Vector table works suprisingly well

[Frédéric PARROT]

Hi Keith,

Thanks for the pictures.

I think in my case the clearance under the material to be cut is not large enough.
I cut paper or cardboard and colored smoke stains often the back of my cutting table despite the honeycomb.
The ULS-PIN TABLE KIT is very expensive so I think I'll try the solution with the golf tees indicated by Dan.

[Keith Outten]

Fred,

When I made the first Corian table I was concerned about the height of the prisms and whether I would be able to push enough air under the plastic. As it turns out the table performs well but it requires a bit more air than a standard fan. Since I use a dust collector attached to my laser engraver I have plenty of air and the flow under the material is better than my standard aluminum honeycomb table because the air comes in contact with the bottom of the plastic when I use the Corian table much the same as the golf tee system works.

The new Corian table has more depth, the prisms are taller because I used a 60 degree bit so the performance is even better than the first table. Although I haven't measured them the new table prisms are about 1/4" deep, the downside is that they are very sharp so the table is best handled by the frame. The supports on the bottom keep the table flat and provide space for tape to wrap around the edge to secure the plastic to the table and keep it flat when vector cutting.
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[Dan Hintz]

Although I haven't measured them the new table prisms are about 1/4" deep, the downside is that they are very sharp so the table is best handled by the frame.

A quick pass with a belt sander, maybe? Faster than trying to knock the tips off using the CNC, though the CNC would ensure it remains level.

[Mark Ross]

Keith,

We cut a ton of 1/8 to 1/2 inch acrylic (8-10 hours a day). Are you saying we could lay the material right on the corian and vector cut through it? Wouldn't the corian get damaged in the areas we do the cuts in? Thanks for your reply. I never thought of doing it this way. I'll post a picture of the last attempt we did using bolts when I get a chance.

We also cut a ton of plastic (styrene) that is 1/16 of an inch thick and that stuff is gummy, sticky, you cant clean an aluminum vector grid without destroying it and to boot, the residue loves to catch on fire. If this would work and we could power wash it, that would be awesome.

[Mike Lysov]

I have a similar "bed of nails" that I use for larger pieces but found it a pain for smaller cutouts. If the pieces can fall down the way many of your circles have done, they all too often seem to land where the beam cutting a neighboring piece makes an out-of-focus burn across the dropped piece. One particularly unlucky batch of approximately 1" shapes had more than 1 in 4 ruined that way... but making a large BON with less than 1" spacing is a time consuming PITA. Now I tend to use a honeycomb with a few scrap L shapes of 1/8" ply at the corners and a narrow scrap ply strip or two near the middle as spacers to raise the work piece and prevent any back burn or melt from the honeycomb.

-Glen

the pin or nail raised cutting works great but it's really a pain for small and sometimes for big cutouts. The solution is simple. You do not need these pins/nails to raise material too high. 2-3mm is more than enough to get rid of reflection at the back of material. I have found that using a honeycomb table with short pins that raise material above it just 1-3 mm leaves no much space for the cutouts to fall down under to be hit by the laser beam.

It's better to be used with the honeycomb because this way there will be a lot of airflow through honeycomb cells for fumes extraction.

[Keith Outten]

Keith,

We cut a ton of 1/8 to 1/2 inch acrylic (8-10 hours a day). Are you saying we could lay the material right on the corian and vector cut through it? Wouldn't the corian get damaged in the areas we do the cuts in? Thanks for your reply. I never thought of doing it this way. I'll post a picture of the last attempt we did using bolts when I get a chance.

We also cut a ton of plastic (styrene) that is 1/16 of an inch thick and that stuff is gummy, sticky, you cant clean an aluminum vector grid without destroying it and to boot, the residue loves to catch on fire. If this would work and we could power wash it, that would be awesome.

Ross,

Yes, you can vector cut all day long using a Corian table. The last time I cut letters and numbers for ADA signs I spent ten days cutting 8 hours per day on our Corian table. There is a small amount of damage to the Corian prisms but it should last for many many years before it has to be replaced. Pressure washing is a great way to clean Corian, you can even soak it in a degreaser for awhile before you power wash it if you need to.

[Stephen Sullivan]

Keith, thanks for the photos!!

[Frédéric PARROT]

Keith,
Very thanks for the explanations :-)

[Ian Wilson (AUST)]

Hi Keith,

Could I pls see your pictures?

Thanks Ian

[Sandy Henry]

Keith, What is the purpose of the support pieces. Why not lay the 1/2" sheet directly on laser bed? Thanks, Sandy

[Keith Outten]

Sandy,

If you look closely you can see that I glued two pieces of half inch thick Corian together to make the table surface. I did this because a single sheet tends to warp a little bit when you machine so much of the surface away. The supports on the bottom help to keep the table perfectly flat and they lift the vector table off of the engraving table so it is easy to install and remove. The additional height that the supports provide also makes it easy to tape thin engravers plastic around the edge to hold it flat.

The reason that I leave the sharp points on the prisms is that the table needs to be perfectly flat if you want to engrave materials like laser lights or AlumaMark. There is just enough space for air to move under the material to be engraved or cut and there is plenty of support under the material to keep it in place. Another nice thing about this design is that small pieces that I vector cut don't drop down inside the table so it is easy to place a piece of matte board on top of the vector table and flip it over to unload hundreds of letters and numbers when we cut them for ADA signs.

Ian, my pictures are attached to post number 14.
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[Albert Nix]

May have to try that Keith..Thanks

[Sandy Henry]

Thanks Keith, This will keep me from scrapping my 1st attempt at making one of these. Do you glue the 2 1/2" pieces together before or after milling? Thanks Again!

[Ken Dolph]

Keith,

Two things will keep the cupping down when doing machining in Corian.

First keep your feed rate down 30 to 60 ipm. This lessens the uneven heating from friction.

Start in the center of the material and spiral out. This balances the heat build up. Since Corian anneals with heat it will be slightly smaller after heating and cooling. This is the most common cause of cupping.

I know that both of these suggestions will slow down the processing but sometimes it is worth it.

[Keith Outten]

Sandy,

Yes, I glue the two half inch sheets together before I machine the prisms. Make sure you have a good flat table or you can use to keep both pieces flat while the glue dries.
I cut the two pieces just a little oversize so I can machine them to size on my CNC Router, in this case 12" by 24".

Ken, thanks for the tip. I always machine Corian at a slow speed (routing or sawing) based on your recommendations a long time ago. The CNC machining doesn't produce any measurable heat to the best of my knowledge.
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