Shopsmith Forums

No landlord, I'm trying to never do that again. Along with a main obstacle, that was a one time mistake.



If I cut through the door, I'd need to find a proper filter for dust. If I do like Dennis says and use an exhaust fan, guess I could pipe it through the attic and out the eve. I was worried about pressures with a collector going.

Dennis, is your room completely sealed except for the air vent and exhaust ?

beatnik wrote:No landlord, I'm trying to never do that again. Along with a main obstacle, that was a one time mistake.

]Dennis, is your room completely sealed except for the air vent and exhaust ?[/color]

No, it's not well sealed at all. There's a roughly half-inch gap underneath the french doors. There is a wall (unfinished on my side) between it and my wife's adjacent scrap-booking room, and there are gaps over the top of the wall plenty big enough to pass through extension cords and such. I was a bit surprised that the exhaust fan was 100% effective at controlling fumes, but it's apparently big enough to make sure that air only flows into the room through all those gaps.

Now if I forget to close the HVAC vent, that's a different story. The forced air entering the room will indeed push fumes out into the rest of the house.

You could achieve the same effect by using a dust collector that exhausts outdoors. But that could move enough air to be a very expensive proposition -- if you exhaust it outdoors, hot/cold/humid outside air has to come back into the house somewhere else.

Using a self-contained dust collector inside of the room should not be a problem, and is exactly what I do. Any pressure differentials that it creates are very localized, and are entirely within the room.

A small $75 5,000 btu window air conditioner would solve all your problems. In outside vent mode it would exhaust any fumes and develop negative pressure to ensure no dust would escape under the closed door into the rest of the house. You could then seal off your central AC register. And you could buy a whole box of filters for almost nothing. The only question is do you have enough power to run everything.

Here is the problem with forced air, air conditioning air is blown into the room, a like volume of it must be drawn back into the HVAC unit. If you are making dust it will be dust ladened. That dust will deposit on everything on it's way back to the HVAC unit.

The air conditioning coils in the HVAC in high humidity climates will be damp. That dust will collect to that dampness and make mud. That mud will eventually clog up the air passages through the coil and your AC will stop.

If you prevent the air from leaving the room and flowing back to the HVAC eventually you will not have AC in the room as air pressure equals that coming for the HVAC unit prevnting cool air from coming in.

If you blow the air outside you will be air conditioning the outside. And as you blow more air outside you will be drawing in air from outside in and again reducing the efficiency of the AC.

I deal with these problems all the time with the window AC in my garage/shop. I had to cobble up extra filters but even then I have to take the AC apart every year and clean the coils. If I use a blower to vent the air out of the garage the incomming air is hot enough to overcome the cooling effects of the AC and I sweat. I have two dust collectors running most of the time and even then the coil of the AC unit get dirty real quick.

But because it is a window unit cleaning the coils is easy. Not so in house HVAC

When I lived up north I had a basement. I knew to turn off the HVAC when I worked in it but one time I painted something red. At the top of the stairs from the basement to the house was white tile. When I finished I had pink tile. Luckily I saw it before old whats her name did and I got it cleaned up.

I then installed a explosion proof fan to vent out the window. Worked fantastic. So I finished the project with the red paint. That is when I noticed my neighbors white house was a funny shade of pink. Luckily for me the house was far enough away that when the paint particles got there they were dry. So just hosing off the house solved the problem.

I then built some really nice air filtering system and never had the problem again.

Since you don't have to worry about the lady of the house do what you want just be prepared to clean the HVAC coils or have it done and have the dust deposited through the house.

If it were me I would seal the room and use a window AC unit to keep it cool.

So we're back to a window unit or a hole in the door. HOA wont allow a window unit, it would have to be concealed inside somehow.

I have to ask, is there not a filter that would stop all dust from passing through a door vent ?

Outside the HOA is my only main obstacle. I pay them monthly to nag me.

beatnik wrote:So we're back to a window unit or a hole in the door. HOA wont allow a window unit, it would have to be concealed inside somehow.

I have to ask, is there not a filter that would stop all dust from passing through a door vent ?

My HOA also doesn't allow Window units. They did allow my ductless split unit because it looks just like a standard central unit from the outside and you can place it anywhere to hide it if need be.

After turning and sanding 90 bowls I finally had a chance to look at the builtin filter. It was clogged, as expected, and the coils were also mostly plugged up. My shop vac made quick work of cleaning that mess up. I now know to check the filters more often in the future.

The problem with using a filter in the door option is that a standard central A/C system is balanced to distribute the air evenly by design. If you disrupt the standard design, which normally is a free flow of air via either an open door or a large gap at the bottom of the door, and restrict the normal flow from the room to the return air inlet by introducing a filter in the door, which by design will reduce the free flow of air if it's doing it job right, you might find the air flow reduced and the cooling effect greatly reduced. You will find yourself lowering the thermostat because the temp in your room is higher than it used to be due to the restricted air flow which then cools the rest of the house more than necessary. Of course this is all just my opinion and I could be completely wrong. Then of course you have all the new sources of heat from the motors which will require even more cooling to offset.

beatnik wrote:Outside the HOA is my only main obstacle. I pay them monthly to nag me.

So your internal obstacle has been replaced with an external one.


Solution, move!;) Find a place with no HOA to harass you.

beatnik wrote:So we're back to a window unit or a hole in the door. HOA wont allow a window unit, it would have to be concealed inside somehow.

I have to ask, is there not a filter that would stop all dust from passing through a door vent ?

Even without running the exhaust fan, I have very little problem with dust migrating. My dust-collection system has three filtration stages:
#1: Dust Deputy cyclonic separator
#2: Filter bag inside a large shop vacuum
#3: HEPA output filter in the shop vacuum (downstream of the filter bag).

Almost nothing gets through that HEPA filter. And the Dust Deputy does such a good job, I very rarely have to change the vacuum bag or clean the HEPA filter.

Before I had this setup, I used the same shop vacuum for dust collection, but with only a standard exhaust filter and nothing else. The fine dust went right through the filter and made a mess everywhere. Presumably including my lungs.

Solvent fumes are a different matter entirely. Ordinary filters are no help. In theory, I suppose there may be charcoal filters or some such that would absorb them. But I don't know of any practical solution other than venting them outdoors.

I was thinking of building a Thien like this one to separate most of the dust.

http://www.youtube.com/watch?v=3QCAOwSqrko

I wonder how big a filtered door vent it would take to equal out the hvac and what filter/material I would use ?

Maybe build some kind of room air filtration box ?