Hi.
It will.
And You can also laser through glass with visible wavelength laser, another way to ensure flatness with cloth and paper products, and to reduce the amount of oxygen (=cleaner cut) in the process.
Basically, if You can clearly see through a material, a visible wavelength laser will pass through pretty much unobstructed.
Pretty much, because inpurities and additives -as well as any coatings- in the glass will absorb a few percent of the energy.
When lasering through glass, a few percent of the energy will also be lost because of the different densities and optical properties of air and glass, but those losses can usually be fully compensated with either reducing the speed and/or increasing the power a few percent.
Yes, the “pins” should have a soft surface though, glass does not like stress-points.
If You have the glass high enough, You can use magnets with the glass as well.
The underside magnets should be rubber coated and not to be slammed onto the glass with the top magnet for obvious reasons
.
True, handling (large) sheets of glass gets difficult and dangerous really fast.
Especially under the fabric to be cut, it won’t make any difference whether there’s one or several sheets of glass.
And probably not much if lasering through the glass either.
These:
https://www.wpg.com/catalog/hand-held-vacuum-cups
are Your best friends when handling any flat glass products by hand.
Those plunger style suction cups may seem rather expensive regardless of the brand, but the cheap cam operated hardware store varities will fail sooner or later.
Been there, never again.

Like @ednisley there said, that’s pretty much bollocks.
“Alternate fact” is somewhat accurate statement, because there’s actually a hint of thruth behind that claim.
Because the average focus spot size of a budget 5W diode laser is generally much smaller than the focus spot of a CO2 laser for multitude of reasons, the energy density may well be equal.
Or even signifcantly more if the spot size of the diode is exeptionally small, and the spot size of the CO2 laser is large.
But:
Means that comparing those two different types of lasers by just one variable is utterly fruitless.
I have very little experience in cutting fabrics (just a few tests), but if I were You, I’d probably test (or coax someone else to test
) the power requirements and the expected cutting speed with a 600x600 bed diode laser first, before purchasing the head.
If I had to make a semi-educated guess, I’d say that while the 5W diode is ok for marking fabric, cutting fabric with any reasonable speed will require 20W or so diode.
The spot size will increase with every additional 5W, but since kerf plays an insignificant role when cutting fabrics, that shouldn’t pose a problem.
Regards,
Sam
