Author Options:

Could a 3D printed sealed speaker enclosure printed as separate parts be bonded together well enough to function properly? Answered

i want to try 3D printing a sealed speaker enclosure but the size of enclosure that i need will be 4 times the size of my printers build space so if i divide the enclosure model into quarters what would be my best method of bonding those pieces together into a container that will be mostly airtight once the speakers are in place?


The forums are retiring in 2021 and are now closed for new topics and comments.

1 year ago

Depends on the type of plastic you're using, FDM parts can usually be glued together with 5-minute epoxy and get an air-tight seal if clamped correctly, not sure about SLA.
For PLA specifically, I'd reccomend using a 3D pen with chamfurs on the edges of the sections, load the pen with PLA and you can use it like a welding torch on metal, completely seamless joint once things have cooled, also lets you fix any minor cracks or flaws from the printing process.


1 year ago

If you use ABS it is dirt simple.
You should still include some grove and tongue system or similar though.
Use a smal jar with a good lid.
Add some acetone into the jar and dissolve ABS pieces.
Does not need to be that much that it turns into a thick good as it is just a gap filler.
If your parts won't mate gap free then make the ABS slurry a bit thicker for the second round.
Using a brush get the slurry onto the parts to be joined.
Give it a quick stroke or two, then join them right away.
Once satisfied repeat the brushing once all is dry again.
The slurry will chemically weld the pieces together.
A thicker slurry with more ABS dissolved in it will be able to fill some small gaps but you need to allow enough time time to dry between applications.
If you can still smell acetone then wait a bit longer.

For PLA woodglue - the white PVA kind works quite well, especially if use the clear drying kind.
Key is to slightly sand the mating surfaces for a better bond and to allow quite some time to fully dry off.
If the surfaces are quite big then it might take up to a week to fully cure.
Abs slurry works fine for PLA as well but does not provide the same bond strenght.

When using ABS slurry it is best to use natural or clear ABS.
Some colors tend to create a white haze when drying while others have pigments in the ABS that just sink to the bottom - avoid using the pigments from the bottom...
If you need a shiny finnish and used ABS throughout then you can put the creation into a sealed chamber or container with some acetone in a open jar.
The vapor will slowly dissolve the ABS on the surface.
You need to check every now and then to remove the acetone and let it all dry off once you are satisfied with the result.
If in doubt try this method first on some smaller parts so you know how to apply it and what to expect.


Reply 1 year ago

so far i've only printed with PLA and PETG and i'd prefer to use PETG as the speakers are for use outdoors and i've been told PLA doesn't cope well with direct sunlight, do you know if there's a suitable bonding agent for PETG?

if PETG doesn't bond well enough and i have to use PLA then is there something i can coat a PLA object with to protect it from degrading outside?


Reply 1 year ago

So far I had no problems with PLA degradation but maybe just because in general I try not to expose plastics to UV light if possible.
Polyethylen does not really bond to anything, even good glues struggle here.
I have a small UHF antenna on my roof with a PLA printed base for the rods and radials.
Sitting there now for about 3 years....
If you want to weatherproof PLA then just give it a coat with some nice paint or varnish.
Preferably something that blocks UV light.