plastic name tag bows...

[Linda Kroeker]

Is there some way to stop the bowing of name tags...I know they are bowing
because of me taking so much of the top blue color off. I tried taping and covering the holes on the table to help keep it flat...doesn't work.
I even left about 3/8" margin on each side of the tag while it was lasering.

[Doug Griffith]

Haven't done it but you may be able to anneal the plastic afterwards by heating in an oven and letting cool slowly. temperature and timing are key.

[Frank Corker]

The only reason for that type of bowing is that your power is too high. Try reducing the power and keeping the speed up. The frequency is probably at 5000, experiment at 1000 2000 3000 4000 you will probably find an ideal which will stop that from occuring.

[Mike Null]

Heating and holding it flat under a piece of scrap metal will probably work. Or heat it and jsut bend it back to shape by hand. If you don't have a heat press try buying a heat gun at harbor Freight. They're usually about $10.

Nice job of engraving.

[Rodne Gold]

Your problem is that you are engraving away a huge amount of material up at the bottom to leave the blue standing out and are putting incredible amounts of heat into it , worse still , its not the full namebadge but only a portion of it, this is almost certain to make the badge warp.
Consider changing the design to white surface blue engraving material at the bottom and the converse up top , glue the 1/2 badge blue portion on the top of the white/blue engraved with name full sized badge. Will make it look 3d and make it uber rigid.
If you persist in doing it the way you are , I dont see a solution.

[Scott Shepherd]

I would think that would be a good dye sub application with that much area of contrasting colors. Maybe a dye sub person can comment.

[Mike Null]

Steve

When I first looked at it I thought it was CLT. Clt on laminated will warp slightly but it's very easy to straighten as it cools.

You could also do this nicely with dye sub.

[Dan Hintz]

its not the full namebadge but only a portion of it, this is almost certain to make the badge warp.

If the badge was warping top to bottom, I'd agree, but the warp is from side to side.



Linda,

How many badges are you cutting at once? If you're not already doing so, you may reduce the heat into the substrate by doing as many across as possible, which leaves the laser on a single tag for a reduced period of time (though if you're going really slow over each tag, this will be meaningless). If you're using a vacuum table, leave it on the table longer if the tags are still warm... letting them cool while still pulled flat would accomplish the same thing as reheating them. On the same token, consider reheating the tags with a heat gun before removing them from the laser/vacuum table.

[Doug Griffith]

What you're doing is introducing shrinkage to the top side of the tag. Dan's method of doing as many across as possible may help. If you reheat with a heat gun, apply the heat to the back to help balance out the shrinkage.

[Linda Kroeker]

The plastic is reg. 1/16" blue/white core...I sheared them not laser cut.
I used 300dpi and also tried 600dpi...no difference and 100s 40-50p...The customer was very happy with them, which is what matters...just thought
there might be some way around this issue.
Thank you all for your advice...I love this site! Most of what I have learned
in my short time of lasering is all thanks to the creekers!

[Mike Null]

I thought you cut them with a shear. did you engrave them before you cut them or after.

If you cut them first then I suggest you engrave first and score a line for cutting with the shear. I cut with the laser and don't usually encounter as much bowing as you're getting.

[Linda Kroeker]

Mike,

I lasered them all then sheared them. I will try your heating method.
I know it's because I lasered so much off the top. If I try a lower power than I have to run them twice.
This is not usually a problem since I don't do 2 tone tags too often.

Thanks for your help.

Linda

[AL Ursich]

Would be a nice project for Sublimation too.... And that is what I thought it was too at first... I have that problem some times with FRP Sublimated tags but since I go from press to between 2 Glass Cutting Boards with weights I have not had a problem.

I would get some glass and heat them with anything from a hair dryer to a heat press them between glass with weights.

Great Tips Frank.... Thanks,

AL

[Bill Cunningham]

If there is a slight warp in the badge, simply gluing a 1.5" plastic backed pin to the back will flatten it out. The pin backing is flat, and a lot less flexible than the badge.. Sort of like a splint.. If your doing a bunch, doing them all at once, then cutting them out with the laser is a lot faster, and does put less stress on the badge..