Tape covering of material to be cut/engraved

qa

#1

This hasn’t been a topic of discussion for a bit, but a question that now pops to mind that I hadn’t seen addressed specifically (emphasis on me not having seen it).

Is the transfer tape/sheeting on materials to be cut/engraved “SOLELY” to minimize burning of the material surfaces or is it required to obtain optimal optical reading by the cameras (as in you can engrave/cut without tape on the material, but the precision may not be as good as it could be)?


#2

That was discussed here.

http://community.glowforge.com/t/will-glowforge-sell-or-recommend-a-premask-material/947


#3

@karaelena yes, that link has all the info you should need.

To sum up your question. For wood and such its not NEEDED but helps with burn marks (focus will be fine) however, anything transparent will probably need it to focus. Here is where you can buy it.


#4

Thanks for the links, but I do not see that that post addresses my question.

My question is not about “how” to use masking material or which type/technique for using pre-mask tape is best, my question is about pre-masking material usage and how it relates to optimal optical reading by the cameras (if at all). Is pre-masking required for optimal results locating material, optimal depth or curvature determination of material, etc?

Thanks in advance.


#5

Generally with pre Glowforge lasers…you either manually measure the focal length with a tool or input the thickness of the material and the laser adjusts. I guess with the Glowforges ability to optically measure the distance from the material, then I can see where tape over clear stock or mirror is essential so the camera has something to focus on.
I use tape for acrylic, sign plastics and some wood to protect from burn marks and smoke. I also use the tape for masking if I want to cut out a shape, remove the tape only on the shape and paint like here


#6

No more exacto knife!
Cutting a mask is about to get simple.

Nice fix for a universal problem. I notice “clean” just after I dump a handful of dinner’s silverware into the basket of clean… wow, those glasses look shiny.
Oh well, can’t be too clean - run it again.


#7

wow, that is expensive tape! My transfer tape is nearly half that price (transferRite from signwarehouse)


#8

Oh wow!!! Thats soooo much cheaper!!! TransferRite is laser safe?


#9

Somewhere I thought there was a comment in a topic about using the masking to cover a clear material so that the camera could register its height properly. Can’t find it anywhere. So @jdodds, I understand your question as it relates to the Glowforge. I’ll keep looking.


#10

Unless the tape has a pattern printed on it, I would think it would be difficult to use it as a focus target.


#11

I believe TransferRite is laser-safe, at least the 582U and the 592U (medium- and high- tac)
It is made by American Biltrite Inc., who call it a “protective paper laser masking” and are one of the only tape manufacturers that I have seen who have an MSDS available.

American Biltrite_6000_series _ULTRA[2015-11-01].pdf (154.4 KB)


#12

Fantastic!! Thank you! You just saved me some $$!


#13

I can’t find it either. I doubt they used a pre-mask to etch the back of the ipad, but that surface probably has a lot of the same characteristics as pre-mask tape from an optical sensing perspective. The camera on the Glowforge would have to be dynamically sense for the surface height for correct distance over the entirety of the curved edge surface. Wood on the other hand probably doesn’t have the same light reflective characteristics as pre-mask tape and forbon, definitely not.


#14

USCutter has paper transfer tape in rolls of various sizes too… also much cheaper than Laserbits.

I don’t know for sure if any of the sign industry tapes are laser safe, but I suspect that any paper-based tape is probably OK.

If you look in the specifications tab at US Cutter you can see the adhesive type, at least on some products. For example, this one specifies latex adhesive. Paper plus latex seems like it ought to be laser-safe.

http://www.uscutter.com/Main-Tape-GXP750-PerfecTear-Plus-Medium-Tack-Transfer-Tape


#15

Ahhhhh. . . . . Run, there’s been a hijacking! ! ! :spy:


#16

One of the hijackers here… sorry for the delay… we will try and get you to your original intended destination.

Aside from the glowforge official materials (which of course have the material id codes on the masking) I would imagine that anything opaque and matte would read similar to masked material. Translucent and or reflective materials could potentially cause more of an issue for the optics.

I would hope that between the two cameras, the ramp-able interior lighting, and some trick computer-vision, that focus-precision will not be affected one way or the other by masking.

Maybe someone at the GF office can give a simple answer:
@aeva or @madebynick, can the glowforge “see” a piece of clear acrylic with no masking on it?


#17

Maybe I shouldn’t assume but I thought blue painters tape or regular masking tape would work fine


#18

It probably will, but it is probably going to be more expensive than large rolls of material made for this purpose.


#19

Let’s take it a step further: can the cameras judge distance on masking with no features, i.e., solid color?


#21

I just hope that manual focus will be an option. (I searched the forum a little, but I didn’t come across a definitive answer.)

I’m assuming most of the material I cut will be flat, so I hope I can just set up the machine to make the cut at a static focal distance so it doesn’t automatically “fix” the focal distance “for” me.