3D PRINTED LIGHT PAINTING TOOLS

It had been clear to me for a long time what I wanted to print with it. Many of the printed tools make the Light Painter’s everyday life much easier. And at some point I saved the costs for the printer and the printing material because I no longer have to buy tons of gaffa tape 😉

WHICH 3D PRINTER IS SUITABLE?

Basically, printers are first differentiated according to the printing technology. Laser melting, laser sintering, electron beam melting, stereolithography, digital light processing (DLP) and fused deposition modelling (FDM) are common. Actually, only the last two processes are suitable for home use. With the DLP printer, liquid plastic is cured with the help of selective UV light. The FDM printer melts plastic and uses it to build the model on the print bed. This article is exclusively about the FDM printing process. Workpieces from the DLP printer are usually not nearly as mechanically resilient as parts from the plastic melter. Only to print transparent parts would a DLP printer be the better choice, with an FDM printer it will always be milky.

FDM printers are usually built in one of two ways. Either the print head is fixed in the Z-axis and moves in the X- and Y-axis. The movement on the Z-axis is then taken over by the heating bed. Or the heating bed moves on the Y-axis and the printhead on the X- and Z-axis. Both variants have advantages and disadvantages. This does not necessarily affect the print speed and quality. With a few printers, such as the Anycubic Predator, the heating bed does not move at all; all movements are carried out by the print head. This has the disadvantage that the printer is very high. Otherwise, it is certainly a sensible idea that the bed does not wobble around.

Another criterion for me was that there are large communities with many helpful people for the Anycubic and also for the Creality printers. Since problems often arise with 3D printing, especially in the early days, such a community is very helpful in solving them quickly.

Since its purchase, the printer has been running almost continuously; the Anycubic is a frugal workhorse. Some other printers are either divas or bitches or both at the same time. So the perhaps better print quality is of little use to me. How long the printer will last in continuous operation remains to be seen.

The Anycubic i3 Mega is delivered almost fully assembled, after 20 minutes the thing has printed the first object. For an introduction to the world of 3D printing, this is much better than spending two days working on a kit and then realising with frustration that the print results (for now) are crap.

PREPARE THE PRINTER

Before printing the first part, you should adjust and check a few things. First, you should take a look at all the cable connections and the corresponding plugs. Next, check all the screws, especially on the Z-axis couplings. If everything is in order, switch on the machine. When the printer’s operating system has started, you can assume that the power supply, main baird, etc. are also in order.

BED LEVELLING

A cleanly aligned print bed is one of the most important conditions for the success of your prints. The distance between the print nozzle and the bed should be as close as possible to 0.05mm at every point. If the distance is too large, the print object will not adhere sufficiently to the bed and may come loose during printing. If the bed is too high, there is a risk that the nozzle will scratch on the bed. In addition, in this case the filament is widely lubricated. This does not only affect the optics. It could also result in incorrect dimensions of the component. In addition, the component may adhere so strongly that it can only be removed with heavy tools after printing.

You can find hundreds of instructions on this topic on the internet. I was quickly confused by the different approaches, often the important hints for success are missing. So I just did it the way it seemed logical to me. First I screwed the heating bed down a bit so that the pressure nozzle would not hit the ultrabase. That does neither the brass nozzle nor the glass plate any good. Then I moved the print nozzle to the 0 position (“home all” function). Then I switched off the power to the motors via the printer’s control unit (“motor off” function). Then I heated up the heating bed to 60°C, which is the highest temperature I use at the moment. To make it a bit more precise, you could now also heat up the heating nozzle. After all, the bed levelling has to be correct during printing and not when the printer is cold. Both the nozzle and the ultrabase expand slightly when heated. I usually adjust the nozzle when it is cold so that I don’t burn my delicate fingers on the 200°C hot nozzle. Now I put a sheet of paper between the nozzle and the print bed. The paper should not be too thick, normal printer paper with 80 or 90g/m² is suitable. Some people also use a receipt. Now I turn the left front screw until I feel a slight resistance when moving the sheet. If the sheet is stuck between the nozzle and the bed, the distance is too small. If I have to turn the screw more than one turn, I also turn all the other screws one turn in the same direction so that the heating bed remains as straight as possible. It is advisable to level crosswise, i.e. to continue at the back right if the measurement at the front left is correct. If you do this in a circle, it can happen that the glass plate gets tension and makes a hump in the middle. My absolute favourite in the relevant Facebook groups is “My Ultrabase has warped, I need a new one”. You read that at least three times a week. If all four corners are set with the correct distance, you should definitely check whether the measurement is also correct in the middle. If this is not the case, you have to start all over again. It may be necessary to remove the four clamps that connect the heating bed to the Ultrabase for additional safety. If you do not heat the heating bed all the way up, the clips can also remain permanently off. The glue between the heating bed and the glass plate only softens at 110°C.

To be on the safe side, you can now let the bed cool down and heat it up again and then check the distances again. If the heating bed is in its original condition (springs), the height can easily be adjusted by the vibrations during printing. Especially when printing “infill” at high speed and short distances, the whole printer vibrates strongly. The silicone dampers mentioned below can help. Otherwise, after 20 to 30 printing hours at the latest, you should check whether the bed levelling still fits and then, if necessary, realign the bed correctly.

CALIBRATE THE EXTRUDER

To ensure that 100mm filament is actually fed to the hotend when the extruder receives the control command to feed 100mm filament, this should be measured and then corrected in the printer firmware if necessary. If too little filament is fed, there will be more or less large gaps in the print. Too much filament causes dents or similar.

First of all, I heated up the hot end to 200°C. Otherwise the printer refuses to feed filament. Then I pulled the filament out of the Bowden and removed the tube from the extruder. Now I cut the filament flush with the side cutter at the top of the extruder hose connection. I then connected the printer to my notebook. Using software to control the printer directly, in my case Printrun with the Pronterface GUI, I instructed the extruder to extrude 100mm of filament. When it had finished I cut the piece back exactly flush and measured the length. It was only 94.5mm.

I used the M503 command to read out the current value for extruding. The output looks something like this

echo: Steps per unit:
echo: M92 X80.00 Y80.00 Z400.00 E384

So I calculated the new value: 100/94,5*384 = 406,35. With the command M92 X80.00 Y80.00 Z400.00 E406.35 I told the printer the new value and saved it with M500. It is important to enter the value with a dot and not with a comma or to simply leave out the decimal places. To be on the safe side I extruded another 100mm and measured if it fits now.

If you run the I3 Mega with the standard extruder, the value in the original firmware is 92.6, if I’m not mistaken. In this case, you calculate with this value. 100/94,5*92,6=97,99.

You can skip this step for the time being. If the prints are good even without calibrating the extruder, it doesn’t really matter if the value is correct.

WHAT SHOULD BE CONVERTED?

In the relevant Facebook groups you can find the craziest “upgrades” for the Anycubic and other printers. One quickly gets the impression that quite a few people have only bought the printer in order to produce tuning parts for the printer itself so that it then delivers “better printing results”, is quieter and, most importantly, looks nicer. The second-largest group obviously only prints ornaments. As someone who only prints functional parts that he actually uses for their intended purpose, I sometimes feel a little out of place in these groups. I consider most of the upgrades for the printer to be completely superfluous or even harmful, especially the pretty X-Carriage that you absolutely have to print out and attach if you believe the “experts”. These crackpots seriously claim that the cooling performance is improved if you blow from two sides, with the same fan, mind you. The path of the air is longer on the one hand and divided on the other. And the two outlets then blow against each other, so the heat accumulates. As a result, the cooling capacity is much worse than before, and you don’t need a master’s degree in physics for that. And why the original component cooling should not be able to cool the 0.1 to 0.2 mm thick filament seam immediately from one side is completely unclear. In my case, it cooled down immediately and became solid when the speed in the slicer was set correctly. So stay away from this nonsense and other questionable tuning measures.

Basically, I would only change something on the printer if something really doesn’t work (any more). Especially in the early days, you should first gain as much experience as possible with the new printer, try to correct any errors first in the software or by adjusting the printer, and only then think about any upgrades.

Besides the extruder, which I replaced immediately, after some time I replaced the springs under the heating bed with silicone dampers. This saves the frequent levelling of the heating bed. With the springs, the height of the bed is adjusted by the vibrations during printing after some time. The silicone parts put an end to this. However, this is complaining at a high level, even with the springs you don’t have to level every second day, rather after 2 weeks. However, this depends very much on the print object. If there are not many, quick, small movements during printing, i.e. the print bed does not jerk, nothing will adjust.

Because I had the problem with two types of filament that the components could only be removed after printing with a lot of force or tools, I replaced the Ultrabase with a 6mm Pertinax plate. I removed the original glass plate. First I unscrewed the 4 clamps, then I heated up the heating bed to 120°C. At this temperature the glue comes off. At this temperature the glue with which the glass plate and the heating plate are glued comes off. I then lifted the plate off with a spatula. It is advisable to wear gloves, 120°C is too warm even for my rough hands. I then glued the Pertinax plate to the heating plate with 3M adhesive foil.
With the Pertinax plate, printing and removing the printed parts finally works as I had imagined. And by the way, the print bed runs a bit cleaner because of the lower weight. Alternatively, you could also attach a 1mm thick Pertinax plate to the Ultrabase. You could simply fix it with the clamps that are attached to the Ultrabase anyway. However, it is better if you glue them. This prevents “dents” in the plate. Again, I would only buy such a plate if you have similar problems. Most of the stuff also comes off well from the original Ultrabase.

WHICH FILAMENT?

So far I have only printed PLA and flexible material (TPU). Many types are not interesting for me because they are only meant for printing ornaments. Some of the above mentioned types like ASA, ABS or Nylon are difficult to print. With an open printer like the Anycubic, this is usually not possible. For this you would need a printer with a closed construction space so that the temperature does not fluctuate / drop. So if I want to print these materials, I would first have to build an enclosure for the printer.

Basically, you should take a closer look at the pictures of the rolls before you buy. If they are spooled onto the drum in a completely chaotic way, this does not necessarily indicate high quality. In addition, there is a greater risk that the filament will get “jammed” on the reel and can no longer be conveyed to the printer. There goes the 30-hour print. Of course, something like this always happens when the machine shows a print progress of 90%.

PLA – POLYACTIDE

PLA, also known as polylactic acid, is the easiest filament to print with. When I bought the printer, there was a 1kg spool of white PLA in the box. So for initial tests I used this stuff first. PLA has a low density, so the Light Painter ultimately saves his back when he prints his tools with it because the printed parts are light but still quite stable. PLA has a low moisture absorption, a high UV resistance and a low flammability. At about 80°C PLA becomes soft and deforms. So you should not leave PLA printed parts in a car parked in the sun. The abrasion resistance is not very high, so PLA is rather unsuitable for stressed, moving parts, PETG, ABS or nylon are the better choice.

So far I have printed boxes for batteries and the like from PLA. So far, I have not been able to find any major differences between the filaments of different manufacturers. Only the matt black NX2 from extrudr is very brittle and tends to break off when you thread it into the printer. It doesn’t break as quickly in the printed state, but filigree parts will break off much faster than with other PLA. However, the choice of matte black filament is not very large. Some manufacturers also sell matte black filament, but this usually has a silky sheen and is not really matte. For many single-use purposes in light painting, it is very advantageous if the printed part reflects as little light as possible, i.e. is as deep black and matt as possible. The above mentioned PLA from extrudr comes closest to these requirements so far.

Besides the matt black PLA, I have used other colours from extrudr, blue, yellow, orange, neon green, neon yellow, neon orange. These are not nearly as brittle as the black. All the varieties are easy to print. I did not do any test prints. I simply chose the temperatures indicated on the rolls. So if the printing temperature is stated as 185 to 205°C I used 195°C. So far I have had no problems with this ink. So far I have had no problems with this method. Especially when printing functional parts from PLA you can save the printing of so-called Temp-Towers and similar measures to perfect the print. The Temp-Tower ends up in the dustbin. I have also been able to process PLA filaments from other manufacturers using this method without any problems.

TPU – THERMOPLASTIC POLYURETHANE

Polyurethanes have long been used for a wide variety of things, sponges, insulation material, rigid foam, paints, adhesives and what not. Because the stuff is thermoplastic, it can be processed in the 3D printer. TPU filament is available in different Shore hardness grades. In most cases, the manufacturers also specify the Shore hardness as “soft”, “medium” and “hard”. For most light painting tools I use “medium”, for some things the hard TPU. The Shore hardness indicates how far and with how much force you can deform the material, to put it simply. The higher the number, the stiffer the TPU. Prints made of TPU are practically indestructible. In the hard everyday life of the light painter, these tools will probably last forever. However, this also has a disadvantage. If the TPU print has become a little dirty, you can’t just fix it with sandpaper like you can with PLA. And you can only cut off small protrusions with a very sharp knife and a lot of force. Another disadvantage of TPU is that it absorbs moisture. After printing, this is not dramatic. However, if the filament absorbs moisture before printing, the printing results will suffer. So you should always print away TPU as soon as possible after unpacking it.

Very soft material often leads to problems in a printer with a Bowden extruder because the soft material in the extruder or in the tube compresses, stretches or “knots”. With “medium” I have had no problems printing so far. However, there are a few things you should be aware of. Retract, this function of the printer pulls the filament back when the print nozzle moves to another position to change the position without printing anything. If the soft filament is moved back and forth in the extruder, there is a high risk that it will form a kunbbel and get stuck. The “professionals” say: “With TPU always Retratct out, that can’t work”… until someone comes along and doesn’t know that. In any case, you should try it with your own printer to see if it doesn’t work. You should test it with different settings. Basically, the retract speed should not be higher than the print speed, rather half as fast at the most. To avoid funny threads hanging over openings in the print object, for example a cube with a hole in the middle, if you print without retracting, you should switch on “Combining”. The printer then moves around such openings. The print takes a little longer, but it saves you the trouble of fumbling with the threads, which is very tedious with TPU. When printing several parts at the same time, however, combining is of no use. When the printer moves from one part to the next, it will always print an unwanted “seam” between the parts.

Many “professionals” advise not to print TPU faster than 20mm/sec. This may not matter for small parts, but for larger items with correspondingly long printing times, you should at least test whether the material can tolerate higher printing speeds. Currently I print the extruder medium with 50mm/s, the next objects I will print with 60mm/s. Let’s see if that works. Let’s see if that works. Theoretically, the printer could still print faster than 60mm/s, but the manufacturer recommends a maximum speed of 60mm/s. The higher “momentum” means that the material will not be printed at a higher speed. Due to the higher “momentum”, the printer may then no longer hit the position cleanly. Thus, there is a risk that the dimensions of the printed part will no longer be correct and the surface will probably also look quite rough.

Let’s take an example: I print a part with the dimensions 180 x 180 x 60mm. Printing at 50mm/s takes about 24 hours. At 20mm/s the print would then take about 60 hours. The motivation to increase the printing speed as much as possible should be clear.

So far I have had good experiences with SainSmart TPU, TPU V2 from “Das Filament” and TPU medium from extrudr. Most of the other good flexible filaments like Filaflex or Ninjaflex blow a bigger hole in your wallet. I also find Filaflex too soft for most purposes. I haven’t used Ninjaflex yet.

SOFTWARE

The software is quite mature, I have not found any major problems so far. The software is available for Linux, Windows and for the machines with the bitten fruit.

The learning curve for the software is quite long, at least if you want to understand all the parameters and the effects on the print when you change them. The software contains some standard profiles, if I am not mistaken there are three. With these you can try your first prints with PLA even without knowing the effects of changing the “retract speed” and other “secrets”. However, you should take a look at the printing temperature. This should match what the manufacturer of the filament has printed on the spool or written in the data sheet.

I use FreeCAD to create the models that the plastic melting machine will later build on the print bed. As the name suggests, this programme is available for free. Again, the guys have compiled the programme for Linux, Windows and Apple. Since the project has existed for many years, the software is mature. There are workbenches for all kinds of requirements, some you have to install as plugins. FreeCAD is well documented. There is a large community, and you can usually find a solution to your problem quite quickly. Nevertheless, some alternatives to FreeCAD should not remain unmentioned here.

A good online platform for creating 3D models is Tinkercad. Since the software runs in the browser, you always have the latest version, no matter which computer you are working with. The top dog Autodesk also offers good software with Fusion360. The software is free for non-commercial use. However, like Autodesk’s other products, Fusion360 is unfortunately not available for Linux.

If you want to get really deep into the matter and create complex 3D models that can even be animated and much more, you can download Blender. As with FreeCAD, this is open source software. Free downloads are available for Linux, Windows and Mac OS.

TYPICAL FAULTS, THEIR CAUSES AND REMEDIES

THE PRINT OBJECT DOES NOT ADHERE TO THE PRINT BED

– The most common cause is a print bed that is set too low (see above Bed Leveling).

– Some filaments simply do not adhere well. In this case, you should switch to an alternative. It is not much use if you can buy the no-name roll for a few euros less than the brand filament, but then print half the spool for the dustbin.

– The printing temperature and/or the temperature of the heating bed are wrong. The only thing that really helps is to try it out, starting with the average specifications of the filament manufacturer.

– The print bed is dirty. Before printing, you should always completely remove dirt, grease and residues from the last print. The easiest way to do this is with isopropanol. In tougher cases, brake cleaner or acetone will help. Larger print residues should be removed with a spatula beforehand.

– The contact surface of the object is too small (picture 1). If I want to print a 20 cm high tube with a wall thickness of 2 mm on edge, it will not hold because the area where the print bed and the object touch is much too small. With a bit of luck, printing with “brim” (menu item “build plate adhesion” in Cura) works. Several lines are printed directly on the outside of the print object, thus increasing the contact area. Otherwise, it only helps to change the 3D model so that it can be printed.

Many “experts” also have many other “ultimate” solutions on this topic if the material does not want to adhere to the print bed. Mum’s hairspray is generously spread on the print bed and the whole printer is covered with the sticky stuff. Others smear the print bed with a plaster pen or stick painter’s masking tape on the bed. I advise against such things. It usually does more damage than good. Especially the application of hairspray should be avoided if you want to enjoy your printer for a while. If you have levelled up properly, such things are unnecessary.

If the above points have not led to success, you can roughen the print bed with sandpaper to increase adhesion. However, since some filaments, especially flexible ones like TPU, can only be removed with great force after printing, you should think twice before doing this.

If you use a Pertinax plate as a print bed, however, hardly any material will adhere if you do not roughen the surface a little because Pertinax is as smooth as glass. I carefully and evenly dragged 320 grit sandpaper over the surface. First, as straight as possible, from left to right and then from bottom to top. It is essential to wear a dust mask when doing this. Pertinax dust is suspected of being carcinogenic. Apart from that, you won’t be able to get the disgusting stench out of your nose otherwise.

Most of the above points, especially the correct bed levelling, also apply to the reverse case, where the object can only be removed with a lot of force and tools. Ideally, you simply remove the printed object from the print bed after it has cooled down.

NO FILAMENT IS CONVEYED

– Often the filament is simply of poor quality. Deviations in the diameter “clog” the extruder or even the filament sensor. Then there goes the 30-hour print. You can’t necessarily put this down to the price of the filament, but I advise against no-name filament. If you have found a good filament, you should buy it the next time and not change because of a few euros in savings.

– The extruder is set incorrectly. The titanium extruder of the Mega S has a sell screw. This adjusts the pressure with which the two rollers in the extruder clamp the filament. If the pressure is too low, the filament slips through. If the pressure is too high, there is a risk that the filament will be squeezed too much and then jam in the extruder. If the filament is brittle, there is also a risk that it will break.

– The roller in the extruder is contaminated with filament residue or other debris, or the teeth are so worn that the filament slips through. In the latter case, I would replace the entire extruder.

– The print nozzle is clogged. The extruder can push as much as it wants, but if the nozzle is blocked, no filament will come out of the front. In this case you could try to unclog the print nozzle, but at prices of about 1€ I would rather screw in a new nozzle. The reason for clogging is usually that filament residues burn in the nozzle. The nozzle heats up for a long time without filament flowing through it.

PRINTING DOES NOT START OR STOPS

This can have a variety of causes. A defective temperature sensor, the cable from the heating bed has broken off, one of the fans is on strike, the SD card reader has given up the ghost or even a defect in the mainboard are conceivable. In such a case, the first thing you should do is insert another memory card into the printer. In most cases, such problems are caused by the Chinese folders and files stored on the original card.

I will not go into problems that are more of an optical nature, such as slight offsets in the outer wall or the like. That would clearly go beyond the scope.

LIGHT PAINTING TOOLS

What the light painter cannot buy, he builds himself. And even if one or the other light painting tool is available ready-made, you might find a better solution for yourself. Somehow that is part of light painting, at least for me. Anyone can buy one 😉 Let me give you an example. I use several torches with a side switch, such as the Fenix PD36R or the magic lamps from Ryus Lightworks. If you put such a lamp into the usual adapters from the various light painting shops, you can’t reach the switch, at least not in such a way that you can operate the lamp safely. So I printed out shorter adapters for such lamps myself. These adapters only fit exactly one lamp and cannot be used universally like the commercial adapters. I need a different size for each type of lamp. But in return I can control this lamp during the light painting and don’t always have to pull it out of the adapter to change the programme. The other side of the adapter fits all kinds of self-made tools as well as the tools from the Light Painting Paradise. The small round colour filters from Light Painting Paradise fit into the adapter on this side. I printed the adapters from black SainSmart TPU. I also printed some diffusers and other light shapers in transparent TPU.

The possibilities are almost endless. Especially from transparent TPU you can print the most different light shapers. The material is milky after printing. This makes the parts shine softly and evenly. Light painting tools made of TPU are ideal for everyday use because they are much more robust than tools made of acrylic or other rigid plastics.

Apart from the light painting tools mentioned above, I have printed a few other things that simplify the life of the light painter, such as the battery boxes seen above, boxes for the safe transport of some torches, luminescent markers for the tripod and much more.

I still have many ideas, or even finished 3D models, in the pipeline. The printer will probably have to work for quite a while.

CONCLUSION

A 3D printer is a very useful tool for the Light Painter. I wouldn’t want to do without it. But where there is light, there is also shadow. Before buying such a marvel of technology, you should think about whether you really have enough desire, time, technical expertise and manual skills to operate such a printer permanently. Before you can print any desired object with confidence, it takes a lot of time to get used to it. Many metres of filament will end up in the dustbin as misprints in the early days. And in addition, every 3D printer requires a greater or lesser amount of maintenance. Levelling the bed again, greasing the bearings, checking whether all screw connections are still tight, replacing defective or worn parts – there is always something to do. Now that I’m writing this, I should also do some of the things I just mentioned with my printer, then maybe this terrible rattling will stop again. I’m off then…

Always enough filament on the roll

Sven

Sven Gerard

Sven Gerard, Jahrgang 1969, geboren und aufgewachsen in Berlin. Er fotografiert seit frühester Jugend mit großer Leidenschaft. Neben dem fotografischen Erkunden zahlreicher beeindruckender verlassener Orte, widmet er sich seit mittlerweile 10 Jahren intensiv dem Lightpainting. Sein umfangreiches Wissen teilt er auf seinem Blog „Lichtkunstfoto.de“, weiteren Publikationen und in seinen Workshops. Darüber hinaus organisiert er Veranstaltungen zum Thema Lightpainting, wie „Light Up Berlin“. Gerard lebt gemeinsam mit seiner Lebensgefährtin in Berlin und hat einen erwachsenen Sohn.

Sven Gerard was born in 1969 and grew up in Berlin. He has been a passionate photographer since his early youth. In addition to photographically exploring numerous impressive abandoned places, he has been intensively involved in light painting for 10 years now. He shares his extensive knowledge on his blog ‘Lichtkunstfoto.de’, other publications and in his workshops. He also organises events on the subject of light painting, such as ‘Light Up Berlin’. Gerard lives in Berlin with his partner and has a grown-up son.