PDA

View Full Version : Vector Table Honeycomb Material?



Jeff Lehman
05-23-2007, 9:53 AM
I am looking for a vendor of fire-retardant paper honeycomb material 1" thick approx 50" x 97". The laser is primarily used to cut veneer, so flashback is a concern so a aluminum material would not be suitable.

Any recommendations would be greatly appreciated!

Joe Pelonio
05-23-2007, 10:27 AM
Fire retardant or not it seems like paper wouldn't last long. Have you thought about using the plastic stuff used for flourescent light fixtures, like in the dentist's office?

Brian Robison
05-23-2007, 10:32 AM
Mike Null supplied me with a plastic grid, I got it yesterday. I tried it last night for cutting acrylic mirrors.
So far it works great. I haven't had a chance to let Mike know yet. HEY MIKE, IT WORKED! Sorry for the yelling,
I wasn't sure if Mike could hear me from here.;)

Jeff Lehman
05-23-2007, 10:49 AM
The material we've been using is impregnated with something that greatly reduces the burning. With 40+ hours a week of cutting a sheet can easily last 4-6 months (200 watts). I've found a honeycomb material on the net that is made of NOMEX, which I've been told is impregnated with a phenolic resin.

Still on the lookout though...

Rob Bosworth
05-23-2007, 10:59 AM
Hey Jeff, I think we used to buy it through Tri Cell Honeycomb or through Hexcell. That stuff works fabulous, even though it can get a little sooty after a while. Good luck.

Belinda Williamson
05-23-2007, 11:22 AM
Have you checked out Plascore? This may be what you are looking for.

Mike Null
05-23-2007, 12:28 PM
First let me thank Brian for the commercial. (I actually wanted him to test the material and give me a private report but this is nice)

The material Brian is testing is acrylic and the reason we're not marketing it yet is we don't know how long it will last. We do know that the laser will degrade it but if it provides a reasonable life that's ok.

I am in the process of testing a nomex honeycomb but what I've seen so far leads me to believe that this material will degrade too fast and that the cells are too small and therefore trap smoke. It is also relatively expensive.

Craig Hogarth
05-23-2007, 1:39 PM
Can somebody give me a lesson on how the honeycomb material affects various materials? I bought one through ULS. Is there a disadvantage to that? I figured they were all the same.

Ed Lang
05-23-2007, 2:20 PM
Craig,


I too have the Universal Laser Systems vector table. Ours is a box that connects to the exhause port by way of the rectangle in the rear that you removed the cover plate from. You did remove the cover plate right? Ours will draw air down past the lasers curf while cutting. Some of the other will not. They are just static and hold the parts above the metal table.

Craig Hogarth
05-23-2007, 2:34 PM
I don't know if the cover is removed, but I can see the smoke leave when doing acrylic. I'll have to check when I get home. Thanks

Mike Null
05-23-2007, 3:14 PM
Ed's point is well taken. Most of the honeycomb grids have very small cells which do not always allow the smoke to be evacuated. These are generally the ones sold by the laser manufacturers.

A few of them have an integrated exhaust system but most do not.

Another down side to the honeycomb with the small cells is that objects (waste, small pieces, parts etc.) sometimes become lodged in the grid.

The larger cells are almost always superior in terms of smoke and residue evacuation as they provide an unrestricted path for the air to flow as compared to the usual honeycomb grid. They are much less expensive but they come without a frame.

Mark Winlund
05-23-2007, 6:28 PM
Craig,


I too have the Universal Laser Systems vector table. Ours is a box that connects to the exhause port by way of the rectangle in the rear that you removed the cover plate from. You did remove the cover plate right? Ours will draw air down past the lasers curf while cutting. Some of the other will not. They are just static and hold the parts above the metal table.



If your exhaust system is strong enough, It will also hold many materials flat if you mask off the remaining areas.

Another point: Use a piece of aluminum window screen on top of the honeycomb... it will catch all of the tiny pieces. You can also lift the whole works out of the laser after it is cut.

Mark

Ed Lang
05-23-2007, 8:44 PM
I use a Delta single bag dust collector with the bag removed and the unit is outside of the shop. The input of the collector is piped in the wall with a blast gate to stop cold air and other "critters" from finding a way inside at night. I hate snakes!

I like the idea of the screen, I'll try that.

I would also like to find a cheap material that I can replace my metal, small hole grid with soon. I can remove a few screws that hold the rulers around the gird and replace it. I have not found the plastic light fixture grids at Lowes but will try Home Depot on Saturday and hope for the best. I think soaking mine in Greased Lightning cleaner is what keeps the back of my projects nice and clean. When the residue starts to build up on the grid, I noticed the smoke on the back side of everything.

Rob Bosworth
05-24-2007, 1:18 PM
Ed, I have played with different materials to use as a vector grid for years. One of my brainstorms, which are getting fewer and fewer, I boght a bunch fo different light grid diffuser panels from one of the big box home improvement stores. Most of them put off clouds of black smoke and charred up pretty quick. Maybe one pass, and the next part got so sooted up, you would have to flip the diffuser panel. Yuck. It usually left a big black smudge of soot on the bottom side of the lens.

The reason some people do not like to use metal as the support material in their vector cutting tables is the reflection of the laser beam off the metal honeycomb or metal grid, flashes the underside of the part that they are cutting. Plastics that are really heat sensitive will show every one of those flashes.

I would guess the reason Jeff is looking for replacment fire retardent paper honeycomb is the material he is running shows a lot of flash marks on it. Fewer flash marks on the back side of what you are cutting, and cleanup is much easier. Also, LMI* use to use the paper honeycomb. It works really well for support, minimal flashback, and you could get it in a number of different cell sizes. Sure it charred up after a while, but then you just flipped it over and used the other side. When it was done, and you knew when it was done, you just throw it out and put in a new piece.

*LMI - Laser Machining Inc. was a pioneer in the laser engraving systems field. Now called Preeco and no longer makes laser engraving systems.

(I'm getting so good with trying to explain things, that my next posting will probably have to have a bibliography as an attachment.)

Dean Flannery
05-24-2007, 2:11 PM
McMaster Carr (www.mcmaster.com) sells a nice aluminum honeycomb up to 1" thick, I made my vector table with it and the honeycombs are so thin I have never had a flashback problem. At their website type honeycomb in the search box and it will pop right up.

Dean

Dave Rawn
05-25-2007, 2:07 PM
you can check with Kern Electronics and Lasers, INC. www.kernlasers.com (http://www.kernlasers.com) they have the material that you are looking for. I tried it and it works very good :)

Lee DeRaud
05-25-2007, 3:03 PM
The reason some people do not like to use metal as the support material in their vector cutting tables is the reflection of the laser beam off the metal honeycomb or metal grid, flashes the underside of the part that they are cutting.Reading that, the first thing that jumps into my head is, does anybody sell black anodized aluminum honeycomb? For that matter, has anyone tried painting the regular honeycomb with black high-temp engine paint?

Dave Jones
05-25-2007, 5:34 PM
When a laser hits black anodized aluminum it will bleach the dye and turn it white (or light gray). A laser will blast black paint or powder coat away. They are often used on items that are engraved, where that coating gets engraved away.

Lee DeRaud
05-25-2007, 5:40 PM
When a laser hits black anodized aluminum it will bleach the dye and turn it white (or light gray).Hmmm...if the white/light-gray is less reflective than bare aluminum, doesn't it still help eliminate flashback?

Dave Jones
05-25-2007, 6:02 PM
I think the key would be to have the thinnest, sharpest possible edge touching the material, giving the least amount of surface to reflect anything back. I suspect a paper thin stainless steel would work better since it's hard to have aluminum with as sharp an edge.

In theory, I would think a grid of razor blades might be the ideal surface, but I could see some real drawbacks to that too. :eek:

Mike Null
05-25-2007, 8:55 PM
Just a little too much power will take you right to bare metal. I've looked into your concept and decided not to pursue because of what I perceived to be a short life of the coating.