Getting great results out of a laser cutter takes some effort to make sure all the settings are just right.But even then, if the air between the material and the laser source is filled with smoke and debris, it can interfere with the laser beam and affect the results.The solution is to add air assist that continuously cleans the area.
Earlier this year, I bought an Ortur laser engraver/cutter and have been improving it to increase inventory capacity.Last month I talked about placing a plate under the machine to allow the laser to move up and down easily.But I still don’t have air assistance.Since then, I’ve found a nice way to add it that works with many laser cutter setups.
I didn’t design any of these modifications, but I did change them to suit my specific situation.You can find my very simple modifications to other designs on Thingiverse.You’ll also find links to original designs, and you’ll need them for extra parts and instructions.It’s great to be able to work from talented people and draw on each other’s ideas.
At the end of the previous post, I had installed an air assist system but cut the air hoses because I never took the time to boil some water to bend the air hoses.However, it did allow me to move the laser head up and down easily, which was very useful.
This isn’t the first air-assist design I’ve tried.If you look at Thingiverse, there are a lot of different opinions.Some have 3D printing nozzles with air needles or 3D printer nozzles.Some just direct fan air over the part.
I found something inappropriate or not very effective.Others would interfere with the X stop or interfere with the Z movement of the laser, which admittedly wouldn’t be a problem on a stock machine.One of the designs had a custom top plate for the laser with a little hose guide on it and even though I didn’t keep that air assist item I didn’t remove the custom top plate and it turned out to be lucky as you’ll see .
I’ve been very interested in installing air assist since I saw [DIY3DTech's] video on how to improve the cut.I even bought a small air pump for this purpose before the laser arrived, but for lack of a good way to direct the air, it was mostly idle and unused.
In the end, I found [DIY3DTech's] designs to be very quick and easy to print.The bracket surrounds the laser head and mounts a small tube holder.You can adjust the angle and the 3D printer nozzle is wedged into the end of the tube.It’s a simple design but very adjustable.
Of course, there is a small problem.If your laser head doesn’t move, the stand is fine.However, if you can slide the laser up and down, the bracket needs to clear the large acorn nut that holds the laser to the X bracket.
At first, I tried putting some washers to move the laser body away from the housing, but that didn’t seem like a good idea – I was worried that if there were too many washers, it might not be stable and I’d have to fish to add some longer bolts.Instead, I did some surgery on the bracket and cut the offending part so it was shaped like a U with about 3cm on each side.Of course, this removes the set screw, making it less grippy.However, a small double-sided tape will hold it well.You can also use some hot glue.
A nylon bolt (probably shorter) holds the black hose module to the white bracket.It also pinches the tube, so don’t screw it all the way down or you’ll pinch the airflow.A nylon nut locks it in place.Getting the nozzle into the tube is a challenge.You could heat the hose a little, but I didn’t.I just stretched the tube in both directions with needle nose pliers and screwed the nozzle into the widened tube.I didn’t seal it, but a dollop of hot glue or silicone might be a good idea.
The only other part of the air assist isn’t strictly necessary.I had a top plate from another air assist attempt that was still mounted on the laser and it had a small feed tube for the air hose which worked well with this design so I kept it.It keeps the hoses neatly lined up and you can also bundle the hoses with other wires if you want to keep the hoses from wiggling around.
Does it work?It does!Cutting thin plywood now only takes a few passes and seems to allow for a cleaner cut.The attached picture shows a small test piece on 2mm plywood.The contour was perfectly cut with 2 passes of the laser, and – looking at it up close – it seems like I could even lower the engraving power.Without zooming in, though, it looks pretty good.
By the way, these cuts were made using what Ortur calls a 15 W laser and using a standard lens.But keep in mind that the 15W figure is the input power.Actual output power may only be north of 4W.
What is another side effect of the air blowing from the right?You can see that all the smoke is now hanging on the left side of the machine.
Speaking of smoke, you do need ventilation, which is one thing I haven’t done yet.I’m still trying to figure out what exactly I’m trying to do.A vented hood or enclosure with an exhaust might seem ideal, but it’s a pain to set up.Right now, I have an open window with a double window fan that blows out.
Wood doesn’t smell too bad, but leather does.I also understand that some glues in plywood and some tanning chemicals in leather can create really nasty fumes, so that’s a downside of these machines.If you think printing ABS smells bad, you’re not going to be very fond of an open frame laser cutter.
For now, though, I’m pretty happy with the results this average machine can deliver.If you really need a laser cutter for commercial use, you’ll probably look elsewhere.However, if you want to spend a fair 3D printer cost and add a lot of functionality to your workshop, you’re probably going to do worse than one of these cheap engravers.
You won’t like the price, but George from Endurance Lasers has a 10w+ model that he verified with a power meter
As I’ve looked around, single diode lasers don’t seem to make any sense for high sustained output.It seems that carbon dioxide is still the only reasonable option for power output, and also works at better wavelengths for most of these tasks.
Higher and you’ll have to combine/align the beams, which may not be worth the trouble.Power blues are fun because they’re cheap and easy to make.
With the right amount of air and lots of time, I can barely burn through 4mm plywood with a “7 W” laser (2.5 W actually), but it’s dark, slow, and unpleasant.It will also fail if the inner layer has a knot or something.
If I was serious about laser cutting, I’d get K40 CO2.However, for tagging and just having fun, Bruce is cheap and low-commitment.
A solution that looks like a (highly priced) good one is to install a fiber laser on the 3D printer body.That might cut metal.
I’ve been curious about these guys: https://www.banggood.com/NEJE-40W-Laser-Module-11Pcs-or-Set-NEJE-Laser-Module-2-In-1-Adjustable-Variable-Focus- Lens and Fixed Focus-Improved-Laser-Air Assist-Laser-Engraver-Machine-Laser Cutter-3D-Printer-CNC-Milling-Banggood-Banggood-World-Exclusive-Premiere-p-1785694 .html?cur_warehouse=CN
Seems, unsurprisingly, 40W is “marketing” but found another link to something that looks the same, they claim 15W optics.That’s fine.
https://neje.shop/products/40w-laser-module-laser-head-for-cnc-laser-cutter-engraver-woodworking-machine
Yes, very knowledgeable about the marketing strategy, but curious how it would actually do.Even if it gets at least a real 10w+ out of the 15 quoted, it’s probably much better than many of the cheaper options out there.Interested to see how well their beam combination works.
The effective output of about 7W is the maximum you will get with the blue diode without overdriving or pulsing (the average is still about 7W).This will only change if the diode manufacturer produces a higher power version.
More powerful laser diodes exist, but they are more expensive and are usually in the near-infrared range for pumping fiber lasers.
Honestly Al; I would get a cardboard box with a fan + exhaust, then cut out a window and install a piece of acrylic.Inexpensive and easy, giving you time to build a complete enclosure out of 2x2s and acrylic.
I think “If you think 3D printed ABS smells bad, you’re not going to enjoy laser cutting” (paraphrasing) is a pretty neat summary.(even a decent exhaust system can only do so much)
By using our website and services, you expressly consent to the placement of our performance, functionality and advertising cookies.learn more
Post time: Jan-26-2022