Birds-eye view of two Thermwood LSAM (Large Scale Additive Manufacturing) machines currently in production here at our factory. Get up close and personal with a 10'x20' as well as a massive 10'x40' LSAM Large Format 3D printer. 

About The Thermwood LSAM

Thermwood offers a line of dual gantry additive manufacturing machines which both print and trim parts on the same machine. These are large industrial additive manufacturing machines that can be up to 100 feet long.  

The Thermwood LSAM is used to produce large to very large sized components from reinforced thermoplastic composite materials. 

Although suitable for producing a wide variety of components, Thermwood is focusing on producing industrial tooling, masters, patterns, molds and production fixtures for a variety of industries including aerospace, automotive, foundry and boating.    

The video below shows the process of creating a 3D printed boat hull pattern (from which fiberglass boat hull molds are made), on a Thermwood LSAM. 

Click for More Information on the process

This achievement was the result of a collaborative effort between Thermwood Corporation,Techmer PM and Marine Concepts.

The tool was printed slightly oversized and then trimmed to final net size and shape using a Thermwood’s large scale additive manufacturing (LSAM®) system.

It was made from Techmer’s Electrafil© ABS LT1 3DP, which has proven ideal for marine tooling applications when processed using LSAM print technology. The entire print, assembly and trim process required less than ten working days to complete. After the printed and trimmed tool was coated and finished, a fiberglass mold was produced using the printed pattern. This effort clearly demonstrates the feasibility, practicality, economics and advantages of using additive manufacturing in the production of boat tooling. 

The final tool was printed in six sections, four major center sections with walls approximately an inch and a half thick and a solid printed transom and bow, which were pinned and bonded together using Lord plural component urethane adhesive before being machined as a single piece on the Thermwood system.

A cooperative effort between Thermwood Corporation, Applied Composite Engineering (ACE), Techmer PM and Purdue University’s Composites Manufacturing and Simulation Center has produced a composite helicopter part using a 3D Printed Polysulfone (PSU) mold.

PSU mold printed and machined on a Thermwood 10'x20' LSAM®

Final Part from mold (oil drip pan for a Chinook Helicopter)

The Details

The mold was printed from Techmer supplied carbon fiber reinforced material and trimmed on Thermwood’s Large Scale Additive Manufacturing (LSAM®) machine. ACE produced a production part from the tool in an autoclave using normal production processes.

Despite the fact that Polysulfone appears to be an ideal material for this application, the participants believe this is the first time PSU has been 3D printed, since it processes at temperatures and requires torque levels above those needed for normal polymer extrusion.  The extruder and print head on Thermwood's LSAM machine has been specially designed for ultra-high temperature, high-torque operation.

3D Printing Mold on Thermwood 10'x20' LSAM®

The part, an oil drip pan for a Chinook Helicopter, was molded in an autoclave at 275^oF and 90 PSI. The printed mold held vacuum without the need for special coatings other than normal mold prep and release. With a Tg (glass transition temperature) of 372^oF the participants believe that this particular PSU formulation may be able to process parts at up to 350^oF which is adequate for about 95% of composite parts processed today. Additional tests will be performed to determine the suitability and durability of this material at this temperature. They also plan to evaluate Polyethersulfone (PES) which processes and operates at even higher temperatures.

The PSU mold and resulting part were displayed at the recent AM2017 Additive Manufacturing Conference in Knoxville.

Comparison vs Traditional Methods

Another interesting aspect of this collaborative effort is that a mold for the same part was built by ACE using traditional methods and the cost and build time was compared to making the same tool using additive manufacturing. The results were stunning.

The Results

Additive manufacturing material cost was 34% less and it required 69% fewer labor hours. Build time for the additive tool was 3 days versus 8 days for the conventional tool. If the part was larger, a support structure would be needed for the conventional tool which would add two days and more labor hours to the conventional process. A larger additive tool would not require a support structure.

The goal of this collaborative effort is to develop materials and processes to efficiently and reliably 3D print production composite tooling, capable of operating at elevated temperatures in an autoclave. These first successful results may indicate that they are very near reaching that goal.

Collaborative partners on this project

Applied Composites Engineering – Composites is their business focusing on aerospace. With nearly thirty years in the industry they have shown core competency rarely found in a company their size. This combination of capability and experience provides their customers with the benefits of a larger company supporting more sophisticated projects and larger production along with the speed and flexibility of a smaller enterprise.  

Purdue’s Composites Manufacturing and Simulation Center – Their primary focus among others is to develop a comprehensive set of simulation tools that connect composites from their birth in manufacturing to predicting their useful life. They predict and measure the anisotropic deformation that occurs in printed elements, including a description of anisotropic element shape change during deposition in order to anticipate performance of the printed element.

Thermwood Corporation – Pioneer in CNC development, first company to build and sell a CNC router has moved aggressively into developing and building large scale additive manufacturing systems and industry leading software. Its LSAM (L-Sam) system prints and trims large to very large molds and tools that are solid, virtually void free and able to sustain vacuum without secondary coatings.

Techmer PM - A leading manufacturer of high-performance custom compounds used in the plastics industry, they seek to deliver value-added, breakthrough solutions to the OEM and processing communities worldwide. Working extensively with the additive manufacturing community they have developed materials ideally suited to the additive manufacturing process and have wide-ranging experience with additive manufacturing technology.

A 3D printed boat hull pattern, from which fiberglass boat hull molds are made, has been completed using a near net shape additive manufacturing process and then successfully used to produce a production capable fiberglass mold in a proof of concept joint evaluation program. The completed pattern was recently displayed at the AM2017 Additive Manufacturing Conference in Knoxville, Tennessee. 

Video 

Finished boat hull pattern - shown with Thermwood LSAM® 10'x20' machine

A Collaborative Effort

This achievement was the result of a collaborative effort between Thermwood Corporation,Techmer PM and Marine Concepts. The tool was printed slightly oversized and then trimmed to final net size and shape using a Thermwood’s large scale additive manufacturing (LSAM®) system.

It was made from Techmer’s Electrafil© ABS LT1 3DP, which has proven ideal for marine tooling applications when processed using LSAM print technology. The entire print, assembly and trim process required less than ten working days to complete. After the printed and trimmed tool was coated and finished, a fiberglass mold was produced using the printed pattern. This effort clearly demonstrates the feasibility, practicality, economics and advantages of using additive manufacturing in the production of boat tooling. 

The Details

Thermwood LSAM® 10'x20' machine printing two of the six sections

The final tool was printed in six sections, four major center sections with walls approximately an inch and a half thick and a solid printed transom and bow, which were pinned and bonded together using Lord plural component urethane adhesive before being machined as a single piece on the Thermwood system.

Bonding the boat hull pattern pieces together

Bringing the two sections together

Boat hull pattern after bonding together and before machining

Thermwood LSAM® 10'x20' machining boat hull pattern

The final trimmed pattern weighs approximately three thousand pounds. It required approximately thirty hours to print and fifty hours to machine.

Final trimmed pattern before coating

Thermwood’s demonstration machine, used for this program, has a 10 foot by 20 foot worktable and features both print and trim capability on the same machine. The print head used for this project can print at rates approaching 200 pounds an hour when running this particular Techmer material. Thermwood also offers larger machines and higher throughput print heads as part of its LSAM product line. 

Pulling the Mold

Building frame on boat hull pattern to pull mold

Finished frame on boat hull pattern after casting the fiberglass mold

Removing fiberglass mold from boat hull pattern

Finished boat hull mold in red

Additive Manufacturing Could Change Marine Tooling Process

Additive manufacturing offers the promise of even more advances in marine tooling such as printing the hull and deck pattern as a single piece, allowing a production mold to be taken from the hull and then flipping the pattern over and taking a deck mold from the other side of the same pattern. All of these possibilities result in dramatically lower tooling cost and substantially faster build time. 

For large boats and yachts, Thermwood is evaluating the feasibility of printing molds directly, rather than printing a pattern from which the mold is taken. Because of their large size, these tools will need to be printed and machined in sections, even with very large LSAM® printers. It may also be possible to print integrated cooling channels for air or liquid into these large tools as part of the print process. 

With this initial success and some radical new ideas that appear to be possible with current materials and technology, it is becoming apparent that additive manufacturing may very well represent a disruptive force for the marine tooling industry.

Thermwood has taken a major step toward its goal of 3D printing autoclave capable tooling from high temperature carbon fiber filled thermoplastic materials.

As an added benefit, Thermwood believes it will soon produce molds and tooling that function properly under vacuum in a heated, pressurized autoclave without the use of any type of coating to seal the printed tools. 

50% Carbon Fiber filled PPS Panels Tested by Fleet Readiness Center

50% Carbon Fiber Filled PPS Panel Printed and Machined on LSAM

Working toward this goal, Thermwood engineers have printed 50% Carbon Fiber filled PPS panels on its LSAM additive manufacturing machine that held vacuum to an industry acceptable level in independent testing. The test was conducted by the Fleet Readiness Center, FRC-East, located at MCAS Cherry Point, NC under a previously announced Cooperative Research and Development Agreement (CRADA) partnership, and the results met FRC-East acceptance criterion that the bag must not lose more than 2 in Hg over 5 minutes.  

View of LSAM PPS Sample with Vacuum Bag

Previously, other unaffiliated companies have tested actual tools printed by Thermwood from 20% Carbon Fiber filled ABS and have also found that those tools held vacuum to an acceptable level without the use of any sealer or coating; however, the ABS material is not suitable for high temperature applications. 

LSAM ABS Demonstration Part showing as printed (rough cut and finished surfaces) 

Vacuum Bagging Test on LSAM ABS Demonstration Part at Fleet Readiness 

Despite that, several parts have been made from those tools under vacuum at room temperature and at slightly elevated temperatures. Thermwood has also already printed a 50% Carbon Fiber filled three dimensional PPS mold which has not yet been tested. Thermwood’s goal is to produce molds that will be used in a production autoclave, molding finished parts suitable for actual end use. 

Thermwood's Additive Printing Process 

Thermwood’s additive printing process differs fundamentally from conventional Fused Deposition Modeling (FDM) printing. Most FDM processes print parts by melting and extruding a relatively small bead of thermoplastic material onto a heated build platin that is contained within a heated chamber. The heated chamber keeps the extruded material from cooling too much before the next layer is added.

Thermwood machines print a large bead at such a high rate that a heated environment is not needed. It is basically an exercise in controlled cooling. Print speed is adjusted so that each layer cools to the proper temperature just as the next layer starts to print resulting in a continuous printing process that produces high quality parts. Thermwood believes this fundamentally different approach produces superior parts. 

Thermwood's Patent Pending Compression Roller 

One other feature that Thermwood engineers believe helps produce solid, void free parts, is a patent pending compression roller that follows directly behind the print nozzle, flattening the bead while fusing it tightly to the previous layer. 

More About LSAM

Thermwood’s large scale dual gantry LSAM machines both print and trim parts on the same machine. They are programmed with Thermwood’s LSAM Print ^3D slicing software, which is rapidly becoming the most capable additive manufacturing software in the industry.

The LSAM and its software operate within Mastercam and are specifically designed for near-net-shape, rather than net-shape printing.

It works with most major CAD file formats including virtually all solid, surface and mesh formats. Thermwood maintains a continuing software development effort to continuously improve, enhance and expand its features and capabilities.

New Print Head Design for LSAM

Thermwood Corporation has unveiled a new design for the print head on its large scale additive manufacturing machines which it calls LSAM, (pronounced L-Sam). This new “Universal” design print head can be equipped with any of three interchangeable “Melt Cores”.

The print head is large by industry standards, being over 10 feet long and weighing one and a half tons, but despite the size and weight it moves at speeds up to five feet per second. The print head is designed so that the “Melt Core”, which consists of a feed housing, extruder and polymer melt pump, can be changed should higher or lower print rates be required.

Universal Print Head Installed on LSAM Development Machine

Thermwood has installed a universal print head on its current 10’ x 10’ LSAM development machine with a 40mm Melt Core and has successfully printed composite tooling masters from 20% Carbon Fiber filled ABS, and has printed actual autoclave tooling from both 50% Carbon fiber filled PPS and 20% Carbon Fiber filled Ultem using this print head. 

LSAM is DIfferent Than Other Thermoplastic 3D Printers

The print head is a critical element in Thermwood’s additive manufacturing process which functions differently than other FDM thermoplastic 3D printers. Most thermoplastic additive manufacturing systems print with a relatively small print bead onto a heated table in a heated environment. The heated environment is needed to keep newly printed layers from getting too cool to properly fuse with subsequent layers.

In Thermwood’s approach, the only heat source is the print head itself. A heated environment isn’t required. The process prints a large bead at such high output rates that the printed layer must be cooled rather than heated to achieve the proper layer to layer fusing temperature. The entire process is essentially an exercise in controlled cooling and produces large size, high quality, virtually void free printed structures.

Each layer is printed at a rate that allows it to cool to the ideal temperature before the next layer is applied. If the layer becomes too hot, print speed is reduced to allow more cooling time. If it becomes too cool, print speed is increased to reduce cooling time. 

Real-Time Thermographic Image Display

A built-in thermographic imaging system displays a real time thermal image on the CNC control screen which aides the operator in achieving and maintaining the ideal print temperature during the print process.

Temperature Control Module Integrated into LSAM

The LSAM Universal Print Head can process material at temperatures up to 450^oC. It uses an electronic temperature control module integrated within the print gantry CNC control, allowing full integration of temperature and pressure control with exclusive features of Thermwood’s print gantry CNC control, better supporting processes unique to 3D printing.

Three Melt Core Choices for LSAM

Thermwood offers three melt cores for its print head, each with a different maximum print rate. The maximum print rate determines the longest bead that can be printed during the available cooling time between layers.  This cooling time varies depending on material, amount of fan cooling and geometric shape of the layer, but the faster the print rate the more material that can be laid down within the cooling time between layers, so faster print heads allow larger parts to be printed, but don’t really print parts faster.

Fastest Printing With LSAM

Even the standard 40mm LSAM melt core is generally so fast that it must be slowed on most parts to keep from printing a layer so fast that it doesn’t have sufficient time to cool properly between layers. In this case, often multiple parts can be printed in the same time it takes to print just one.

The LSAM machine is equipped with a standard 40mm Melt Core which includes a patented 40mm high speed extrusion screw coupled to a corresponding melt pump and deposition head. This standard configuration processes over 200 pounds of material an hour, depending on the specific material and is suitable for parts that have a print layer lap length of up to 200 feet while printing a standard bead that is .200 inch thick and .830 inch wide. This configuration has proven more than adequate for virtually all large parts today.

If even longer layer bead lengths are required, higher output Melt Cores are available. A 60mm Melt Core can process 50% more and a 70mm Melt Core has operated at rates of over 500 pounds per hour, which Thermwood expects to increase.

The fastest speed at which a part can be printed is determined by the cooling time required to reach the proper bonding temperature between layers and not by the output of the print head. Larger print head outputs simply allow larger parts to be printed within the cooling time between layers.

High output melt cores do, however, have a minimum operating speed so may not be suitable for smaller parts. If both small and really large parts are required on the same machine, the melt core can be changed from one size to another in less than a shift. 

New 10'x20' Demonstration LSAM Under Construction

This print head will be installed on a new 10’ x 20’ demonstration machine currently under construction at Thermwood. Production machines come standard with the 40mm Melt Core.

Thermwood’s LSAM machines both print and trim on the same machine using separate gantries. The new approach to print head design adds even more flexibility.

LSAM Produces Solid, Void-free Parts

Using this technology, Thermwood has been able to produce large tools that are solid and void free enough to maintain vacuum without sealing or surface coating. This simplifies production of the tool, allowing accurate machining of the surface without having to deal with distortions that might be caused by variations in the thickness of a coating. 

Print and Trim on the Same Machine

Thermwood offers a line of dual gantry additive manufacturing machines which both print and trim parts on the same machine. These machines can be up to 100 feet long with print head output rates from 150 to 500 pounds per hour.  

The Thermwood LSAM is used to produce large to very large sized components from reinforced thermoplastic composite materials.

Although suitable for producing a wide variety of components, Thermwood is focusing on producing industrial tooling, masters, patterns, molds and production fixtures for a variety of industries including aerospace, automotive, foundry and boating.   

Thermwood Corporation of Dale, Indiana has signed a formal Cooperative Research and Development Agreement with Fleet Readiness Center East located at Marine Corps Air Station Cherry Point, N.C., and part of the Naval Air Systems Command, to conduct a two-year, joint technology development effort centered on Thermwood’s emerging Large Scale Additive Manufacturing (LSAM) technology.

Thermwood’s LSAM machines are large-sized industrial additive manufacturing or three-dimensional printing machines that are available in sizes up to 100 feet long. These systems use a “near-net-shape” approach for making parts in which parts are first 3D printed at high speed to a size slightly larger than needed and then trimmed to final net size and shape. Thermwood’s LSAM machine consolidates printing and machining on the same machine using dual gantries. Dual controls allow print and trim operations to be performed simultaneously, each on different ends of the table.

“We are excited to work with the FRC East and are confident that, working together, we can achieve significant advances and results,” said Thermwood Founder, CEO and Chairman Ken Susnjara. “I am confident that this program will benefit us both while further advancing the state of the art.”

Thermwood has been in a continuous research and development program developing additive manufacturing equipment and technology, and in September announced a line of large scale additive manufacturing systems called LSAM. The dual-gantry, high-wall machines are available in sizes from 10-foot-by-10-foot to 10-foot to more than 100-foot with print capability from 150 to 500 pounds per hour.

 About Thermwood Corporation:

Thermwood Corporation, located in Southern Indiana and established in 1969, offers both three & five axis CNC machining centers ideally suited for the production, fabrication & trimming of wood, plastics, non-ferrous metals, composites and other advanced materials.  Thermwood also offers a Large Scale Additive Manufacturing (LSAM) system for 3D printing reinforced thermoplastic composite materials for producing industrial tooling, molds, patterns, masters, plugs and fixtures for various industries.  Thermwood is deeply involved in CNC and Additive Manufacturing technologies and development, incorporating a high level of smart control technology in its products. 

About Fleet Readiness Center East:

For more than 60 years, the Fleet Readiness Center (FRC) East aboard MCAS Cherry Point, N.C., has played an important part in national defense.  Our workforce has earned a reputation of excellence in providing world-class maintenance, engineering and logistics support for Navy and Marine Corps aviation, as well as other armed services, federal agencies and foreign governments. Our skilled workforce uses state-of-the-art technology to ensure that FRC East is without equal in providing quality, cost-effective support. 

 

About the Thermwood LSAM