LumberJocks

Trash can collection

  • Advertise with us

« back to Power Tools, Hardware and Accessories forum

Forum topic by Fuzzybearz posted 01-13-2019 01:30 AM 1195 views 0 times favorited 32 replies Add to Favorites Watch
View Fuzzybearz's profile

Fuzzybearz

104 posts in 582 days


01-13-2019 01:30 AM

Hi guys.

Been a while anddd slowly moving along with my dust collection. I’m wondering if I need to make an “exhaust” in my garbage can.

Right now the setup is piping into my dust collector into my garbage can. The way I see it, the DC is sucking in a lot of air and dumping it into the garbage can, where does that air go? Its just dumping into my garbage.

I don’t need secondary filter as this is outside in my shed. So if I need to make an exhaust, what size should it be? Right now my dust collector sucks in at 8”. Then it pushes into my garbage can with 5” piping. There used to be two 5” outlets out of my DC but I blocked one off


32 replies so far

View TungOil's profile

TungOil

1333 posts in 1008 days


#1 posted 01-13-2019 03:31 AM

You definitely need a place for the air to go. Rocker used to sell a trash can cyclone kit but I have not seen it lately on their website. You could create your own with two 90 deg PVC el’s Cut into your lid to create a cyclone effect.

-- The optimist says "the glass is half full". The pessimist says "the glass is half empty". The engineer says "the glass is twice as big as it needs to be"

View ibewjon's profile

ibewjon

1007 posts in 3306 days


#2 posted 01-13-2019 04:13 AM

What goes in must come out. How is the lid staying on? The cyclone lid is all over the internet for about $30, but it uses 4” piping. And it is normally placed before the collector to keep most material out of the fan and filter. Did you remove the bags and run pipe to garbage? What filters the chips and dust out? Are you trying to dump material into garbage can? I changed my old north state chip collector with bags to a modern collector by buying the jet pleated filter kit and added the jet chip deflector when it became available..now I have a DUST collector. I have 5” ducts with 4” taps to the machines. If I would dump the air outside, I could never heat my shop in winter or dehumidify it in the summer. Post a picture of your dust collector, not the trash can please, so we can better understand what you have set up.

View Fuzzybearz's profile

Fuzzybearz

104 posts in 582 days


#3 posted 01-13-2019 04:13 AM

Well I dont need a cyclone. That trash can is to replace the bags that were there. It’s located after the dust collector system.

I’m just wondering if i need to somehow vent the air out that’s being pushed into the can.

View WoodES's profile

WoodES

152 posts in 2203 days


#4 posted 01-13-2019 05:34 AM

You’ll not only need a vent outlet, but also a pressure drop. The drop in pressure allows the solids (e.g. dust, chips, loose change, etc.) to fall out of the air stream. The inlet and outlet should be the same diameter, thus the inlet and outlet air volume (measured in cubic feet per second, cfs) are roughly the same (without getting into the details of fluid mechanics, losses in the system etc.). However the expansion in the receptacle creates a pressure drop to release the solids.

Grizzly has a trash can separator, however you can build one out of many different materials, styles…

View WoodenDreams's profile

WoodenDreams

749 posts in 423 days


#5 posted 01-13-2019 06:51 AM

If you go to the blog or video tab and do a search for dust collection, you’ll see some advise to help.

View ArtMann's profile

ArtMann

1436 posts in 1329 days


#6 posted 01-13-2019 03:28 PM

I don’t know what to say except that you really need to get local help from someone who understands the subject or simply copy what other people have done. I don’t think you will be able to get enough understanding to make this stuff work well from an internet forum.

View Fuzzybearz's profile

Fuzzybearz

104 posts in 582 days


#7 posted 01-13-2019 04:52 PM

Again i’m not looking to create a cyclone. The trash can is located after the dust collector, if you look to the left of the garbage can in the picture you can see the dust collector. I do not need to separate out the chips, I just want to dump everything in the garbage can and let the small particles go anywhere since it is located Outside.

I think ibewjon said it best of “what goes in must come out” and “how is the lid staying on”
This means I have to create the outlet which will also most likely dispense the fine particles. As for the plan for the trash can lid, I was thinking ratchet straps. That was a question I was going to pose later.

The reason I can’t really find good examples anywhere is that people either use a cyclone, or just dump everything outside and not into a garbage can. I know i’m not the only one using this, just difficult to find similar projects.

Just to recap everyone, I do not need to separate anything. This garbage can is located in my outside shed so I just everything to be dumped into it and i don’t mind if the small particles are released into the air since it is outside. The picture of my dust collector is to the left of my garbage can in the pictures.

View ibewjon's profile

ibewjon

1007 posts in 3306 days


#8 posted 01-13-2019 05:23 PM

If I understand you correctly, you have removed the filter and collection bags and are trying to blow everything outside and hope to collect the largest chips. If so, I would drill a bunch of holes in the can to let the airstream dissapate. Start with some and add more to get results you are happy with. You have a unique situation here. You must have a large HP collector as most articles I have seen use 5” for a home shop size collector, 2 or 3 hp.

View woodbutcherbynight's profile

woodbutcherbynight

5974 posts in 2921 days


#9 posted 01-13-2019 05:24 PM



I just want to dump everything in the garbage can and let the small particles go anywhere since it is located Outside.

I think ibewjon said it best of “what goes in must come out” and “how is the lid staying on”
This means I have to create the outlet which will also most likely dispense the fine particles. As for the plan for the trash can lid, I was thinking ratchet straps.

- Fuzzybearz

How about a stove pipe that goes up and out of the top. Keeps it simple since you already have cut into the top once. The particles will fall down, the air will vent up and out and you are done.

Bungee cords would work and less hassle to get on and off.

-- Live to tell the stories, they sound better that way.

View Fuzzybearz's profile

Fuzzybearz

104 posts in 582 days


#10 posted 01-13-2019 09:04 PM



If I understand you correctly, you have removed the filter and collection bags and are trying to blow everything outside and hope to collect the largest chips. If so, I would drill a bunch of holes in the can to let the airstream dissapate. Start with some and add more to get results you are happy with. You have a unique situation here. You must have a large HP collector as most articles I have seen use 5” for a home shop size collector, 2 or 3 hp.

- ibewjon

Well I’m about to test the internets claims and real life. The outlet of my DC is 8” but all the calculators online say that’s too large and it can only run 6” max. It’s a PM 1500 and 3hp

I just want to dump everything in the garbage can and let the small particles go anywhere since it is located Outside.

I think ibewjon said it best of “what goes in must come out” and “how is the lid staying on”
This means I have to create the outlet which will also most likely dispense the fine particles. As for the plan for the trash can lid, I was thinking ratchet straps.

- Fuzzybearz

How about a stove pipe that goes up and out of the top. Keeps it simple since you already have cut into the top once. The particles will fall down, the air will vent up and out and you are done.

Bungee cords would work and less hassle to get on and off.

- woodbutcherbynight

I’ll keep the bungee cords in mind. The stovepipe is what I was also thinking. The unfortunate thing is that my HVAC is right next to it outside. But regardless I’m going to try to aim it away and see

View Fuzzybearz's profile

Fuzzybearz

104 posts in 582 days


#11 posted 01-14-2019 12:43 AM

Well no need for bungee cords as of yet. I did a dry run and the lid doesn’t come off. I added the “stove pipe”. Gets only 800cfm at the first 5” drop though so I may have leakage somewhere

View Fuzzybearz's profile

Fuzzybearz

104 posts in 582 days


#12 posted 01-14-2019 12:47 AM

Scratch that. Did a retest at 5” and it’s 1000 cfm

View tmasondarnell's profile

tmasondarnell

116 posts in 2302 days


#13 posted 01-14-2019 02:19 AM

Fuzzybearz,

I don’t doubt your measurements, but I am trying to understand how you are getting 800 cfm or 1000 cfm exhausting into a 32 gallon trashcan without it blowing the lid off. Some quick back of the envelope math says that at 800 cfm, you should be replacing the volume of that can 3 times every second.

If you are exhausting it outside, who worry about the can at all? Just let the chips fall where they may

View Fuzzybearz's profile

Fuzzybearz

104 posts in 582 days


#14 posted 01-14-2019 02:53 AM

I have a 4” exhaust on the trash can. Does that seem more plausible?

As for letting everything vent outside, it’s my side yard and I have a car there along with my hvac unit so I want to keep my hvac going and car cleanish : )

One thing I wonder, I have the dust collector at 8” and it’s pushing air into the garbage can at 5” and the outlet is 4” am I somehow restricting something? I feel if anything I should add another exhaust as I blocked off the 5” exhaust on the other side of the DC to push it to just one side.


Fuzzybearz,

I don t doubt your measurements, but I am trying to understand how you are getting 800 cfm or 1000 cfm exhausting into a 32 gallon trashcan without it blowing the lid off. Some quick back of the envelope math says that at 800 cfm, you should be replacing the volume of that can 3 times every second.

If you are exhausting it outside, who worry about the can at all? Just let the chips fall where they may

- tmasondarnell


View Fuzzybearz's profile

Fuzzybearz

104 posts in 582 days


#15 posted 01-14-2019 04:02 AM

Also, I did my calculations based on pie r squared x velocity x 60sec = cubic ft/min

4/12 or 5/12 or 6/12 (dependent on the size of the drop)

(( x /12) / 2 ) squared) x pie x 60 sec x measured velocity in ft/s

For example for a 5” drop I got 100 ft/s

((5/12) / 2) squared ) x pie x 60 sec x 100 ft/s = ~1000 cubic ft/min

And the meter I used was purchased off amazon for $20 so while it may be inaccurate, it swings both ways so it may have overstated or understated the velocity.

showing 1 through 15 of 32 replies

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com