Alvaro Rodriguez

Interesting topic indeed! While we are used to measure the printer performance on objective data, in the paper the smaller the resolution the better always, this uses to turn into a subjective matter when this also uses to depend on its impact on the actual print and the end-user preferences often. If you ask me, I would say that current mono LCDs 0.050mm resolution is a rather effective one covering almost everything you may want to print, from tiny and fine parts to bigger and much detailed figurines and busts. And combining the 0.050mm resolution with the matching 0.050mm layer height delivers a much convenient comprise between surface detail and printing speed too so we are good to go. Do not led the specs to mislead you. But, there is a but always because that´s not all. The print geometry and shapes also play here. Organic shapes use to be more forgiving than geometrical / mechanical ones often. And the scale is also relevant. In the case of the layer steps, the bigger the print the less relevant they use to be in example. I use to print small 72nd or 48th scale parts. For me the resolution and the layer step uses to be relevant always and I can notice its impact in my prints. So I´m pretty sure that a smaller resolution printer (matched with a lower layer height) should deliver better prints for my needs. Now, for rapid prototyping, I use to print at 0.050 layer height but for some parts I decrease it for having a smoother surface in example. Do not get me wrong, 0.050mm resolution is far enough for having all the tiny and fragile details I would need (no regrets in this area) but a smaller resolution printer would also give me a smoother and more detailed cross section too. These jerrycans are 72nd scale... not bad for a 2K printer. Funny enough, a few days ago I test printed a rather big –for my standards- 1/24th scale wheel prototype at 0.050mm layer height and I would say that was the best wheel I have ever printed, no matter that layer height and printer resolution, just because the bigger size minimized their impact in the actual print. It looked perfect! So far I have been resin 3D printing for a couple of years using the cheapest 3D printers out there and I have zero regrets, quite the opposite. And while I would love to give it a try to one of those 4K or 8K printers I´m not in the urgent need of switching for a more precise one, no matter I positively know I´ll do in due time. But fact is that every time I see what is in my 2K mono build plate after a print run my jaw drops the floor like day one actually. I think that this tech is already mature enough for delivering a more than reasonable surface finish and detail good enough for anyone... and it´s faster than scratchbuilding! Yes, there is some room for improvement in resolution but if that´s relevant and a must have for you it is a question linked to what you will be printing in the first place. Not necessarily a higher resolution printer will deliver better prints for your needs. Regards! Alvaro

Gents. Past weeks I have been updating my Cults3D page with a few freebies more for the small scale AFV modeller. Just for the record, I´ll repost the first ones just because I have redone all the artwork including pics of the prints for you all to see opoosed to the previous containing images of the CADs. This should help for having a clearer idea of how those designs are. Now what you see is what you get. Regards! Alvaro

But after the Mars3 and the Photon Mono 4K, things are still hot in the small factor LCD field. Now Phrozen comes with a new Sonic Mini... 8K, with 0.022mm pixel resolution. It´s a 7" LCD and, from the promo pic, we can also see a double lineal rail and a robust buildplate carriage unlike the weak one in the SM4K. To be released mid october via the usual trend of preorders, early birds and the like. Regards! Alvaro

And yet another contender in the small factor 4K arena. Anycubic Photon Mono 4K. 6.23" 4K LCD with 0.035mm resolution on par with the Sonic Mini 4K and Mars 3. Already out... but for their home market -China- for now. It is supposed it should be available for the rest of us fall this year. The external appareance is a 2K Mono but there are some nice improvements here and there besides the 4K LCD. A much welcomed protective clear sheet for the LCD, adjustable UV power and a laser engraved buildplate (BTW, they are also delivering laser engraved build plates with their Mono X and with the incoming Ultra). Regards! Alvaro

Hi Looks like Anycubic is renewing the line at some extent. While the DLP Ultra has to be seen on the shelves yet (first units won´t be delivered until early 2022), they have also silently launched a small factor 4K printer. The Photon Mono 4K is out already... but for their home market only -China-. It´s the upgraded version of the 2K AC Photon Mono but with a 0.035mm 6.23" mono 4K LCD, so the printing quality should be on par with the Sonic Mini 4K and the Mars 3. It is supposed they should launch it for the rest of us late this year. We´ll see... but for me the more the merrier always. Exciting times. Regards! Alvaro

I´m with you here @Eivind Lunde and I also believe in the power of the communities and freesharing. We all are well aware how that works successfully for many other areas that I see no reason we modellers could do the same soon. Once more, I also have zero complaints regarding those wanting to have some (well deserved) return for their hard work. Internet is such a big place that there is room for everyone... including the bad guys wanting to take advantage of your hard work. BTW on a side note I had been contributing to some mods development in Nexus some time ago and I have to say that was a lot of fun but that required countless hours of hard work. Again, zero regrets actually. The fact that thousands of users could enjoy such collaborative work (for free) made it a truly rewarding experience. Regards! Alvaro

BTW, Anycubic also has a new model in the works, the Photon Ultra. No further details yet but that they are switching from LCD to DLP (the same system you may find in Wanhao printers in example). I have no idea if there is any afordable DLP projector delivering true 4K resolution so we will have to wait and see for knowing the actual specs.

Elegoo will be entering into the small factor 4K printers arena with their Mars 3. 😀 No ETA yet. Knowing the supply issues Eleggo has with their Saturn I would not hold my breath for having these M3 available anytime soon but it´s good to know that now that the trend is bigger is better that there are other manufacturers interested in releasing small factor printers with higher resolutions. The more the merrier always. 👍 Exciting times indeed! Regards! Alvaro

Ops, I hope it´s evident but I forgot to say that I deleted on purpose all the dimensions and constrains in the sketches just for having cleaner images! 😅😆 Regards! Alvaro

Mike, that bowser is a candy! Excellent! There you go a SBS. You may see that I´ll be working with a half tyre and an elemental tread for simplicity. Notice also this is the workflow that Tony explained in his earlier reply. Here we got the tyre cross section. Using revolve we create to different bodies. One for the tyre body. And another for the running band So simple: The resulting body is as follows: And now the running band simple enough! Using the previous bodies we have the (half) solid tyre But we want to mantain them as individual bodies for now because what we are going to cut is the running band only. We create a construction plane on top of the tyre. and then we create a sketch for the tyre tread using that new plane. As you may already suspect, now we can cut the running band with the tyre tread using extrude. And with the help of a circular pattern we can copy the cutout faces as required. The resulting running band is as follows And if we now add the tyre body, we are done. But let´s take a closer look at how the treads are now in the sidewalls, something may look off depending on the tyre you are designing but in most tyres the raised tread uses to be squared and not angled like this. There is a simple trick just adding a taper angle when using extrude for cutting. See how the sidewall looks now. And this is the final product. These simple steps will help you to do a ton of different tyres, no matter how much complex the tyre tread may look. It´s just a matter of iterating until you have the desired result. As you may see, in this sample we have keept the required steps to a minimun but you can introduce any changes based on your preferences. In example, you may want to generate a true body for the tread and use the splitting tool for making the cut. If that´s the case, you can also use the draft tool instead of the taper angle in the extrude. There are plenty of paths and options here so adopt what´s best for you always. Regards! Alvaro

Just for the record, I also use design in scale always. While rescaling a 1:1 desing to any given scale is not an issue for the software, this is misleading because rescaling from 1:1 can lead to actual printing issues often so that´s not how this works. The problem here is that you can reach printing constrains and the model cannot be printed safely. Details (no matter in positive or negative spaces, like a rivet, a plate or a groove) can be too small, thin or fragile to be printed. So there are some minimun dimensions we should not go below for ensuring our model is printable. Those minimun dimensions will depend not only on if the print is robust enough but on the printer acurracy too. Fact is that this is not unique to 3D printing but to any other manufacturing process applied to scale modelling but we use to think that these tiny -and basic and cheap!- miracle machines have no limits many often ! 😅😆 Regards! Alvaro

On the resin cleaning topic, note denatured alcohol -that uses to be ethanol- works flawlessly with most of the resins out there (not saying that´s the recommended choice by some resin manufacturers actually). No matter it had a low percentage of other ingredients -like IPA or even MEK-, uses to have zero adverse effect on the prints, quite the oposite. Another option is acetone. Far more aggresive but works like a charm. Just ensure you to do not let you part into the acetone bath for too long. But that´s not a problem because the cleaning is much faster. No matter the medium, a two baths cleaning uses to be the best, easiest and safest path for those without a curing station. That ensures the most of the uncured resin goes away with the first bath and the part comes pristine from the second. You can use acetone for the first and IPA or ethanol for the second (or both). Regards! Alvaro

If you are thinking in testing these resin 3D printing waters on a budget I concur with the previous comments and the contenders in the small factor arena are the Anycubic Photon Mono (and not the SE) and the Elegoo Mars 2 (and not the 2 Pro). I want to remark the low cost factor because for anyone wanting to discover how this tech works that seems to me the smartest path for gaining some first hand experience with this amazing tech without breaking the bank. Both feature all the "must have" ticks in the checkboxes you may need. Rather capable 6" 2K monochrome display delivering very sharp and precise prints, linear rail and a good UV lamp (led array in the case of the AC Mono and a fantastic COB led in the Elegoo Mars 2). And both are really simple to operate. AC Photon Mono is, in my honest opinion, the queen of the entry level mono printers with a hard to beat value for the money. Note this comment is based on AC uses to run special sales in their Aliexpress official store almost every month. Past days this printer was available at a rather ridiculous price of 164eu, free shipping, and shipped from their european wharehouses (UK, DEU, SP, FR, CZ, PL...). One plus -personal opinion here always- of the AC printer is the almost undestructable four screws levelling system for the buildplate. I find this the best and more secure levelling solution. Another thing I like a lot is that it does not include any cooling fan, and this makes this printer the most silent one out there. On the other hand, and this is something quite relevant for me at least, the big plus of the Elegoo Mars 2 is the core. Unlike the AC machines with their proprietary boards, Elegoo printers use Chitu System boards and that´s why Chitubox is their native slicer. Perfect partners indeed! The UV lamp of the Elegoo Mars 2 and Mars 2 Pro is covered by a single lens delivering the best and most uniform light, far superior to any led array. In this regard, the Mars 2 is one step ahead the rest. Other than than, and in terms of actual printing, the only remarkable difference is that the Z axis is 10mm higher in the AC printer. 160mm for the AC Photon Mono vs 150mm for the Elegoo Mars 2. This makes no difference to me but others opinion may vary, of course. None of those printers include air filtration for the resin fumes. That´s not a concern in my experience and I much prefer to have a printer without air filtration actually. That means one fan less and a more quiet operation always. The price difference between them is not that high so the final decision will be driven by personal preferences mostly. But no matter which one you would chose, you can´t go wrong with any one of those two printers. Of course, there are more small factor printers out there but do not let these two low end, entry level printers mislead you. Both are capable machines and both deliver some good and solid printing. Regards! Alvaro

Mike, if your print is falling off the support trees I would say that the usual suspect here is one of the following: too weak (thin) supports or too few supports... not saying a combination of both. In the slicer, and using the slice selectors, doublecheck how your print is growing. At some point the suction force is strong enough for taking the print off the supports. This uses to be when you got the maximun cross section paralell to the builplate. On a side note, and as I have already said before, while I also love to see those prints "ready to use" off the build plate requiring the minimun supports tress I see that many often thats a common cause of failed prints. And that´s why adding one support more -and removing it later- is not an issue for me. Removing supports from the print should never be an issue for a modeller used to remove kit parts from the sprue trees. Mark, the point of the pedestal is not for making the cleaning easier but for providing a solid base for the part. In fact it is easier to remove supports than to remove the pedestal but the pedestal is far easier to place and use than placing a lot of supports in the lowest part of the tyre for ensuring it will print fine. When you are not in the need of a fully detailled (and printed) running band -that could be the case of a spare wheel often- a custom base is quite handy. And into the wheels topic there you go another sample I´ve been printing past days. These are some wheels big enough for making this approach worthy. Printing the tyres upright provides us a fully detailed running band all around while printing the rims in halves and onto the build plate gives us the sharpest surface detail, a must have when you have tiny nuts and bolts in example. -my apologies for the crappy smartphone pic- The only thing you have to take into consideration here is that you may need to introduce some tolerances in the print for ensuring the wheel can receive the rims but this will depend on the precission of your printer. In this case I had to reduce the diameter of the rims 0.1mm for an almost perfect and very tight fit. Regards! Alvaro

Hi Mike. My printing settings: The normal layer height uses to be that one that matches -more or less- the printer XY pixel size. In the OG Photon I used to work with 0.040mm layer height and in the Photon Mono I´m using 0.050mm AS LONG AS the print does not require to use a thinner layer. If that´s the case I use to work with 0.020 or 0.030mm layers. Regarding the bottom layers, four use to be enough for me, no matter the printer. Regarding the rest of the printing settings -exposures, speeds...- that will depend on your printer and resin setup always. I have no issues in sharing those openly but I also think that what works for you may -or may not- work for me and vice-versa. Then, any shared printing settings must be taken as orientative always and the most reliable way to know the best amd more exact printing settings for your printing setup is running an exposure test. No shortcuts here. Those are rather fast print runs and they provide quite reliable info always. That said, and just for the record, I use 1.6sec exposure for the normal layers and 15s for the bottom ones. My speeds are the quite hight default ones for the Photon Mono -4mm/s lift and 6mm/s retract-, I have adjusted the lift distance to just 4mm lately and I´m currently using a 1sec light off delay too. Supports. Please, note that previous print samples it´s not a matter of scale but a matter of size. smaller objects can be supported using small supports while larger ones may require medium or heavy ones often. I use to work with default supports but adding the ball tip always. And, again, I do not use a fixed size for the ball tips. That will depend on the print and on the available area or surface for placing a support. However, I use to ensure the ball is halfway into the model always and that the tip of the conical section of the support is a tad over the half of the ball size. If I´m using a 0.5mm ball, the tip of the cone should be around 0.3mm in example. Note that here is more a matter of proportions between the ball tip and the tip of conical section than a matter of exact sizes for me at least. My apologies if this explanation is not clear enough. I could take some screenshots of my settings for you to see if that helps. Regards! Alvaro