want to improve suction on my shop vac

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Forum topic by Walt posted 05-28-2016 06:43 PM 719 views 0 times favorited 11 replies Add to Favorites Watch
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211 posts in 2259 days

05-28-2016 06:43 PM

Topic tags/keywords: cyclone air handler question

I would like to make an improvement to my shop vac. by making an additional vacuum container. I remember seeing one made out of an old 5 gal paint bucket. However I can’t remember where I saw the plans. I know it used PVC pipe and 90 degree elbows to make the cyclone air movement.

Can anyone remember the source or has anyone made one of these? If you had I would be interested in the results.

-- Walt Wilmington Delaware,

11 replies so far

View clin's profile


485 posts in 417 days

#1 posted 05-28-2016 08:07 PM

Adding anything to your shop vac will reduce airflow, not increase it, with one exception.

It sounds to me like you are talking about adding a Thien baffle (lots of info in LJ about those). These are a form of separator to collection the majority of chips and dust. The main purpose is to prevent the fine filter (or shop vac filter) from plugging up so fast. So they reduce the frequency of having to clean the filter.

The exception, if your shop vac filter clogs quickly and therefore reduces airflow, then adding a separator may result in overall more airflow if it allows you to keep the vac filter cleaner. But a separator will reduce airflow, all other things being the same.

-- Clin

View Tennessee's profile


2410 posts in 1935 days

#2 posted 05-28-2016 08:13 PM

Clin: Are you saying that dropping the majority of chips and debris prevents them from reaching the filter?
That makes sense, save that it seems like the stuff that clogs up my shop vacs is the really fine stuff that tends to cover the paper and would blow right by a primary drop-out chamber.

And since I went to Hepa style filters on my shop vacs, they obviously lose suction a bit faster. I’d want to know how to maintain air flow and prevent the fines, (and I mean really fines), from clogging up my filters.

How may times have I emptied out a vac only to find that it was only half full, but the filter was clogged completely. Argh…

-- Paul, Tennessee,

View clin's profile


485 posts in 417 days

#3 posted 05-28-2016 11:25 PM

I use a Dust Deputy (small cyclone) on my shop vac, shop vac bag, and a HEPA flter. The HEPA filter never seems to have much of anything on it, ever. And the bag has nothing in it that I can tell without opening it up. I’m sure there is some fine dust inside the bag, but it’s certainly not filling up.

There is a range of effectiveness with separators. The Oneida Dust Deputy is know to be very, very good. This of course is why I got one. And as I understand it separators like a Thien baffle work pretty well, but not as well as a good cyclone.

I strongly recommend a Dust Deputy for a shop vac. Of course it makes an already clunky tool (the shop vac) even more difficult to move around. I bolted my Dust Deputy to the side of my 16 gal Ridgid vac. Unwieldy is putting it kindly. Others have built carts and stacked the vac and cyclone. At least making the footprint smaller and the whole thing a single more stable unit to move when needed.

I did get a 20 ft hose, so I can reach anywhere in my shop without have to move the vac. This works well. But then of course you have 20’ of hose getting in the way.

-- Clin

View Walt's profile


211 posts in 2259 days

#4 posted 05-29-2016 12:39 AM

My shop vac is connected to my miter saw. It works about as well as can be expected. Because of the fine dust. Created by this saw the vac filter clogs quickly. I need an inexpensive way to get longer life out of the filter

-- Walt Wilmington Delaware,

View BB1's profile


421 posts in 268 days

#5 posted 05-29-2016 01:29 AM

I have found a cyclone to be very helpful in catching the chips and material that otherwise clogged up my vacuum. Have mine mounted above my vac (thanks to Jay Bates plan with slight modifications based) and it rolls wherever I need it without taking much more room than the vacuum did.
Have recently added a second by my husband’s lathe but repurposed a grill stand for a side by side configuration

View Walt's profile


211 posts in 2259 days

#6 posted 05-29-2016 02:03 AM

BB1 that is a great way to save space. What I am looking for is plans for using a 5gal. Bucket ans PVC pipe for a cyclone attachment .

-- Walt Wilmington Delaware,

View BB1's profile


421 posts in 268 days

#7 posted 05-29-2016 02:26 AM

My stand was based on a youtube video by Jay Bates. I wasn’t up to trying to build my own cyclone so I purchased mine after checking online reviews and watching a review by the Wood Whisperer on youtube.

View Lazyman's profile


611 posts in 808 days

#8 posted 05-29-2016 02:44 AM

My dust separator sort of matches your description. You can see a pic if you scroll down this thread:
I made this as an experiment using 2 buckets, a piece of plywood and PVC I just had laying around. It is ugly but works so well I still use it. It is basically 2 buckets with a Thien baffle between them. I used a 45° angle PVC fitting to inject the air stream into the top bucket to achieve the cyclone affect. I always intended to make it a little more finished looking but since it works so well, I just never have. It doesn’t improve suction but does extend the life of the filter by keeping all but the finest dust out of the vac. I can even use this to capture chips from my dewalt jointer. I only clean the filter in the shop vac about every 5 or 6 times the buckets fill up. It probably doesn’t work as well as the dust deputy but only cost me about $5 since it’s made with stuff I had laying around.

BTW, I also highly recommend a clean stream filter ( I use the wet/dry one because I can wash it off when it finally gets covered with dust. You can just blow it off too but that gets pretty messy. It’s more expensive than the standard filters but is over 2 years old and still works like new so ends up being cheaper over the long run.

-- Nathan, TX -- Hire the lazy man. He may not do as much work but that's because he will find a better way.

View JBrow's profile


748 posts in 340 days

#9 posted 05-29-2016 03:10 AM


I echo the prior recommendations for the Dust Deputy. It does a great job keeping the HEPA filter of the shop vac “clean”. I cleaned the filter after over a year in service for the first time. It was much cleaner than before the Dust Deputy, when the filter required cleaning about monthly and I used the shop vac less frequently (trying to protect the filter from debris). Unfortunately the complete kit is about $100.

The 5 gallon bucket with cyclone air flow may help keep your filter cleaner longer, but I suspect the 5 gallon bucket will need emptied before it is half full, otherwise large previously separated debris will probably make it to the filter.

A 5 gallon cyclone action bucket lid can be purchased for about $25.

Otherwise a 90 degree PVC fitting and a straight fitting through the lid, with the fittings arranged as shown on the Woodcraft photo will probably result in the cyclone action within the bucket.

View bigblockyeti's profile


3572 posts in 1141 days

#10 posted 05-29-2016 03:27 AM

How long do you want it to last? You can plug it into 240V and the suction will be much better, the life of the shop vac will not.

View jgt1942's profile


136 posts in 1309 days

#11 posted 07-11-2016 03:25 AM

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