Printing with PLA a bad idea?

It's very weak and dissolves in water?

Let's revisit these ideas with personal experience

 

History

I've made this enclosure almost a year back, and been riding it ever since. Been through puddles and freezing weather, and also through some rough gravel. You can get it from here.

Never had a problem!

It held whatever I threw at it, the board and the enclosure were rock solid.

 

Now it's time to be smarter looking back at the decisions and design, along with some lessons to improve for the future.

1. PLA?

There's a myth about PLA: it breaks up as soon as you look at it, and certainly not any good for engineering products. And it deteriorates in water

 

I don't share this opinion

 

This thing was wet lots of times, ridden through puddles and mud, and always dried naturally. It met lot's of stones and gravel during rides with grace.

(Also, countless printed bathtub toys for my son later, I'm ok with using PLA with water)

 

The insides stayed warm and dry. Besides several cracks that were well deserved (more on this later) nothing is broken or in any way worse than it was after printing

Dirty and muddy
Dirty and muddy

2. Bedliner

It's my first time using this thing.

It's incredible, after ~800mi not a scratch on it.

Used this one and it's well worth the money, will use it with the next one for sure.

3. Butt-joint between pieces

Bad idea, it didn't work right from the beginning. One of them popped out right at the joint at the first ride. See the picture for the gorilla tape:

Rest of these came loose at some point during the ride. Always fixed with a strip of gorilla tape and held up fine.

And super glue isn't the tool for the job!

 

Needles to say this is fixed in the following revision, all joints are supported by carbon tubes and glued with structural epoxy!

4. Bolts and cracks

Two bolts had cracks around them (see the yellow arrows), all other intact (14 total).

cracks1

Here are some closeups of the broken area.

One:

cracks2_1
cracks2_2

Two:

cracks3_2
cracks3_1

Different things made this happen.

First of all, I didn't use as much foam and padding as I would like (the enclosure was shallow). You could hear the rough road transferred right to the internals.

Will of course improve it with the next installation.

 

Second, the closeness to the rear (the vibrating motor) might helped with these particular bolts being broken.

Material was added to the design, along with rounded edges in the bolts areas.

 

What's next?

The new enclosure is deeper for more padding, and the area around bolts was rounded up and thickened.

As I mentioned above, it has some carbon rods to support the joints.

Several closeups of the new one (before the bedliner):

deeper design
deeper design
Rounded bolts
Rounded bolts

Stay tuned for the surgical transplant of the components from one to the other.

 

Enjoy,

Dani

 

Like what you read? Find it useful? Leave a comment and let me know, thank you.

 

Please subscribe so you won't miss future posts.

Know someone who might enjoy this? Forward this to a friend.

Follow me onĀ  Instagram for more frequent updates

As always, you can email me with any question dani@dosimplecarbon.com