Strength Testing Rig

[Lee Foulkes]

Made some progress on a project (rabbit hole) I got lost in shortly after Xmas. Wanted to share and welcome constructive feedback. Am hoping to make a YouTube video.

It all started with a DJI Osmo Action 5. I’d asked Santa for one. He delivered as usual. After opening I was sad to see there was no fixing for a standard 1/4in tripod mount (or whatever the thread size was). Made my own - nice little design, but it kept snapping at the loop. 

So I inserted some metal staples mid print and it worked much better. It got me thinking, how much better, what else could I do to improve the strength.

Looked on Amazon and got a 20kg load cell and dreamt up a test rig. Tried it with stepper motors first but they struggled to deliver the torque (with the controller board I had spare) so went for a hand drive.

A few improvements needed but i finally got her running tonight on the arduino. Drive on receiver (no part yet). Got it up to 165 Newtons and managed to hold. Need to put some sort of end support on the drive shaft because the force is coming back and causing the gears to grid a bit. 

But not bad for a geologist (well geologist turn waste manager)…..

[markni...@gmail.com]

Lee,

Attached is a video of clough42's tensile strenght tester.

Clough42 always does a workman like job, so it may give you ideas on the best way to procede.

https://www.youtube.com/watch?v=OWH_N9PmjeY&t=335s

[Lee Foulkes]

Thank You. I do like that guy. He’s very knowledgable and his videos are always very clear / well presented. 

[Lee Foulkes]

Back to the drawing board i think. Whilst the PETG part failed at like 160N the PLA Matte (Elegoo) went up past 350N. Which really surprised me. I calibrated the rig with luggage scales and tested those scales with a bucket of water. I only have a 20kg load cell. Going to have to upgrade to 100kg which is a different size shape.

I really thought the PETG was going to be superior in this application. In theory it could flex better than PLA. In all the videos I’ve watched and the stuff I’ve read, I’ve yet to be convinced about the benefits of PETG……

[markni...@gmail.com]

Lee,

While it looks like you have your test jig well sorted out, be aware of the fact that there is no need to use the $500.00 vise, plus $150.00 shipping vise that clough42 used.

Clough42 is an experienced machinest and buys the best (most expensive) of everything.

Vevor sells a comparable vise for $100.00 delivered. The average begining machinest could never tell the difference in practice.

This info is mainly for others wanting to make a tensile strength test jig, as it looks like your is working just fine.

[Lee Foulkes]

Ha another little run tonight. Just printing out some samples for the test day (whenever that comes). Anyhow a DEEPLEE Matte PLA tonight on the Bambu A1 (as apposed to the Sanp U1).

Noticeable weaker in the hand and shows on the rig.

U1  - Elegoo Matte PLA (Black) - 350N+

U1 - Cheap Cheap PETG (clear) - 170 N

A1 - DEEPLEE Matte PLA (Red) - 205 N

Interesting contrast between DEEPLEE and ELEGOO. There are comments online that they come from the same process. They look very similar and are the spools are identical except for brand name.

Not much price difference.

Slightly reduced quality on the DEEPLEE perhaps, different run with grade B or perhaps recycled rejects from Elegoo A line.

Or do you think there could be the influence of the printer? The U1 being enclosed and being able to hold a steady 30C.

[Bryan Eckert]

Nice little test rig. You should test this with some nylon!

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[Lee Foulkes]

Hi Bryan,

You’re right i should try it. Im just a bit apprehensive of advanced materials. I naively tried ABS on my first 3d printer back in 2016/17 ish. A eBay Chinese prusa clone. It didn’t go well. 

I still have the spool of it in the garage and spotted it tonight. Should throw it out really. Parts of that old printer are in the testing rig. Lead screw and linear rails.

It kinda stick in my mind. But I should evolve and get into those materials more, especially seeing as i want to build a voron.0.2 pretty soon. 

[Bryan Eckert]

I will say if you want to print nyon, get a G10 Garolite plate. Makes a world of difference!

To view this discussion visit https://groups.google.com/d/msgid/3d-printing-tips--tricks/d54a7c06-8fe8-4aed-8169-b03c68df61fen%40googlegroups.com.

[Kurt The 3D Printer GUY!!]

Lee - DO NOT Throw out the old ABS - send it to me - I can use it in my Abstracts!!!!!

-K

[Kurt The 3D Printer GUY!!]

Still - Nylon is TOUGH one to print. It's one of the reasons that CF Nylon exists - as it makes Nylon WAY EASIER to print!!!

[Lee Foulkes]

I came to the conclusion that TPU is likely the best filament for this application. It gives the flex for the clamping action and gives good grip keeping the camera steady. It also returns well and will likely be more durable with more iterations before it breaks.

Did a Geetech 95A translucent on the A1mini. it looks quite good as well. Dried for 2 hours at 55C in Creality box. No problems at all on the mini with the Bambu pla settings.

I think it's a very good material for a lot of mounting applications like on bikes etc. 

Learned that Bambu studio won't let you specify TPU and many other filaments when 0.2 nozzle is selected. 

[Bryan Eckert]

I just made some selfie stick holders for my offroad touring bike that snap onto the cargo rack. Ended up using the polypropylene I have. Just flexible enough to snap around the rack, stiff enough to hold onto the selfie stick for my 360 cam. Light, but rugged enough that they'll last forever out in the woods where we go.

To view this discussion visit https://groups.google.com/d/msgid/3d-printing-tips--tricks/8ce1f99b-75e2-4607-ade7-cd9563c94077n%40googlegroups.com.

[Lee Foulkes]

I didn’t know there was a PP filament. Did you put the industry number on it. Perhaps not relevant in the US. Here in the UK/EU its a number 5.

[3D Printing Tips and Tricks]

PP is tricky to print… or more likely finding good PP is what’s tricky. The spool I got has never given me good results.

[Bryan Eckert]

Weird I don't know why it uploaded that small one second clip. I think it was a live image off my iphone.

On Mon, May 11, 2026 at 1:53 PM Bryan Eckert <bigyel...@gmail.com> wrote:

I get great results using a sacrificial PEI plate slathered with Magigoo PP (which seems to eat PEI hence I only use that plate for PP) and cheap Reprapper brand off Amazon ($28).  110C build plate, 60C chamber. 

To view this discussion visit https://groups.google.com/d/msgid/3d-printing-tips--tricks/e944d6cb-4752-459b-aeb6-b0aea06f2930n%40googlegroups.com.

[Bryan Eckert]

Also, the cool thing about PP is that despite being really flexible as a filament it works flawlessly in the AMS, unlike TPU. Probably because it doesn't "squish" like TPU. I just stick it in my AMS HT, run it through the left nozzle on my H2C. Never had a problem at all.

On Mon, May 11, 2026 at 1:53 PM Bryan Eckert <bigyel...@gmail.com> wrote:

I get great results using a sacrificial PEI plate slathered with Magigoo PP (which seems to eat PEI hence I only use that plate for PP) and cheap Reprapper brand off Amazon ($28).  110C build plate, 60C chamber. 

To view this discussion visit https://groups.google.com/d/msgid/3d-printing-tips--tricks/e944d6cb-4752-459b-aeb6-b0aea06f2930n%40googlegroups.com.

[Bryan Eckert]

I think you deleted the message I replied to that had the photos. Here they are

[Lee Foulkes]

Nice. The pp looks good. Looks like it behaves on the build plate.

I’ve lost some energy in the project. 

Work, life - gets in the way. Potching around with 3D printer ain’t gonna pay dem bills.

[Kurt]

Lee - I TOTALLY Hear ya - that is My Struggle as well. I told my Doppelgänger this weekend that if I was Retired like him - I would be doing Intense 3D Design and 3D Printing for 12 hours/day - 7 Days/week!!!

AS for " Potching around with 3D printer ain’t gonna pay dem bills. " - for most folks, that Truly is the case! For me, however, hopefully soon that will No Longer be the case - as my End Game is that my 3DP's May indeed help me to eventually Retire comfortably - via prototype designs I am trying to bring to the world. One of those designs HAS recently been shown here in the forum - including pics of the prototype in Action - including several folks printing copies of the prototype - and even  my Doppelgänger  printing a set for his crazy Barbie Realm Obsession!!!

So - Keep on Rockin' the Print jobs!!!

-K

[Bryan Eckert]

If you can get it to stick you're golden. The problem is, it sticks to absolutely nothing but itself. They actually ship sheets of PP with the filament you're supposed to tape down and print on. But of course, those warp because they melt.

You also can't use any cooling fans, as it will literally blow off of the print plate. I turn off all fans.

The Magigoo PP is awesome. It's some sort of witches brew, I think it's a blend of PP and PEI. But it destroyed that print plate when I tried to scrub it off.

To view this discussion visit https://groups.google.com/d/msgid/3d-printing-tips--tricks/fc7d8bd8-3c5b-42a3-838e-8eace8b55be7n%40googlegroups.com.

[Kurt]

I'm curious. In regards to what you wrote - "They actually ship sheets of PP with the filament you're supposed to tape down and print on" - how did you actually try to tape it down??

-K

[Lee Foulkes]

K - I truly hope you can get there. It’s more than 10 years away for me (retirement) and I’ve worked on multiple landfill sites for 25 years so have a slight exposure disadvantage.

[Bryan Eckert]

You can just tape it with masking tape.

To view this discussion visit https://groups.google.com/d/msgid/3d-printing-tips--tricks/17c7c137-4892-47f3-993c-d71411404eeen%40googlegroups.com.

[Kurt]

Dang - the Exposure thing sounds Bad! And, 10 years - you got a ways to go. I'd like to retire in 2-3 years, and when I do - get my Arse back down to Sunny SoCal!!!

-K

[Kurt]

I think the masking tape may NOT be the proper way to do it. 

Years ago when at SD3D - and the boss man was making his own build sheets - it was like flexible steel sheets - and he would adhere his special brown sheets onto to it with this special double side 3M sheets - they are like thin films of Glue - and a total PITA to use and implement. I think THAT is what you should really be using to use those PP sheets! 

Just sayin'...

-K