Lotus Elan and Lotus Elan Plus 2 Forums

Very amazing

https://m.youtube.com/watch?feature=emb ... Up3oCGZOzk

Indeed.

I had not realised how widespread 'additive manufacturing' was until my son got involved in the Aerospace industry. For anything but prototypes or very low production numbers, the example shown would have been better sand-cast, but there are some manufacturing processes (either because of the material used or the intricate design) that really can only be achieved using additive manufacturing. SpaceX make their Super Draco boosters out of Inconel, which apparently is a swine to work with. Remarkably they are 3D printed.

https://additivemanufacturingtoday.com/spacex-uses-dmls-to-3d-print-inconel-superdraco-engine-chamber

There are videos on Youtube of hobbyists using plastic 3D printed parts as the patterns for investment casting - which I suppose is a halfway house to additive manufacturing. If Coolex hadn't started to make the 'Cliveyboy' thermostat housing, I was going to have a go myself at printing a plastic 3D pattern and casting the housing in my garden.

https://www.youtube.com/watch?v=HVgPM1ojyLw

The Lost Wax process has been around for a while
Alan

Casting has limitations related to filling the mould. 3D printing frees us from these constraints and allows different designs which can be more weight efficient putting material only where it is needed.

I am interested in finding out more about the metallic structure of the results as this is key to its strength (cf. Cast vs forged Cranks)

alan.barker wrote:The Lost Wax process has been around for a while
Alan

Very true. Since 3700BC according to Wikipedia.

Using a 3D printed pattern is technically 'lost PLA' not 'lost wax' and isn't additive manufacturing, but does allow a hobbyist to be able to produce a cast item from a CAD file at home (assuming you have a 3D printer, a small furnace, and an understanding wife).

mikealdren wrote:Casting has limitations related to filling the mould. 3D printing frees us from these constraints and allows different designs which can be more weight efficient putting material only where it is needed.

I am interested in finding out more about the metallic structure of the results as this is key to its strength (cf. Cast vs forged Cranks)

Mike, there is a lot about this on the web. I believe SpaceX have to sinter the engine produced by Laser Powder Bed Fusion (LPBF) to improve its mechanical properties after printing.

GE have Electron Beam Melting, which works the same way as LPBF, but only works with metallic powder, and only in a vacuum. It seems that the mechanical properties of this process benefit by not having any oxidation of the powder during the melting process.

The whole thing in the original post struck me as really impractical especially for a one-off, but the time and expense were probably justified as a 'showcase' instance.

For your interest here's some pictures of eight Bugatti Chiron cam covers that have been 3D printed (SLM) in AlSi10Mg, on show at the Formnext exhibition in Germany. The information said it took 4 days, 7 hours and 42 minutes to print.




This type of 3D metal printed part needs stress relieving in an oven or furnace before it is finish machined.

Paul

Andy8421 wrote:Using a 3D printed pattern is technically 'lost PLA' not 'lost wax' and isn't additive manufacturing (Snip)...

For Investment casting with 3D printed masters, it can still be 'lost wax'. There are many resins available for 3D printing, plus wax. For investment casting, you switch to a reel of wax, and 3D print the wax masters. Once you have the wax masters, the rest of the investment casting process is the same.

PLA may also work (?), but wax is still the preferred option with 3D printed masters.

Regards,
Tim Engel

Impressive. No doubt that 3d printers can do amazing things.

Surprise how good that 3D printed aluminum results! My buddy might get interested in this technology. Last time I helped him install the suspension from 4Wheelonline onto his truck, he mentioned he's taking in charge of his father's shop and he's thinking of adding more services.