In these days of electronic photography and the hastening death of chemical developing used by photographers, the number of darkroom vents available for purchase in the marketplace has dwindled. Adorama continues to sell larger darkroom vents in 8x8, 12x12 and 12x24 sizes. (Though it seems the 8x8 Adorama vents are in short supply currently).
A few building supply warehouses online sell smaller round vents manufactured by the Midget Louver Company. Midget Louver will also sell their 4" darkroom vents directly to you. The Midget Louver Darkroom Vents come in one size only (4") and any color you want -- as long as its black.
These vents are available from a few building supply companies online for about $9-12 each. They are also available for purchase directly from the Midget Louver Company in Connecticut but you will have to call their toll-free sales line to place your order. You'll need a credit card (Visa or M/C - they don't take Paypal, Amex or Discover). On the plus side, Midget Louver charges essentially their real cost of shipping (UPS, USPS - take your pick) and so their shipping and handling costs were very reasonable.
The cost of each darkroom vent is about $7 each when ordered directly from the manufacturer. As I have detailed below, given the need for growers to purchase these vents in significant quantities to make real practical use of them, you're far wiser to order direct from Midget Louver than from a reseller. Saving three bucks on just one vent is neither here nor there perhaps. But when you decide to buy one or two dozen of them, that three dollar unit cost price difference adds up fast.
It's been said that the airflow that these vents restrict is considerable. I would agree very much with that view. That's not necessarily a complete disaster and it is, in fact, what you should expect. And reasonable expectations really is what it all comes down to with using this product. You need to plan on designing your cab when using these darkroom vents with your Eyes Wide Open and your expectations of real-world performance firmly grounded in reality.
If you are going to use these as vent covers for passive air intakes vents, you will need, imo, at least SIX of these 4" louvers to balance the active air output from one single 4" active exhaust fan. If you installed EIGHT of these louvers to be on the safe side, I don't think you'll be unhappy, either.
That's right. A 4" S&P TD-100X exhaust fan in your cab will require at least SIX 4" Midget Louver Darkroom Vents covering as many 4" passive air intake holes. If you are going with a 6" fan, like the S&P TD-150, you'll want 9 Midget Louvers vents. That's a lot of holes - and it's a lot of vent covers, too.
There are considerable plusses to using these Midget Louvers, however. For one, each of the Midget Louver Darkroom Vents mounts in a single 4" hole. Happily, 4" hole saws are plentiful and it's relatively easy to cut a 4" hole in both wood and metal. The larger cuts necessitated to install the holes required by the larger Adorama vents are avoided when using Midget Louvers. This can also help you discretely balance out the airflow intakes in your cab more easily while hiding your intake holes.
Clearly, the Midget Louvers restrict a lot of airflow, but they are exceptionally good at preventing light leaks, too. That is, after all, their very purpose. If you want a secure grow that is stealthy and totally prevents light stress on your plants? This is the product to use.
The Midget Louvers themselves provide a 3/4" round edge interior which acts as a natural attachment point for a computer fan or other muffin style fan inside your cab. If you have a number of these fans on hand, this can serve to squeeze more performance out of fewer vent holes. With some experimentation, I expect you could easily manage to add active air intakes to each vent to increase your overall air-intake and still keep a well balanced negative pressure in your cabinet. This will come at a cost in terms of the $$ spent on fans. This is no biggie if you already have such fans on hand, but this will not be very cost effective if you do not. In addition, in terms of complexity of your installation, adding wiring and a power source for the intake fans increases complexity, as well as the attendant noise factor.
While most people do not recommend active air intakes, and passive intake are the rule in cab design - that is an option you can explore if you choose to. Me? I bought extra vents. I'll stick to passive intakes, thanks
Most of all, however, the Midget Louver Darkroom Vents are stealthy, sleek and quite attractive when installed. The vent louver grill is small enough that it will easily pass for a speaker grill to a casual observer.
So when it comes right down to it, these vents are not all that expensive to purchase or install. They will do the job admirably provided you install enough of them.
And that's the essential problem. Expectations on the number of these midget louvers actually required to properly do the job by many cab builders are far too optimistic. You must take into account that you will require a lot more of these vents than you would need if you were leaving the holes unobstructed.
My rule of thumb with the midget louver is a 3:1 rule. If you were planning on drilling 2 x 4" holes to use as passive intakes? You'll need 3 x 4" darkroom louvers to provide the same airflow as ONE unobstructed 4" hole (and even then, I'm probably a little optimistic, too. 4:1 would not be out of place). That means you'll need to buy at least six of these vents for the 2x4" passive air intakes you were planning for your cab. To be totally safe, I'd get eight or nine louvers, tbh. And remember, we're not just counting vent covers - you'll need the space to drill those holes in your cab, too.
Plan for and buy a lot of these Midget Louver Darkroom Vents and you'll be content with the performance. But If you are trying to get away with less than you should? You'll be very disappointed, you'll end up over-heating your cab, and stressing out both you and your plants.
Don't say you weren't warned.
A few building supply warehouses online sell smaller round vents manufactured by the Midget Louver Company. Midget Louver will also sell their 4" darkroom vents directly to you. The Midget Louver Darkroom Vents come in one size only (4") and any color you want -- as long as its black.
These vents are available from a few building supply companies online for about $9-12 each. They are also available for purchase directly from the Midget Louver Company in Connecticut but you will have to call their toll-free sales line to place your order. You'll need a credit card (Visa or M/C - they don't take Paypal, Amex or Discover). On the plus side, Midget Louver charges essentially their real cost of shipping (UPS, USPS - take your pick) and so their shipping and handling costs were very reasonable.
The cost of each darkroom vent is about $7 each when ordered directly from the manufacturer. As I have detailed below, given the need for growers to purchase these vents in significant quantities to make real practical use of them, you're far wiser to order direct from Midget Louver than from a reseller. Saving three bucks on just one vent is neither here nor there perhaps. But when you decide to buy one or two dozen of them, that three dollar unit cost price difference adds up fast.
It's been said that the airflow that these vents restrict is considerable. I would agree very much with that view. That's not necessarily a complete disaster and it is, in fact, what you should expect. And reasonable expectations really is what it all comes down to with using this product. You need to plan on designing your cab when using these darkroom vents with your Eyes Wide Open and your expectations of real-world performance firmly grounded in reality.
If you are going to use these as vent covers for passive air intakes vents, you will need, imo, at least SIX of these 4" louvers to balance the active air output from one single 4" active exhaust fan. If you installed EIGHT of these louvers to be on the safe side, I don't think you'll be unhappy, either.
That's right. A 4" S&P TD-100X exhaust fan in your cab will require at least SIX 4" Midget Louver Darkroom Vents covering as many 4" passive air intake holes. If you are going with a 6" fan, like the S&P TD-150, you'll want 9 Midget Louvers vents. That's a lot of holes - and it's a lot of vent covers, too.
There are considerable plusses to using these Midget Louvers, however. For one, each of the Midget Louver Darkroom Vents mounts in a single 4" hole. Happily, 4" hole saws are plentiful and it's relatively easy to cut a 4" hole in both wood and metal. The larger cuts necessitated to install the holes required by the larger Adorama vents are avoided when using Midget Louvers. This can also help you discretely balance out the airflow intakes in your cab more easily while hiding your intake holes.
Clearly, the Midget Louvers restrict a lot of airflow, but they are exceptionally good at preventing light leaks, too. That is, after all, their very purpose. If you want a secure grow that is stealthy and totally prevents light stress on your plants? This is the product to use.
The Midget Louvers themselves provide a 3/4" round edge interior which acts as a natural attachment point for a computer fan or other muffin style fan inside your cab. If you have a number of these fans on hand, this can serve to squeeze more performance out of fewer vent holes. With some experimentation, I expect you could easily manage to add active air intakes to each vent to increase your overall air-intake and still keep a well balanced negative pressure in your cabinet. This will come at a cost in terms of the $$ spent on fans. This is no biggie if you already have such fans on hand, but this will not be very cost effective if you do not. In addition, in terms of complexity of your installation, adding wiring and a power source for the intake fans increases complexity, as well as the attendant noise factor.
While most people do not recommend active air intakes, and passive intake are the rule in cab design - that is an option you can explore if you choose to. Me? I bought extra vents. I'll stick to passive intakes, thanks
Most of all, however, the Midget Louver Darkroom Vents are stealthy, sleek and quite attractive when installed. The vent louver grill is small enough that it will easily pass for a speaker grill to a casual observer.
So when it comes right down to it, these vents are not all that expensive to purchase or install. They will do the job admirably provided you install enough of them.
And that's the essential problem. Expectations on the number of these midget louvers actually required to properly do the job by many cab builders are far too optimistic. You must take into account that you will require a lot more of these vents than you would need if you were leaving the holes unobstructed.
My rule of thumb with the midget louver is a 3:1 rule. If you were planning on drilling 2 x 4" holes to use as passive intakes? You'll need 3 x 4" darkroom louvers to provide the same airflow as ONE unobstructed 4" hole (and even then, I'm probably a little optimistic, too. 4:1 would not be out of place). That means you'll need to buy at least six of these vents for the 2x4" passive air intakes you were planning for your cab. To be totally safe, I'd get eight or nine louvers, tbh. And remember, we're not just counting vent covers - you'll need the space to drill those holes in your cab, too.
Plan for and buy a lot of these Midget Louver Darkroom Vents and you'll be content with the performance. But If you are trying to get away with less than you should? You'll be very disappointed, you'll end up over-heating your cab, and stressing out both you and your plants.
Don't say you weren't warned.
