I have a dream... a vacuum workbench

[flair woodworks]

I regularly use live-edge materials that cannot be secured from their edges without causing damage.  Usually I resort to surface clamping, but they get in the way of working on the top surface.

Here's an example of some weird stuff I want to be able to hold.

I'm in the process of thinking through the idea of building a bench with vacuum clamping capabilities, but I'm stuck at how to make it:
1) accomodate non-flat work pieces (think rough, rough-sawn lumber); and
2) hold the work securely enough for hand planing.

From my understanding, the Venturi principle requires a seal.  The (Festo!) Bernoulli gripper (check out the 1:00 mark of this video ) does not require a seal (and actually needs somewhere for the air to escape.  But I don't know if I can practically create a Bernoulli gripper bench that will resist hand planing forces.

I've found a few interesting sources/references for vacuum clamping parts, but am unconvinced that they will work with less-than-flat and porous materials:
1) Vacuum Clamp from Lee Valley
2) Podz Vacuum Clamping Jigs
3) Festool Vacuum Clamping System (YouTube video)

 

[tbellemare]

I may have at lest a partial solution for you, Chris...

I just started making some video today and should have some ready for consumption very soon.

It really depends on how irregular the surface but what I have in mind should handle pretty rough stuff.

Tom

 

[flair woodworks]

I look forward to it!

 

[tjbnwi]

3M VHB. Cheep hot glue gun.

Tom

 

[flair woodworks]

Wow, Tom.  I didn't know that tapes that are "a proven alternative to screws, rivets, welds and other mechanical fasteners" existed!  However, they're also described as permanent, and I don't particularly want to resaw the material off my workbench (I've had to resaw templates off my stock before using turner's tape).

I don't think a hot glue gun would provide enough strength to hand plane.

 

[tjbnwi]

To separate the parts I VHB to my bench, I use a 6" broad knife that I sheer the tape with the blade. Drive it between the bench and work piece.

You don't need tape all over, just here and there.

3M also makes 2 sided mounting tape, thicker, not as tenacious.

I use hot glue all the time, you'd be surprised. Use a cheep hot glue and gun. The hi-tech construction hot glues will not be your friend.

If you knew some of the things that are glued/taped together it would scare most. How about some vehicle frames and uni body shells?

Tom

 

[boost13]

I have the vac-sys and it wont "vacuum clamp" onto not flat and relatively smooth surfaces.

 

[tjbnwi]

Chris,

The other thing to consider is how porous (it appears porous in the photos) the wood you're working with is. If atmosphere can pass through the prices with little resistance there will not be enough force to hold the piece in place.

Tom

 

[tbellemare]

The question of porosity of the work piece all depends on how much the pump is moving.

A wind tunnel can be used to simulate water...

Tom

 

[flair woodworks]

To separate the parts I VHB to my bench, I use a 6" broad knife that I sheer the tape with the blade. Drive it between the bench and work piece.

You don't need tape all over, just here and there.

3M also makes 2 sided mounting tape, thicker, not as tenacious.

I use hot glue all the time, you'd be surprised. Use a cheep hot glue and gun. The hi-tech construction hot glues will not be your friend.

If you knew some of the things that are glued/taped together it would scare most. How about some vehicle frames and uni body shells?

Tom

At first, I thought that it sounded crazy.  I still think it does, but I've been known to try some pretty far out ideas so I will keep this in mind.  However, I think that this is more of an answer to the exception and not something I would want to employ for every work piece.

 

[flair woodworks]

In my research, I have come across various shapes and materials from which vacuum suction cups are made.

The standard shape, as seen in the middle of the above image, is available in different depths.  Deeper cups are able to better conform to uneven surfaces.  The accordian-shape cups (termed: bellows) allow flex so they can grip parts not at 90 degrees.

This image just blows my mind:

This seems like a similar application to what I have in mind.  Perhaps this is close to what I want.

The previous two images were from THIS PAGE.

In my research, I also found a video, by some guy named Peter Halle, showing a very simple vacuum clamp.  Perhaps with the right foam (thick and soft?), I could create a decent seal.


Gosh, how do I sleep?

 

[tjbnwi]

I had to domino some small items, easiest way was to hot glue them the a sacrificial board. These were removed with a simple twist.

Tom

 

[tbellemare]

In my research, I have come across various shapes and materials from which vacuum suction cups are made.

The standard shape, as seen in the middle of the above image, is available in different depths.  Deeper cups are able to better conform to uneven surfaces.  The accordian-shape cups (termed: bellows) allow flex so they can grip parts not at 90 degrees.

This image just blows my mind:

This seems like a similar application to what I have in mind.  Perhaps this is close to what I want.

The previous two images were from THIS PAGE.

In my research, I also found a video, by some guy named Peter Halle, showing a very simple vacuum clamp.  Perhaps with the right foam (thick and soft?), I could create a decent seal.


Gosh, how do I sleep?

Schmalz, (one of my vendors), makes vacuum clamping and vacuum material handling solutions for a wide variety of shapes and surfaces. They design and implement custom solutions all over the globe. You have apparently seen some of their work or that of their competitors, Chris.

I have just set up their solution for woodworking and plan to figure out how to adapt it to the plethora of suction pads they offer. They sell a 3 CFM vacuum pump to run the suction pads that go with their normal solution for woodworking (Multi-Clamp). I have a vacuum pump that pulls 8 CFM and plan to experiment with it.

Tom