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• [R] NEJE 60μm lasers

  kelvinA • 3 days ago • 0 comments

  Table of findings

  450nm Lasers

  	A40630	A40640	E40	E80	VF20	K30	P2 33W
  Size (mm)	40*50*85	40*50*85	40*48*145	41*56*113	50*80*80
  Weight	210g	204g	280g	600g	360g
  Input Power	12V 3A	12V 4A	12V 4A	24V 5.5A	24V 5.5A	24V	24V
  Optical Power Min / Max (W)	6 / 7.5	10 / 12	10 / 11	20 / 24	20 / 22	30	33
  Claimed Spot XY (mm)	0.04 0.04	0.04 0.06	0.06 0.06	0.06 0.06	0.08 0.08	0.16 0.19	0.08 0.10
  Power Density  (W/mm^2)	3750	4166	2777	5555	3125	987	4125
  Focus	Adjustable	20 - 70mm	Fixed	Fixed	Fixed	Fixed	Fixed
  Cost (exc VAT)	£60	£132	£110	£312	£200 - 300		£430

  405nm Lasers

  	B30635
  Size (mm)	30*30*85
  Weight	115g
  Input Power	12V 1A
  Optical Power Min / Max (W)	0.5 / 0.6
  Claimed Spot XY (mm)	0.02 0.02
  Power Density  (W/mm^2)	1250
  Focus	Adjustable
  Cost (exc VAT)	£46

  
  

  Research

  So... don't be alarmed (I'm mainly talking to the mirror here) but I've been looking high and low for the ZBAITU VF20 and every listing I find allegedly cannot be shipped to my address:

  

  However, I just found the NEJE E80 which is a 20W laser that currently costs £312:

  

  I lowkey wondered why NEJE didn't seem to make anything more powerful than their A40640, which I didn't pay much attention to since it's a 10W (continuous) laser and I had been looking for 20W ones. I think it was one of the most expensive at the time. The lowest I've seen is under £135 now.

  

  What I didn't know is that NEJE focuses on making sure their spot sizes are 0.06mm or less. For example, compared to a typical 0.08*0.08mm ZBAITU module:

  • the E80 is 0.06*0.06mm, thus a 77% higher power density.
  • the A40640 is 0.04*0.06mm, thus 167% higher. 
    • Yes. This 10W laser has power densities equivalent to an VF20 outputting 27W

  Back to the E80, it seems that the engineers feel like it was best to keep their 20W offering in the oven for much longer than the rest of the industry. Here's some of the quotes (slightly edited for grammar):

  The focal point of NEJE E80 0.06x0.06mm, and the power density reaches 6666W/mm², Compared with *tool 40W module with power density 5000W/mm² (0.8x0.1mm, 8xLD).
  
  E80 is much better than that of similar 20W and 40W laser modules, with smaller focus, smaller angle, XY symmetry... The complexity is more than 3 times higher than that of ordinary 20W modules.
  
  We did not choose 8xLD or 6xLD to release new products relatively quickly for marketing gimmicks.

  I also found it interesting that all 4 diodes are on the same plane and mounted onto a copper heatsink:

  

  Anyway, I found this pic of multiple modules beside each other to get a better idea of size:

  

  I started compiling the table at the top of the log and the laser that stood out the most was the A40630:

  

  This is the smallest laser in multiple different metrics. It's the smallest cost, smallest size, smallest power envelop and a dot size of 0.04*0.04mm, merely 5 microns a side larger than a pixel on one of the 6.X-inch 4K displays, yet still has a power density exceeding the VF20. The thing is that this doesn't agree with the wiki page, which states a focus of 0.13*0.13mm which is muuuch larger. It's literally the only one that's been tested in the wiki:

  Additionally, there's a forum thread from 2023 where one user said:

  I have the E80, and the spot size is about .08 x .10, the same as most 20W lasers. 
  
  The only lasers I have ever seen that actually have a spot size smaller than 0.08 are 1.5W - 2.5W... 0.06 x 0.07ish under the microscope.

  Thus, without 3rd party evidence, I can't merely rely on NEJE's claims. At the same time, Metal Base seems to be getting results from a Laser Tree 30W laser, which has a notably lower power density. They've also got a K10 module that has a quick focus adjustment feature. It seems that 0.03*0.04 can...

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• [R] Screen Search

  kelvinA • 4 days ago • 0 comments

  Table of potential options

  Diagonal Size (in)	Screen Size (mm)	Resolution	Pixel Size (μm)	Megapixels	Transmittance (%)
  		1920 * 1080		2.1
  6	132.8 * 74.7	2560 * 1440 DLP	52	3.7	100
  6.23	134.4 * 84.0	3840 * 2400	35	9.2	7
  6.6	143.4 * 89.6	4098 * 2560	35	10.5	3.7
  7	153.4 * 87.0	9024 * 5120	17	46.4	4

  Going of printer reviews, it seems that most people need to get out the magnifying glass to hope to see details smaller than 30μm pixel size. 600 and 1200 PPI is 42μm and 24μm respectively.

  Research

  So I'm currently planning rough print-volume dimension for the 220L barrel, thus it was, once again, time to look at the current LCD market. I found this ultra high resolution screen on the 19th April for quite the low price:

  

  I thought it would be one of those low prices that wouldn't last (considering I had mainly been seeing 6.23" and 6.6" 4K LCDs for £55 and up), but they're used inside the Mono 4 line of printers, which start at £179:

  

  The smaller 6.Xin LCDs look to come from printers back in 2021. I don't think it's good idea to base a relatively expensive project that could take years to develop on components that are already years old. At £180 (or £200 for the fancier Ultra), the price is quite close to the LCD + Lightsource + Display setup alone. For the SlimeSaver, I have a feeling that a lens matrix light source is much easier to work with than a COB + fresnel. My current top pick is a 6.6in, 72W light source:

  

  However, it seems that the difference in between the 4 ultra and standard Mono 4 is indeed this light source:

  

  Thus, it's quite tempting to just get the Mono 4 for parts.

  Below are the specs for some of the screens:

  

  There also seems to be 2 versions of the 6.6" that has a 7% and 3.7% transmittance:

  

  

  

  I looked into the printers they're in (Mono 2, Mars 3 (Pro))  and they all still have 50mm/h listed as their max print speed. The Mono 4 is listed at 70mm/h.

  In other news, I'm unable to find the projector modules used for either the Anycubic Photon D2 or Mars 4 DLP. Both printers seem discontinued so perhaps there were sourcing issues? Comments under review videos generally imply that 52μm is too large of a pixel size and needs to be 35μm or less (whilst having a larger build size) for satisfaction.

  I assume that the light intensity calculation for the 6.6" is:

  [transmittance] * 72/(14.34*8.96) * 10^3
  = 39.2 mW/cm^2 @ 7.0%
  = 20.8 mW/cm^2 @ 3.7%
  = 15.2 mW/cm^2 @ 2.7%
  

  The Mono 4 states an intensity of merely 3 mW/cm^2 and seems to have a cure time of 3 seconds for 50μm layers. However, it's stated that

  Anycubic Photon Mono 4K [6.23in] can provide = 90% light uniformity and = 27,320 lux power

  which translates to 4 mW/cm^2 using an online calculator. I assume the marketing team just did a conversion at 555nm to get their 27K figure. 

  In their wiki, I found the Mono 4 and 4 Ultra manuals. They're both 24V, but the former is 2.5A and the latter is 3A. Assuming this additional 12W is going into the COB. The standard LED used in matrices seems to be a 3W LED, such as one from Lumixtar:

  

  

  0.7W/(3.4V * 0.7A) = 0.7W/2.38W = efficiency
  = 29.4 % 
  = 30   % (1 s.f.)

  I don't know why the input is 2.4W not 3W, but ok? Thus there's an estimated extra 3.6W of optical power for the COB compared to the matrix. That's an extra 27 mW/cm^2. Only "at least" 0.5 mW/cm^2 makes it through the screen? That's like 2% transparency.

  Alternatively, if we go backwards with the 4% as specified:

  0.003 * (15.34 * 8.7) / 0.04 [w/cm^2 * cm^2 / transmittance]
  = 10.01 W (optical)
  = 33.33 W (predicted input)

   Looking inside the screen replacement video for the Mono...

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• [E1][R] Ready-made, airtight enclosure?

  kelvinA • 04/10/2025 at 11:25 • 0 comments

  I was thinking about the practicality of the current render of the SlimeSaver when there are so many unknowns that could affect how the entire enclosure is designed. I know one thing is certain though, which is that it needs to be airtight. Trying to cut and seal 5 tiles -- as well as a door -- sounds like unnecessary complexity this early into the project. Just look at the difference between the Ultimaker 1 and 2, for example:

  

  While nowhere near as glamorous as tiles, I'm wondering if there's an off the shelf, airtight container that is large enough for a solution. 

  I've read the comments of those that were disappointed in BambuLabs' new H2D and one was that it wasn't a 400x400mm bed or larger. Thus, I certainly want the X axis to be over 400mm at the very least, ideally longer than a side of A3 paper. Other comments believe the add-on laser cutter is of questionable utility inside a 3D printer that needs to be as clean as possible to maintain reliable operation. I also don't have much of a use for cutting sheet stock, so will only include a laser if it's required for conductive circuit traces.

  Some options I found

  The first potential option I found that is in the size category I'm looking for is the barrel below, but obviously it's not ideal for getting things in and out.

  

  Improving on my search strategy, I found a 190L black container. Remember that the materials are sensitive to light so I can't just use something transparent like a fish tank (also, they're £200+):

  

  Depending on the weight, it might be a strategy for the container to instead be the lid, similar to the current MSLA printers. However, there's likely a good reason that large printers don't have one single container-lid like smaller ones.
  

  There are also outdoor storage containers that are much larger and look better, but likely need DIY amendments to make them airtight:

  

  More thoughts on the barrel / drum strategy

  For the aforementioned candidates, it's questionable how well they'd fare being rotated on their side so that the "door" is on the front. When put into scale, the 220L barrel looks like it should be decent space for some kind of preliminary testing:

  

  Due to its shape, and since the goal is proof-of-technology, it would make the most sense to just laminate the resin from one side of the film so that the print can be easily accessed. Additionally, these barrels are obviously the easiest to clean on the inside.

  If the thin film of resin doesn't move regardless of orientation, it may even be possible to keep the barrel as oriented above and the user would pull out the print-bed like it's a honeycomb, thus saving on floor space. Like, even viscous liquids probably would move eventually but it only needs to stay put for under a minute. Such an orientation also reduces the overall amount of motor current merely just fighting gravity (holding up the material cartridges or printbed). Perhaps the bed can be ejected similar to the below monitor lift table from Enwork?

  It seems that pricing on ebay is generally £65+ for a new barrel as seen above, but there's refurbished ones for £55. The seller does note that:

  Please be aware that plastic is absorbent and you may be able to smell the washing solution used to clean the barrel.

  Thus it might not be the best idea to have a plastic container if there's potential that resin fumes could embed themselves. At the same time, it's reported that these containers are made from HDPE, which seems to be the same as resin bottles:

  

  There are also refurb steel drums that were previously used for juice, and since they don't taper on the edges, might allow more room to slide in the printer stuff (which has rigid dimensions, unlike a liquid):

  

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• [A] Name change: SlimeSaver

  kelvinA • 02/08/2025 at 15:07 • 0 comments

  I was considering "SoapSaver" because I wanted it to sound similar to #enSweepen [gd0096], but "soap savers" are actual things that already exist.

  This morning, I remembered the SecSavr Slime, the hotend assembly in #SecSavr Sublime [gd0036], and it didn't take long for me to be convinced to at least try it:

  I also consider S[L³]imeSaver and SLLLimeSaver because of "Liquid Laminate Lithography". 

  The idea behind the name is that the machine is reclaiming the slimy resin instead of letting it sit on the printed part and having to clean it off afterwards.

• [A] "SecSavr" branding is being depreciated

  kelvinA • 10/02/2024 at 15:50 • 0 comments

  This isn't a sudden decision. Instead, it's a feeling that has slowly been chipping away at me.

  For starters, the original reason I thought of the name SecondSavr is so far removed from what I'm trying to do these days. It's like a "Test Drive Unlimited Solar Crown" situation, where I personally think it should just be "Test Drive Solar Crown". Why? Well "the title is getting long" is a reason, but my main one is that "Test Drive" is the brand and "Unlimited" was the name of the game: a new play mode of open world. "Unlimited 2" understandably built on that. Solar Crown, while being an open island game, changed a lot of stuff -- enough that even the developers didn't call it "Unlimited 3".

  Additionally, the project is currently needlessly separated apart. As you may know, #Coaxial8or [gd0144] is currently my furthest-ahead project that isn't "finished" (e.g. like #WK-50 Trackball Keyboard) and I see it a bit like a template of how other projects might play out: Design some ideas, make some prototypes, it grows into the project we see today; that kind of thing. There's also the #Teti [gd0022] kind of project, where you try and make X and then realise there's no off-the-shelf component so now you need to invent Y. SecSavr Suspense is essentially like Coaxial8or but split apart almost like Teti. For example, SuLotion is still a shell after all these months:

  I also want to avoid a Notkia situation:

  

  There's also another 3D printer called SecKit so it would fall into Java / Javascript territory.

  Thus, I'm going to think up a new name that tries to embody one of the reasons I called this printer Suspense in the first place: The suspense in anticipation that Liquid Laminate Lithography can achieve most of the benefits of PolyJet with minimal drawbacks.

  In the meantime, I'm going to archive / delete other projects such as #SecSavr Soapalai [gd0146]. 

• [R] Laser Tree K30 can sinter 316L powder

  kelvinA • 07/16/2024 at 04:12 • 0 comments

  I was looking through the SLS4ALL discord when I found out about the Metal Base project, which aims to specifically print stainless steel 316. 

  Only using 316L metal powder, our extensive testing has shown that using this material in combination with the relatively low laser power does not generate any fire hazard even when used in open air with 20% oxygen content.

  I wonder if this is the reason JLCPCB's only metal print material is 316L. 

  Looking through their YouTube channel, I was able to find out that a Laser Tree K30 -- a 33 - 35W output power laser -- was used. This laser has a spot size of 0.16 * 0.19mm, meaning that it comparatively has the same irradiation intensity as a 0.08 * 0.08mm 7 - 7.4W laser. The price is £375, which was where 20W lasers used to be. Today, the V20 laser, still my most ideal candidate, is only £240. All Laser Tree's modules seem to have the same spot size, which would need to be 95W to match the V20 on intensity. Their current top-end is a staggering 60W, which actually is still priced at the same £/watt as the V20 (it's around £750).

  

  Something to note is that the K30 claims to use 10W less input power than the V20 (120W vs 130W), suggesting that its 6 diodes are more efficient. It actually seems that each 11W uses an additional 24W of input power:

  

  Below is the result of a bottle-opener they printed:

  There doesn't seem to be any video where the part is actually removed from the build plate. I theorise that it's welded onto the plate and has to be grinded off, and then ground again off the supports. Not entirely ideal for a consumer-oriented perspective and why I hope L^3 can do metal + support in a single print job.

  They have an enclosed but not entirely airtight enclosure and use an air compressor (capable of 8 bar continuously without overheating) to reduce oxygen content in the air to 5%, allowing for optimal printer performance.

  The system works by using a CMS (carbon molecular sieve) material in 2 separate air tanks that are switched between filtering and cleaning state. This is called the pressure swing absorption process.

  Their price target is >$6K for the machine.

• [A] Putting design effort into Soapavr (gd0146)

  kelvinA • 07/15/2024 at 07:18 • 0 comments

  I'm planning for the main ground-floor level project logs to be written on #SecSavr Soapavr [gd0146], with the Suspense being the "this could be all the possibilities"-type research project. I just like to have the peace-of-mind that I didn't implement feature XYZ because I weighed the pros and cons and not because I didn't even know it was a valid option in the first place.

  The name could use some work though. It's no longer the shape of a bar of soap nor is a stepping-stone project, so it's now tough to get branding-energy behind it (unlike #Coaxial8or [gd0144] for example).

• [R] Mellow Fly D7: Cheap 7-stepper motherboard

  kelvinA • 02/05/2024 at 05:07 • 0 comments

  Just like with the 8-stepper Bumblebee, I was once again looking around for motherboards because of my Coaxial Hotend project and came across this:

  

  This Mellow Fly D7 v1.0 board is low cost, compact and has all the things that I actually need (UART-enabled stepper ports) and trims out many of the things that I don't (since they'd be on the Manta M8P V2.0). 

  The most notable ommision are EXPn, meaning that I'd only be able to use 1 motor expander (on the M8P). That should be fine, as with 2 Fly D7s and 1 BTT EXP MOT, the printer will have 25 steppers to work with.

  

  It might be useful that CANBUS devices can be connected directly to the board without a separate transceiver.

• [R] BCN3D splits VLM business into Supernova

  kelvinA • 02/03/2024 at 18:42 • 0 comments

  It seems that more tech innovation news happened on Feb 2 than customers getting their hands on the Apple Vision Pro or me getting some test prints from the 4-in-1-out Coaxial Hotend. 

  I've just read on Fabbaloo that a company called Supernova has spun off from BCN3D and taken VLM with them. That sounds good considering BCN3D has been rather quiet on what I believe is a notable technology and the writer, Kerry Stevenson, ended the article with this:

  Someday it may be that Supernova eclipses BCN3D in size, especially if manufacturers catch on to VLM.

  Interestingly, this company is headquartered in Austin, Texas, which I assume is because that's where the US engineering talent pool seems to be outside of California.

  They had an event and here's the things that stood out to me:

  • It runs though as much as 2.5kg/hr.
  • It can print 2 materials in the same layer.
  • They can print in silicone's. The last time I read about 3D printing in silicone's, I heard it was quite involved (involved enough that there are a handful of companies that specialise in 3D printing silicone).
  • The maximum solution price has increased from "under $50K" to "under $100K".
  • They're re-opening the tech adoption programme.

  There was also a short clip of the actual printer printing:
  

  

  The XY resolution is 23 microns, so this must be one very high pixel-count LCD considering its size.

  Now I'm looking though their website and I'm already liking the sounds of the materials. For example, the longer oligomer chains reduces undesirable biological effects:

  

  This is important for wearable electronics, or parts that will experience a notable amount of skin contact (e.g. keyboard keys).

  Then there's the filled materials in 3 flavours: ceramic, metal (such as copper) and fiber:

  

  All 3 of these are materials I'm excited about; ceramics and copper for electronics and then magnetic fibers with Fortify's fiber-aligning tech.

• [X][T] Q8100-60002 uses the AMIS-722402?

  kelvinA • 02/01/2024 at 07:48 • 0 comments

  I did some looking into the printer series' that this scanner is used in, and all but one of them has "optical resolution: 2400dpi". Now this is actually really high, as resolutions in the datasheets that exist online are 200, 300, 600 and one or two 1200dpi. I looked into a handful of other sensors on AliExpress and the printers that they're used in have a 1200dpi scan. 

  The one used in #Magic Frame : Turn Everything into a Touch Area had 2700 pixels. For 216mm of scan length, a 2400dpi scanner would have at least 20,410px!

  Thus, I looked for a 2400dpi CIS chip, assuming that HP wasn't going to invent their own. The only thing I found was the AMIS-722402, with datasheets online (with the sharpest looking to be from Arrow as a PDF download).

  

  14.56mm wide per sensor chip means that 15 sensors would be put together to get over 216mm, resulting in 218.4mm of scanning length and 20,640px.

  By looking at other sensor datasheets, one of the things I noticed is that the communication protocol is rather standardised. There's a pin that starts the scan, a clock signal and, some N number of cycles later, the "video out" (aka sensor data) gets read 1 pixel at a time.
  

  

  For this chip, the clock is typically 2.5MHz but it sounds like the engineers expect the fastest, 3MHz, to be used more.

  So I was thinking to myself "That's all great and all, but shouldn't there be like some kind of examplar circuit in here?" and there was one at the back. I think I'm onto something:
  

  I looked at the pinout here and many of them lined up with the pinouts determined in the past. One of them that was close but not quite was the assumption of "GND but not connected directly to the other GND" pin 3, and this is why:

  

  Technically, the pin can accept 0V, but it's actually expected to use 0.35V and determines the black-level voltage:

  

  Then there are select pins that determine how high a resolution is scanned. Lower resolutions bin pixels together, making them proportionally more sensitive.

  

  I connected the LEDs and found that Pin14 is LED Positive. I expected the entire white section to illuminate, but it's only a strip next to the lens array. I also found out that

  1. Red: Hits the set current limit of 200mA and thus drops till 2.17V
     1. Increasing the current limit didn't seem to make the LED brighter nor increase the voltage, so I tried a lower one.
     2. 2.2V was at about 150mA and slowly climbing
     3. 2.1V was notably dimmer, and 2.0V dimmer still.
     4. Thus, it sounds like I'm going to need a resistor on LEDR.
  2. Green: 5V at 107mA
  3. Blue: 5V at 166mA

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