Casting ventilation

[41 mag fan]

Hopefully someone with knowledge or a heating /air guy will chime in on this question.

I'm looking to build a venting system, so I can cast in my shop instead of in the garage door opening.
I noticed at Menards while wandering around last Sunday, an inline duct fan.

They carried a 6" and 8" fan.
Will one of these fans be adequate enough to suck the fumes out? I'll only have maybe 3-4' of air duct from my hood vent over the pot(s), to the wall then maybe 3-4' of pipe to where it'll be above the eaves on the shops roof.
Thanks for any input on this.

[shadowcaster]

41 mag fan,
I'm not a heating / air guy by any means, but I it is possible to use an inline fan in the ducting from your vent hood. I use a 500 cfm inline fan in mine with no trouble and excellent draw. My distance from hood to outside is only about 4 feet. I think that proper shape of the vent hood is more important than how powerful the fan is, (To a point) so that the fumes and smoke move naturally towards the ducting before they reach the pull of the fan. This link has some picks of my hood and set up. Good luck :-)

Shad

http://castboolits.gunloads.com/showthread.php?t=146065

[smokemjoe]

I once used a blower system off a kitchen fan above the stove, I had it on chains and it was above the pot 6 in. You still had the smell from the lead but no smoke got into the room. Basement,Worked great until the wife pulled the pull and said no more after 40 years in the house,

[41 mag fan]

41 mag fan,
I'm not a heating / air guy by any means, but I it is possible to use an inline fan in the ducting from your vent hood. I use a 500 cfm inline fan in mine with no trouble and excellent draw. My distance from hood to outside is only about 4 feet. I think that proper shape of the vent hood is more important than how powerful the fan is, (To a point) so that the fumes and smoke move naturally towards the ducting before they reach the pull of the fan. This link has some picks of my hood and set up. Good luck :-)

Shad

http://castboolits.gunloads.com/showthread.php?t=146065


I remember coming across that thread here awhile back. Your hood is very similar to the one I'm looking at putting up, except mine will be one you'd use as duct work in a home.
I'm looking at maybe having my hood 3' high off the top of my pots, enclosed on 3 sides, so fumes will naturally go up.
That fan you have, is it the type they put in duct work of homes?
I might go and look at the CFM's on it this weekend.

[jlucht01]

I built an enclosure around my Pot and hooked a bathroom vent to the top. I installed a dryer vent on the out side of the house and hooked the dryer vent hose to the bathroom vent. Works good. I'll post some pics later tonight.

[heavyd]

I bought a 10" duct booster fan that does 410 cfm. Built a 2x4 frame around it and put it in my basement window. Put a 10 to 8 reducer and then a L duct. Then a 8 to 6 reducer and a 6 inch flexible aluminum duct down to the top of my furnace. With the flexible duct I can move it around, rase and lower to keep the ducting where I want over my pot. The 410 cfm is perfect. I would not want any less and would not pay for any more. I can flux with sawdust and not get any smell in the room above my casting equipment. I will try and remember to post a picture when I get back home on Friday.

Regardless of how you set up your ventilation, it is well-worth the cost to be able to cast indoors. I can cast all day long in comfort and can keep my equipment set up all year long in the basement.

[shadowcaster]

41 mag fan

I remember coming across that thread here awhile back. Your hood is very similar to the one I'm looking at putting up, except mine will be one you'd use as duct work in a home.
I'm looking at maybe having my hood 3' high off the top of my pots, enclosed on 3 sides, so fumes will naturally go up.
That fan you have, is it the type they put in duct work of homes?
I might go and look at the CFM's on it this weekend.

My inline fan is the type used in home ducting as a booster. It's 8 inches in diameter and they sell them at home depot and at lowes. I had to raise mine a bit as I stand 6 foot 5, and didn't want to be banging my head or be ducking all the time.

Shad

[Adk Mike]

I have a work shop with a casting area build over the bench. My shop is 20 by 25 and heated. I cast all winter off and on. The work bench has a kitchen range hood vented outside with a two speed fan just like in a kitchen. It works great and I got the hood for free. Mike

[shadowcaster]

Adk Mike

I have a work shop with a casting area build over the bench. My shop is 20 by 25 and heated. I cast all winter off and on. The work bench has a kitchen range hood vented outside with a two speed fan just like in a kitchen. It works great and I got the hood for free. Mike

Sounds like a sweet setup for Casting. My experience with Smelting, especially with dirty wheel weights, is that something more heavy duty is required for adequate ventilation.

Shad

[Lefty SRH]

Is the ventilation for extra precaution? I have been assured (from this sight) that the casting temps we normally run don't give off the harmful/toxic lead fumes. I cast in my garage and smelt outside in the fresh breezy air.
I'm not trying to start a debate/argument, I'm just asking.

[shadowcaster]

Lefty SRH

Is the ventilation for extra precaution? I have been assured (from this sight) that the casting temps we normally run don't give off the harmful/toxic lead fumes. I cast in my garage and smelt outside in the fresh breezy air.
I'm not trying to start a debate/argument, I'm just asking.

The need for ventilation, IMHO becomes necessary while smelting indoors due to other things attached to the lead, like paint, oil, grease, dirt or any other number of things it has come in contact with. When these burn lots of smoke can be created, and the fumes most likely will be toxic and without ventilation it will fill the shop. Been there, done that... It's not real pleasant. Even when fluxing, smoke is generated.

Shad

[41 mag fan]

41 mag fan


My inline fan is the type used in home ducting as a booster. It's 8 inches in diameter and they sell them at home depot and at lowes. I had to raise mine a bit as I stand 6 foot 5, and didn't want to be banging my head or be ducking all the time.

Shad

Shad.....That's the same type I was looking at but it was from Menards. They had the 6" and 8"
Does that fan, have enough ooomph to suck all the fumes and smoke out?





I bought a 10" duct booster fan that does 410 cfm. Built a 2x4 frame around it and put it in my basement window. Put a 10 to 8 reducer and then a L duct. Then a 8 to 6 reducer and a 6 inch flexible aluminum duct down to the top of my furnace. With the flexible duct I can move it around, rase and lower to keep the ducting where I want over my pot. The 410 cfm is perfect. I would not want any less and would not pay for any more. I can flux with sawdust and not get any smell in the room above my casting equipment. I will try and remember to post a picture when I get back home on Friday.

Regardless of how you set up your ventilation, it is well-worth the cost to be able to cast indoors. I can cast all day long in comfort and can keep my equipment set up all year long in the basement.


Where'd you get the 10" fan at? When I was in Menards last Sunday all they had was the 6 & 8" fans.

And I agree about the worth the price to be able to cast inside. I was chompin at the bit all winter for it to warm up, and each time thinking...if I only had my vent set up

[birdadly]

Shad.....That's the same type I was looking at but it was from Menards. They had the 6" and 8"
Does that fan, have enough ooomph to suck all the fumes and smoke out?

Where'd you get the 10" fan at? When I was in Menards last Sunday all they had was the 6 & 8" fans.

I was just looking at Menards too. I may have messed up, as I just put a 4" hole in the side of my house and stuck a dryer vent thing there, with a flexible tube going to my basement where I want to cast.

I (mistakenly now I know) bought a bathroom fan that was 50cfm and it's not nearly good enough. At Menards, they did have a 4" booster fan, but it was still only 80cfm.

Now I have to find out if I can somehow use the 6 or 8" booster fans... maybe just make the hole bigger going out my house??

The 6" was 250cfm and 8" was 500cfm I believe. -Brad

[41 mag fan]

I was just looking at Menards too. I may have messed up, as I just put a 4" hole in the side of my house and stuck a dryer vent thing there, with a flexible tube going to my basement where I want to cast.

I (mistakenly now I know) bought a bathroom fan that was 50cfm and it's not nearly good enough. At Menards, they did have a 4" booster fan, but it was still only 80cfm.

Now I have to find out if I can somehow use the 6 or 8" booster fans... maybe just make the hole bigger going out my house??

The 6" was 250cfm and 8" was 500cfm I believe. -Brad


Brad,
thanks for letting me know that!! That 8" is the way I'll go then. I believe here in IN they wanted $29 and change for it.
I looked at them but never really looked at them for the CFM's. It was just a light bulb went off and thought I'd post it on here, as I was sure someone had one installed.
Might be a way to keep the 4" hole and size it up where you'd put the inline duct fan at. Resize it to the pot or hood.
Only problem, I can see, as taking it from experience working with our ventilation fans for underground, you need to open up the size at the beginning, ie 8" from hood to inline fan, but you can choke it down to 4" aways away from fan.
At work, we have a 4- 6 entry opening 1 break, 100', from the fan, from there it goes to 3-4 breaks depending on where at, beginning about 5000' in. That stays that way all the way to all 3 units, which we have 2 units that are 5 & 7mi away from the fan.
So basically, inline duct maybe right above hood vent. About 6' or so away you could choke it down to 4". This way you reduce your air resistance in the beginning, but choking it down further out will increase air speed due to a funneling effect, causing it to move any fumes or smoke out quicker.
Basically it'd be like at work, so many breaks, maybe 1000' from the unit tops, we have a regulator, that forces air to move faster, by forcing it thru an opening that maybe 8-9'w x 5-12' high. Same would be for going from an 8" pipe to a 4" pipe
Of course i'm looking at a system at work, that puts out 350,000 CFM's vs one that does 500 CFM's. But the same basic principles ought to apply.
you could also, put the inline on a fan switch to regulate speed of the fan.

[35isit]

I cast in a 8'x8' heated shed. I use a bathroom fan vented straight out wall in fact dryer vent I use is hooked straight to fan without any hose. It sits just high enough above pot to ad ingots, flux and stir pot. It takes all smoke and smells out of the small building.

[Mal Paso]

I am in the process of replacing my 10" window fan (pot directly under) with something better. Is there really a need for large vent diameters and high CFM? I was thinking 3"-4" flexible aluminum duct right over the pot. There don't seem to be any fumes except at the pot and every Cubic Foot you blow outside needs to be replaced and if it's Cold that Cubic Foot needs to be heated.

I smelt and blend outside.

[heavyd]

Shad.....That's the same type I was looking at but it was from Menards. They had the 6" and 8"
Does that fan, have enough ooomph to suck all the fumes and smoke out?







Where'd you get the 10" fan at? When I was in Menards last Sunday all they had was the 6 & 8" fans.

And I agree about the worth the price to be able to cast inside. I was chompin at the bit all winter for it to warm up, and each time thinking...if I only had my vent set up

I got mine at JohnStone Supply. It's an HVAC supply in Marietta, Georgia.

You can get them at Northern Tool as well. They are much cheaper at a HVAC supply company though.
http://www.northerntool.com/shop/tools/product_200402935_200402935

[shadowcaster]

http://castboolits.gunloads.com/showthread.php?t=146065

I think that there seems to be some confusion here as to what ventilation is necessary for casting and for smelting. Hopefully this will help explain what I see as the differences. I built my vent hood to do both smelting and casting as shown in the pics in the link above.

I wanted to be able to smelt and cast indoors all year around. It's cool in the summer and warm in the winter. Smelting is a smokey, smelly operation. I built my hood to have the smoke and fumes naturally gravitate towards the ducting. The opening in my hood where it meets the ducting, is 14 inches and then adapts down to 10 inches and then to 8 inches. It then takes an immediate 90 degree turn, flows through the 8 inch, 500 CFM inline fan and on to the outside. The air/smoke/fumes speeds up as it flows through the decreasing size of the ducting and into the fan. Basically the venturi effect. Thus far, this has been more than enough air flow to handle all the smelting I have done. If for some reason the 500 CFM stops handling the job, I would then consider upgrading to a higher CFM squirrel cage blower.

As far as casting goes, this set up is WAY over kill. Small fans, dryer hose, window fans and the like should be able to handle any smoke/fumes without a problem.

I am no expert on any of this, but have found that this setup works well for me.

Shad

[41 mag fan]

http://castboolits.gunloads.com/showthread.php?t=146065

I think that there seems to be some confusion here as to what ventilation is necessary for casting and for smelting. Hopefully this will help explain what I see as the differences. I built my vent hood to do both smelting and casting as shown in the pics in the link above.

I wanted to be able to smelt and cast indoors all year around. It's cool in the summer and warm in the winter. Smelting is a smokey, smelly operation. I built my hood to have the smoke and fumes naturally gravitate towards the ducting. The opening in my hood where it meets the ducting, is 14 inches and then adapts down to 10 inches and then to 8 inches. It then takes an immediate 90 degree turn, flows through the 8 inch, 500 CFM inline fan and on to the outside. The air/smoke/fumes speeds up as it flows through the decreasing size of the ducting and into the fan. Basically the venturi effect. Thus far, this has been more than enough air flow to handle all the smelting I have done. If for some reason the 500 CFM stops handling the job, I would then consider upgrading to a higher CFM squirrel cage blower.

As far as casting goes, this set up is WAY over kill. Small fans, dryer hose, window fans and the like should be able to handle any smoke/fumes without a problem.

I am no expert on any of this, but have found that this setup works well for me.

Shad


What you got is something alot of us envy. I could expand my shop to accomodate a smelting operation, but at this time, I don't see that as an option.
The one thing I'm thinking I'll do is build a 3 sided box, with a vent in the top, that'll be angled so smoke and fumes will naturally travel to the vent hole.
The 3 sided box will be big enough to handle my 2 pots I have side by side.
The inline duct fan, I'll have on a variable speed control.
Now I just need to get busy on it.

[shadowcaster]

What you got is something alot of us envy. I could expand my shop to accomodate a smelting operation, but at this time, I don't see that as an option.
The one thing I'm thinking I'll do is build a 3 sided box, with a vent in the top, that'll be angled so smoke and fumes will naturally travel to the vent hole.
The 3 sided box will be big enough to handle my 2 pots I have side by side.
The inline duct fan, I'll have on a variable speed control.
Now I just need to get busy on it.

That sounds like it should do the job! Best of luck to you... :-)

Shad

[birdadly]

The one thing I'm thinking I'll do is build a 3 sided box, with a vent in the top, that'll be angled so smoke and fumes will naturally travel to the vent hole.
The 3 sided box will be big enough to handle my 2 pots I have side by side.
The inline duct fan, I'll have on a variable speed control.
Now I just need to get busy on it.

Maybe if I do this, my 4" hose with a 80cfm booster fan would be enough? If so, where about would I put the fan... near the hood top or nearer the exit of my house? It's something like a 4 or 5' flexible tube (dryer vent kit I believe). -Brad

[Mal Paso]

I went to HD and found a small Bath Fan for $13.97. I already had a chunk of 3" Aluminum Flexible vent, the wood, electric cord, weatherstrip and Silicone Calk. It fits in the sliding window and the stick left of the timer holds it closed. The vent just hangs outside but I may have to tie it down.

I had a Vortex fan in the window but as you can see the ground just drops away and during storms the East Wind would blow back in past the blades. Storms are the best time to cast. Keeps my trucks out of ditches.

It works well. I made an extra large cloud of smoke while fluxing and it removed every bit. It's pouring rain and it seems to be passing that test too.