If you still needed 6mm mesh you might try

http://mnpctech.com/case-mods-gaming-pc-liquid-modding-custom-computer-mnpctech-overclock-cooling-fan-grills/modders-mesh-honeycomb.html

I agree you'd want something with a larger cell size if you're building a whole table.  

There are aluminium honeycomb cores (generally used in composite panels) available from 

www.mcmaster.com/#aluminum-honeycomb-matrix/  they have various sizes and getting the cell size for the core models might require a phone call.

there are also honeycomb flourescent light louvres usually used in recessed fixtures.

http://www.goodmart.com/products/louvers-intl-para-image-vi-hexagonal-parabolic-louver-2-x-4-gold-ceiling-style-styrene-3-4-x-3-4-x-1-2-in-li-6-24-gl.htm

I'm sure looking around will find something cheaper/more suited to your application, but anywhere that caters to commercial construction or carries recessed flourescent fixtures is a good bet to start. 

there are tons of honeycomb composite panels that you can pull apart but where to look depends on where you are,  

http://www.plascore.com/products/honeycomb-cores/thermoplastic/   Is an example of the types out there.They don't look like a sell to the public kinda outfit, but looks decieve.  They make honeycomb mesh to space tiles and support granite as well.  if I knew your location i could probably track some options down, I know where i would buy in my part of canada.  b

It's very easy design an print in a 3dprinter the exactly form and size grid you need

It's very easy design an print in a 3dprinter the exactly form and size grid you need

Unfortunately I don't have access to a working 3D printer at the moment.

The local hackerspace has a RepRap but AFAIK that one doesn't really do what it's supposed to do.

http://www.easycomposites.co.uk/products/core-materials/19mm-aluminium-honeycomb.aspx

.. or as I said, make your own, fold a bunch of long strips of material at say 1 cm intervals,  glue every 4th interval to the 4th interval of the strip below. Glue pairs of strips together to make hexagons. Contune to glue on extra pairs ad infinitum.

I thought there might be a good commercial solution out there but I think I will fold my own as you have suggested! 

Thanks!

http://www.ebay.co.uk/itm/10-sheets-A2-420x594mm-fluted-plastic-corex-board-for-outdoor-sign-age-display-/150815924694?pt=LH_DefaultDomain_3&var=&hash=item231d5461d6 

Use it like corrgated cardboard, sandwich as many layers as you need, shine the lights up the corrgations. Not hexagonal exactly, but it might do the trick. 

Failing that, make your own hexagonal corrgated sheets, a little precision scoring, folding and gluing of plastic sheeting should do the trick.

From http://www.ebay.co.uk/bhp/plastic-mesh :

http://www.ebay.co.uk/itm/1m-x1m-BLACK-SEMI-RIGID-HDPE-5mm-STRONG-PLASTIC-HD-MESH-SCREEN-FISH-GUTTER-GUARD-/291288194667

Looks like it might be the right size, but seems like maybe not the right form-factor.

Hows this? (googled "plastic hexagon grid")

http://www.alibaba.com/product-detail/Plastic-Grass-Paving-Grid-with-hexagonal_1345073558.html
Good enough?

Thanks for the quick reply!

I have found those for gardening but to be honest those are still too big.

Another thing I have found are hexagonal grids for car tuning but those aren't regular hexagons.

Went trough google a bit more, learned that beehive hexi's are on average 5.5mm large.
Tried to find some product, but no luck :(

So, instead, you will have to make something, the below could be of help, but know that theres alot of work involved:

http://www.wikihow.com/Construct-a-Hex-Board
[1] When you reach step 3, make the circle diameter 6mm

[2] When you reach step 11, your done drawing stuff

[3] After step 11, measure the length of 1 side of one of the hexi's

[4] Go to your favorite local store and pick up some sheets of plastic or thin wood, cut it in strips

[5] Cut out little notches halfway into the strips, spaced apart the distance you measured in [3]

[6] Stick the strips together till you get a grid of triangles

[7] Glue everything together

[8] Cut out walls (of the triangles) till you get a hex grid.

Like i said, quite some work :P but that doesn't mean its impossible, just be prepared to spend an afternoon/day

But realistically, you should really just consider going for a bigger grid to save yourself some trouble, also because you may not fully realize that a small table of 60 by 60 cm would already require well over a 1000 leds if your hexagons would be the size you want (beehive size)
Not saying that wouldnt look super awesome (and open the door to all kinds of games on it) ofc, but yea, you may wanna rethink this a bit to increase feasibility and lower the costs.

That's a great tutorial there! I am aware that making my own would be a lot of work and you're right, going for 5.5mm hexagons for a reasonably sized table wouldn't be very feasible. 

I think I will drive down to the hardware store and have a look at what kind of gardening hexas they have, maybe there's a reasonable size available.

I really appreciate the help, thanks!

Elia

My pleasure, love the idea. :)

Actually been playing with a similar idea myself, but as a wall piece with ~3cm cubes or hexagons, where kids can press the blocks to make them change color, and it would start scrolling when there's no interaction for a minute or so. But that's still a long ways away (because i need to come up with some things like how to make a nice grid of cubes/hexis with buttons behind them and rgb leds inside, and im super lazy hehe, i hardly 'hack', just come up with ideas)