On 09/05/2019 09:32, Nightjar wrote:
On 08/05/2019 17:14, Peter Parry wrote:
On Wed, 8 May 2019 14:09:09 +0100, Bill Wright
wrote:

I've been making some components using glass fibre, finished with car
body filler. They are caps, covers, and adaptors for various sizes of
tube. They will be installed outside so must be durable, waterproof, and
quite tough. The ones I've made are entirely satisfactory except for one
thing: it takes too long to make them. So, I was wondering about 3D
printing. Are the products from these tough, waterproof, and UV
resistant?

Of the two common printing plastics PLA is tough and waterproof but
most certainly not UV resistant, it is biodegradable.Â* Polycarbonate
is tough and stable but is more idly to print with and requires a
higher printing temperature and a heated build plate for best results.
It is also very smelly when printing.

Polycarbonate is not naturally UV resistant. Polycarbonate glazing has a
UV resistant coating. A house I used to own had a conservatory where the
previous owner had put some polycarbonate hollow section roof sheets on
the wrong way up. Those sheets were like Swiss cheese, while the others
were still sound.

I would go for ABS or nylon for outdoor use.


ABS can be quite tricky to print with if its a big part and no heated
chamber.

If being a bit brittle doesn't matter then I would just spray PLA with
an etching primer.

You can anneal PLA in an oven and make it tougher and more heat
resistant according to other, I have never tried it as I tend to print
non-structural models.
Apparently it shrinks a lot when you do it so some trials would be
needed to get the dimensions correct.