Large Composite Stretch Form Tool Advances Additive Manufacturing Technology

Posted by Duane Marrett on Wed, Jun 15, 2022

Tags: Thermwood, tooling, LSAM, Thermwood LSAM, LSAM 1020, Spirit Aerosystems, Additive tooling

THE DETAILS: 

It was determined that carbon fiber filled polycarbonate would provide sufficient strength to withstand the significant forces used in the stretch form process, however unlike traditional lubrication methods, Techmer PM blended a new polycarbonate formulation that contained an internal lubricant in addition to the carbon fiber, eliminating the need for any additional lubrication.

THE PROCESS: 

The tool was printed on Thermwood’s LSAM 1020 dual gantry print and trim system. While this machine is equipped with Vertical Layer Printing and could have printed the tool in one piece, because it requires that you to wait for each printed layer to cool enough before adding the next layer, it would have required 58 hours of continuous print time to produce a one-piece tool. Instead they decided to print the part in four sections, two at a time for a total print time of 29 hour and 20 minutes, cutting the print time in half. Printing required 3,613 pounds of material.

The Four Parts Printed

The Four Parts Printed

The four parts then needed to be machined and assembled.

Layout of the assembly

Layout of the Assembly

All surfaces of the parts except for the front working surface were then machined in place.

Initial Machining

Initial machining.  The holes in the center of each side are for center-of-gravity brackets used for part handling during assembly.

The mating faces were then machined flat except for slightly raised bosses which insured proper gapping for the adhesive. Adhesive is only one part of a multi part approach used to permanently and securely attach the parts to each other. These are all highly accurate, precision surfaces.

Flat Face has raised bosses to provide proper adhesive gap.

Flat Face has raised bosses to provide proper adhesive gap

PUTTING IT ALL TOGETHER:

Draw bolt holes and slots were machined into the back of the tool which allow the parts to be bolted together in addition to the adhesive.

Machined area for draw bolts

Machined area for draw bolts

In addition to adhesive and draw bolts, alignment holes and countersink holes were machined into the center sections of the tool.

Alignment and countersink holes

The 6-inch long alignment pins for these holes are machined with adhesive channels providing not only alignment between parts but also another level of permanent attachment.

Heavy duty alignment pins offer another attachment layer

Heavy duty alignment pins offer another attachment layer

The next level of attachment uses brackets positioned inside the structure near the front surface, which are attached to each other using tensioned aircraft steel cables, securely holding the front surface of the four parts together.

Brackets with temporary straps which were replaced by tensioned steel cables

Brackets with temporary straps which were replaced by tensioned steel cables

The parts were then final assembled using another unique approach. Each part is relatively heavy and because of relatively short open time for the adhesive, there is a limited amount of time available during assembly to apply the adhesive and mate the parts securely together. The parts need to be pushed together while aligned, literally within a few thousandths of an inch and need to be mated absolutely even and square. This turned out to be fairly easy using the Vertical Layer Print table mechanism installed on the LSAM machine.

The parts were carefully hand fitted together. Then, one part was attached to the machine table and the other to the mechanism that moves the vertical table. The vertical table drive then moved the parts apart about 20 inches, adhesive was applied and the vertical table mechanism pushed the parts back together again, square and perfectly aligned.

Adhesive being applied to separated pieces.

Adhesive being applied to separated pieces

Draw bolts and cables were permanently attached and after the adhesive fully cured, the completed tool front surface was machined to final dimensions using the LSAM trim head. When Spirit AeroSystems measured the final working surface it was within +/- 0.005”, well within their requirements. Total of all machining including the final working surface was 118 hours and 58 minutes.

THE RESULTS:

Front surface measured to within +/- 0.005”

Front surface measured to within +/- 0.005"

Spirit AeroSystems then stretched 10 skin panels of 0.050” thick 2024 T3 aluminum to 5% elongation. The press controller showed that each jaw gripping the aluminum sheet had ~100 tons of load on it, so ~200 tons in total. Everything was kept under the same conditions as if running a production part and although the printed tool was considerably lighter in weight than their traditional tools, it appeared to perform in a similar manner.

Skin panel being stretched

Skin panel being stretched

THE BOTTOM LINE:

This is a first step. There are additional tests to be performed and more data to be collected, but it does appear that large 3D printed composite stretch form tools can be produced using currently available material and current equipment, saving considerable time and money and opening yet another application for this exciting new technology.

ABOUT SPIRIT AEROSYSTEMS:

Spirit AeroSystems is one of the world's largest manufacturers of aerostructures for commercial airplanes, defense platforms, and business/regional jets.  Also, Spirit serves the aftermarket for commercial and business regional jets.

ABOUT THERMWOOD:

Thermwood is a US based, multinational, diversified machinery manufacturer that has become the technology lead in large scale additive manufacturing of thermoplastic composite molds, tooling, patterns and parts with its line of LSAM (Large Scale Additive Manufacturing) systems that both 3D print and trim on the same machine.  

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Thermwood LSAM 2020 Year in Review

Posted by Duane Marrett on Wed, Dec 09, 2020

Tags: Thermwood, Announcements, Video, 3D printing, LSAM, Thermwood LSAM, LSAM MT, LSAM 1010, LSAM 1020, 2020, Review

LSAM_SeriesRV3_2020_mod.fw-1Thermwood LSAM 2020 - Year in Review

The last 12 months have seen an incredible level of disruption in all industries, fueled in large part by the coronavirus pandemic.  COVID-19 has impacted nearly every aspect of the global economy, from manufacturing to supply chains to travel.

The additive industry wasn’t spared, with event cancellations and disruptions to regular business becoming the norm.  Thermwood pivoted in 2020 to continue our focus on innovation and development with our LSAM (Large Scale Additive Systems) line, and have made many new discoveries and advancements in our additive manufacturing program.

Below, we highlight some of the notable LSAM moments from 2020 that leaves us hopeful for the future of large scale additive manufacturing in 2021 and beyond:

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March 5th - Thermwood Announces Another New LSAM Model

Thermwood Introduces the LSAM 1010

To address the need for a lower cost enclosed additive machine, Thermwood developed the LSAM 1010. This system uses the walls from the larger LSAM systems with the gantry, control and sub-systems from the LSAM MT. 

The LSAM 1010 features a fixed 10 foot by 10 foot table. A single moving gantry carries both the print and trim heads as on the MT and, like the MT, it can both print and trim (but not at the same time). The print and trim heads on all Thermwood LSAMs are the same, so all machines can process virtually any reinforced composite thermoplastic materials available today.

With the introduction of the LSAM 1010, it became clear that Thermwood is committed to responding to customer requests and providing its industry-leading LSAM additive manufacturing technology in a variety of configurations to better fit varying customer requirements.


March 17th - Thermwood LSAM 1020 Quickly 3D Prints a Multi-Piece Foundry Pattern

 

HubSpot Video

This was a great exercise to demonstrate the capabilities of an LSAM to quickly make a multi-piece foundry pattern out of ABS (20% carbon fiber fill). 

The pattern was printed on an LSAM 1020 in 6 hours and 40 minutes, and machined on a Thermwood 5 Axis Model 90 (because of other projects that were pending on the LSAM).

More info


June 25th - Thermwood Builds Massive Metalworking Machine to Increase LSAM Production

Thermwood Builds Massive Metalworking Machine to Increase LSAM Production

Thermwood designed, fabricated and put into operation the largest machine it has ever built. The metalworking machine, dubbed internally as the M400, weighs 51 Tons (103,000 pounds) and is mounted on a special isolated, double steel reinforced concrete pad. It has a 15 foot wide, 35 foot long floor level steel table that by itself weighs 21,000 pounds.

More info


August 27th - Thermwood LSAM MT VLP Prints a High Temperature Part

HubSpot Video

In August, Thermwood demonstrated it's VLP (Vertical Layer Printing) capabilities on an LSAM MT 1010.  The high-temperature part was printed out of Techmer PM blended 25% carbon fiber filled PSU/PESU. 

Total print time for the project was 16 hours and 40 minutes, and the final weight of the part was 1,190 lbs.  The final part dimensions were 108.6" (x) x 33" (Y) x 45" (Z).

More info


September 17th - Thermwood and General Atomics Partner on Additive Tool with $50,000 Cost Savings

HubSpot Video

In September, Thermwood partnered with General Atomics to produce a CNC trim tool.  The tool was printed from ABS (20% Carbon Fiber Filled) in 16 hours.  Total machining time was 32 hours.  The final part weighed 1,190 lbs, and represented a cost savings of around $50,000 when compared to traditional methods.

Total lead time for the part decreased from 6-8 weeks to less than 2 weeks by utilizing the powerful LSAM system.

More info


September 24th - Take a Tour of the Thermwood LSAM

HubSpot Video

Also in September, LSAM Product Manager, Scott Vaal, took us on an informative tour of the Thermwood LSAM.

In this tour, Scott explains all the different aspects of the Thermwood LSAM and provides insight into this unique solution for large scale additive manufacturing.  

More info


October 22nd - A New Approach to 3D Printing a Yacht Hull Mold

A New Approach to 3D Printing a Yacht Hull Mold

In October, Thermwood printed a several sections from a 51 foot long yacht hull mold to demonstrate how only a single mold may be needed for the manufacture of larger vessels, such as yachts. 

The printed sections of this test mold were made of carbon fiber reinforced ABS from Techmer PM. ABS was chosen because of its physical properties and relatively low cost compared to other reinforced thermoplastics

More info


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Take a Tour of the Thermwood LSAM

Posted by Duane Marrett on Thu, Sep 24, 2020

Tags: Thermwood, Announcements, Video, 3D printing, Additive, LSAM, LSAM 1020

Take a Tour of the Thermwood LSAM

LSAM Product Manager, Scott Vaal, takes you on an informative tour of the Thermwood LSAM (Large Scale Additive Manufacturing), a unique solution for large scale additive manufacturing.

LSAM is a complete system that can both print to near net shape and then machine the print to its net shape.  By far, the fastest way to 3D print large tools or parts.

HubSpot Video

Stay tuned for the next release in this exciting new series of videos from Thermwood!


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Watch a Thermwood LSAM 1020 3D Print a Multi-Piece Foundry Pattern

Posted by Duane Marrett on Tue, Mar 17, 2020

Tags: Thermwood, Announcements, Video, 3D printing, Additive, LSAM, Pattern, Foundry, LSAM 1020

Thermwood recently completed a 3D printed multi-piece foundry pattern.  The pattern was printed on an LSAM 1020, and machined on a Thermwood 5 Axis Model 90 (because of other projects that were pending on the LSAM).

The pattern was printed out of ABS (20% carbon fiber fill).  Print time for the project was 6 hours and 40 minutes, and the trim time was a little over 47 hours with multiple fixture setups.

Click below to watch a video of the process:

The final pattern after trimming

The final pattern after trimming

The completed and assembled pattern.
The completed and assembled pattern.

About Thermwood Corporation

Thermwood is a US based, multinational, diversified CNC machinery manufacturer that markets its products and services through offices in 11 countries. Thermwood is the oldest manufacturer of highly flexible 3 & 5 axis high-speed machining centers known as CNC routers.

Thermwood has also become the technology and market leader in large scale additive manufacturing systems for thermoplastic composite molds, tooling, patterns and parts with its line of LSAM (Large Scale Additive Manufacturing) machines that both 3D print and trim on the same machine. These are some of the largest and most capable additive manufacturing systems ever produced and are marketed to major companies in the aerospace, marine, automotive and foundry industries as well as military, government and defense contractors.


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