New to the RP idea, some advice?

Hey guys.

I have been seriously thinking about purchasing a RP for a few weeks now, and i would like to get some advice. I am not too comfortable with the idea of building my own reprap, and i have seen some others such as the MakerBot Replicator 2 that are a "print out of the box" option, which appeals.

But one thing i need to make sure of is this. If i was to build a manifold used to direct a constant water flow, built with PLA, will be it water tight? The pressure wont be very high, sort of thing you would find coming from a standard submersible aquarium water pump. I am worried that since it is built is layers, these might not bond properly and cause leaks. The same goes for forming a small tank. The thickness isnt a problem, could go for a nice 1mm thick wall, but could really do with knowing how secure it will be.

Also, how easy is PLA to polish? I would like to get some nice finishes for that injected plastic look. maybe a coating that wont chip/wash off?

And has anyone ever had any water problems, such as contamination or changing PH values?

Thanks guys.

For me I don't like moisture touching PLA and if you mix pressure and any sort of heat it is bye-bye time. In the southern USA PLA will not last through the summer (edit: if outside) and if you want it to remain water tight you might get a month out of it here. ABS will easily handle what you want but if PLA or ABS use some marine grade varnish on it to protect it even more (from UVA/UVB and moisture).

Edited 1 time(s). Last edit at 12/19/2012 12:44AM by Dark Alchemist.

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I await Skynet and my last vision will be of a RepRap self replicating the robots that is destroying the human race.

Thanks for that! That is a real shame. It wont be outside at all, nor exposed to temps above about 40C, but it not being water tight, that is a big problem for me. Seems like the technology is kind of limited. Shame really.

... for use in wet/humid environment you should print with ABS.

You can soak the parts with a paste made from ABS solved in acetone to close small holes ... and/or put the printed part some hours in a box with acetone vapours to 'smooth' the surface for a neraly perfect finish ...

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Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

VDX Wrote:
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> ... for use in wet/humid environment you should
> print with ABS.
>
> You can soak the parts with a paste made from ABS
> solved in acetone to close small holes ... and/or
> put the printed part some hours in a box with
> acetone vapours to 'smooth' the surface for a
> neraly perfect finish ...
Yep, but I had never heard of the vapour trick as that is a new one on me. Now when you say "some" hours about how long is that or is it dependent upon some external factors?

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I await Skynet and my last vision will be of a RepRap self replicating the robots that is destroying the human race.

... ye longer, the more 'smoothed' is the surface, but depends on ambient temperature and vapour concentration too - some put it over night in a closed box together with a dish containing acetone ...

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Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

That sounds cool but I would be afraid it would melt it into a glob of goo by morning, lol.

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I await Skynet and my last vision will be of a RepRap self replicating the robots that is destroying the human race.

Slimer Wrote:
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> Thanks for that! That is a real shame. It wont be
> outside at all, nor exposed to temps above about
> 40C, but it not being water tight, that is a big
> problem for me. Seems like the technology is kind
> of limited. Shame really.
I had to come back and answer this because it has been gnawing at me all day. If you mean the 3d printing technology that isn't the fault at all and you can't really blame the PLA either since it is, basically, corn starch and water. This is why the plastics industry has all sorts of different materials to work with based on what its final purpose will be.

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I await Skynet and my last vision will be of a RepRap self replicating the robots that is destroying the human race.

Dark Alchemist Wrote:
-------------------------------------------------------
> Slimer Wrote:
> --------------------------------------------------
> -----
> > Thanks for that! That is a real shame. It wont
> be
> > outside at all, nor exposed to temps above
> about
> > 40C, but it not being water tight, that is a
> big
> > problem for me. Seems like the technology is
> kind
> > of limited. Shame really.
> I had to come back and answer this because it has
> been gnawing at me all day. If you mean the 3d
> printing technology that isn't the fault at all
> and you can't really blame the PLA either since it
> is, basically, corn starch and water. This is why
> the plastics industry has all sorts of different
> materials to work with based on what its final
> purpose will be.


I never said it was at fault, i said it was limited, which it is. If the printer cannot utilize other plastics, then it has a limit. Therefor, the technology is limited. It is an amazing technology, but so was the CRT based TV when it came out. Now look at them I am sure they will be able to implement different materials soon.

2nd attempt to get my response to take on an otherwise pretty overloaded forum.

The problem isn't the printer it is that only so few materials are in filament form. The printer will print even metal so I know it isn't a printer issue. Now what is available is a machine to make your own filament out of recycled plastic and using pellets. You can get almost every material you would need in pellet form whereas we are stuck with primarily two (ABS and PLA) but there is a couple of more just not overly used.

So, the technology is there just the manufacturers are not producing the filament for us and getting pellets (used in injection molding) to work with this has been tried but lots of failures due to several factors but mostly with flow.

By the way pellets are butt cheap whereas filament is pretty costly in comparison.

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_______
I await Skynet and my last vision will be of a RepRap self replicating the robots that is destroying the human race.