Quality of 3D printed thread dial

R

RWanke

Registered
Registered
Joined
Aug 23, 2017
Messages
183
I am just about done with all the clean-up and painting on mySouth Bend 9C and about all I need parts wise to finish it up is a thread dial. The originals on E Bay are way out of my budget for this project and so I have been looking at the 3D printed ones over there. Does anyone on here have any input as to good or bad traits of using these plastic replicas? Are they reliable as to gear teeth staying engaged, not slipping or jumping teeth, etc. I have zero experience with anything 3D printed so I'm venturing into the total unknown here. Any input or advise/direction would be appreciated.
 
3d printing materials vary drastically due to the process to print. Even the material strengths very drastically. In my experience of prototyping and production using 3d methods nylon will be the strongest material when printed with SLS-select laser sintering. Any FDM process will be very weak.

Any metal type 3d printing will be more expensive of course. There is a binder jet method that uses stainless steel and bronze which can have good wear characteristics. The stainless bronze mix will be cheaper than aluminum and hold up to abuse.

I would recommend researching:
-what material is used
-what process to print
 
Manderioli said:
Any FDM process will be very weak.
Click to expand...

FDM Nylon is very strong, I'm prototyping a pistol target rear sight in Nylon and one of my demonstrations to a friend who commented on low strength was to drop it on a concrete floor and stamp on it as hard as I could, five or six times, with the heel of my leather soled shoes.
Result? Light surface marking and no loss of function or measurable distortion.
When playing with my printer to see what it could do I printed functional M5 x 25 bolts in PLA, I'm no weakling but I couldn't snap them with my fingers, I carried one in my pocked for a month and none of my friends or acquaintances could break it with their fingers either.
FDM was a lot weaker several years ago but hardware, firmware and code generation (slicer) software have all moved on from there significantly.
You should watch Thomas Sanladerer's You Tube videos on FDM material strength testing to drag your view of FDM kicking and screaming into the 21st Century ;-)
Regards,
Nick
 
Here is a video describing the main processes of 3d printing plastic:


The main factor to longevity and structural integrity is the direction of the layers when printing.

The 3d printing technology is advancing quickly. You may also want to research how the part was produced. Some people will only print the outside shape with structural supports inside which is a great way to reduce weight without comprising strength. While others will print a solid (filled in) part. A solid part will cost more due to material and time to make.
 
That's the most Shonky materials test I've ever seen in my life, if he'd tested a Taulman Bridge Nylon part FDM printed at the same density as his laser sintered part it would have performed just as well.
That video proves only that without scientific method you can "prove" what you like to those who can't see the failings in your test method, at the very least he should have been printing Clay Pigeons at matching weights and using a launcher to apply consistent impact force and angle, I laughed my socks off when the clown had someone else throw a part to add an impossible to guess variable to his test! :D

Again, check out Thomas Sanladerer's FDM materials tests, he uses set part size and shape, the same densities of print and the application of measured bending forces, repeatable impacts and set heat application for tear tests
 
I agree the test is not truly valid nor will the original posters part face the same extreme tests or abuse.

I will look into Sanladerer’s videos to expand my knowledge.

——
Also consider what type of machines are making the components you seek. There is a large range of machines from a simple desktop to industrial machines. The cheaper versions may be great for prototyping a concept but not for daily use. Industrial machines are tailored for faster production and mass production.
 
Having printed a lot of things and worked with a number of them in somewhat tough situations, I don't think a thread dial would be problematic. There's almost no force on the thing, just the gear being pushed by the lead screw. It's usually a lower speed operation, so friction heating isn't a big issue. Even PLA would likely be just fine. The biggest issue would be surface finish and accuracy. Those can mostly be handled by properly adjusting your printer and slicer settings.

If you can do ABS, you can use acetone to smooth it, but that can be problematic in some ways. I'd probably use whatever was loaded in the printer, then sand it if needed. Use small layer heights, and do some test prints to make sure layer adhesion is good. Done properly, FDM can be nearly as strong as the base material. When I set mine up, I make sure destructive testing does not break on layer boundaries. Sure, it's still plastic. But it doesn't have to be weak.

My printer is a Lulzbot Mini. I haven't inspected parts from other machines, so I can't say if they are better or worse. But reports from other people on printing forums indicate that if you set things up right, there isn't a huge difference in strength from printer to printer.
 
You must log in or register to reply here.
Back
Top