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Discussion Starter · #1 · (Edited)
SWMBO has lots of friends with dogs. Several dozen in fact. this year she saw a paw shaped, personalized, laser cut, wooden ornament that she wished she could give something like that.
Well, being the magician that I am, and SWMBO's wish being my command, the next thing you know my new Atomstack M50 is punching them out like Christmas cookies.
I started with a couple of 2' lengths of scrap #2 common 2x4's I had in the bin. Slicing them into 3/16" slabs only took one cut from each edge. Quickly, I had a stack of fairly clean white pine blanks 3/16" x 3-1/2" x ~24".
The various elements of the paw, snowflakes, and stars, plus the year text, were combined in paint.net to form a 3" x 3" template at 300 dpi that the laser wants. Because of grain direction on the hanger, it was determined to rotate the images 90° for strength.
The main pad of the paw had the pets name added. Due to the wide variety of names, many different fonts were used, based on what fit best for each name. A tie bar line was drawn at the bottom of the letters so that the lettering wouldn't fall apart.
Dishware Cuisine Embellishment Pattern Wood

Slow cutting burns and chars and even bursts into flames. Faster speeds cut shallower without as much scorch. Multiple passes are needed and the hardened outer faces needed extra passes to cut cleanly. My system has a 5w laser that I run at 80%. I bought the "better" focused beam module. At 600 mm/minute it averaged 12 to 18, about two minute, passes. I supported the far ends of the board so the pieces would fall thru as cutting was completing.
Wood Gas Wood stain Machine Hardwood

The pine, overall, cut well and evenly. I avoided knots (mostly) as they don't cut worth a damn. I also hit a sap pocket that flamed off and bodged up a small area on one.
After lasing with GRBL software, many pieces fell free on their own. But about half the cutouts needed a little wiggle to get loose as the pattern cut was intricate and the kerf narrow. Some pieces would have more or fewer fibers uncut, even though the piece as a whole had fallen thru, rendering further passes impossible. These pieces usually just took a little coaxing from a jewelers screwdriver, or at most an Xacto knife to get loose. Out of a run of almost 50, I think I had to remake three. So about a 6% reject rate.
Once the swarf was all removed, the pieces were sprayed front and back with iridescent spray glitter sealer and allowed to dry completely. A loop of festive 1/4" ribbon was added as a hanger to complete the ornament.
The completed pieces look like a tray of Christmas sugar cookies.
The advert she'd seen originally was pricing these out at $10 each + s&h. Given the number we made at $10 a pop, this $300 machine paid for itself on this one job alone. (I know its play money, since I'm charging myself, but it's fun to pretend!) Took a couple of days of sitting in front of the computer surfing while they cut, and a minute or two every 1/2 hour or so, to set up for the next unit. The one thing is, when lasering, the machine CANNOT be left unattended for any length of time. I work with several fans running and a fire extinguisher handy. Also, WEAR YOUR LASER SAFETY GOGGLES. Remember: Do NOT look into beam with remaining eye.
 

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Cool Idea, but I'd imagine the job would be easier if you knew all the pet names first :D

I'm still tweaking the settings on my laser but I have cut some 1/4" hardwood just to see how much time/energy it requires. I have found adding the tabs to keep parts attached during through cuts really depends on how easily the wood burns. Sometimes the tabs just get burnt away and, well, are useless.

Are you using any air surrounding the beam? Curious if it tends to turn smoldering into flames when used on softwoords.
 

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Discussion Starter · #3 ·
Cool Idea, but I'd imagine the job would be easier if you knew all the pet names first :D

I'm still tweaking the settings on my laser but I have cut some 1/4" hardwood just to see how much time/energy it requires. I have found adding the tabs to keep parts attached during through cuts really depends on how easily the wood burns. Sometimes the tabs just get burnt away and, well, are useless.

Are you using any air surrounding the beam? Curious if it tends to turn smoldering into flames when used on softwoords.
Go to 3/16 material instead of 1/4". That last 1/16" is hard to cut. 1/8" is even better.
The laser head has forced air cooling and a nozzle around the beam so it's blowing smoke out from the beam.
Total laser fluence is what cuts. Two passes at, say 600mm/min, will cut as deeply as one pass at 300mm/min, the net fluence is the same. Flames come from heating (not cutting). If the beam is emitting bright white light at the material, it's no longer cutting. Instead, it is reheating the carbon left from previous passes to white heat, and not doing any additional cutting.
 

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Go to 3/16 material instead of 1/4". That last 1/16" is hard to cut. 1/8" is even better.
The laser head has forced air cooling and a nozzle around the beam so it's blowing smoke out from the beam.
Total laser fluence is what cuts. Two passes at, say 600mm/min, will cut as deeply as one pass at 300mm/min, the net fluence is the same. Flames come from heating (not cutting). If the beam is emitting bright white light at the material, it's no longer cutting. Instead, it is reheating the carbon left from previous passes to white heat, and not doing any additional cutting.

The total cut depth isn't really a problem as I can blast through with just power and slow speed, but totally agree with more passes and faster movement to get a cleaner and smoother cut edge. If I do more of these type cuts I'm thinking about trying a focused air jet that will follow the beam to help clear out leftover carbon.
It certainly is a balance act to get the best cut and that setting changes depending on the wood type and even the conditions in the shop on that day.
 

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Discussion Starter · #5 ·
The total cut depth isn't really a problem as I can blast through with just power and slow speed, but totally agree with more passes and faster movement to get a cleaner and smoother cut edge. If I do more of these type cuts I'm thinking about trying a focused air jet that will follow the beam to help clear out leftover carbon.
It certainly is a balance act to get the best cut and that setting changes depending on the wood type and even the conditions in the shop on that day.
Don't use so much air to cause the target to shift during the runs.
 

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nice work! i cut a lot of dog ornaments on a scollsaw out of 1/8" bb ply. wondering if that might be easier to cut on a laser tan pine? i think the ply would be more durable,too. ive dropped a few of them cut out of bb without harm. seems pine might break into who knows how many pieces.
 

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Discussion Starter · #7 ·
Actually 1/8" bb ply doesn't cut worth a damn! (at least on my 5W rig, YMMV) I think "engineered materials" may have fire retardants built in. The various materials in the plys cut badly. The 3/16" pine cuts much easier and cleaner. Given the size and weight they're plenty strong for the intended app. The grain was oriented the tall way for strength. Since the cuts don't align on the grain, it's stronger than it looks, but yes, you can snap one with your fingers. But it's a lot tougher than a glass ornament.
 
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