1 Topic by tjhering

  • tjhering
  • Newbie
  • Offline
  • Registered: 2014-01-30
  • Posts: 5

Topic: material hardness questions

Greetings! I am an engineer in a metal forming plant and have a question about 3d printing materials. We have polyurethane rollers that feed sheet metal through a machine. These are coated in polyurethane with a hardness of 90 on the A scale. If we were to purchase a 3d printer to print our own rollers, is there a material filament available that matches this hardness? Perhaps the real question is will this material be as durable as polyurethane. If so where could this be found? Any info would be great!!!

2 Reply by adrian

  • adrian
  • Member
  • Offline
  • From: Canberra, Australia
  • Registered: 2013-01-15
  • Posts: 1,623

Re: material hardness questions

Can always print the bulk of it and then polyurethane dip them.

3 Reply by tjhering

  • tjhering
  • Newbie
  • Offline
  • Registered: 2014-01-30
  • Posts: 5

Re: material hardness questions

A good idea and would work in most applications. However the roller must be stretched over a shaft and fit snuggly to keep from sliding. Although using an adhesive is an option as well so your method might work.

4 Reply by tjhering

  • tjhering
  • Newbie
  • Offline
  • Registered: 2014-01-30
  • Posts: 5

Re: material hardness questions

Any experience with ninja flex ?

5 Reply by adrian (edited by adrian 2014-01-30 01:38:06)

  • adrian
  • Member
  • Offline
  • From: Canberra, Australia
  • Registered: 2013-01-15
  • Posts: 1,623

Re: material hardness questions

Not ninja flex, but the other version EcoFlex which has been around a while.
To paraphrase and misrepresent a quote from a famous film about space (LOL):
"<waves hand> These are not the materials you are looking for."

With no clue what so ever at all about specifics or purpose, my suggestion from behind a keyboard would be (i.e, dont consider this constructive advice, just musings aloud.....) :
Nylon (618/645 depending on desired mech strenghth) - for its flex properties (its friction co-efficent in this instance being a negative) + Polyuerthane dip would be the best bet... slightly under-sized ID relying on stretching the nylon and then an appropriate polyuerthane dip (or two... base dip + hard coat)...

6 Reply by grob

  • grob
  • grob
  • Member
  • Offline
  • From: Sydney, Australia
  • Registered: 2014-01-02
  • Posts: 900

Re: material hardness questions

If you're looking for a particular surface hardness, I figure a coating is probably easier to organise than an FFF material and exacting machine setup to achieve the same property.

On another note, my gut instinct is that rollers will be under cyclic loading, and an industrial environment will mean there are a lot of cycles: does anyone have any info/experience regarding the fatigue performance of FF plastic parts? My suspicion is that the variability of bonding between filaments/layers would make the fatigue performance of a printed part also highly variable, even if the raw material properties themselves looked acceptable...

SD3. Mk2b + glass, heated enclosure, GT2 belts, direct drive y shaft, linear bearings, bowden-feed E3D v5 w/ 0.9° stepper
Smoothieboard via Octoprint on RPi

7 Reply by adrian (edited by adrian 2014-01-30 03:18:05)

  • adrian
  • Member
  • Offline
  • From: Canberra, Australia
  • Registered: 2013-01-15
  • Posts: 1,623

Re: material hardness questions

grob wrote:

On another note, my gut instinct is that rollers will be under cyclic loading, and an industrial environment will mean there are a lot of cycles: does anyone have any info/experience regarding the fatigue performance of FF plastic parts? My suspicion is that the variability of bonding between filaments/layers would make the fatigue performance of a printed part also highly variable, even if the raw material properties themselves looked acceptable...

Yup - Hence my recommendations around Nylon which will alleviate most if not all of that issue - particularly the Industrial spec 645 (they've used this stuff to print bones.. and its used in various areas of medical applications as well as industrial). Its fused layers are far more like PLA than that of ABS....  and combined with its inherit flex, it should overcome those issues far better than other currently readily available filament types.

8 Reply by grob

  • grob
  • grob
  • Member
  • Offline
  • From: Sydney, Australia
  • Registered: 2014-01-02
  • Posts: 900

Re: material hardness questions

Sounds good to me. I'd love to see you experiment with this tjhering, and let us all know how you go!

SD3. Mk2b + glass, heated enclosure, GT2 belts, direct drive y shaft, linear bearings, bowden-feed E3D v5 w/ 0.9° stepper
Smoothieboard via Octoprint on RPi

9 Reply by tjhering

  • tjhering
  • Newbie
  • Offline
  • Registered: 2014-01-30
  • Posts: 5

Re: material hardness questions

I have found Somebody who used polyurethane belting as a filament and it worked well at the following link. Just google "polyurethane filament" and choose the second site.

I think I have found enough suitable materials to move forward with this idea. So now the big question is which 3d printer would work well with a flexible filament. Makergeek has me interested because of their large print size and low price. Any suggestions?