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Detailed Review Of Formlabs Form 3B Printer

Alongside the Form 3 printer, Formlabs has launched Form 3B which is specifically designed and tested for the dental industry and dental professionals. And with the launch of a new business unit called Formlabs Dental one can understand the dedication and attention the company has given to supporting the dental industry with both printers and materials.  Most features of Form 3B are the same as the Form 3 printer but form 3B supports a wider range of medical and dental resins and also includes expert dental support for customers. Let’s review some features and finally look at what special resins are supported on Form 3B.

Design

The upper body case is transparent-orange in color with a white plastic bottom. The white plastic bottom case distinguishes Form 3B from Form 3 which has a black bottom case.

Low Force Stereolithography

Similar to Form 3, Form 3B uses Low Force Stereolithography (LFS), a new technology that has a flexible resin tank to reduce the peel forces on the layers being printed thus producing accurate and stronger parts.

Build Volume

The printer has a build volume of 145 × 145 × 185 mm which is sufficiently large for printing dentures and dental surgical guides.

Reliability

Form 3B has upgraded hardware for delivering reliable prints each time so that medical professionals can focus on printing and patient treatments than having to figure out any print problems. Form 3 supports a wide spectrum of medical and dental materials allowing the adoption of 3D printing into the ecosystem of dentistry.

Software

Formlabs’ own proprietary Pre-Form software allows for slicing, automatic support generation, configuring all the print settings like layer height, and selecting the material profiles. Pre-Form supports STL and OBJ file formats. Formlabs dashboard offers real-time monitoring such as print status, pause/stop, and gets information for maintenance.

Control and Connectivity

Form 3B has a 5.5” LCD touch screen control + connectivity options of Wi-Fi, Ethernet, and USB. Formlabs dashboard allows enabling SMS/Email notifications for alerts.

Specifications

Technology: Low Force Stereolithography (LFS)

Build Volume: 145 × 145 × 185 mm 

Layer Thickness: 25 – 300 microns 

XY Resolution: 25 microns 

Laser Spot Size: 85 microns 

Biocompatible Materials: Yes

Expert Support for Dental Professionals Included

Formlabs has added Dental Service Plan (DSP) which can be subscribed to for having an entire dedicated customer service team and Certified Dental Agents reachable via phone or email. The plan also includes personalized onboard training to help practitioners bring the best out of the printer. 1 year premium subscription to this service plan is included with a Form 3B printer.

Special Dental Grade Materials

Formlabs has a total of 50 dedicated material scientists working to add more dental and medical-grade materials. Below are some of the dental-grade resin materials (with variants in each) that are compatible with Form 3B printers. Formlabs has acquired Spectra (a company specialized in making material resins) which is a great step forward for strengthening the availability and compatibility of resins with the printers.

Denture grade resins- Suitable for printing denture bases and denture teeth. Both have separate resins 

Biocompatible resins – Suitable for printing clear and transparent occlusal guards and splints.

Surgical Guide resins – Suitable for printing surgical guides for aiding the implant surgeries such as locating and positioning the drill tools.

Castable Wax resins are suitable for printing the patterns of crowns and bridges later used for casting metal crowns and bridges using lost wax casting techniques.

Post Processing Kits

Form3B Core Package comes with a basic Finish kit alone. But Form Wash and Form Cure can be purchased separately and they are compatible with Form 3B.

All in all, Formlabs Form 3B is a great professional 3D Printer that comes at an affordable price point. At THINKFAB, we offer Form 3B 3D Printer at a high competitive price. Click here to request for quote.

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Detailed Review Of Formlabs Form 3 3D Printer

Formlabs has been the brand that is well known for its stereolithography (SLA) printers and the Formlabs Form 3 is chosen to be the best resin based 3D printer of the year 2020 and it is no surprise once all the design, interface, print quality and resolution are looked in detail. Formlabs printers have evolved and Form 3 is the successor to the form 2. Let’s take a detailed look at the salient features.

Design

From design perspective the printers has an orange outer body with a black plastic base. The orange body makes it a see-through as well as UV-light blocking at the same time helping you to see what is printed while safeguarding the print and resins from ambient light.

High Precision Laser

The Laser spot size in Form 3 is much smaller and finer (80 microns) than the Form 2 (140 microns).

Printing Fine Layer Heights

The Printer allows you to choose between layer heights of 0.025 mm to 0.3 mm. The least possible layer height being 0.025 mm makes it one of the finest printers to produce very fine detail prints.

Performance

Prints are really smooth and geometries that have intricate details are possible. The easy to remove supports generated by the software allow for very tiny contact between the part surface and the support structures leaving no marks on the part. Prints like the gears and threads are possible. Form 3 prints are reliable and the software automatically picks the correct setting when the resin material is selected. Surface finish on the prints is very good with no visual layer lines making it well suitable for creating master patterns for other casting applications. Standard grey resin gives the best results in terms of surface quality than clear and transparent resins that may need careful post processing.

One point to note is that the printing speed is not very fast as compared to more commonly known FDM printers that print out of wire filament. But resin printers are generally meant for producing fine layer details than faster print volumes so speed is always not the criteria for Stereolithography printers.

Prints from Form 3 Grey Resin
Prints from Form 3 Grey Resin

Controls

It has a full touch screen console system that makes operation and control easier. Printer has Wi-Fi, Ethernet and USB connectivity options for file transfer and print job monitoring.

Build Volume

The printer has a build volume of 145 × 145 × 185 mm. Although not as big as other technology printers like FDM printers, this build volume is not too small for precision parts.

Software

Pre-Form is the software that Formlabs developed for their SLA printers that has all the settings and options needed for creating the support materials, selecting the layer resolution and preparing the print. Formlabs dashboard can be accessed within Pre-Form for track ongoing print jobs; queue/pause/cancel prints or to get notifications for maintenance.

Formlabs Pre-Form Software interface

Materials

Form 3 supports a wide range of draft, engineering, jewelry and medical grade resins. Each resin comes with the cartridge. Most resins are tested for strength that is same and uniform in all 3 directions (Print X, Y and vertical build Z) which is one of the main advantages of printing in Formlabs printers if parts need isotropic properties . One downside being that Formlabs does not support refilling the resin and hence the entire cartridge has to be replaced after the resin is exhausted but this should not be a problem to ensure no dust enters the resin chamber or contaminate the print. Left over remains of resin needs to be washed as per proper chemical waste stream and the plastic case of the cartridge needs to be disposed as per local plastic waste guidelines.

Post Processing

Form 3 comes with the finish kit that has tools for safely removing the part and also has washing tools like tray and basket for washing excess resin in IPA (Iso Propyl Alcohol). Form 3 does not come with dedicated post processing equipment for curing the parts under UV light for better strength and have to be purchased separately. However, the Form 3 Bundle does come with Formlabs Wash for automatic washing and Formlabs Cure for curing the parts.

Finish Kit included with Form 3 printer

All in all, Formlabs Form 3 is a great professional 3D Printer. At THINKFAB, we offer Form 3 3D Printer at a high competitive price. Click here to request for quote.

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Detailed Review Of EinScan-SP 3D Scanner

The EinScan SP is an upgraded version to the previous version SE with some upgraded features that is featured by many experts as one of the best desktop 3D scanners. Although both SP and SE scanners look exactly the same, the SP has some advantages over SE. Let’s see what is included with SP.

Faster Scan Speed

The EinScan-SP has a faster scanning speed almost 2 times faster than the SE. This is particularly suitable when multiple parts are needed to be scanned in less time. But the underlying point is that SP recommends a much higher RAM (16 GB) and GPU.

Metrology Grade Accuracy

The EinScan-SP can achieve a better scanning accuracy of less than 50 microns size wise making it suitable for metrology usage. This is a vital aspect when often the need of scanning is to rebuild an accurate 3D printable model from the scan. SP uses a slightly better calculation algorithm to achieve the accuracy (with the same 1.3 Megapixel cameras as the SE) but a dedicated GPU is required for ensuring the accuracy is met.

Larger Scan Size

In auto-scan mode both SE and SP scanners offer a scan size of 200x200x200 mm. But in Manual mode, the SP can scan up to 1200x1200x1200 mm and this is because SP uses 16 GB RAM.

Optimal Calibration and Scan Options

EINScan-SP provides calibrations and alignment options for getting optimal quality scans.

Software

The EinScan software allows selecting the scan mode (bright, dark, bright&dark) and the software automatically adjusts itself for the lighting type without having to guess the right settings for the ambient lighting. Although it is recommended a darker environment gives the best resul in capturing the object with minimal distortions.

The Einscan software provides scan data file export formats of.ASC (whole), .ASC (separate), .STL, .PLY, .OBJ, .P3, and .3MF. 

All in all, EinScan-SP is a great professional 3D Scanner that comes at an affordable price point. At THINKFAB, we offer EinScan-SP 3D Scanner at a high competitive price. Click here to request for quote.

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Detailed Review Of EinScan-SE 3D Scanner

Einscan-SE is one of the top picks of 2019 for portable and reliable high end 3D Scanners and still remains a marvelous machine with decent price tag. If you need a dedicated 3D scanner that serves the job of getting reliable 3D scans of small to medium sized objects then Einscan-SE could be right for you. Let’s have a more detailed look at the features and scan quality.

Technical Properties


Einscan-SE uses the foundational 3D scanning technology called structured-light detection and has a scan volume of 200x200x200 mm with the auto-scan feature. Dimensional accuracy of 0.1 mm to the actual object. The scanner is also capable of detecting textures and colours decently well. However general limitation is that objects that are high glossy, transparent or black are prone to scan data dispersion. For larger objects up to 700 mm³ the fixed scan feature can be used can later be easily aligned and soothed over with the EinScan software.
Depending on the size of the object, you might find it more comfortable and easy to work if the scan head is mounted on a tripod stand. This also ensures the scan is sturdier.

Assembly

The EinScan-SE package comes with the scanner, a turntable for 360° scans, a calibration board, and a stand to connect the scanner head and turntable. The turntable is easily linked to the scanner head, which plugs directly into a power socket. You can then connect the scanner head with the supplied USB cable to your PC. You will need to calibrate the scanner to optimize the scanner’s performance. The calibration process doesn’t take more than a few minutes but could vary depending on the PC being used.

Operation

The turn steps can be adjusted from 8 to 180 steps. The turntable rotates in steps to complete a whole 360 degrees of the object. Higher steps make sure all the details of the object are captured while also increasing the scan time. But for simpler objects, using lower steps makes the scan faster. For better results, 2 different scans with varied light settings can be taken and merged in the software. The scanner also supports HDR mode where the object is illuminated for a bit longer and finer beams of light is used for better scan quality, but it takes a bit longer time to scan in HDR mode. Ideally for best possible scan results the environment should be dark avoiding a bright light directly falling on the object and the scan head. Scanning in bright light conditions is very difficult (the scan leads to quality dropping below recognition) hence wrapping a large cardboard behind the object and the scan head is advised to block outside light and if the room had light entering from the window, light can be blocked by shutting the blinds.

Software

EinScan Software

The EinScan software has to be purchased separately and has an easy to use interface. Mesh generation time is highly dependent on the processor power and we recommend using high end processor PC that have a clock speed of at least 3 GHz and a RAM of 12 GB. Typically a mesh of around 2 million triangles could take a time of 15 minutes got generation. A point to note is that there is no save option and the scanned mesh will be auto-saved into the project name folder given when the software is loaded. Mesh data can be exported into STL, PLY and OBJ formats thus enabling to 3D print the scanned object if needed.

All in all, EinScan-SE is a great professional 3D Scanner that comes at an affordable price point. At THINKFAB, we offer EinScan-SE 3D Scanner at a high competitive price. Click here to request for quote.

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Detailed Review Of Raise3D Pro2 Plus 3D Printer

Raise3D Pro2 Plus

The Raise3D Pro2 Plus is one of the few professional large-format 3D printers. It offers a spacious 305 × 305 × 605 mm build volume, which puts it in competition. The Raise3D Pro2 Plus is pitched at labs, entrepreneurs, manufacturing and prototyping companies. It’s not a typical maker’s machine to tinker with as it’s meant to deliver results. Let’s dive in for what this printer has to offer the best.

Gigantic Build Volume

Raise3D Pro2 Plus Build Volume

The printer has a vast build volume of 305 × 305 × 605 mm making it one of the largest printers by build volume in z direction. Also the printer weighs a whopping 52 kg and handily, the inbuilt caster wheels let one move it around. Due to the weight it is not suitable as a table-top or desktop printer.

Enclosure

Raise3D Pro2 Plus enclosure body

Fully enclosed design makes sure a more uniform temperature is maintained in the build chamber so that printing materials like ABS and HIPS has no problems. The enclosure also makes the Pro2 Plus safer for beginners to work with.

Rugged HeatBed

Raise3D Pro2 Plus Heatbed

The print bed is now aluminum with a proprietary BulidTalk surface sticker for better adhesion.
And the table is now fixed with magnets and screws. Therefore, there is no more clothespins for the extruder to snag on.

Dual Print Head

Raise3D Pro2 Plus dual print head

Dual Extrusion printing is one of the most important features of this machine. It’s not only about dual-colored prints (which can be nice, of course), but more about the use of soluble or break-away materials. The print head is sturdy and big, capable of positioning the print-head to reach a resolution of astonishing 5 microns or 0.005mm in the Z-axis. The most important upgrade in the Raise Pro2 3D printer is the extruder. In earlier model N2 printer, even if the nozzles were positioned correctly in height relative to each other, there was still a danger that the inactive nozzle could “knock down” the model. But with the Pro 2, this problem has been eliminated. The printer has a system of rising nozzles. When printing, the inactive nozzle rises up a few millimeters just enough to prevent it from interfering with the active nozzle.

7inch Touch Screen

Raise3D Pro2 Plus 7inch touch screen

Touch screen control is a nice feature to have and Raise3D Pro Plus has a large 7 inch screen for easier interaction and better experience.

All in all, Raise3D Pro2 Plus is a great professional FDM 3D Printer that comes at an affordable price point. At THINKFAB, we offerRaise3D Pro2 Plus 3D Printer at a high competitive price. Click here to request for quote.

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Detailed Review Of Raise3D Pro3 Plus 3D Printer

Raise3D Pro 3 Plus 3D printer

Raise 3D Pro-3 Plus is a revised and upgraded version of the previous version Pro 2 Plus. According to the company, the Pro 3 is claimed to be a more intelligent state of the art printer than its predecessor. While the Pro 3 Plus is a really great printer on its own with dual extrusion capability and a large build volume of 300x300x605 mm like the Pro 2 Plus, let’s see some additional features of the Pro 3 plus.

Material Compatibility

Pro 3 series printers are capable of printing a much wider range of materials that can melt within 300 degrees Celsius, including PLA, ABS, HIPS, PC, TPU, TPE, PETG, ASA, PP, NYLON, PVA, Glass Fiber Infused, Carbon Fiber Infused, Metal Fill and Wood Fill, among others.

Interchangeable Hot Ends

Independent modular extruders mean that you can install a variety of nozzles. Abrasion resistant nozzles can be used when printing harder composite fiber filaments like Glass Fiber and Carbon Fiber. And nozzles of different diameters can be used as per the print speed and resolution requirement enabling you to fully leverage the larger build volume to print large models in less time. The click and lock mechanism makes these hot ends easy to change without any tools.

Auto Bed Leveling

Though the printer is already equipped with factory calibration, the added Auto Bed Leveling feature makes sure that the printer always delivers reliable prints in a production setup. This also eliminates calibration times by a significant amount.

Air Flow Manager

It is vital for the temperature inside the chamber to be stable to ensure that the part does not warp due to varying environments. This is possible when the heat retention and heat dissipation are managed well. The Air Flow Manager with HEPA air filter is exactly added for this purpose ensuring better heat dissipation and also cleaning the air.

Flexible Buildplate

Flexible build plate makes the part removal effortless and does not damage the part.

Power-loss Recovery

In case any power outage occurs, the recovery system saves the print status so that printing can be continued from the stopped location.

HD Camera

HD cameras enhance the video quality for better monitoring.

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How to unclog a 3d printer nozzle?

Nozzle clogging is one major issue with FDM 3D Printers. When nozzle gets clogged, material won’t get extruded. There are multiple reasons for nozzle clogging. Nozzle clogging can be completely avoided if some preventive maintenance measures are taken. Below are certain reasons for clogging of the nozzle

(a) Inserting a new filament that has lower temperature requirement without cleaning out the nozzle completely

(b) Dusty filaments

(c) Filament stripping in the extruder gear and the filament left in the nozzle

How to unclog the nozzle: There are multiple ways to unclog the nozzle. Below is the detailed explanation of these various ways to unclog the nozzle

(a) Brass wire brush – Use a brass wire brush to clean off any debris / remains from the nozzle. This will prime up the nozzle by removing unwanted particles. Use only brass wire brush and don’t use steel wire brush as steel wire brush can cause damage to the nozzle.

(b) Acetone bath – Thermoplastics dissolve well in Acetone.  So cleaning the nozzle with acetone bath helps remove unwanted particles and unclogs the nozzle. For the acetone bath, first heat up the nozzle to the print temperature of the last material used and then use a wrench to detach the nozzle from heater block. Once detached, keep the nozzle in acetone liquid overnight. This works very well for ABS. If there are other types of filaments, then use heat gun to melt out the remaining filament.

(c) Acupuncture Needle – One other approach to clean nozzle is to use acupuncture needle. Preheat the nozzle to the print temperature of the last nozzle you are printing with and gently insert the acupuncture needle up through the nozzle, push and pull the needle through nozzle for few times to clean the nozzle.

(d) Cleaning Filament – Heat the nozzle up-to 250 degrees centigrade and push the cleaning filament through nozzle until you don’t see any of the old filament coming from the nozzle, then pull out the filament from nozzle and heat it once again to remove the remaining filament from the nozzle and clean the nozzle.

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How is 3d printer filament is made?

Filaments are a vital part of additive manufacturing. It is the main source in FDM printing. As there is rapid growth in industry, the filaments are available in a variety of sizes, brands, materials. The process consists of five steps. Now let us know in detail how the filament is made.

Step 1: Plastic – The first step in manufacturing filament is the preparation of plastic. Crude oil is heated in an industrial furnace during refinement. Main component is naphtha, which is chemically bonded in the reactor. Finally the products are melted and mixed with other products to form plastic. Then the resulting product is known as pellets or resin. Usually plastic suppliers manufacture plastic in white color so that customers may get their desired color when required. Pellets are very inexpensive compared to filaments.

Step 2: Preparation – The second step in the process is preparing the pellets and shaping them. Next they are solidified in order to form string-like structure. Now the pellets are put into an industrial blender and additives are added to it. These additives can be used to add colorants or to determine the properties such as resistance, strength etc.

 Drying -Once the pellets are mixed properly they are moved to the drying section. Generally pellets absorb moisture from the air so they are called as hygroscopic. They are dried around 60°C to 80°C for a few hours.

Step 3: Shaping -The third step in this process is shaping the pellets into a string-like form. This involves both heating and cooling.

a)Heating – First the pellets are fed into a filament extruder which has a heating chamber. Here the pellets are melted into a sticky material so that the desired shape can be obtained. Now the string like material leaves the chamber and then moved into the cooling section with the help of nozzle.

b) Cooling -After leaving the chamber the filament should enter into two chambers. The first is full of warm water which is used to attain rounded filament. The second is full of warm water through which the filament cools and forms a new shape.

Step 4: Spooling -Now it is moved into the spooling section. This is done in order to check whether the filament’s diameter is as per the target diameter. Generally diameter may be 1.75 mm or 2.85 mm. Finally filament is wounded around a spool. After sensing the spool is full, the filament is detached. The same process is repeated.

Step 5:Packaging -The last step is selling the product. Company specific brand packaging is done. Packaging consists of labelling and barcodes for business purpose.

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Overview of various FDM 3D printer nozzles

3D Printer nozzle is one of the most important components of FDM 3D Printers. This is the last piece of item that the material touches before it gets extruded onto the build plate. Previously there was only one type of nozzle – Brass Nozzle (0.4mm diameter). Due to excellent thermal conductivity properties of brass and low melting point temperature & non-abrasive nature of ABS, PLA material, this nozzle was more than sufficient for FDM 3D Printing needs. But over time the application needs of FDM 3D Printing technology grew manifold and so are the needs to come up with different nozzle that can withstand higher temperatures and abrasive materials. In this article we shall look at various such nozzles in detail. Nozzle can be generally classified as per below

(1) Filament Diameter – 1.75mm (or) 2.85mm. There are only 2 standard filament diameters available.

(2) Nozzle Material – Various new types of nozzles are being launched regularly. We have brass nozzle, stainless steel nozzle, hardened steel nozzle, titanium nozzle and many more new types of nozzles are being launched regularly. Here is a quick overview of different nozzle materials

(a) Brass – Brass is the most common metal used for nozzles. Brass can be used to print PLA, ABS, PETG, Nylon, TPE, TPU, PC and most any other non-abrasive materials. Brass has excellent thermal conductive properties and are good for printing standard thermoplastics like ABS, PLA but brass isn’t good for abrasive filaments.

(b) Stainless Steel – A step above brass, nozzles made from stainless steel are good if you want to print a wide range of types of filament, including abrasives. Also stainless steel nozzles are recommended for medical applications.

(c) Hardened steel – If you want to print purely abrasive materials, hardened steel nozzles are what you want.

(d) Specialty materials – Other materials, like Tungsten and Ruby, have been used to make harder nozzles that can stand up to constant abrasion. These are for printing exclusively abrasive materials, and typically cost more than the other options.

(3) Nozzle Diameter – Previously there was only one standard diameter – 0.4 mm. But over time various new diameter nozzles are entering the market – 0.25mm, 0.6mm, 0.8mm

(4) Nozzle Length – We have both longer nozzles and shorter nozzles. Longer nozzles are easy to clean due to proper airflow whereas shorter nozzles reduce heat loss, help in better transmission of heat & also reduce the positioning error. Also, the material consumed will be less to manufacture shorter nozzles. Now a days, many 3D Printer manufacturers are opting for shorter nozzles for their machines.

(5) Nozzle Outside Shape –  In general, we have two types of nozzle shapes in the market – (a) Pointed Nozzles (b) Flat Head Nozzles. The latest Ultimaker 3D Printer comes with pointed nozzle. The major advantage of pointed nozzle is reduction of unwanted heat transfer to already deposited material. One important criteria for quality 3D Prints is to ensure the material cools down rapidly once deposited. But with flat-head nozzle, we again heat the material unwanted during the deposition of new layer. It becomes very clear when you try to print pyramids / cones / objects with pointed ends.

But the pointed nozzles require greater positioning accuracy and any wrong positioning may scratch the glass plate or deposited material easily. So, for more sturdiness we should opt for flat head nozzle and for better quality we should opt for pointed nozzle.

(6) Nozzle Inside Shape – There is no major limitation on the nozzle inside shape except for not letting thin conduits.

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What is Fused Deposition Modeling?

Fused Deposition Modeling (FDM), or Fused Filament Fabrication (FFF), is an additive manufacturing process that belongs to the material extrusion family. In FDM, an object is built by selectively depositing melted material in a pre-determined path layer-by-layer. The materials used are thermoplastic polymers and come in a filament form. Fused Deposition Modelling (FDM) was invented by Steven Scott Crump in 1988 who also Co-founded Stratasys.

I. A spool of thermoplastic filament is first loaded into the printer. Once the nozzle has reached the desired temperature, the filament is fed to the extrusion head and in the nozzle where it melts. 

II. The extrusion head is attached to a 3-axis system that allows it to move in the X, Y and Z directions. The melted material is extruded in thin strands and is deposited layer-by-layer in predetermined locations, where it cools and solidifies. Sometimes the cooling of the material is accelerated through the use of cooling fans attached on the extrusion head. 

III. To fill an area, multiple passes are required (similar to coloring a rectangle with a marker). When a layer is finished, the build platform moves down (or in other machine setups, the extrusion head moves up) and a new layer is deposited. This process is repeated until the part is complete.

Support Structure

Support structure is essential for creating geometries with overhangs in FDM because melted thermoplastic cannot be deposited on thin air. Surfaces printed on support will generally be of lower surface quality than the rest of the part. For this reason, it is recommended that the part is designed in such a way to minimize the need for support. 

Support is usually printed in the same material as the part. Support materials that dissolve in liquid also exist, but they are used mainly in high-end desktop or industrial FDM 3D printers. Printing on dissolvable supports improves significantly the surface quality of the part, but increases the overall cost of a print. 

FDM parts are usually not printed solid to reduce the print time and save material. Instead, the outer perimeter is traced using several passes, called the shell, and the interior is filled with an internal, low-density structure, called the infill. Infill and shell thickness affect greatly the strength of a part. For desktop FDM printers, the default setting is 25% infill density and 1 mm shell thickness, which is a good compromise between strength and speed for quick prints.

Design and Slicing

Just like any other form of 3D Printing, the CAD Model is developed using any 3D Design softwares like Solidworks, CATIA, NX, Fusion 360  etc. and the model is exported in STL file format. The STL file is then sliced to generate the GCode using the Slicing Softwares. Either the proprietary slicing software that comes with the printer manufacturer or the open sourced slicing softwares like Ultimaker Cura can be used. Cura has gained a lot of popularity in the community due to more features being added in every release and which is also free to use.

The sliced file contains the instructions for X, Y and Z movement of the printer head and the printer bed (Y), printing speed, temperature control. 

Parameters: Although there are several parameters that need to be set and fine-tuned for best results we will discuss the most important ones below.

a) Print Temperature: This is the vital parameter that controls the melting and deposition of the plastic filament accurately. This depends on the material of the filament being used. Improper print temperature can lead to defects like under extrusion or stringing of the nozzle. Every material has an optimal print temperature range for best strength and dimensional accuracy. For example, PLA prints best at 210 degrees. Beyond 220 degrees causes nozzle oozing and stringing and printing below 200 degrees C will not cause the layers to stick properly and part loses its strength. This trend is observed for other materials also.

b) Layer Height or Layer Resolution: This is the height of each layer used to build the 3D object. FDM printers are capable of printing layer heights of 0.1mm to 0.3 mm. A smaller layer height increases the layers required to build the object hence would consume a lot of time. A higher layer height can reduce print time but layer adhesion gets compromised hence the part strength also gets reduced.

c) Shells/Perimeters: These are the number of outer walls for the object. 2 to 8 perimeters can be used to strengthen the structure

d) Infill Percentage: Infill is the material that is added inside the body of the object being created. It is not always economical to fill the entire object with the plastic if the object only needs outer appearance and hence infill of 10 to 30% can be used. But this leaves gaps in the internal structure of the object and reduces strength. If strength is required 100% infill is recommended.

e) Infill Pattern: Grid or Hexagonal or Triangular patterns can be used for the infill.

Design Constraints

Minimum Wall thickness: 1.2 mm

Minimum details size: 2 mm (for text/ hole diameters etc)

Layer thickness: 0.1 mm – 0.3 mm

Max dimensions: 650 x 600 x 600 mm. Large parts can be created with assembling individual parts by interlocking designs or gluing together. 

Standard Accuracy: ± 0.3% (with lower limit on ± 0.3 mm).

Surface finish: visible layers with texture.

Strength

Strength has to be looked from 4 aspects

1)     Material aspect: Below are the tensile strength values of commonly used filament materials. HDT (Heat Deflection temperature is the temperature at which the material tends to lose its strength and rigidity. Shear strength can be considered as 50% of the tensile strength and flexural strength can be considered as 90% of the tensile strength.

MaterialTensile Strength in MPa in XY directionHeat Deflection Temperature (degrees centigrade)
Polycarbonate72120
PLA6550
PETG5380
Nylon(PA)4880
ABS4095

1)   Printing Temperature aspect. Improper printing temperature can bring down the specified strength by 50 %. 

2)   Hence this should be taken care while printing. Geometry and Orientation aspect: Z orientation always gives about half the tensile strength of the same part printed in XY direction irrespective of the layer height used. 

3)   Layer Height aspect: 0.1 to 0.2 mm layer height gives the maximum strength and increasing the layer height further reduces the strength by 30%.

If all 4 parameters are considered and taken care of properly, we can achieve the strength as stated in the table in point 1.

Materials

Each material suits a specific application. Applications include Visual Prototypes, Fit validations, Low-Volume Parts, Scale Models of Buildings and Automobiles, Functional Prototypes, Fixtures and holding tools, Sand-casting patterns with less details etc.

MaterialApplications
High strength and rigid parts. But generally toxic from environment perspective
PolycarbonateGeneral Purpose applications such as visual prototyping and design testing. PLA is Biodegradable making it eco-friendly. But material is brittle to failure. Can decompose or loose strength under sunlight. Should be kept away from moisture and water.
PLASubstitute for PLA where the part is subjected to moisture and water.
PETGSubstitute for PLA where a little bit of flexibility is needed such as snap fits
Nylon(PA)Substitute for PLA where the part is subjected to more than 50 degrees centigrade temperature and less than 100 degrees centigrade. Toxic if ABS fumes are inhaled hence need to be handled with care, hazardous in contact with fire.
ABSRubber like material that can be used for making soft toys.

There are a lot more materials available in the market and the complete material properties can be viewed here at https://www.simplify3d.com/support/materials-guide/properties-table

Advantages Of Fused Deposition Modeling

FDM iscost effective and a wide range of printable thermoplastic materials are available. Large prints can be done up to 750 mm x 750 mm x 750 mm

Limitations Of Fused Deposition Modeling

Dimensional accuracy is not so good (+/- 0.3 mm tolerance). Surface Finish is not so good in FDM and would generally require post processing like sanding, filing and acetone smoothing. Even after post-processing the surfaces typically have roughness value (Ra) of 25 to 125 micrometers. 

Hope you find this article interesting and gave you a know-how on why to choose FDM technology. At THINKFAB, we offer wide range of FDM 3D Printer at a high competitive price. Click here to request for quote.