Dust Collection - Table Saw and Router Table #2: Vacuum Valve

  • Advertise with us
Blog entry by EEngineer posted 11-09-2013 05:02 PM 3582 reads 0 times favorited 1 comment Add to Favorites Watch
« Part 1: Dust Separator Part 2 of Dust Collection - Table Saw and Router Table series Part 3: Control Box »

Whew! It has been a while since I added anything to this. But it took a while to get this part right. I needed a way to steer the vacuum from the shopvac and Dust Deputy to either the table saw or the router table. Inspiration for this design came from here .

In principle the valve is pretty simple:

Just a flapper moved by a rotating shaft to steer the vacuum to one port and seal the other port off. To move the shaft I borrowed the design from the seed link above. I ordered a couple of 120 VAC solenoids and mocked the driver up on my bench to see how it worked. A scrap piece of MDF, two plugs from a hole saw leftover from another project and lots of rooting around in the junk box:

These tests went really well. This solenoid has some authority! The seller rated it at 3 lbs of force and I believe it. I made up all the pieces for the entire valve:

And here is the solenoid driver with shaft in its new home:

When finished there will be a 2” cavity for the solenoid and moving parts. This will get a cover to keep fingers out of the moving parts and away from the hot solenoid. This solenoid is rated for continuous duty but, when I left it activated for 20 minutes, it did get hot.

I made a quick jig to remove part of the shaft to hold the flapper at the router table. There must be a better way to do this! I ended up making 3 shafts to get one good one. The shaft kept tearing out at both ends of the cut.

And here is the flapper, simply a piece of 3/16 plywood, installed:

I epoxied weather stripping onto the flapper to get better seal:

Getting a good seal on both ends of the flapper was the hardest part of this project. When I drilled the holes for the shaft, I centered it in the valve cavity. When I made the flat for the flapper to attach to the shaft I felt that centering the flapper in the shaft would weaken the shaft too much. So the flapper ended up offset from the centerline of the shaft by quite a bit. I should have offset the holes for the shaft to compensate for this.

In the end, I used a round nose router bit and routed two channels in one side of the cavity to compensate for the flapper offset.

I epoxied pieces of 2 inch PVC pipe for connection to standard 2 1/2 inch vacuum hose:

In the picture above, you can see the relief I routed to compensate for the flapper offset.

And here is the completed valve:

Next up: the Control Box.

-- "Find out what you cannot do and then go do it!"

1 comment so far

View Craftsman on the lake's profile

Craftsman on the lake

3332 posts in 4207 days

#1 posted 11-09-2013 08:07 PM

Okay, I’m impressed. Can’t wait to see it up and running.

-- The smell of wood, coffee in the cup, the wife let's me do my thing, the lake is peaceful.

Have your say...

You must be signed in to post the comments.

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