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Forum topic by John_G posted 12-11-2013 02:51 PM 2073 views 0 times favorited 29 replies Add to Favorites Watch
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John_G

160 posts in 2155 days


12-11-2013 02:51 PM

Topic tags/keywords: dust harbor freight

Hey everyone,

I’m looking to purchase the ever popular Harbor Freight 2HP dust collector. I’m currently just using a large shop vac hooked up to a home made thien serperator on a steel trash can. It’s works ok i guess, the shop vac obviously can’t keep up with some larger tools as it just doesn’t have the power. So i’d like to upgrade and i know there have been sooooo many rebuilds on the HF Dust collector but i still have a questions.

I usually see everyone talking about getting a cartraige filter to put on it. This reduces the amount of fine dust back into the room. I have a different approach. I would like to just run out line out/vent directly outside, just like a dryer vent. This way i will get ZERO dust back into the shop. This seems like the best move and i’m just wondering what you all think and why no one else seems to do the same.

Thanks in advanced everyone.
John

-- John Gray


29 replies so far

View hydro's profile

hydro

208 posts in 1215 days


#1 posted 12-11-2013 03:39 PM

You will be blowing a lot of heat outdoors up there in the cold NY winter. Keep that in mind when designing the vent system.

-- Minnesota Woodworkers Guild, Past President, Lifetime member.

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John_G

160 posts in 2155 days


#2 posted 12-11-2013 03:42 PM

The vent would exit my basement a few feet above grade through the rim joist. I could add an elbow on the outside if i wanted to direct heat/dust but idk if it’s really neccisary. Not sure what the heat would do, i can’t imagine it’s like a dryer vent that puts out a lot of heat.

-- John Gray

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hydro

208 posts in 1215 days


#3 posted 12-11-2013 03:56 PM

Heat as in $$$$$

-- Minnesota Woodworkers Guild, Past President, Lifetime member.

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Dallas

3599 posts in 1951 days


#4 posted 12-11-2013 04:07 PM

Hydro is correct…. You are paying to heat and condition that air that you are just throwing away.

I use the 1HP HF unit, rated at 660cu.ft/min….. about 10 times what your dryer puts out. I think the 2HP unit is rated at 1100cu.ft./min…. probably equal to what your furnace blower can produce on it’s best day.

Next question, (And I’ll answer it, thankyouverymuch), where are you going to get air to make up what you are pushing outside? Ummm, the only place available….. The outside.
That means that you will have to intake unheated, unconditioned air to make up for what you paid to condition and heat in the first place.

Good luck to ya, I hope it works out.

-- Improvise.... Adapt...... Overcome!

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JAY Made

191 posts in 1508 days


#5 posted 12-11-2013 04:10 PM

Hey John,

I did this with my HF DC it works great. I used 5” stove pipe (I sealed all the joints with silicone caulk) for my exhaust because I didn’t want to restrict the exhaust. The only problem with using the 5” pipe was that there is no exhaust vent like the dryer vents, so I got a cap and drilled a bunch of 1/2” holes in it leaving just enough material to keep rodents out. Here is a pic of my set up.

I used the original ring and made a thein baffle so the larger material falls into the trash can. I attached the blower & motor on top. I have a small leak somewhere around the exhaust but have not had the time to address this yet. Even with the small leak my basement is almost dust free it’s great. Oh one other thing to think about is the location of your exhaust because a lot of the fine dust will can collect on your cars and other stuff ( I learned this the hard way, My wife thought there was some weird pollen on her car LOL)

-- We all should push ourselves to learn new skills.

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John_G

160 posts in 2155 days


#6 posted 12-11-2013 04:12 PM

OK so my shop is in my basement, so it’s not really a heated space. The intake for the vac would be from my machine, to the thien seperator on a steel can then to the blower and out the vent outside. So are you saying that the new fimes i have it turned on a week that it will pull sooo much air through my tool (planer, table saw, bandsaw) that it’ll suck all the warm air out of the room and cool the space? just want to make sure i’m following along here.

-- John Gray

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Smitty_Cabinetshop

13729 posts in 2082 days


#7 posted 12-11-2013 04:19 PM

John, I believe that’s the concern being stated. I’m with you, though. When the DC is run only intermittently, it’s not a significant factor.

-- Don't anthropomorphize your handplanes. They hate it when you do that. -- OldTools Archive --

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a1Jim

115202 posts in 3041 days


#8 posted 12-11-2013 04:22 PM

I have run my dust collectors out side for years,you avoid the expense of filtration systems,using up valuable floor space. I just built a litte shed to hold the barrel and bag that’s normally connected to the DC unit inside,this stops dust from blowing around outside .Unless you are running your dust collector all day I don’t think you have a signifacant heat loss.

-- http://artisticwoodstudio.com Custom furniture

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GShop

3 posts in 1095 days


#9 posted 12-11-2013 04:27 PM

Another issue to consider is location of water heater and furnace. If they are located in basement and you do not have sufficient intake air, you could create a negative pressure causing CO risk. Or, safety features on more modern appliances may shut down the unit.

View Dallas's profile

Dallas

3599 posts in 1951 days


#10 posted 12-11-2013 04:32 PM

Edit. I give up. Whether the DC is on for 3 minutes or 3 hours it will cost money to re-condition the air you use.
All of this is up to you. Personally I like efficiency and hate spending money that I don’t need to.
My filter cost $130, I have used it over a year, no need to clean it yet. I may need to clean it next year sometime.
How is that more expensive than throwing conditioned air outside?

OK so my shop is in my basement, so it’s not really a heated space. The intake for the vac would be from my machine, to the thien seperator on a steel can then to the blower and out the vent outside. So are you saying that the new fimes i have it turned on a week that it will pull sooo much air through my tool (planer, table saw, bandsaw) that it’ll suck all the warm air out of the room and cool the space?

Essentially, yes, although if you are working in your basement in New York in December and it isn’t heated, you are a better man than I Gungadin!
You say the intake for your vac would be from the tool. Hunh? You have a tool that can make it’s own air? Or are you saying that the tool is an opening for the ambient air to pass through so the DC can draw air from the area?
The air that passes through the tool, (the DC actually sucks air from the low pressure area of the tool to the exit).
Think of it this way… if your basement were perfectly sealed and you sucked all the air out, could you survive? Wouldn’t the basement implode?
Any air you take from the basement is being made up from someplace, probably from the heated spaces above because houses are not sealed internally, they must breathe from top to bottom.
The house can take in unconditioned air in a number of ways.
through the roof vents.
through the fresh air return of the furnace
through leaks in the building itself.
Or all of the above plus others.

-- Improvise.... Adapt...... Overcome!

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mbs

1606 posts in 2404 days


#11 posted 12-11-2013 04:33 PM

I have one that I run outside but weather isn’t an issue for me. It is very noisy though. Do you have neighbors nearby?

-- Sorry the reply is so long. I didn't have time to write a short reply.

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JAY Made

191 posts in 1508 days


#12 posted 12-11-2013 05:00 PM

Unless you are going to run it for long periods of time I think you wont have a problem. I have been running mine for 3 or 4 months now and I have a gas hot water heater. My DC is not on the entire time I am in my basement only the short period of time my tools are running. Also not sure how much room you have in your basement but if you are like me space is at a premium, the way I have set up my DC saved me a ton of space.

-- We all should push ourselves to learn new skills.

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bondogaposis

4028 posts in 1815 days


#13 posted 12-11-2013 05:08 PM

The big problem with that is the loss of heat in the shop. Say the typical 2 car garage workshop is 7200 cu ft and the HF dust collector is rated at 1550 cfm. Even if you cut that in half due to manufacturer optimism and friction loss due to duct-work, separator , etc. to 775 cfm you will completely change the air in your shop every 9 1/2 minutes. If your are spending a lot of money to heat your shop in winter, you will soon realize that this is an expensive idea. If your shop is in a climate where the difference between outdoor and indoor air temps are not great it is a good solution.

-- Bondo Gaposis

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John_G

160 posts in 2155 days


#14 posted 12-11-2013 05:53 PM

JayMade
That is exactly what i’m talking about, perfect. The vent will actually go into my backyard where there’s about a quarter acre of nothing. Glad to hear it’s working out for you.

-- John Gray

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JAY Made

191 posts in 1508 days


#15 posted 12-11-2013 05:57 PM

John,

If you have any questions let me know. While working on this I made a quick and easy circle jig for my router that worked wonderfully. I can send you pictures if you need them.

-- We all should push ourselves to learn new skills.

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