If you want to see this project being made live there is a link to my video at the bottom.  Otherwise the meat 'n potatoes section is detailed for you below.  Either way, you'll end up with the same thing.

When I purchased ShopVac's 5HP, 16-gallon QSP model vacuum I was elated to discover you can use a filter bag in the canister. In the past these types of vacuums were supplied with a measly foam filter and a paper towel type of covering that quickly became caked with particulate matter and caused the vacuum to cease working. However, with a collection bag the vacuum is allowed to work continuously because stuff is trapped inside the bag and not around a filter at the motor.

It goes without saying that this was a vast improvement but these bags are used for dry pick-up only so you can imagine how fast they'll fill up in a woodshop environment, and at 3 for $14.00, they aren't cheap. So, I immediately set my mind to adapt the shop vacuum into something a little more suited for the environs of a woodshop and this change is the purpose of this article.

I thought that if I could put another canister before the vacuum itself to act as a pre-collector, then not only would I save on bags, but the volume of storage could at least double before having to empty the system. So, by using a fiber drum that I had on hand, I made a cyclonic pre-collector that can be used in conjunction with a standard shop type of vacuum.

As a result of it working so well, I speculated other woodworkers would be interested in making this handy shop accessory. This drawing is provided in case you have any difficultly in understanding my steps for construction. If any gray areas still exist, then by all means get with me and we'll hash it out together.

I was surprised to discover the ID of the ShopVac's 2 1/4" hose fitted perfectly around 1 1/2" schedule 40 PVC pipe, which eliminated the necessity of fancy adaptors. But your shop's vacuum may have different size hoses so alter the pipe size for your situation accordingly. As a little bonus these fiber drums have a metal lid and this lid is secured to the drum by a metal band. There is a clamp that is permanently attached to the band so that the combination of closing this clamp and an inner ring of sealant that is already on the lid allows for an airtight seal!

This project just aches to be made so let's get started, but before we use any power tools, let's take a moment to talk about shop safety.  Don't forget to wear these <.tap, tap> safety glasses.

The BOM is as follows:

1 - Fiber drum with metal lid and clamp
3'- 1 ½" PVC pipe
1 - 1 ½" PVC elbow
1 - 1 ½" x 5 x 5 scrap wood
1 - 2 x 2 x 10 scrap wood
¾" truss head or pan head screws
Wood glue
Neoprene weatherstripping
CNA glue
Caulk

 

1. Find a fiber drum - the size doesn't matter as long as it is in good shape but the one I used was 26 gallons.

2. Lay out and cut a hole in the center of the lid that will allow a pipe to extend through the lid and into the barrel (see Fig. 1 of my drawing).

3. Take a 5" square x 2" thick scrap piece of pine (or whatever) and put a hole in the center of it like you did in step 1. Use caution here to allow as little clearance for the pipe to pass as possible. Apply caulk, on the top of the lid, around the perimeter of the hole and secure the scrap piece of wood to the lid with screws.

4. Cut the pipe to allow for 1" to stick above the piece of wood and 1" below the intake pipe (see Fig. 2). Then glue the pipe to the scrap piece of wood (I used a CNA type but epoxy will work as well). At this stage, you're finished with the lid, put it aside and let's proceed with the barrel.

5. About 2" below the metal band at the top of the barrel you need to cut an elliptical hole to allow another piece of pipe to pass through. Again, allow as little clearance as possible.

6. The pipe needs to be secured to the side of the barrel is such a manner as to allow incoming air to sweep around the inside perimeter of the barrel (see Fig. 1) and the end of the pipe that is in the barrel will need a rather steep angle cut on it (I used about a 75 degree angle here). Cut the pipe long enough to extend about 3" outside the barrel and all the way inside the barrel so that it comes in contact with the opposite wall of the canister (see Fig 1).

7. Cut a piece of 2 x 2 to the same radius as the inside of your barrel and about as long as the piece of pipe is inside the barrel (see Fig. 3). Now, using a core box bit in your router, make some progressive passes through the center of the 2 x 2, working outward, to allow the pipe to rest into the cove you just created in the 2 x 2.

8. Stick the pipe through the elliptical hole of the barrel. Apply glue to the curved edge of the 2 x 2 and rest the pipe into it's cove on the other edge. Hold the 2 x 2 against the barrel so that it is level and screw through the barrel into the 2 x 2. Then, screw though the pipe at the angle end to secure the pipe to the 2 x 2.

9. Take a piece of neoprene weather stripping and use CNA to glue the stripping around the INSIDE perimeter of the intake pipe and the barrel. Take care to use a dowel to press the stripping against the barrel when the glue is applied, lest it'll leak through to your fingers. Apply caulk on the outside of the barrel around the pipe and allow it to cure. attach the lid to the drum. A sight glass can be applied if you desire but I didn't bother.

The pipe coming up from out of the floor originates 48' away at the other end of the shop and is made up of 2" PVC pipe - there is no grounding wire. Regardless of what you may read, your chances of winning the lottery are vastly superior to having your home shop vacuum system exploding from static electricity.

All of the joints are NOT glued because you don't need to glue them. If you use any "Tee's" in your system, be sure to use sanitary Tee's because they have a little sweep going in the direction of flow - this prevents a blockage in the line.  If you use any 90 degree elbows, be sure to use a sweep elbow - they have a greater radius than regular Ell's - again to eliminate blockage - you can see both of these PVC fittings in the above picture.