Can I print with low density polythelene (LDPE)? If not, what's a similar material
 
Notifications
Clear all

Can I print with low density polythelene (LDPE)? If not, what's a similar material  

  RSS
topdotter
(@topdotter)
Active Member
Can I print with low density polythelene (LDPE)? If not, what's a similar material

Looking to print malleable plastic saline vials that I can fill with a liquid and seal. Like these: https://www.google.com/search?q=saline+tubes+for+nebulizer&sxsrf=AOaemvKm0B754FkFf9gAAylMLssZx3INhQ:1633456835886&source=lnms&tbm=isch&sa=X&ved=2ahUKEwi9qNXz7LPzAhWalGoFHZCxA-wQ_AUoAnoECAEQBA&biw=1536&bih=722&dpr=1.25

I'd want to print them with the twist off cap and keep the bottom open for filling, then using a separate process crimp or heat seal the bottom closed.

  1. What material can I use that would be similar enough for prototyping. Squeezable, twist-off top, sealable once filled. Transparency is not important, nor is food-grade or sterility a requirement.
  2. What orientation would you recommend printing them? I'm having trouble picturing the best way to create the void and also to create the twist off top.

Thanks!

Posted : 05/10/2021 6:05 pm
Xanthe
(@xanthe)
Trusted Member
RE: Polypropylene...

... is printable and available as a printer filament.

Finding a good material for the bed for use with alkane materials is something of a problem though (they don't stick to much and not much sticks to them!).

Posted : 05/10/2021 11:30 pm
Dan Rogers
(@dan-rogers)
Noble Member
Not a good fit for FDM

It's gonna be near impossible to print a water tight container.

Posted : 06/10/2021 7:20 am
Area51
(@area51)
LDPE not a good printing material

Back when 3D printing began for hobbyists, PE (Polyethylene) was used as it was available in 3mm rolls for welding applications (I have a roll somewhere).

But it has major 3D printing problems, as it will only stick to itself, has high thermal expansion leading to warping and is hard to squeeze through the nozzle (viscosity). Otherwise a great material, inert to chemicals, has a low price and is not brittle.

It was given up in favor of ABS and later PLA.

Have a look at my designs on Thingiverse or on PrusaPrinters ;)...
Posted : 06/10/2021 11:12 am
towlerg
(@towlerg)
Noble Member

It's gonna be near impossible to print a water tight container.

Not sure if thats true. There an article in the Prusa database about the ability of different materials to print water tight objects.

IIRC Theres a YouTube re post-processing by embedding the parts fine sand and baking.

Posted : 06/10/2021 12:53 pm
Area51
(@area51)

YouTube video: 3D Printing with HDPE - Successful Print Using Cold HDPE Build Plate

Have a look at my designs on Thingiverse or on PrusaPrinters ;)...
Posted : 06/10/2021 1:23 pm
Diem
 Diem
(@diem)
Noble Member

I'd want to print them with the twist off cap and keep the bottom open for filling, then using a separate process crimp or heat seal the bottom closed.

Watertight objects tend to require more perimeter layers but twist off caps need fewer, this is not an easy FDM print.

What material can I use that would be similar enough for prototyping.

PETG might do for first tries 'though TPU/flex is more likely to meet the design criteria.

What orientation would you recommend printing them? I'm having trouble picturing the best way to create the void and also to create the twist off top.

Twist off end first: you may need a skirt to hold it in place for later layers.  Keep the shoulders of the main container at 45 degrees and it should print OK.

You might experiment with vase mode and a wider extrusion.

Cheerio,

Posted : 06/10/2021 1:59 pm
Share: