A repository of 3D print STL sources

[jlcnuke]

Ah, you must stop the print to put on the snap bolt?

I was initial stopping then resuming the print to put it in, but I found I could get a layer right there that didn't bond well if I let it sit too long. When oriented right, I could instead place the bolt snap in as it prints in another area of the design. That method eliminated the poorly bonded layer issue and made me pay attention to it more closely during that period of the print, so that's what I'm currently doing.

 

[rob.mwpropane]

I was initial stopping then resuming the print to put it in, but I found I could get a layer right there that didn't bond well if I let it sit too long. When oriented right, I could instead place the bolt snap in as it prints in another area of the design. That method eliminated the poorly bonded layer issue and made me pay attention to it more closely during that period of the print, so that's what I'm currently doing.

 

[ScubaToneDog]

I have found that PLA+ works very well for outside use.

PLA+ varies from manufacturer to manufacturer. I use Inland and its pretty tough stuff. It has a mix of PLA and ABS so it prints easy with no warping. I have made some parts for my picnic table and deck that have spent a full year in the elements (spring, summer, fall and winter). Parts have faded slightly, retained their flexibility and have not warped. While I wouldn't trust any of it for life and safety products, it will safely hold your camera, bolt snap or serve as a line cookie just fine.

I've made a bunch of these clips from PLA+ and they hold up to 200lbs before failing. Regular PLA gives up around 100lbs.

Lex

 

[rob.mwpropane]

I have found that PLA+ works very well for outside use.

PLA+ varies from manufacturer to manufacturer. I use Inland and its pretty tough stuff. It has a mix of PLA and ABS so it prints easy with no warping. I have made some parts for my picnic table and deck that have spent a full year in the elements (spring, summer, fall and winter). Parts have faded slightly, retained their flexibility and have not warped. While I wouldn't trust any of it for life and safety products, it will safely hold your camera, bolt snap or serve as a line cookie just fine.

I've made a bunch of these clips from PLA+ and they hold up to 200lbs before failing. Regular PLA gives up around 100lbs.

Lex

Exactly what I use, Inland PLA+

 

[jlcnuke]

I'm working out a new finger spool similar in basic design to the newer OMS spools, as I really like the concave finger "grip" on the ends. First prototype is printing right now. If I get the settings working well I'll post that one to Thingiverse as well and put a link.

Getting the threads right to put the two pieces of the spool together wasn't the easy part, but once I decided to make them in Fusion 360 instead of Tinkercad it was simple (not sure why Tinkercad screws up threads so badly, but it's just terrible trying to do threads with it and get them to print right). Got the first test print done last night and it worked out pretty much exactly as I'd hoped. File is now up on Thingiverse here.

 

[rob.mwpropane]

Getting the threads right to put the two pieces of the spool together wasn't the easy part, but once I decided to make them in Fusion 360 instead of Tinkercad it was simple (not sure why Tinkercad screws up threads so badly, but it's just terrible trying to do threads with it and get them to print right). Got the first test print done last night and it worked out pretty much exactly as I'd hoped. File is now up on Thingiverse here.

View attachment 650791

View attachment 650792

View attachment 650793

That's awesome, thank you!

 

[OTF]

Posted this spool a few weeks ago on Thingiverse and /r/scuba -- didn't even know we had a fabrication forum here until today.

"Not super-amazing, but I'm pleased with the design modularity and printability, and with some of the design choices.

There are quite a few jump spools on Thingiverse, but I didn't love the designs: they required supports, or required load-bearing gluing, or didn't offer good ways to tweak the line capacity, or etc., so: created this from scratch.

I have successfully printed these in PLA, ABS, TPE (NinjaFlex), and TPU. (TPU is actually a pretty good choice, since it will flex rather than crack if it gets smashed between tanks, etc. TPE is a little soft, but also okay.)

Most of the subcomponents use about 5m of material, so if you have samples lying around, this is a handy way to use them."

Thingiverse: Jump Spool / SMB spool (SCUBA) by lairdb

Imgur gallery: Imgur

I made some modified versions of this brilliant spool design. I thickened it for strength, widened it, modified the middle shape to hold more line, and probably a few other tweaks I forgot. The ABS acetone vapor-smoothed version came out gorgeous and has been pressed into service. This holds something like 175ft.

 

[OTF]

This is a dump string knob I designed for a friend that has hard time with just string. Dump knob link

I remade some cookies to be smaller than the "standard" size. Cookies link

I also made a smaller REM marker. REM link

I'm working out a new finger spool similar in basic design to the newer OMS spools, as I really like the concave finger "grip" on the ends. First prototype is printing right now. If I get the settings working well I'll post that one to Thingiverse as well and put a link.

I'm also working on finalizing a design for a boltsnap-to-gopro underwater housing adapter currently. Might actually see if I can sell a few of those eventually as I'm liking the prototypes so far. Here's a pic of an early prototype:

View attachment 650235

I've been using PETG for all my prints for stuff to be used underwater, as the limited water absorption and increased strength over PLA seemed like it would make a good option. What's everyone else using for these kind of things?

Constructive criticism: I'd worry about the boltsnap ring snapping along the layer lines. Davy Jones already has way too many gopros in his locker. Maybe add some fillets and thicken it up? I would say to print it in an orientation with the hole vertical for more strength but it would be impossible to put the boltsnap in. That might require a two part design. Or using a bit of cave line to tie the snap in.

In theory this is true, but reality is whatever we print will only see such a small time underwater. I don't think it's as much a concern as I did before.

After my 1st model started to crack (I think it was 60% infill, 3 walls) I cut into it to see if there was any moisture. I couldn't find any.

My new model was printed with 80% infill (to me 100% is past the point of diminishing returns). You can look up cross sections of 80% vs 100%. No a lot of difference structurally, but 100% takes a bit longer to print. Just sharing my experience.

So far no issues at all.

The one downside to PLA is you can't let it get hot, so a hot car or dive box would let it change shape a little.

One other thing I forgot I use every dive is a long shaft that stays on my belt to stow the long hose. Works pretty well, 80% infill PLA. If I do it again I'll probably make it longer.

Not a lot of difference structurally... but parts less than 100% infill can and do fill with water. Seen it happen frequently. Although you might not care and it might not matter depending on the application. Even 100% infill parts will absorb some water if you do a before+after test by weight. Especially Nylon. But again I've used nylon parts underwater and they work fine for most things.

Printing hollow parts with drain holes is an option, like the gun-shaped long hose retainer I posted in the other thread. Hollow voids filled with epoxy or dense foam is another option.

I've spent a lot of time researching and testing ways to make better prints for underwater use. I should write up a longer post with more of a guide. But generally I try to do everything I can to get layers fully fused, both to eliminate porosity and to increase strength. That means printing 100% infill, hot, slow, in a warm chamber. I increase extrusion a bit and use an infill extrusion width >100. This creates higher nozzle pressure that helps fuse layers and minimize horizontal voids. Also lots of tweaks to make sure the slicer isn't leaving any empty spaces like carefully tuning "thin wall behavior" settings. I print ABS and PETG.

 

[The Chairman]

I should write up a longer post with more of a guide.

Tapping fingers on my desk waiting for this.

Waiting...

Still waiting...

You typing yet???

 

[jlcnuke]

Constructive criticism: I'd worry about the boltsnap ring snapping along the layer lines. Davy Jones already has way too many gopros in his locker. Maybe add some fillets and thicken it up? I would say to print it in an orientation with the hole vertical for more strength but it would be impossible to put the boltsnap in. That might require a two part design. Or using a bit of cave line to tie the snap in.

Thanks for the input. I did worry about strength some so I did a test on the first couple designs. The initial pull tests I did for strength failed around 48 lbs when pulled directly against the layer lines (failure was both at one or both of the GoPro mounts and the bolt-snap area pretty much simultaneously - first test one gopro mount and the boltsnap retainer and the second at all 3), but now I'm printing at a ~30° angle and FDM performs better in strength when printed at an angle relative to the force applied so I expect it would hold even better now (though I haven't tested them yet).

Either way, if you're putting 50+ lbs of direct pressure against a GoPro you should probably be expecting to break something imo. The one GoPro I lost broke off of a wrist mount at the connectors as well (hit it against something getting back on a boat in PDC, not even hard enough to notice it but it was there when I was floating in the water and gone when I was sitting in the boat). I'm sure there are ways to make the bolt-snap more secure but I can't think of how to make the GoPro connectors more secure with the limited space to work with. Overall, I'm pretty confident that it's about as secure as just about any other typical GoPro attachment commercially sold right now.