On FDM I think the main issue would be support on the inside of the “bulb” near the top where it starts to become near horizontal. I think that you’d need to add a column up the middle and possibly branch out with some custom support. That is FDM.
All of those tiny holes might be another challenge, but I’d need to test a small section and see. It will certainly take a lot longer I think. What is the wall thickness of the main structure?
Also what particular challenges did you have last time with the other hub?
It’s useful to know which areas are critical in terms of finish. There is another obvious overhang but I assume that will be largely hidden when fitted in place.
Doing this on an SLS printer is probably going to get you the best results, but at a cost. What sort of delivery time do you have in mind?
Having problems with your STL, got a low-res print on the go now to see how it comes out. My build area is only 15cm high, so I re-scaled your balloon, leaving the screw thread the same size.
Here’s my suggestions so far:
You have a massive polygon count for a fairly simple shape - My computer kept crashing. Using Blender I have applied the ‘decimate’ modifier with a .3 setting to make it more manageable.
Because you have an enclosed shape, whichever way round it’s printed, there will be a lot of support material needed, this is expensive and best avoided. There is a ‘fashion’ in 3d printing to make everything support free - I think this is a bit of a fad, but certainly minimising supports is a great idea.
Your STL is non-manifold - that means there are gaps in the surface - specifically at the top of your balloon - the 8 sections come to a set of points, but they need to come to the same point.
I understand your brief is to design something that can only be 3dprinted… While your shape certainly fits this brief, here are some modification ideas to make the printing easier:
Cut the shape into 8 sections that snap and glue together. One of the great benefits of 3Dprinting is the ability to print functional parts. Then the sections will print largely support free, much quicker, and you can mix and match colours.
The whole piece at 15cm high will take about 13hours to print at low resolution, the separates can still be printed at the same time, but will be much quicker (about an hour each). Also, they can be bigger as many printers have a print area that is longer than taller.
I assume this is a light cover - one of the great things you can achieve with 3dprinting is Lithoplanes (search Google images!). One of the reasons your STL is so complex and takes a long time to print is the holes… If instead of the holes, you varied the thickness of the walls, so the outside would be smooth, and when the light is switched on, the Thames reveals itself. This effect is definitely something for 3d printing and it will simplify your print and make it stronger (so it can be thinner) and quicker to print.
Hey man, thanks for giving this a go. The ideas are great about Lithoplanes, however I have finalised this version of the design as it has now been handed in at university.
How would you suggest to separate the parts to “snap” them together.
