Helicopter DLR wind tunnel model

Posted by Petra Rapp on August 13, 2020 .

 wind tunnel model

		dimension		1.84m length
		weight		7.5kg
		material		Multec PLA-HT
		print time		120 h

At the request of the German Aerospace Center, a 3D-printed helicopter wind tunnel model with a length of approx. 1.84 meters . The multi-part model is printed and screwed together in several parts.

Due to the manufacturing process in 3D printing, interior areas can be printed mostly hollow , only areas that are particularly stressed are specifically reinforced and provided with greater wall thicknesses and filling levels.

Despite its size, the model only weighs 7.5 kg and withstands wind speeds of up to 270 km/h .

Multec PLA-HT is used as the material. The material is characterized by high strength and temperature resistance.

Perfect surfaces are required for wind tunnel models to avoid incorrect measured values ​​due to turbulence. The printed model was therefore subsequently sanded down and varnished . Due to the good reworkability (grinding, drilling, etc..), PLA-HT is ideal for painted components.

Compared to the conventional production of wind tunnel models from fiber composite materials, 3D printing is faster and cheaper .

In conventional manufacturing, molds must first be milled, which are then used to manufacture components from glass/carbon fiber composites. Mold construction usually requires multi-part molds and is time-consuming and costly. The components are often manufactured by hand and this is also associated with a great deal of effort.

In 3D printing, even complex geometries can be reproduced in a single work process. Mold making is completely eliminated - depending on the size of the component, the printed component is ready for use within a few working days. Due to the additive structure of the model, material is only applied where it is needed - there is virtually no waste compared to machining.

Overall, 3D printing at Multec saved several thousand euros in mold construction costs compared to production using lamination technology, and the delivery time from the order to the finished component was reduced enormously. The ecological footprint of 3D printing with this Multec PLA-HT material is also excellent, as it is produced from renewable raw materials and is both recyclable and biodegradable.

Mercedes CLK W208 scale 1:10

Posted by Petra Rapp on August 13, 2020 .

Model car M1:10 Mercedes CLK originally painted by the MB drift team

		dimension		45cm length
		weight		670g
		material		Multec PLA-HT
		print time		52h

For the MB drift team https://www.facebook.com/MBDRIFTTEAM79/ we printed a model car based on an original scan of the Mercedes CLK W208, which was then painted true to the original.

This 3D print is a good example of optimizing the surface without considering the printing time. The orientation was chosen so that all visible surfaces look good , although a lot of support structures are necessary : ​​The component itself weighs only 670g, the support structure 830g.

Multec PLA-HT material , since the relatively thin-walled model must have good strength and temperature resistance (solar radiation). Good sandability is helpful for this, since the model should then be filled after the printing process.

Multec PLA-HT has 150% higher impact strength than ABS and comparable temperature resistance. And these benefits with virtually no warping/shrinking and no harmful substances . Furthermore, the material convinces with its recipe made from renewable raw materials without petroleum content and full biodegradability (also no dyes in the natural version).

The printing process of the model car is shown in the timelapse:

The MB drift team made a great video out of it, thank you for the great cooperation!

https://www.facebook.com/MBDRIFTEAM79/posts/2745569705546562