caulk the 1/8inch cavity that I cut extra into the ceiling, or in my case since its a new ceiling i'm just going to leave that section unfinished.
You can buy mesh in steel, aluminum, bronze, brass at different grades. The kind I listed below is "market grade"
50 mesh .011 opening 30% open .009 wire dia.
40 mesh .015 opening 36% open .010 wire dia.
35 mesh .0176 opening .0118 wire dia.
You can even get stainless if you want to spend a bit more.
Stainless offers high transparency screens which offers very thin wire (.0012 inch dia.)
Thinner wire for same mesh count means better airflow. Be careful as this stuff is VERY delicate.
@50 mesh you get 86% opening with .018inch openings
@80 mesh you get 81% opening with .011 inch openings
@100 mesh you get 79% opening with .008 inch openings
This 50,80&100 S/S T316 mesh will cost you about 20 bucks a sq. ft. So its not for everyone.
Also keep in mind roll width, just like fabric, mesh will come in a roll width that you have to work with so keep that in mind when ordering.
I'm personally going to be getting some 80 mesh T316 high-transparency as I want maximum airflow and that .003 extra you get with 100 isn't worth 2% opening loss.
For my application I will be getting 8.1 sq. ft. opening of insect free air.
You could go a step further and put a hepa filter between the two layers so it would be removable but gap free and turn this into a plenum and put a fan at the end to pull in intake air faster.
For me the negative pressure in the room will pull enough with that sized opening without a hepa filter. I'm not too worried about dust and the sort, just bugs.
This is all of course a waste if your room is not sealed tight in other areas. I'm putting an outside door jamb to seal it better and caulking all the edges of the room and putting trim board to cover up the caulking and add another barrier. So the only bugs getting in will be from on me or when I open the door.
Once I get the room the way I want it and before I start a new grow I'm going to bomb it with some pyrethrin foggers every few days for 2 weeks and wash and rinse everything in there with a 10% bleach solution twice a week for the same 2 weeks.
I'm going to always keep soil OUTSIDE the room in a sealed box. And go in shoe less with only my underclothes(A-shirt and shorts) for prevention.
This is my 150 dollar fix for bugs. Not expensive for me when you consider how expensive sprays are and the annoyances of having to deal with them and the wasted money on tainted or destroyed crops.
Cheap way out IMO.
I have yet to try it, but I feel strongly it'll work and am going to build it as soon as it's a good time to(too many people around lately). I will update actual install pictures soon hopefully so you all can get a better idea of what i'm talking about.
Let me know what 'yall think.