Downdraft Table

Intro: Downdraft Table

Two things can be a real hassle when sanding. One is holding the work-piece and the other is the dust. This simple downdraft table hooks up to your vacuum cleaner to solve both problems.

STEP 1: Tools and Materials

Tools

• Circular saw or table saw
• Coping saw or jigsaw
• Framing square
• Clamps
• Pencil
• Center punch
• Drill and bits

Materials

• ¾" MDF

• ¼" plywood

• Glue
• Vacuum hose coupler

STEP 2: Lay Out and Drill a Grid

I use an old printer cabinet as a wood working layout table. It has a pocket in it where the printer used to sit. This will make a perfect place for the downdraft table. For yours, consider just building a box using the same technique.

Start with the MDF. Lay out a grid on it and drill it. This one has a grid of 10 x 13 for 130 ¼" holes. It's a good idea to countersink the holes.

STEP 3: Make the Vacuum Chamber

Cut a piece of plywood of appropriate size to cover all the holes in your drilled grid. This is the floor of the vacuum chamber. Also cut strips of plywood wide enough to accept your vacuum hose coupler and appropriate length to attach to the sides of the vacuum chamber. Using a butt joint as shown here will require you to cut these strips to the length of the side PLUS the thickness of the wood you're using. In this case ¼".

You'll notice my sides are not that tall. That's because I'm putting my vacuum coupler on the bottom.

I was only able to find two of my corner clamps, so I could only glue two corners at a time. This turned out to be a blessing in disguise. Glue two corners and let them set up. These will make the sidewalls of the vacuum chamber. Glue the edges of the floor and clamp the walls onto the floor with bar clamps. Apply caulking or construction adhesive to the interior of the joints to make a vacuum seal.

Since this is using ¼" plywood, it's probably a good idea to make a couple of support strips to go in the middle of the floor to keep it from bowing in under heavy vacuum.

STEP 4: Cut a Hole in the Vacuum Chamber

Cut a hole in the vacuum chamber of appropriate size to accept your vacuum hose connector and glue the connector into place with construction adhesive.

STEP 5: Glue It Together and Use It!

Apply a generous amount of construction adhesive to all the mating surfaces of the vacuum chamber and glue it to the MDF top. Set some weights on it or if you prefer, attach a vacuum hose and block the holes to let the vacuum apply the clamping force.

When the glue dries, hook up the vacuum and try sanding something. No more breathing dust and the work piece is held nicely in place.

Comments

[tbearkrue]

Great project! Using flimsy pegboard, couldn't you glue 2 or 3 sheets together to make it sturdier?

[Ag800Hans]

I know, right?! I immediately thought about just gluing 3 sheets of 1/4" pegboard together, & if thats not enough, then apply bracing where need be. I fail to see how that wouldnt work. The 1/4" pegboard that i have, it doesnt seem flimsy - its just a 1/4" wood/paper material, so if its compared to metal sheets, or thicker material, then yes, i would say its flimsy. But ive noticed that if the area/size of the pegboard sheet is relatively small, its pretty strong for being a 1/4". When ive chopped down my 6'x4' sheets into smaller pieces, they're fairly rigid, not easily snapped...

[wood doctor]

Thanks for the inspiration it gives me ideas.

[betser]

Marsh - great instructable, I'm inspired. Thank you!
Dui ni shuo de dui - your pics look great! Could you post the first 9 separately tho? They're too tiny! And would you mind saying more about your piping and locking system?
Thanks to you both!
Betsy

[Dui ni shuo de dui]

Hello Betsy,

The fist 9 little pics are actually some tiny avatars of the big ones, so they are exactly the same. I don't know why my message appeared this way but it seems that it can't be modified once posted.

The piping system is made out of 40mm PVC tubing. It goes under my workbench where I will attach it to a big vacuum system that I'm currently designing.

About the locking system, you can see on the pictures that there is a valve on the pipe. I will open this valve whenever I will want to use the downdraft feature so the air and dirt will be able to pass through, and I will close it whenever I will need to use other vacuum connected devices, such as my bandsaw, drillpress or any other things, which will have their own vacuum hoses with valves too.

I don't have picture of the system I'm talking about since I haven't build it yet, but it will come relatively soon so I'll probably make an instructable about it :)

[ryanjohnlenz]

Great project--one question: what is the purpose of counter-sinking the holes? (other than making it look cool!)

[Marsh]

I only countersink them to take the sharp edge off.

[nbarrow]

It might be to increase surface area of the hole and make the suction a bit stronger?

[WVSundown]

Wow, thanks!!! You just saved me a lot of time and head scratching with this instructable to do the same thing in my workshop. I wonder if this could be used for a spray paint booth, too?

[Marsh]

I would worry that the vacuum may cause an explosion with paint.

[ampersand2006]

This would be awesome for screen printing! They make really expensive tables like this for that purpose.

[mach1950]

Great idea, and perfectly simple. Thank you. :-)

[OutlawKtulu]

You list MDF for the board, but would pegboard work also?

[quas1mod]

I've never seen 3/4" pegboard, the stuff I'm used to seeing would be pretty flimsy.

[DDW_OR]

For Pegboard, put thin supports in the vacuum chamber in a spoke pattern.

this should help spread the Vacuum out to the sides.

[OutlawKtulu]

The stuff I have is 1/4 inch pegboard that I got off a store display that was being thrown out. Didn't want to see all that good pegboard going to waste. :)

[C VB]

You might want to stiffen it with some wooden slats glued onto the backside.

[muadibe]

Thanks for sharing,

I will be having a go at making my own.

[Dui ni shuo de dui]

Very sweet idea, I will try to use that for my workbench !

I think it could also be used to make some thermoformed plastic.

Just have a few questions, how is the succion force at the sides? is there a big difference with the center?

Doesn't the dust accumulates too much inside the box?

[Marsh]

It holds the workpiece down pretty securely and as long as it's dry there shouldn't be any pileup inside the box.