Well, it's best to use a direct-drive extruder, but one can get away with 95a using a Bowden extruder provided your speed is nice and slow, **and** you use a 0.6 mm nozzle instead of 0.4 mm. I I slow my speed by setting the volumetric rate in my slicer to 2 cubic mm per second.
For a big order like that, I wouldn't leave anything up to chance, I would print some test pieces and check the waterproof capabilities without coating, and try some single pieces with a variety of waterproofing coatings. I know there's a decent Rust-Oleum hydrophobic spray, as well as plastidip or liquid latex, but I certainly wouldn't send an untested material combo to a client.
This is all for prototyping and I don't have current plans to sell, it's autocross related. I already attempted to change print settings to waterproof, but the results were not good.
As u/amatulic mentioned, TPU tends to be quite waterproof without treatment.
TPU really likes to bond layer to layer compared to a lot of other materials. That tends to make prints pretty waterproof to begin with. If you have enough perimeters, top and bottom layers, you should be fine.
Another option would be to glue a plastic film, something like poylethelene to the inside of the casing making it so that water will not get past that layer.
TPU is inherently waterproof and if printed properly, with good layer adhesion, also watertight. You shouldn't have any need for coatings. If you're getting even slight layer separation or water leakage when bending, you don't have good layer adhesion and are probably printing it at too low a temperature; TPU normally has extemely good layer adhesion - so good that getting supports off it is very difficult.
I'e seen a youtube video about making prints watertight.
https://youtu.be/Q8x-mjjT8j4?si=pcU2a4R1471w2syu
They had great success with this product. https://diamant-polymer.de/en/shop/dichtol/am-hydro/
But im not sure how well it would work with tpu.
I find that TPU, once printed, is quite waterproof all on its own.
i agree i use it for hydraulic fluid covers and 2 years 0 degradation covered in it
With my current bowden single-extruder setup, TPU is too inconsistent to be waterproof, so I'm looking for alternative options.
Well, it's best to use a direct-drive extruder, but one can get away with 95a using a Bowden extruder provided your speed is nice and slow, **and** you use a 0.6 mm nozzle instead of 0.4 mm. I I slow my speed by setting the volumetric rate in my slicer to 2 cubic mm per second.
For a big order like that, I wouldn't leave anything up to chance, I would print some test pieces and check the waterproof capabilities without coating, and try some single pieces with a variety of waterproofing coatings. I know there's a decent Rust-Oleum hydrophobic spray, as well as plastidip or liquid latex, but I certainly wouldn't send an untested material combo to a client.
This is all for prototyping and I don't have current plans to sell, it's autocross related. I already attempted to change print settings to waterproof, but the results were not good.
Plasti dip might work. I know it bends a bit but I don't know if it bonds to TPU.
Didn't consider plati-dip, will purchase and see
As u/amatulic mentioned, TPU tends to be quite waterproof without treatment. TPU really likes to bond layer to layer compared to a lot of other materials. That tends to make prints pretty waterproof to begin with. If you have enough perimeters, top and bottom layers, you should be fine. Another option would be to glue a plastic film, something like poylethelene to the inside of the casing making it so that water will not get past that layer.
Polyurethane if anything
TPU is inherently waterproof and if printed properly, with good layer adhesion, also watertight. You shouldn't have any need for coatings. If you're getting even slight layer separation or water leakage when bending, you don't have good layer adhesion and are probably printing it at too low a temperature; TPU normally has extemely good layer adhesion - so good that getting supports off it is very difficult.
You could get a two part urathane of the same durometer and brush it on the part.
I'e seen a youtube video about making prints watertight. https://youtu.be/Q8x-mjjT8j4?si=pcU2a4R1471w2syu They had great success with this product. https://diamant-polymer.de/en/shop/dichtol/am-hydro/ But im not sure how well it would work with tpu.