Spyderco Forums

Ultem is a great material and looks amazing as well. I'd love to see a run of Seki models in Ultem with something like Cruwear. Yes, I know there are aftermarket options but I like factory direct stuff!

You'd probably do better asking for ones made in Golden.

Obligatory Ultem photos.

The material may be great, but that color…. Looks like dehydration to me… are there other brighter options?

Jesla wrote: ↑

Mon Mar 18, 2024 1:49 pm

The material may be great, but that color…. Looks like dehydration to me… are there other brighter options?

Dehydration Amber and black are the standard and most common colors but Ultem (Polyetherimide) is available in other colors as well. (White, Grey, red, blue, green)

Mushroom wrote: ↑

Mon Mar 18, 2024 3:49 pm

Jesla wrote: ↑

Mon Mar 18, 2024 1:49 pm

The material may be great, but that color…. Looks like dehydration to me… are there other brighter options?

Dehydration Amber and black are the standard and most common colors but Ultem (Polyetherimide) is available in other colors as well. (White, Grey, red, blue, green)

…

Why this plastic instead of FRN?

OK Steelcity,

You got my attention. Can you give some information as to where I can find out more information, and get some of the stuff to test?

sal
___________________________________________________________________________________

"Continual improvement is our evolutionary obligation to humankind".

I’d much rather have FRN. Other than being translucent, Ultem is an inferior material in every way.

kennethsime wrote: ↑

Mon Mar 18, 2024 11:24 pm

I’d much rather have FRN. Other than being translucent, Ultem is an inferior material in every way.

I haven´t really looked into Ultem, so I am not in a position to talk about or compare it.

Just saying that also if Spyderco wanted to go translucent, they´d have their FRCP for that... (don´t know though if they could or would do FRCP in Seki knives).

Jesla wrote: ↑

Mon Mar 18, 2024 1:49 pm

The material may be great, but that color…. Looks like dehydration to me… are there other brighter options?

Beat me to it. I was gonna be a smart-alec and say Ultem reminds me to drink more water.

I though that the hype of this pee-through material has waned already.

sal wrote: ↑

Mon Mar 18, 2024 11:18 pm

OK Steelcity,

You got my attention. Can you give some information as to where I can find out more information, and get some of the stuff to test?

sal
___________________________________________________________________________________

"Continual improvement is our evolutionary obligation to humankind".

It’s a common material. You can find it all over but here’s a McMaster Carr link.

https://www.mcmaster.com/products/ultem-sheets/

Really do not get the hype. Besides the color joke that surrounds the material it looks like some kind of 50+ year old plastic out of my grandparents house. Nothing to call atractive in my eyes.

How does Ultem respond to RIT dye?
Ultem can be good to see if you are developing rust under scales.
I would like to see Ultem used on the Roadie. I would call it the Roadie “Apple Juice”

Everytime I see ultem.

zhyla wrote: ↑

Tue Mar 19, 2024 3:50 am

sal wrote: ↑

Mon Mar 18, 2024 11:18 pm

OK Steelcity,

You got my attention. Can you give some information as to where I can find out more information, and get some of the stuff to test?

sal
___________________________________________________________________________________

"Continual improvement is our evolutionary obligation to humankind".

It’s a common material. You can find it all over but here’s a McMaster Carr link.

https://www.mcmaster.com/products/ultem-sheets/

And they are an authorized Spyderco dealer. I bought some from them, 2yrs ago, and it was the Mitsubishi Chemical Duratron U1000 PEI.


@sal I would think one or more of your plastics materials suppliers would have it. Possibly even give you samples? A lot of places that have Micarta or FRN sell Ultem 1000 as well

Matus wrote: ↑

Tue Mar 19, 2024 2:41 am

I though that the hype of this pee-through material has waned already.

The material is making its rounds in other industries now as well, such as fashion. (Watches, sunglasses, jewelry, etc.)

I don’t think it will go away completely but it will probably be trendy for a little while longer before something else comes along to take the attention away.

Why is everyone going mad for this p*ss coloured plastic for knife handles?

I’d much rather have G10 scaled Seki’s.

dang, not much love for ultem in this group! i think it looks great personally. i love the color. i mean look at these knives!?!

sal wrote: ↑

Mon Mar 18, 2024 11:18 pm

OK Steelcity,

You got my attention. Can you give some information as to where I can find out more information, and get some of the stuff to test?

sal
___________________________________________________________________________________

"Continual improvement is our evolutionary obligation to humankind".

Thanks for the reply Sal. As you can see, it definitely has its fans and its haters. But then again, so does FRN, and I may be FRN's #1 fan!

"Ultem is a transparent amber colored high performance polymer material with high strength, rigidity, dimensional stability, heat and chemical resistance properties."

As far as where to get, zhyla mentioned McMaster, and here is a link to Maker Material Supply,

https://www.makermaterialsupply.com/col ... mber-color




An Introduction to ULTEM Plastics:

High-performance plastic polymers fall into two categories: thermosets and thermoplastics. Thermosetting polymers are those that solidify to an irreversible hardness after curing due to chemical bonds within the plastic. The polymer hardens in a cross-link pattern that prevents it from re-melting, even under extreme heat.

ULTEM®, the branded name for polyetherimide (PEI), is one of the few commercially available amorphous thermoplastic resins that retains its mechanical integrity at high temperatures. Initially developed by General Electric Plastics Division (now SABIC) in the early 1980s, ULTEM is a high-performance plastic that has been a staple of the manufacturing industry for over 35 years. This material is strong, chemical- and flame-resistant, easy to use, and able to withstand extremely high temperatures while retaining a set of stable electrical properties.

Often used in the production of circuit boards, eyeglasses, food preparation and sterilization equipment, and, perhaps most notably, aircraft parts, ULTEM is known for its strength and durability. Read on to find out everything you need to know about ULTEM.

Mechanical Specifications

ULTEM stands out from other high-performance polymers because it is uniquely designed to remain mechanically stable under extreme conditions. It can withstand temperatures upwards of 217°C for extended periods of time and remain dimensionally stable in fluctuating temperatures. It is inherently flame resistant and produces minimal smoke that is no more toxic than smoke produced from burning wood.

Amorphous thermoplastics have the tendency to crack when they come into contact with fats and oils from food, alcohols, acids, fluids used for servicing cars and aircrafts, and other aqueous solutions. Not only can ULTEM resist stress cracking under such conditions, but it is also resistant to ultraviolet rays and gamma radiation.

ULTEM’s key mechanical specifications include:

Tensile Strength at Break (73°F): 15,200 psi
Flexural Strength (73°F): 22,000 psi
Elongation at Break (73°F): 60%
Shear Strength: 15,000 psi
Melting Point: 426°F
Flammability: V-0
Dielectric Strength in Air: 830 V/mil
These mechanical specifications are applicable only for standard ULTEM — specifications will vary for different varieties of the product, including ULTEM 10%, 20%, and 30% Glass Reinforced.


https://sybridge.com/everything-ultem/