ColorCore, etching vs engraving

[David Ford]

I am considering making a sign using black on white King ColorCore material and have a few questions for Creeker's experienced with this product.

For some backstory, I recently made a sign using a 4'x8' sheet of clear cabinet-grade birch plywood, 5 coats of weather proofing applied before lasering then 3 coats of automotive clearcoat (a body shop sprayed it) over the lasered text. The text has faded to the point of being illegible within a month hence my search for a replacement material.

After looking at the King Plastics website the product I am considering is the 1/4" thickness with a 0.025" cap (10% of nominal thickness).
http://www.kingplastic.com/Products/Colorcore.aspx

My questions:

a/ Would this be your first choice of material for this application?

b/ I have a 25w Camtech L20 (tests at 33w). Will I be able to achieve a good clear result on ColorCore with this machine? My supplier would have to order this in so a small test sample from stock in advance isn't available.

c/ Is ColorCore truly long-lasting in respect to UV damage in a high-UV exposure situation? My sign will be facing SW with daytime temps ~90F under cloudless skies. My concerns are fade/yellowing, delamination, and warping.

d/ I am assuming I should mount the ColorCore sheet onto a base of 1/2" plywood then frame it (dadoed 2"x4" frame) for structural integrity. If so, should I use an adhesive or not? Black panhead screws through the non-etched portions?

Thanks in advance for any input, hopefully I get to the point of being useful enough to chime in with an answer or two someday.

Cheers,
Dave

[Larry Bratton]

Are you sure you can laser this stuff? A .025 cap is thick considering that typical Rowmark laserables are like .003. I have tried lasering thicker caps with 40-45 watts and it's tough to get through.(for example Rowmark Granites at .038, its even tough with a rotary) Your at 33w. What does the manufacturer say?

[Mark Giese]

I can't speak to lasering colorcore, but have cnc'd a bit of it. First, supply on it is an issue, you may not be able to get color choices immediately, when i spoke with my supplier on Monday very little was readily available from King. Order time 8-10 weeks, and king is just across the state. The economy has hit that product line hard, same goes for compression polymers version of it. Tough to find color choices. And desired thickness and color... play the lotto if they say yes we have it.

It is essentially a polyethylene product. I have not found an adhesive that is permanent. Some will hold a week, some two, if you get really lucky maybe three... It must be held with mechanical fasteners, ie screws. if you are going to fasten it to another substrate. or it's self for that matter.

It has a pretty low distortion point, and though i have NO experience cutting it with a laser, the first thing that comes to mind is the youtube video of lasering sticks of butter.

I have a very small piece (to small to be usable in any meaningful way) of leftover .25" Black White Black, i would be happy to send it to you if you think you want to try it. If you want any other info feel free to email me.

-Mark

[Larry Bratton]

David:
CNC would definitely be the way to go with that product. A probable good way to bond this to another substrate would be 3M VHB tape. I would have my doubts though about the durability for the long term. The lead time would be a killer for me.

I make 4x8 signs for outdoor use from Celtec PVC and bond laser cut acrylic letters to it. Great stuff. I paint it with Sherwin Williams Super Paint (plastic formula) It's readily available and doesn't cost an arm and leg.

[David Ford]

Based on the experience/advice you guys offer ColorCore seems like the wrong material for lasering. Thanks for saving me a pile of frustration and money. As to availability, my local supplier can get it (4'x8'x1/2" B/W/B) from his supplier in Vancouver BC on a next day ship basis. Or so he said.

Any thoughts on Alumacorr?

[Larry Bratton]

Aluma-corr is a good sign material for certain applications. I do not think of any laser operations that can be done on it. It is aluminum sheets over a core of corrugated polypropylene. It's great for use with vinyl lettering. You could mount acrylic laser cut letters to it or maybe something like Rowmark Laserlights etc. Be fine for outside.

[David Ford]

Aluma-corr is a good sign material for certain applications. I do not think of any laser operations that can be done on it. It is aluminum sheets over a core of corrugated polypropylene. It's great for use with vinyl lettering. You could mount acrylic laser cut letters to it or maybe something like Rowmark Laserlights etc. Be fine for outside.

My mistake then, I thought the sheets were anodized aluminum over corrugated polypro, the ano-alum being laserable to reveal the bare aluminum.

[Larry Bratton]

My mistake then, I thought the sheets were anodized aluminum over corrugated polypro, the ano-alum being laserable to reveal the bare aluminum.
It's painted aluminum.

[David Ford]

It's painted aluminum.

Ahhh, that explains the relatively low price of it.

[Larry Bratton]

It's really light too, I think a sheet weighs about 30 pounds or so. I don't know of a supplier that sells engraving plastic in 4x8 sheets.
I make a good many signs on PVC sheet as a back (Celtec) with laser cut acrylic letters glued on with acrylic cement.