Thermwood Corporation has developed a solution for large scale 3D printing following its acquisition of a patent for Vertical Layer Print (VLP) technology. By utilizing a Vertical plane instead of a horizontal one, Vertical Layer Printing makes it possible to produce items that are taller compared to prints made using the usual horizontal layer print.
Through Thermwood’s larger L-Sam systems, parts measuring over 20ft have been produced already. The LSAM (Large Scale Additive Systems) at Thermwood are made of high walls, a fixed table and moving gantries. Vertically printed parts are printed on a moving vertical table that is held up by stainless steel belts that glide on the main table.
In the past year, Thermwood came up with a cheaper LSAM system called MT that has a fastened gantry and a moving table. To do vertical printing on this system, a novel approach is employed. Parts are printed on a supporting framework that is attached to the back and slides on the moving table. As the parts are printed the mobile table places them onto the support structure. The LSAM – MT is capable pf printing parts of up to 5ft (Z Axis) by 10ft (X Axis) by 10ft (Y Axis).
Thermwood has used this method and produced parts using both high and low temperature thermoplastic material. They printed a part using carbon fibre strengthened ABS which works well for parts that work at or just above room temperature i.e. industrial tooling, foundry patterns, fixture, and other structural parts.
Another high-temperature part was also printed using Techmer blended 25% carbon fibre reinforced PSU/PESU. This printed part weighed 540kg which is the limit for a moving table system and it took 16 hours and 40 minutes to be printed.
PSU, PESU, PEI and others processed at high temperatures are used for making parts that are used in moulds and tools used in places with high temperatures i.e. autoclaves that use pressure and vacuum. Thermwood has succeeded in printing large parts that maintain vacuum as per aviation standard without using a secondary coating.
The MT and Thermwood’s LSAM is able to do both printing and trimming on the same machine. First it prints the parts and once cooled down, they are molded into their final size and shape. LSAM machines can print parts weighing up to 50,000 pounds. VLP equipped machines measuring 40ft long have already been assembled and delivered.