Laser Hold-Downs/Clamps?

[Larry Allred]

I use a lot of 1/8" plywood in my Epilog Helix. Warped stock can be a headache. If it's not too bad, tape and sometimes weights will work. Been toying with some kind of clamps for the bad stuff. The rulers pivot, so tabs on them don't hold. Heavy weights skew the bed. wide tape isn't always strong enough. One guy suggested rare earth magnets but the grids are aluminum.

Anyone use something that works?

[George M. Perzel]

Larry;
I have been dealing with this problem for 10 years and have tried everything imaginable and then some.
Best solution, assuming your laser table (not grid) is aluminum is to get a thin sheet of steel-not stainless-and fasten it too the existing table-use double tape if you don't want to drill holes. Then buy a bunch of 1" rare earth magnets 1/4" diameter. Position them on table as needed and as many as you want. The use i/2" by 1/8" thick rare earth magnets to hold ply down. The magnets will fly from your hand to the spots where the base magnets are.
Another choice is to buy a steel grid table from one of the Chinese laser importers in the US-several around. Then use rare earth mags as needed but you will need wider and thicker magnets. You can also epoxy magnets in several locations in your alum grid but you are stuck with the setup pattern.
Best Regards,
George
Laserarts

[Joe Pelonio]

I keep around several old 1/4" Acrylic sheets that have had a lot of pieces cut out of them, so they are like a grid. Then I use either double sided (thin, not foam) tape to adhere the wood to it, or in extreme cases, drill a hole or two in the wood, in an area that will not be used, and wire it tight to the acrylic. This aso works on Rowmark when doing a lot of large text that makes it warp from the heat when engraving.

[Joe Hillmann]

I use a vacuum table and masking tape. The tape is only used to make a mostly air tight seal between the wood and the table. It works better than anything else I have tried. It doesn't get in the way like magnets can if you put them in the wrong spot. It keeps small pieces from being blown out of place. And when cutting large pieces it prevents the piece that was just cut from warping.

So far the only problem is noise. But there are several ways to solve that.

[Ben Halop]

Quick question. I have the 75 watt version of the Epilog Helix and I was under the impression that one side of the grid is aluminum and the other allows for magnets? I do show on Page 56 of the manual that magnets can be used to secure objects to the table. Epilog refers to the table as the task plate, and I have gone through the manual just now but have not found further documentation supporting my claim.

I do however have a magnet in my hand, and when this etching job completes I will pull the tray and test the bottom side. This upward facing side how I have it now is not magnetizable.

EDIT: Ok just testing my theory and yes one side of the task plate is magnetizable. :) I am unsure if you're 50 watt version is the same but I would think it would be. I think I'll start using magnets on my 1/8" plywood now cause I had the same issues and was just using wide painters tape. So ya, flip over your task plate and give it a try :)

[Michael Kowalczyk]

Not trying to plug us but that is the reason we offer both horizontal and vertical grain sheets. We use vertical grain for all our small projects like key chains, biz cards, jewelry, etc... I have converted our table to be a vacuum also but most of the time a vac is not needed on vertical.

[Joe Pelonio]

Quick question. I have the 75 watt version of the Epilog Helix and I was under the impression that one side of the grid is aluminum and the other allows for magnets? I do show on Page 56 of the manual that magnets can be used to secure objects to the table. Epilog refers to the table as the task plate, and I have gone through the manual just now but have not found further documentation supporting my claim.

I do however have a magnet in my hand, and when this etching job completes I will pull the tray and test the bottom side. This upward facing side how I have it now is not magnetizable.

EDIT: Ok just testing my theory and yes one side of the task plate is magnetizable. :) I am unsure if you're 50 watt version is the same but I would think it would be. I think I'll start using magnets on my 1/8" plywood now cause I had the same issues and was just using wide painters tape. So ya, flip over your task plate and give it a try :)
Doesn't the Helix have a built in vacuum table?

[Keith Outten]

This is how I keep material flat. My Corian vector table is flat so I can place tape around the perimeter of the material. As there are no X or Y fences so the tape can pull directly downward and keep the material flat to the table surface. Note the tabs on the tape so I can remove the tape quickly.

No vacuum or magnets required :)
.

[Scott Shepherd]

You guys are looking at this all wrong. You sent the warped jobs to your competitors :p

[Ben Halop]

Doesn't the Helix have a built in vacuum table?
Yes it does. I haven't had much need for it yet as my warped stock was easily held by some tape. If it weren't for having to switch up what size stock is in my machine every half hour on some days, I might utilize the vacuum table more. But for now it has just been faster to tape the couple pieces that need it every now and then rather than cover and uncover holes with the tape.

[Larry Robinson]

Here is my solution to warped wood hold down. Use up to 6 (3 each side) of these, but usually just one in each corner works well.

258264

[Anthony Welch]

I use the large clips on the perimeter and a couple of 3x12 ceramic tiles stacked on each other to hold down out of the way of the cutting area.258334

[brian fithian]

Try using Scuba Diving weights. The 1, 2 & 3 lb solid weights work very good and they fit under the rail on my epilog. They also sell weight bags that have lead balls the size of BB's in a mesh bag. They will lay flat enough as well to fit under the rail. You can buy these in weights from 1lb to 5lb each. This method works great for me with wood that has the worst of bows in it. Had to go by extra weights...Last dive trip I was missing half of mine when we got on the dive boat. They now belong to my shop

[Bill Cunningham]

I have a few 2& 3lb lead weights as well, I also have some 1.5 x .5 x 18" & 12" steel bars. The bars can be placed where the engraving ain't and their heavy enough to hold most 1/8" flat to the grid.

[Bryce Mccloud]

So are most of these solutions for engraving warped wood?I ask because I'm encountering the same problems with warpage but I need to cut all the way through my 1/8 birch and I assumed my solid job plate was for engraving only.We finally made a pin plate like jig with fingers around te edges but that has brought its own set of challenges!

[Larry Allred]

Long time since I posted the question. Thanks for the advice and great ideas. Bryce, you probably figured it out by now... the solid plate IS for engraving. Gotta have a grid for cutting. Thanks again! Larry

[Bill Cunningham]

So are most of these solutions for engraving warped wood?I ask because I'm encountering the same problems with warpage but I need to cut all the way through my 1/8 birch and I assumed my solid job plate was for engraving only.We finally made a pin plate like jig with fingers around te edges but that has brought its own set of challenges!

if you go to a sheet metal shop, or someone that does heating and ventilation you can probably buy some aluminum grid.. This is the same .5x.5 grid that home depot stocks in plastic, but this stuff is aluminum and works great.. Or maybe that's grate :p

[Doug Griffith]

Here's something I do every now and then.

Blind rivets pressed into the honeycomb table. 1/4" rivets fit in my table with just a small amount of tension. Enough to hold material down but loose enough that I can still pull out from the top with my fingernails. I probably wouldn't do it too often as I'm sure this method puts some strain on the table. My table is well worked so I don't really care at this point. It's all about getting the job done.

http://www.sawmillcreek.org/attachment.php?attachmentid=252351&d=1359059217&thumb=1 (http://www.sawmillcreek.org/attachment.php?attachmentid=252351&d=1359059217)http://www.sawmillcreek.org/attachment.php?attachmentid=252352&d=1359059240&thumb=1 (http://www.sawmillcreek.org/attachment.php?attachmentid=252352&d=1359059240)

McMaster Carr #97387A347 (http://www.mcmaster.com/#97387A347)

http://www.mcmaster.com/#standard-rivets/=l6fjq2

(pulled from an earlier post of mine)