Have sent to the design to a couple local 3D hub printers and they came out poor quality and not waterproof at all. What’s the best material to use to make it waterproof? Thanks.
Hi @Brian_50 it can be very difficult, almost impossible for FDM printing to produce a truly watertight object. Although the surfaces may look solid/sealed, the nature of the technology. There are things that can be done with FDM prints, printing fully solid may help, acetone smoothing of ABS can seal small fissures, coating with a resin such as XTC-3D could work very well, but can be hard to work with (and expensive) and may not leave the finish you’d want (it looks like varnish).
Really you need to look at alternative printing (or production) methods to get something truly, consistently, watertight without lots of post processing. SLA or DJI would be able to achieve it, or you could investigate injection moulding - it really depends how many you want.
In terms of actual “waterproofing”, there isn’t really a material that is better per se. I guess one with better layer adhesion would be better as it would be less likely to fall apart. However, ABS might be a better option simply because it is very easy to smooth it and seal the outside of the box through acetone vapor smoothing. But it really comes down to what other properties it needs, because really any plastic with a good enough print quality would be capable of being waterproof(I have printed watertight and waterproof things with many materials). I would say that at the place where the lid meets the rest of the box, you would likely need a ring printed from flexible materials that would provide a nice seal, for the sheer tolerances on an FDM machine are not capable of producing a watertight seal. I cannot speak for the quality of other hubs, but if you would like, I can give your model a shot on my hub. Here is my link: https://www.3dhubs.com/service/245589 144
Anything printed using FDM will need some additional work to make the materials waterproof. If using ABS, an acetone vapor polish will seal the outer layers and give you a waterproof shell, and will also give you a glossy wet look (which can be turned a little more matte with some light sanding). You can also pick up some clear coat spray paint from your local hardware store, and that will give you a solid shell with a few coats.
SLA will be waterproof from the jump, but some materials will do better than others with prolonged exposure to water. All of this is assuming you are referring to water leaking through the actual walls. If you are talking about the lid, it’s gonna need a gasket.
I have printed many things that are watertight and proof, and I have never used smoothing or coating of any kind. All I do is use 4 perimeters. It works perfectly.
If you print with the right settings you can achieve water tite prints with FDM printers even at the hobby level with consistent results from 1 layer up to thick walls.
Aside from all of the spam and SLA advertising… We print parts for various customers which are used in marine applications, water/fluid flow, fluid pressure measurement, watertite electronics housings and similar things. We can produce watertite prints down to around 127 micron wall thickness.
I’m unsure why your local hubs parts didn’t work or why others here believe it’s so difficult.
If you are looking for strength and underwater (pressure or depth resistant) parts or to contain water (small aquarium) of more than a few ounces you may well need post processing. Generally we use a proprietary method of sealing all internal and external surfaces to achieve this.
You can contact us for further details and material recommendations at soc.3dhubs.link
@Brian_50 perimeter is a setting used in the slicer which tells the printer how it should print an object.
The perimeter setting refers to how many shells (how thick the walls of the print) should be used.
This setting is also dependent on the nozzle/extrusion width used. So for example if you are using a 0.4 nozzle, with a extrusion width of 0.48 mm, 4 perimeters would result in a object with a shell thickness of (0.48*4 = 1.92mm).
I personally would recommend 4 perimeter and then coating it with an epoxy. Especially if you want it to be reliably water proof.
Doing the epoxy coating is pretty cheap and easy to apply.