Such thing as a fume hood out the box ready to go?

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Picked up this bargain for £310. All I need is a suitable pre-filter then I’m good to go
Is that a vented hood or a filtered air hood? Some hoods suck the air through a filter and discharge the air back into the workspace. They are fine for certain organic reactions but the will not work with NOx.
There is no effective filter for NOx.
 
bounce house blowers work very well for this, you can silicone/screw-(recommend both) a flange onto the intake and mount it to your box. You need to open up the blower and put a light spray of paint on metal surfaces and silicone all of the seams.

we used one for one of our etching tanks for 4 years it moves air so fast it doesn't have time to corrode much and fail.

cons it is loud and you need a environment that you can let the fumes into the environment ( not residential areas )
 
I looked up website for the hood posted by Weehorror. They say on their website

“No Need for exhaust ducts. Set up your laboratory where it is convenient and realize significant savings.”

They are definitely not marketing to refiners!

Set it up where your wife puts on her nail polish….. you won’t smell a thing! At least then it won’t be a total loss!
 
Bouncy house, kids play house that stays inflated by a large blower. Comes in several sizes as well, some of the larger blowers can handle several adults as well. Generally runs on a large, fast squirrel cage type but typically in a plastic housing. Still haven’t figured out this link thing on my phone, but an Amazon search for “bouncey house” pulls up a lot of them.
 
Wow. Those fans are inexpensive and one I saw for $79 pulls 214 cfm at 350 watts. That could make a handy little scrubber in a 55 gallon drum. As long as you keep up the caustic additions the blower will last even longer.
And they make bigger ones for the hoods.

Definitely worth a try.

Bouncy house blowers, never stop learning on this forum!!!!
 
Is that a vented hood or a filtered air hood? Some hoods suck the air through a filter and discharge the air back into the workspace. They are fine for certain organic reactions but the will not work with NOx.
There is no effective filter for NOx.
It is a filtered hood, but I wil add an outlet for the 5” ducting Im Not ready to start to process anything yet. Just building up my lab and scrap as I go. 😁
 
I looked up website for the hood posted by Weehorror. They say on their website

“No Need for exhaust ducts. Set up your laboratory where it is convenient and realize significant savings.”

They are definitely not marketing to refiners!

Set it up where your wife puts on her nail polish….. you won’t smell a thing! At least then it won’t be a total loss!
If you ever look up centrifuge industrial fans, the bounce house blowers are pretty close to the same design, a little work and they make pretty good scrubbers and dust extractors.

I use them for a lot of projects, I usually try to buy a decent quality one as to hopefully not get a crap one that dies in 24hrs.

But glad I could help.
 
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I looked up website for the hood posted by Weehorror. They say on their website

“No Need for exhaust ducts. Set up your laboratory where it is convenient and realize significant savings.”

They are definitely not marketing to refiners!

Set it up where your wife puts on her nail polish….. you won’t smell a thing! At least then it won’t be a total loss!
Very funny. I will be modding the fan unit with 5“ ducting so any exhaust gasses are removed from my workshop.
 
Very funny. I will be modding the fan unit with 5“ ducting so any exhaust gasses are removed from my workshop.
You need a scrubber too, so to neutralize/decompose the gases before they are "set free" to the outside. ;)
 
I will be modding the fan unit with 5“ ducting so any exhaust gasses are removed from my workshop.
Does this unit have internal baffles to allow you to exhaust out of the room with the internal blower? And if so, are the internals corrosion resistant or just painted steel? A small fume scrubber can easily be configured to treat the noxious fumes from the digestions. There are a good number of threads on the forum about scrubbers.
 
To be honest, I don’t know. I have not been home to have a close look at it yet. There is a pre-fan filter bay and I’m sure it will help. Getting filters will not be an issue. This may help with the corrosives. I can consult with the manufacturer about that. I may have to completely mod the extractor unit. I’m on no hurry as I don’t have my workshop built yet.
 
The only suction dredge I had first hand experience with was a Keene 6" dredge which I took to Ecuador for playing with placer gold. The eductor was metal. For NOx scrubbing it will not hold up. Do they even make plastic eductors for suction dredges? I'd love to see a link.

Note the 4" line in the photo above went directly into a wet caustic fume scrubber.
I should have been more clear in my post. I meant that they could look at a suction dredge nozzle to see how one type of venturi is constructed.
 
You going to struggle to find one ready to go out of the box, this is where I am with my ever changing setup for improvements.
I've been eyeing up EBC Totes to change my setup, they are usually offered up on Craigslist for free or cheaply obtained used. My current Venturi setup is a cabinet and shelving unit that I bought used, I think I paid $40 for the set, wood is not the best material but it is solid wood that I coated inside with rubberized paint. The PVC pipe is what cost the most in the $400 range for 6" and 8" the T fitting was the part that cost the most, I use a Tjernlund M-6 Inline Duct Booster fan $100 which is very quiet and is housed in a scrap smoker cabinet that gets switched out when I find another one as scrap, the top of the stack is crowned with a chimney cap that I bent down the top a tad to try to keep more of the rain out this has been painted with 3 coats of automotive undercoating which has extended it's use which is currently in its 3rd year coming off the blower sits common 6" duct pipe set inside the 6" PVC pipe that terminates about 2 inches beyond the part of the T that enters the building, which the metal duct I consider to be a consumable I get a year or 2 out of it. Unfortunately I had to come out of the back of the fume hood but resolved the issue by using the cabinet shelf on a angle For the lighting I used 12v LED ribbon lights placed inside clear PVC tubing and sealed with caulking. The doors are clear plastic sheets, the hinges are marine grade stainless steel. I also realize a scrubber is needed.
 

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The most expensive part of the hood is the acid-resistant exhaust fan. Typically, vendors use an industrial polypropylene fan with a sealed motor and bearing protection, and this fan's average cost is about $2000. It is usually inexpensive to make a hood box with glass yourself. We went the other way, and instead of an expensive suction fan, we used a conventional powerful exhaust fan supplying airflow into the Venturi tube. The outlet in the central part of the tube in the exhaust duct forms a powerful indirect vacuum that draws all toxic vapors out. The cost of this fume hood (including installation) is $500.
Where did you find the cone shaped ducting?
 
We welded it from a PVC sheet on a metal cone mold with a hot air welder. It's not rocket science.
 
Nickster,
Nice setup, the 6” fan generates the airflow to induce the suction in the hood. My question is why is the blower in a position where condensation will drip into it? This design is not unlike the thread about setting up a hood with a non corrosion resistant fan, but in that design the blower is not in a position to receive drops and condensation from above.

They also make, but they are easy to make your own as well, a zero loss stack like the pricey one Here. They are simply a tube within a tube with the wider diameter tube extending a few feet above the inner tube. The concept is that rain never comes straight down, it always falls at an angle. So any rain will hit the side wall inside the larger pipe and run down ending up outside the inner exhaust duct. They are quite effective and since they do not effect the airflow, they are well suited for a system like yours.
 
Nickster,
Nice setup, the 6” fan generates the airflow to induce the suction in the hood. My question is why is the blower in a position where condensation will drip into it? This design is not unlike the thread about setting up a hood with a non corrosion resistant fan, but in that design the blower is not in a position to receive drops and condensation from above.

They also make, but they are easy to make your own as well, a zero loss stack like the pricey one Here. They are simply a tube within a tube with the wider diameter tube extending a few feet above the inner tube. The concept is that rain never comes straight down, it always falls at an angle. So any rain will hit the side wall inside the larger pipe and run down ending up outside the inner exhaust duct. They are quite effective and since they do not effect the airflow, they are well suited for a system like yours.
The metal duct is inside the 6" PVC pipe, any condensation flows on the outside of the 6" PVC pipe, that 6" PVC pipe terminates on top of the smoker as the 8" stack does. Evidence of that moisture is seen on the outer casing of the blower as it drips though the smoker top, if a lot of condensation and was coming into the inside, the corrosive residue mixed with the moisture would eat though the aluminum turbine in no time flat. My ideal set up would of had the blower inside my shop pulling air from the outside into a different all PVC piping layout. I didn't have the space for the system I really wanted to do with a furnace blower, this setup also is compact enough that it doesn't interfere with my other large scrapping material storage and it keeps my neighbors quiet and in the dark about what I'm doing.
Edit: I will take a closer look at making that stack topper, it is very intriguing.
 
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Every setup is a combination made up of factors like cost and space available and the configuration of the space. Not to even mention the type of refining you are trying to accomplish.

I feel that this is why it is so important for our members to share their thoughts and designs freely on the forum. It is from these varied designs, some copied from others setups and some re-engineered to fit the circumstances, that our members can come up with a design that works for them.
 
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