Anybody try a Vacuum hold down sled?

[spalted]

I'm sure it's a long shot, but have any of you tried or are currently using a vacuum hold down sled?

I have a Gast 3/4 hp 8 cfm vac pump that I've used for various other shop shenanigans and I keep eyeing is for use on the Carvewright as well.
I occasionally have wanted to run some things that were difficult or impossible to fixture in a normal sled.
Thin sheets of plastic, or thin wood, and assorted foams come to mind.
I think the Carvewright makes such light passes that I could even hold small pieces of wood with vacuum without breaking the vac seal too, if needed. I know it would hold large pieces, but I can see a need for that in this application.

I have some half formed ideas, but I wanted to check and see if anyone else had experimented with it at all?

[Mugsowner]

I have thought about it as well, but never gave it a try. Thought it may work as they use vacuum on the larger table routers.

[Digitalwoodshop]

I bought a bunch of the mushroom shaped wood plugs in 3/8. My plan was to have the machine drill a bunch of 3/8 holes on a carrier board and fill the holes with the plugs. Then fit a shoulder and insert a hardboard. This mushroom head thing would give me a chamber to tie a vacuum pump to with a hose. I would design a project on the sled and select places to drill holes to hold future parts on a board laying on top of the hardboard with holes in it. I would have different hardboard hole inserts for different projects. I would use it to hold down the plastic tags I cut from sheet stock. I use double stick tape now. This has been in planning for many years.... Just have not gotten to it... Taking this Retirement way too serious.... :)

[Mugsowner]

I like that idea. The insert would be awesome. Carve it up, toss in a new one.

[spalted]

The changeable soil board type insert setup was all I could think of too.
Digitalwoodshop I like your idea for creating the vac chamber.
I was thinking on machining a vac plate style grid that a sacrificial soil board could be put on, and bore vac ports in the required locations.

On big routers without a flat bed there are movable rails with movable vacuum pods on them.
Then you can position your vacuum points to avoid cuts and holes.
That setup only works for solid stock or some panel cutting.

I don't have much experience with the big flat bed styles.

I don't really have a lot of uses for one yet, but I've never let that stop me before.

[tackytim]

I bought a device that uses compressed air to create the vacuum. It's really designed for auto AC systems, but it'll pull almost 2 atmospheres of vacuum. I got it from harbor freight. I think 20 or 30 bucks. I cant remember how many cfms of air it takes, but it uses standard air fittings. I think it could be easily adapted to use for a vac table in lieu of a dedicated pump. I'll look at it when I get home.

[Mugsowner]

I have seen those pumps also at HF and do feel they would work. I have a few vacuum generators that also use air to produce the vacuum. It have been a plan of mine for a time now to make up a vacuum table and sled. With quick change fittings I could just move the vacuum source back and forth between the fixtures.

[spalted]

I have seen those pumps also at HF and do feel they would work. I have a few vacuum generators that also use air to produce the vacuum. It have been a plan of mine for a time now to make up a vacuum table and sled. With quick change fittings I could just move the vacuum source back and forth between the fixtures.

I plan to use press to connect, or press-loc style fittings if I build one.
I use them at work for building vacuum fixtures and for vac circuits all the time and they work really well.
Here is an example of a couple different styles, but there are thousands of choices.
https://www.automationdirect.com/images/overviews/nitra_special_valves_300.jpg

[Mugsowner]

That is the style fitting I would use as well. We use them to run the pneumatic systems on the machines we build. They hold and seal very well and allow for quick change capability.

[cestout]

Seems to me it would suck up a bunch of saw flour.
Clint

[spalted]

Seems to me it would suck up a bunch of saw flour.
Clint

Set up right you don't suck up much dust.
In a typical vac hold down system you either plug the unused ports or some have a little valve that pops up unless there is a piece of wood on them, which prevent dust from entering your vac system.
There is a filter before the pump to catch any that does make it through though.

I really want to try this, but I haven't had time to design it yet say nothing of build one.