Laser basket weave from veneer #1: Intro Blabbering

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This is part 1 in a 3 part series: Laser basket weave from veneer



I did this pattern before as one of my first stabs at cutting veneer with my laser. This time I was going to better document the process and instead of an experiment, I actually had a plan! (sort of).

I've always liked this pattern, From a technical perspective, best thing is all cuts are straight and square. Worst thing is all cuts must be straight and square 🤔

A little off on either, and gaps will form and propagate throughout the design.
Before I tried laser cutting, I'd use a cheap veneer saw and Exacto knife for straight and clean edges. I did ok, but the knife tends to follow the grain and my saw sucked. Plenty of age old techniques and skill required for even this simple-seeming task, something that people like Paul {shipwright) have long ago mastered but not me.

In comes the laser. Burn the buggers out!
Where a good knife will leave a clean edge and with a slight taper, a perfect gap-free fit, the laser will leave a gap due to the beam kerf and a charred edge.
Several things can be done to minimize those "features"

The Laser

I have a 10 Watt optical power diode laser (my first). Typical hobby grade unit. To use one, good software that goes far beyond anything delivered with the device is required. At this time, LightBurn is at the top of the heap. Really lets you get the most out of the tool for a cheap price.

My setup is a swing down table in my spray booth. Ventilation and compressed air are already there so a perfect place to work.


This is the Ortur Laser Master 3 (LM3), a typical gantry style with a 400mm x 400mm workspace.
One can go nuts with setup. Since I also use this space for finishing, the table gets folded down and the laser set aside. I placed 3/8" steel pins to replace the feet in the corners of the frame. Matching holes in the table top allow it to be securely located in the exact same location when setting up. A backer (spoil) board from a scrap section of Hardie siding (cement based) keeps the laser beam from cutting a hole back to China in the table top. I burned a layout grid on it's top so I know where to place things to cut/etch, even if it's been months between uses. You can see the wood blocks used to align this spoil board to the table.
On top of that, to hold the stuff being cut I use a piece of fluted glass I had. The peaks hold the veneer while the flutes let the smoke escape from below.

There are lots of other ways to get a working setup, this is what I had handy.

Air Assist

The laser head has internal fans to keep it cool, but when lasing most materials soot and smoke will be created. There also is an advantage to blowing air into the cut to clear away burned crud.

Most of the lasers will route this airflow through a "funnel" that also surrounds the laser lens, this airflow will help keep the smoke and soot off of the lens. If anything builds up on the lens, the beam will begin cutting your lens and quickly trash it.

Not much air is needed, even a good aquarium pump will do. I found a cheap airflow regulator so I can record exactly what I use for each material. The key is airflow, not air pressure since if you change a hose the pressure will also change, but if you just keep the airflow constant, you'll get the same results at the laser.


Mounted in an old cigar box with a slip in lid that makes for easy removal if I need to. Measurement is in Liters/minute (Litres/minute for y'all across the ponds 😬)

Anyhoo, onto the project in part 2


26 Comments

Must...not...follow...this...thread.  (Already too many toys in my shop).  

--Nathan, TX. Hire the lazy man. He may not do as much work but that's because he will find a better way.

i wanna follow since i already have a small cheap laser for burning logos, not cutting.  but i dont wanna go own splints rabbit hole either !

working with my hands is a joy,it gives me a sense of fulfillment,somthing so many seek and so few find.-SAM MALOOF.

Will follow.    Thanks.

Ron

Tis a rabbit hole, just like any other tool 🤠
Yes. Yes. Excellent. More! More! Muwhaaa!!

Ryan/// ~sigh~ I blew up another bowl. Moke told me "I made the inside bigger than the outside".

Great intro into the labyrinth of laser cutting Splinter.

Gotta admit I immediately thought laser engraved as opposed to the heroic cutting of veneers... though engraving could leave little stock "under" the engraving.

I've never tried cutting veneer per se on the laser as I was always intimidated on the air blowing small pieces away.


just my 2 bobs worth...

I've always laminated veneers onto 3mm (or dressed down further) MDF

and have some meat bacon rasher (size) to cut through.

When I cut inlays, I cut upside down on the assumption that the kerf is a fraction wider at the top and  narrower at the bottom where the laser strength is diminished.
During assembly the minor bevels will assist in jamming the pieces together.
This is probably irrelevant in your scenario, however, it is a method that has worked for me.

If your first cut is too short... Take the second cut from the longer end... LBD

Yeah, I'm still itching to "defocus" my laser to see if I can get a similar taper on edges.

Your idea of cutting after laminating is ideal with your mega watt device, if I tried that things probably would catch on fire after 10 passes.
I'm only talking 2mm... ok, 3mm once laminated.

BTW, to all laser owners... if you are concerned about fire, ditch your powder extinguishers and go for CO2.  Powder will do more damage to the laser that he fire.

If your first cut is too short... Take the second cut from the longer end... LBD

Perhaps a fire blanket would be even better?  Also no residue to cleanup.  I have read that CO2 is not great on flammable solids?  I have no idea if the blankets really work but the ads on Instagram sure look promising?  

--Nathan, TX. Hire the lazy man. He may not do as much work but that's because he will find a better way.

Blankets work by smothering. Which can work fine, as long as there isn’t a ton of trapped air. So, probably not great for a laser in an enclosure. And any tight weave wool blanket will work, but the ones they sell are usually a fire resistive synthetic. 

CO2 has a smothering effect as well, as it displaces air but is somewhat short lived. It also removes heat which attempts to brings the temp below ignition temp which will also stop the fire. The nice part about CO2 is that you can direct it right where it’s needed, but it does mean you’ve got to be a little more up close and personal (as opposed to dealing a blanket over something and moving away). There’s no clean up at all, but if a large amount is used in a confined space it could be an issue for someone trying to breathe. 

‘Regular’ extinguishers, sometimes called Dry Chemical extinguishers, are mostly Bicarbonate powder based, with some other stuff. The powder is super fine and spreads very easily. It kinda covers/sticks/melts to burning items and smothers them. They leave a LOT of residue and are a pain to clean up, but they work well and are cheap. 

There are about a dozen more types, but that’s enough for lasers!

There. Now you know more than what you ever wanted to about fire extinguishers…

Ryan/// ~sigh~ I blew up another bowl. Moke told me "I made the inside bigger than the outside".

Random thought...I wonder what affect using a bottle of CO2 for the air assist would have on the cut?  If there is no oxygen available, will it still cut?  Might that reduce surface or edge charring?  🤔

--Nathan, TX. Hire the lazy man. He may not do as much work but that's because he will find a better way.

Interesting 🤔

Seems like it shouldn't affect the cut since it is the heat that does the work.

As to fire extinguishers, I have a couple of halon units pulled from aircraft. I wonder what residual effect they might have on electronics?
I think that Halon is another gas which typically used with electronics or other places where water or other residues might damage them.  Data centers typically use  or at least used to use Halon for fire suppression.  

--Nathan, TX. Hire the lazy man. He may not do as much work but that's because he will find a better way.

Halon was a great gas. It’s heavy and works to displace oxygen without leaving residue. Perfect for electronics and the like. The downside is that it’s very destructive to the ozone layer. That’s why it went away. It’s not actually really harmful to humans, other than it can suffocate you by displacing O2. 

Ryan/// ~sigh~ I blew up another bowl. Moke told me "I made the inside bigger than the outside".

When I was working, the major electrical vaults and control rooms were protected by Halon. 
We have several large computer "machine rooms" that were equipped with Halon. They had to switch over to something else for a newer room, but were allowed to keep the current system and a large stash of refill Halon for the old system.

My concern is that out room with the halon has all sorts of stuff that shuts down (ventilation) and drop down door covers before the discharge. Me thinks it wants to take over the atmosphere in the room and if my laser has it's ventilation running, the halon may just get sucked out and just piss of AlGore.
Yeah, smothering gasses (that’s what they’re called) don’t work well if they’re stirred up. They want to dump and stay in a thick, constant layer. Vent stops and seals would be very common for a halon system in that type of environment. 

Ryan/// ~sigh~ I blew up another bowl. Moke told me "I made the inside bigger than the outside".

Hey guys, we're talking about a smoking laser flare up and not bushfires.

I was advised against my on hand powder job sitting next to my laser and recommended a CO2 by my laser service guy.  Just passing on... "horse/water/drink" thingy.

If your first cut is too short... Take the second cut from the longer end... LBD

You wanna really freak yourself out, walk into a room after an SF6 (surfer hexaflupride) release. It’s another, less commonly used, smothering gas. Usually around really high voltage stuff. When I was a young fireman, we went on an alarm call in a manufacturing clean space. We met with staff who said they thought it was a misfire of the system because their instruments didn’t show any issues. They left out the SF6 detail so we just thought it was maybe a Halon system, at least I did. We walked in and looked around. Didn’t really see anything. My Captain called out to me from across the room and it sounded like his voice was about 6 octaves lower. I answer him back and sounded the same! We both freaked the hell out and ran out of the room trying to put our breathing apparatus on as we were running. The staff outside met us laughing. ‘Never been around Sulfer Hex before, huh??’ Scared the bejeejus out of me!! 

Think of it as the exact opposite of helium. Goes away just as fast!

Ryan/// ~sigh~ I blew up another bowl. Moke told me "I made the inside bigger than the outside".