Ideas for adding router vaccum/cutting surface on top of water table

[motoguy]

Looking for ideas on adding a router surface to my plasma table. I've got the router mount and router, but I've never cut anything on the table. The stopping point for me has been the slats and slag build up.

After cutting with plasma we get slag build up on our slats. This means the slats are never (or rarely) level across the top. While fine for the plasma process, this (IMO) would not work for routing, where material that isn't completely square to the end mill would show steps and angularity.

My table is a 6x12 unit with water table. The water pan is welded to the table frame, and is not removable. As such, I need a method that does not involve "slide off the pan, and slide on your router table top". If I had 1) a removable pan, 2) a larger work area, and 3) a forklift capable of swapping work surfaces, this would be a great idea. But, I don't.

As the router surface would have to be clear of the slats and slag, I'm trying to come up with a system that would mount to the table edges, and elevate the router surface slighly above the slats. Say, 1/4" or so. Just enough to NOT contact any slats or dross.

I've thought about using angle iron across the table, with clamps to clamp the edges of the water table. Then place my (thin) vacuum box over these cross braces. I have 8" between the top of the water table and the gantry, so I have a bit of space to use. I'm not sure what design would span 6' without central supports, and still be solid enough to hold a routing surface.

Right now I'm just brainstorming, and trying to come up with a way to support a thin vacuum box across my existing table, while being able to actually level it. Any thoughts or ideas out there?

Here are photos of my table design, and the type of router vacuum box I'd like to create/attach.

routing box.jpg

starlab1.jpg

[_Ogre]

pull a couple slats out and run a 2x4 across the table with maybe a shim under the center slat support to reduce sag, then throw a piece of 3/4 plywood across the 2x4s. we have a bulltear 4x8 table and have many fixtures on the table that are 5 inches tall. we take full advantage of the free air under the gantry. i'd think you'd want the whole table covered or you'll get a table full of soggy sawdust.

[Granite]

When I bought my table it was setup for both plasma and routing. No vacum, just a 3/4" spoil board that sat directly on top of the slats.

Like you have alluded to, dross on the slats, lead to problems. My fix was basically what you are already thinking. Used 1"x 1"x 1/4" angle iron, 2 feet on center. (For my 48 x 48 table I needed three angles)

You can see how I notched the angle to rest on top of the table frame. Then I drilled and tapped the frame to keep the angle secure. Once the angles are installed, the four corners of the spoil board are clamped to the angles. (The clamps can interfere with router movement on large jobs, so bolts would be better)

The spoil board clears the slats by about 3/8".

One of the images shows how I stow the torch when routing. (Two ty-raps used each time I make the switch)

It all works very well for my home based shop. I have to remove two slats when converting from plasma to routing. (After you do it several times, the switch over takes just a few minutes.) As much as I try to plan my jobs, sometimes I end up switching between plasma and routing a couple of times a day. I do mostly sign work, this configuration works well for me.

Here are my steps: (Plasma to Router)

-- Remove torch and stow
-- Mount router
-- Remove two slats
-- Install three angles
-- Place the spoil board
-- Clamp board to angles

It looks like your slats are higher than your table frame. You could add a spacer plate to get your angles high enough for clearance.

[Granite]

Motoguy, I read your post again, maybe try 2" x 2" x 3/8" angle to make the 6 foot span? The vacum box in your pic looks like its about 48" x 48"? Ogre mentioned saw dust in your water. Yes, I just live with that. With a vacum, I'd think you wouldn't have much of a problem.

[tylerd]

Convert to downdraft

[steel 35]

Granite; Thanks for sharing I may give that a try.

[motoguy]

Granite, thanks for the idea! I don't have the horizontal bolt surface on the side of my table like you do, but I could weld some angle (either full length, or just the areas needed) to provide the mount surface. Then I could basically mount as you do. Maybe add an adjustable leg mid-span to avoid sag. I wanted to avoid digging around in the muck at the bottom, but a small footprint leg wouldn't be that big a deal. That would let me rough-level the angle, anyway.

Curious, do you surface your plate every time? Or for what you do, is an absolute square surface not a big deal?

[Granite]

Before I added the angle cross braces I was fighting a loosing battle using a large planer bit to keep the surface flat.

Now with the 3 angles, my 3/4" spoil board is flat and solid. I've not used the planer bit since the upgrade.

Most of my use is v-carve lettering and 3d logos. I index a lot of 4' x 8' x 3/4" substrates for larger signs and its spot on. I indexed the profile cuts on the panels for this 2" thick two-sided sign. Then a ball nose to carve the 3d horse logo attached to both sides. This entire job was cut on the 48" x 48" x 3/4" mdf spoil board. (no planing or leveling)

If it were me, I'd try the 6 foot span with some stout angle and see how it does.