3D printing in metals

[Roger B]

Thank you for the suggestions. I have worked with some 3D cad in the past so I am aware of extrusion, constraints, components, assemblies etc. I may start off with Autodesk’s Tutorials.

I did have a quick play and put together a rather boxy crankcase with a bore for the camshaft and a couple of holes for the cylinders however I will go through the proper learning process.

[f2cf1g]

I have the Power Guide too and find it useful occasionally.  However, I got started in the very beginning with the Paul McWorter's "all new" Fusion 360 course on YouTube.  I expect he was new to Fusion himself so his demos are slow enough to follow reasonably well whereas the more experienced trainers often work much too fast to follow. Very basic but it's somewhere to start.  The bits about the Creality printer can be skipped but the rest gets across some useful information.  Autodesk have also recently released a new beginners course.

Concerning the accuracy of prints, my experience so far, with AlSi material printed by PCBWay, is similar to Vixen's, that the internal dimensions shrink and the external expand, i.e. the actual object grows a bit all round, typically 0.15-0.3mm.  In theory this might be enough to serve as a machining allowance but I always add more to be sure.  Precision is nowhere near that achievable by machining methods but probably better and more consistent than typical for hobbyist sand cast parts.  For my application, 2-stroke model aircraft engines, printing beats sand casting hands down because of the ease with which internal features such as transfer passages can be incorporated without complex coring or machining operations.

[Kim]

In addition to the other Fusion videos that have been suggested, I found Kevin's videos, from Product Design Onlilne, to be pretty helpful.  They are fairly new, having been redone in 2024, so they are showing a fairly recent version, which is helpful.  He does a "learn fusion in 30 days" approach where you do the tutorials in each video, one per day.  I did several of the first ones in a day, but then started to do them at a slower pace after I got the basics down.  Still, lots of useful concepts in each video.

https://www.youtube.com/playlist?list=PLrZ2zKOtC_-C4rWfapgngoe9o2-ng8ZBr

I also liked Lars's videos, but they are much older, and it can be challenging to translate to the new UI for someone unfamiliar with Fusion, which is likely anybody watching these videos! (It was for me, at least.  )

Kim

[GordonL]

I just tried to get a quote from Craft cloud for some pieces to get an idea on price etc. I submitted two drawings in STL format and filtered to steel and alloy. Both drawings came back as not available. Does anyone who has used this have any idea what is wrong?

[Jasonb]

I tend to use .STP Step files.

Make sure you don't have anything on the model that is too thin for the minimum detail and also check the size it comes in at, with Alibre I have to scale it to 1000% otherwise the items are 1/10th the size I want.

[GordonL]

OK Scale was the problem. a 2" square piece was 50+". It apparently was using metric instead of inches. 2" = 50.8mm. Price when rescaled was higher than I would be willing to pay. Thanks.

[maury]

Wow, this is good news and great stuff for those wanting to go the extra mile.
I think it opens the door to someone who wants to scale model a Dusenberg strait eight!

maury

[Jasonb]

Also Ideal for that compressor you are making, it would do a nice thin frame and cylinder fins.

I got a PM yesterday on another site from someone asking about the cart I made for my 1/3rd scale Galoway. Another good candidate for metal printing of the axles and bolster rather than a lot of time fabricating or doing patterns & castings.

[AlexS]

Tolerance so far for raw 3d print AiSi10Mg of 44 piston measured two point with micrometer around 44.05-44.15. Other sizes with caliper also 0.10-0.20 in the plus.

Picture second batch with the applied machining mainly for the connecting rod before annealing. M300 material when not hardened is good to machine and it contains low carbon so also weldable. 18% Nickel 9% Cobalt 5% Molybdenum. Hard and very strong when annealed.

Minimum wall thickness mostly around 1 mm and also for minimum holes.

2017 there was a stand on a technical fair showing a very huge printed engine block. Next to it an Ducati with some 3D printed parts, rims if I look right (sorry photo quality was not that good).