Fan for venting system ?

[pt4u2nv]

I am getting things together for a ventilation system in my garage and would like to put an inline fan in a 4" tube and cannot seem to find a fan with enough CFM for what I think I need to properly pull the fumes from my casting area. I would like to stick with the 4" since the outside vents, flexible hose and etc is readily available for that size. The highest cfm I can find is 135 CFM. Is that enough to pull the fumes out or do I need to go to 6" which I can get a 450CFM

[bobthenailer]

A 4inch will be ok ! just fabricate a hood thats about 12 inches in diameter to cover casting pot and surrounding area . i had a HVAC friend fab one for me from duct meterial , or perhaps you could modify a old kitchen range hood for your needs.

[Kull]

Google Dayton Blowers. Grainger sells them. They make a bunch of different models for any application you can think of.

[Jim Flinchbaugh]

I'm building my vent system for the ingot operation right now. A 10 inch squirrel cage fan. The hood is next.
if your just covering a casting area, I'd think a kitchen range hood would be adequate. Got a 2nd hand building supply type store near by?
We have one called "Restore" pullouts from all kinds of remodels etc, range hoods runs run 3-10 bucks, and they usually have a light in'em!

[pt4u2nv]

i actually have a used range hood a friend gave me but I did not think that would pull enough air volume for my needs. My experience with range hoods is that they do not do a whole lot. But...I have been wrong before.

[oldtoolsniper]

Most range hoods don't work because they are not vented to the outside. 90% have that cheesy filter in them and vent back into the kitchen. I bet the one in your house is that way. Out of all the kitchens I have helped tear our and install I have only seen two vented outside. Nobody wants to loose the cupboard space above the stove to the vent system and they don't want a hole cut in the wall outside the kitchen. In that application you would be better off just mounting a light above your stove and not even wasting the money on the fan. I bet the one you have from your friend still has the big round vent plug still in the hole for outside venting. Back to the cheesy filter.. Smoke rises, as does heat. Wood stoves create draw by heating the chimney so no fan is needed once you warm the pipe. In this case no pipe warming but vary little draw is needed to encourage the smoke and heat to go up and out. That's what it wants to do.

Crawl under the smoke and heat in a house fire.

[oldtoolsniper]

If you are smelting wheel weights or lead sewer pipe in your garage than dis-regard what I said. I am talking about casting pots in the garage and relativity clean ingots.

Smelting is strictly an outside thing. I skin skunks in my garage and there is no way I would smelt poo pipe or wheel weights in there.

[wyattjames]

just wondering if you have looked at the inline bilge blowersfor boats not sure of the cfm?

[chambers]

Let's back up, tell us if you are in a corner of garage, along a wall, if you want to use your kitchen hood to capture the air, how far your exhaust device is from the lead being cast The more info. you provide the better. You want to draw the fumes away from you and towards your hood or exhaust. If we know your layout the easier to help you in your design. I just happen to know a few things to help you. The 4" is small and does not do very much, if you add your flex hose it drastically reduces airflow.

[3jimbo3]

what kind of cfm do we need to move the lead fumes? I am in the process of building a place to cast. mine will have three sides and a top(this is where i plan to mount the fan or fans) and the exhaust hose. i found some 6" flex hose that i plan to use for the exhaust to the outside. the top of my hood will be approximately 16 inches from the top of my pot,and my table is 2ft by 2ft

[Wots]

just wondering if you have looked at the inline bilge blowersfor boats not sure of the cfm?

That is a good idea. Did a quick search and came up with this. Only problem is it is a 12 volt system.

4" BluMaxx Premium Bilge Blowers feature statically & dynamically balanced blades, extra shaft support, sealed & shrink wrapped inline motor, and molded wire relief for strong connections. All of those extra features add up to a quiet blower that lasts longer! Meets or exceeds appropriate safety standards issued by UL, NMMA, ABYC, USCG, and CE. This blower has a three year limited warranty... something you won't find on most OEM blowers! Generates 240 CFM to ventilate your engine compartment fast! Draws 4.5 amps at 12V, rated for an 8 amp fuse.
http://www.replacementboatparts.com/4bilgeblower.aspx

[Mk42gunner]

what kind of cfm do we need to move the lead fumes? I am in the process of building a place to cast. mine will have three sides and a top(this is where i plan to mount the fan or fans) and the exhaust hose. i found some 6" flex hose that i plan to use for the exhaust to the outside. the top of my hood will be approximately 16 inches from the top of my pot,and my table is 2ft by 2ft

Jimbo,

It isn't the lead fumes, (if you have the lead hot enough to vaporize, you have it about three times to hot) as the odors from the fluxing/ reducing agent you are using.

To the original poster, my thought was using the fan from a dust collector stup for a woodworking shop. I think they are designed to run with four inch ducts. My self I just open a door and put a box fan in it to suck the air out.

Robert

[41 mag fan]

I went to Menards today, looking around. I'm planning here hopefully in the next week to finally get my casting set up complete in the shop.
I'm going to use an inline vent fan that's 6" and will reduce it down to 4" to go thru the wall of the shop. Then i'm going to put either a dryer vent on the outside of the wall or i might go thru the lowered roof of the shop and thru the soffit of the garage with a dryer vent made for the soffit.

Total cost might be $60. Probably less though.

[pt4u2nv]

I went to Menards today, looking around. I'm planning here hopefully in the next week to finally get my casting set up complete in the shop.
I'm going to use an inline vent fan that's 6" and will reduce it down to 4" to go thru the wall of the shop. Then i'm going to put either a dryer vent on the outside of the wall or i might go thru the lowered roof of the shop and thru the soffit of the garage with a dryer vent made for the soffit.

Total cost might be $60. Probably less though.

I think that is probably what I am going to do also after talking to an HVAC tech friend of mine. My casting area is a 12' x 24' garage with my bench at the back end along the 12' length. I have the ability to just cut a hole in the back wall to place a 4" dryer vent and mount an inline fan above me using flexible hose which I will try hanging just above my pot(s) and / or use the vent hood as a capture hooked into the flexible hose. I can get a 6" fan rated at 420CFM and reduce it down to 4". Will keep you posted on how it works out.

[cajun shooter]

You have overlooked the best source. Go to Lowe's, Home Depot or any large building store. Find the attic gable fans. They have over 1650 cfm and are good for 2200 feet. They are put into attics and my set up not only pulls out the fumes and bad things but it also brings the inside temperature down by 15-20 degrees. That is the main design of them. I cut a 16 inch hole in the side of my 12'X 24' shop just above my casting bench and installed the fan. They have a wire cage around the blades. They also come with a very good thermostat that you may regulate even when not casting. The outside grill that is extra to purchase comes with louvers that open when the fan comes on and close when it stops.
This is for casting and not smelting as has already been posted. All of your smelting should be done in a outdoor setting only.
With my fan coming on while casting, I actually feel a breeze coming from behind and even though I 'm sitting in front of my pot I see all the fumes and smoke being pulled to the outside.
Later David

[pt4u2nv]

Cool idea ! That is what is so great about this forum. I will definetly have to check that out !! Thanks

[jsizemore]

Jenn Air has a vent fan for their slide in ranges with downdraft ventalation. Has a 6" intake and 5" discharge. Also has brackets for mounting to the floor. I used a 4" dryer duct exhaust cover on the exterior wall and a 4" to 5" duct adapter in the wall and mounted the fan with floor mount brackets to 2 cleets on the wall. I mounted it with the intake aimed at the lead pot.If the fan intake needs to be closer, I'll add a piece of 6" aluminum duct. It runs on 115 volts and pulls 2.83 amps so it doesn't cause an overload of the lead pot's circuit. I wound up with 2 vent fans and hi-temp wire and solderless connectors and insulation from 2 ranges I scraped.

[rl69]

I use a old vent hood it pulls just fine for smelting and casting plus it gives me me a little more light

[oldtoolsniper]

You have overlooked the best source. Go to Lowe's, Home Depot or any large building store. Find the attic gable fans. They have over 1650 cfm and are good for 2200 feet. They are put into attics and my set up not only pulls out the fumes and bad things but it also brings the inside temperature down by 15-20 degrees. That is the main design of them. I cut a 16 inch hole in the side of my 12'X 24' shop just above my casting bench and installed the fan. They have a wire cage around the blades. They also come with a very good thermostat that you may regulate even when not casting. The outside grill that is extra to purchase comes with louvers that open when the fan comes on and close when it stops.
This is for casting and not smelting as has already been posted. All of your smelting should be done in a outdoor setting only.
With my fan coming on while casting, I actually feel a breeze coming from behind and even though I 'm sitting in front of my pot I see all the fumes and smoke being pulled to the outside.
Later David

Not sure this would be so much fun when it's 25 below outside, heck even at zero I'm not to fond of the wind at my back!

[oldtoolsniper]

Just took this of my yard!