Alternative to PLA  

RE: Alternative to PLA

Up until 6, ABS is a slam dunk for your needs.  I would hesitate to lick a PLA print more than once (musical instrument) - you'll never get it clean.  And it will melt if you leave it in your car.  Easy to print is subjective.  I find everything easy to print, but when I was starting out, I could not get anything other than PLA to print.  It's a learning curve.  And for ABS it's you need an enclosure with a fume elimination solution.  I used to be afraid of PETG (ruined a couple of smooth sheets until I learned you need to use a release agent).  And ABS even more so - but many coats of VO5 Purple, or one coat of Lamineer, and it's just a different Live Z setting and a vented fume capture hood.  For hardness - ABS has it all over PLA in every dimension.  PLA is tempermental in sunlight, hard to make waterproof, and unless you learn you can glue it with acetone, nigh impossible to glue parts together. 

RE: Alternative to PLA

thanks @dan-rogers - just a further comment, as for leaving in the car any instrument will suffer due to the use of glues that softened in heat (which is an instrument prerequisite for enabling repairs). Also PLA does glue with polyurethane.

RE: Alternative to PLA

PETG is the best option.  Not perfect, but the best.

RE: Alternative to PLA

@cwbullet Thanks - in my opinion PETG fails the strength/hardness criteria

RE: Alternative to PLA

@john-6

I don't disagree.  I just don't think there is a perfect option that is "easy to print".  

RE: Alternative to PLA

easy to print is my last criteria of importance. the physical properties are paramount

RE: Alternative to PLA

How about petg with Carbon Fiber?  Or Nylon with Carbon Fiber?  

RE: Alternative to PLA

@cwbullet indeed. I guess that is the nub of my question. I am quite happy to use a carbon fibre option. Any thoughts which fulfilled my parameters.

CF based Nylon or PETG or even polycarbonate?

RE: Alternative to PLA

There are various CoPA and variants like Colorfabb nGen that are worth a look. Quite nice to print with and a bit more durable than PLA. 

RE: Alternative to PLA

Colorfabb nGen is stronger than PLA and rather easy to print.  I do not know of a filament that had the Galaxy type appearance and all of these features.  I do know that there are PLAs and PETGs that have carbon fiber in them.  I used them in rockets and they are strong.  They have decent temperature resistance.  What temperature will the parts be exposed to and what environment?  

RE: Alternative to PLA

I started this printing journey to make a musical instrument thinking I would make prototype shapes to replace with aluminium or metal later.

When used in conjunction with some alum supports , in most aspects PLA exceeded my expectations and am now looking to maximise the use of plastics. Because PLA is actually quite brittle and snaps rather the stretches before failure it is suiting my purpose as parts which take string pressure are transmitting the sound to the structure amazingly well. ie: is it has sustained sounds clear and clean. I expect the instrument to be looked after and used in normal heat environments like any wooden instrument. PLA softening I believe starts at about 60C so if left in a car would be a problem but so would any instrument but more temperature headroom would be ideal.

@cwbullet and @bobstro Colorfabb nGen is "durable and stronger" - Durable is not so much an issue (being an instrument) but the right type of Stronger is as I need something with minimum creep, stretch and deflection. Its tensile strength is not so important as I can design in the strength with more material. Ideally it feels solid like PLA for the sound transfer.

CF PLA or CF PC or maybe nGEN sounds like they might be ideal. I'll check the densities,

RE: Alternative to PLA

IF creep is an issue then stay away from the carbon filled stuff.  Steffan from CNC Kitchen recently did a video about creep on his Voron parts and the filled plastic was much worse for creep.  Might want to look on youtube for it as he tested various plastics for creep.

RE: Alternative to PLA

@neophyl interesting as fibres should prevent movement but I guess depend on the direction of the creep. Also Some CF is only a powder which wouldn't do much. do you have a link? thanks

RE: Alternative to PLA

It is difficult to beat PLA for musical instruments, in high fill percentages it behaves (musically) very like some woods.  Coating with acrylic laquer or (food grade) epoxy resin can pay off for woodwind.

Eg: These were printed at 100% fill and just dipping the mouthpiece is enough.

minimal long term degradation

... and PLA is unjustly reputed to be short lived. I have PLA parts that are over 7 years old with no detectable signs of aging.

Yes PLA will deriorate quickly in ultraviolet light so keep it covered.  It does not dissolve in water.  It is, slowly, biodegradable but unless it is hot composted it lasts for years, decades, in temperate climates.

have my eye on chopped carbon fibre blends

In most cases making the part a little thicker is enough for strengh and stiffness, CF is expensive, tricky to print, and best reserved for technical parts that cannot be redesigned for strength - I might consider it for a stringed instrument which will apply considerable bending stress but its probably better to use a section of woven CF tube as a reinforcing insert that won't creep.

Other than PLA, ASA is probably your only readily available alternative although warping will be a problem, ABS is worse, both can be smoothed with acetone vapour instead of coating.

Cheerio,

RE: Alternative to PLA

@diem thanks - I seem to be agreeing with you that PLA has good resonance. what you also say is right as I have been using other materials including alum and carbon fibre sheets where minimal movement is imperative. Also leaving an instrument out in the sun is not a good idea so im not worried about UV.

Have you had any issues with temperature affects?

RE: Alternative to PLA

hlo

RE: Alternative to PLA

If you plan to leave them in a car, PLA is not a good choice as you said.  This article may help:

https://3dprinterly.com/will-pla-petg-or-abs-melt-in-a-car-or-the-sun/

They recommend PC.  A PC Blend may also work.  Although not the easiest to print, they are not by any means hard to print.  

RE: Alternative to PLA

Some misconceptions about PLA:
All PLAs if annealed will withstand very high temperatures, more than most other easy printable plastics. (If not annealed it can become soft in temperatures over 50-55ºC)
It does NOT degradates with time if it is reasonable quality.
It is one of the most stiffness/strongest materials you can print easily in a hobby printer. (But that stiffness makes it brittle)

Sometimes that characteristics are not the required ones for some projects. But there is the option of what manufacturers call PLA+. PLA+ is enhanced PLA in some way or another.
The problem is that every manufacturer of PLA+ has its own recipe and they characteristics vary from one to another.
I have used 2 kinds of PLA+ with very good results:
- PLA+ from Sunlu it is much more sturdier than normal PLA and resista a little higher temperatures. (It is much stronger than ABS, PETG, ASA and others and much more impact resistant than those)
- Volcano PLA from Formfutura it is sturdier than normal PLA and very high temperature resistance. (Without annealing it supports higher temperatures, if you anneale it then that characteristic is enhanced to the maximum)
They print as easy and accurate as normal PLA, they just need a bit higher printing temperatures.

RE: Alternative to PLA

@gonper

What temperatures can it withstand without softening?  In the SE USA, temps can reach 50-60C in a car.