Suction table on mini Helix

[Craig Matheny]

Ok I have some semi bowed 12x24 3mm B/BB Baltic birch Plywood grain is front to back the 12" length not the 24". The bow is maybe 1/4" at best in the middle so in theory with the suction table it should be able to flatten it out. I have a HB 1hp green blower 4" metal ducting 23 flex connectors even unhooking from the blower exhaust hardly any suction. So I have blocked off some of the top air vents to try and force more suction from below still not doing the job. Any ideas?

[Tony Lenkic]

How about misting the ply with some water than sandwich it between couple of boards adding some weight and leave it for few hours to flatten out.

[Joe Pelonio]

Apply pieces of 3m VHB or equivalent double sided tape to hold it flat to the bed. Just be sure to use it in places all over the material so it’s all the same distance from the head to remain in focus.

[Glen Monaghan]

I've frequently just applied a bit of blue painter's tape at the high point(s), either taping to the rulers (back/top, left and right sides), or to the side of the table (front/bottom side). It is easiest to do when the middle bows up because you only have to tape the back and maybe front middles (when the piece bows down in the middle, you have to tape on both left and right, usually in all four corners).

Depending on what you are doing, you also might be able to use flat steel bars or lead weights strategically placed on the top of the BB to press it down.

[Craig Matheny]

Thanks guys for the ideas, the only problem I am cutting over 10k 12 x 24 sheets and 25% are bowed. So I was hoping for the miracle fix.. Oh well THanks again

[Kev Williams]

Assuming your table isn't aluminum, get a bunch of as-large-as-you-can-use, very strong magnets, and place them where the laser won't be cutting. I cannibalized about 20 magnetic badge clasps and use the magnet strips as helpers all the time- because they're 2 aggressive magnets glued to a small metal strip, they hold great, and the strip is off the table enough to pry them off the work easily-

For my GCC and LS900 which have aluminum tables, I picked up a couple of 18" x 24" x .030" thick white steel signs from Regional Supply, they're very flat and work well as magnetic backers :)