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Armstrong Titanium T Nuts Torx head stainless 316L screws

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Created by Camarillo > 9 months ago, 4 Jun 2020
Camarillo
369 posts
4 Jun 2020 4:06PM
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2 questions:
Why are the screws not titanium?
Are the screws M6 or M8?

kobo
NSW, 1107 posts
4 Jun 2020 6:50PM
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The screws are stainless because they are softer than titanium and therefore they bite a little and never come loose, it's the same with the the titanium fuse , it's great as the screws never work loose or corrode.

Camarillo
369 posts
4 Jun 2020 5:02PM
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So titanium screws screwed in titanium tend to come loose?

And are the screws M6 or M8?

emmafoils
307 posts
4 Jun 2020 5:08PM
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My understanding is they tried T screws but they broke a lot.

They are M6

Camarillo
369 posts
4 Jun 2020 10:58PM
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emmafoils said..
My understanding is they tried T screws but they broke a lot.

They are M6


I thought titanium is supposed to be stronger than stainless steel?

I suppose that with M6 Armstrong is exploring the boundaries of what is strong enough.

For 2020 Naish is using a mix of titanium and stainless screws , all M6...

MidAtlanticFoil
818 posts
5 Jun 2020 1:38AM
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The other benefit, especially with the fuse being titanium, is that you can't strip the fuse. The screws threads would be ruined first.

The softer screw really allows you to crank it tight and the threads bind well with out loosening over time. If it was titanium on titanium, you wouldn't have that little bit of give, so they could come loose or strip.

Cygnify
QLD, 125 posts
5 Jun 2020 9:39AM
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It really works well as everyone is saying. I can really crank the screws tight and they never come loose in a session.

kobo
NSW, 1107 posts
5 Jun 2020 12:12PM
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I don't even do them up very tight and they still never come loose

JB
NSW, 2232 posts
Site Sponsor
5 Jun 2020 1:09PM
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I think there's possibly some confusion here. Titanium is not harder than SS316. It's actually quite soft in comparison. Generally one may steer away from Titanium as it is easy to destroy the head/tooling if you get a screw a little too tight.

The positives to Titanium is they are really easy to drill out (i.e. because they are soft), SS316 is a biatch to drill out. But mainly Titanium has amazing corrosion resistance, this is the only reason you would go with Ti over SS316.

hilly
WA, 7875 posts
5 Jun 2020 1:15PM
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JB said..
I think there's possibly some confusion here. Titanium is not harder than SS316. It's actually quite soft in comparison. Generally one may steer away from Titanium as it is easy to destroy the head/tooling if you get a screw a little too tight.

The positives to Titanium is they are really easy to drill out (i.e. because they are soft), SS316 is a biatch to drill out. But mainly Titanium has amazing corrosion resistance, this is the only reason you would go with Ti over SS316.



Not sure. Quick google reveals:

Titanium is approximately three to four times stronger than stainless steel, which means its lifespan over generations is slightly longer.

Titanium - This naturally occurring metal has the highest tensile strength to density ratio of any metal, which makes it, pound-for-pound, stronger than tungsten. It scores lower on the Mohs scale of hardness, though. Titanium alloys are strong and lightweight and are often used in the aerospace industry.

blueplanetsurf
316 posts
5 Jun 2020 1:33PM
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hilly said..


JB said..
I think there's possibly some confusion here. Titanium is not harder than SS316. It's actually quite soft in comparison. Generally one may steer away from Titanium as it is easy to destroy the head/tooling if you get a screw a little too tight.

The positives to Titanium is they are really easy to drill out (i.e. because they are soft), SS316 is a biatch to drill out. But mainly Titanium has amazing corrosion resistance, this is the only reason you would go with Ti over SS316.





Not sure. Quick google reveals:

Titanium is approximately three to four times stronger than stainless steel, which means its lifespan over generations is slightly longer.

Titanium - This naturally occurring metal has the highest tensile strength to density ratio of any metal, which makes it, pound-for-pound, stronger than tungsten. It scores lower on the Mohs scale of hardness, though. Titanium alloys are strong and lightweight and are often used in the aerospace industry.



My understanding is that Titanium is stronger at the same weight, but since it is lighter and not as dense, an M6 Titanium screw is not as strong as a (denser, heavier) M6 Stainless screw.

hilly
WA, 7875 posts
5 Jun 2020 2:53PM
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blueplanetsurf said..


hilly said..




JB said..
I think there's possibly some confusion here. Titanium is not harder than SS316. It's actually quite soft in comparison. Generally one may steer away from Titanium as it is easy to destroy the head/tooling if you get a screw a little too tight.

The positives to Titanium is they are really easy to drill out (i.e. because they are soft), SS316 is a biatch to drill out. But mainly Titanium has amazing corrosion resistance, this is the only reason you would go with Ti over SS316.







Not sure. Quick google reveals:

Titanium is approximately three to four times stronger than stainless steel, which means its lifespan over generations is slightly longer.

Titanium - This naturally occurring metal has the highest tensile strength to density ratio of any metal, which makes it, pound-for-pound, stronger than tungsten. It scores lower on the Mohs scale of hardness, though. Titanium alloys are strong and lightweight and are often used in the aerospace industry.





My understanding is that Titanium is stronger at the same weight, but since it is lighter and not as dense, an M6 Titanium screw is not as strong as a (denser, heavier) M6 Stainless screw.



Always heard SS is soft. Armie says in his video with you that they deliberately used SS to bind with the harder Ti. No fizz bro

hilly
WA, 7875 posts
5 Jun 2020 2:59PM
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4 minute mark

colas
5364 posts
5 Jun 2020 3:25PM
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Camarillo said..
Why are the screws not titanium?


I cannot answer for Amstrong, but titanium is harder than stainless steel so you run the risk of destroying the thread in the fuse by overtightening them, instead of just destroying the cheap, disposable SS screws/bolts.

Also, if you are not careful: if you screw too fast (pun half-intended) without some lube you run the risk of galling, fusing the bolt in place irremediably. Titanium and aluminium are very susceptible to galling, but not bronze.
en.wikipedia.org/wiki/Galling

blueplanetsurf
316 posts
7 Jun 2020 12:47AM
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It's a bit confusing but here is a comparison of properties of Titanium vs. Stainless Steel. Assuming both screws are the same, the titanium screw is softer than the stainless steel screw:

www.thomasnet.com/articles/metals-metal-products/steel-vs-titanium-strength-properties-and-uses/

From this link:

The modulus of elasticity, sometimes referred to as Young's modulus, is a measure of the flexibility of a material. It describes how easy it is to bend or warp a material without plastic deformation and is often a good measure of a material's overall elastic response. Titanium's elastic modulus is quite low, which suggests it flexes and deforms easily. This is partly why titanium is difficult to machine, as it gums up mills and prefers to return to its original shape. Steel, on the other hand, has a much higher elastic modulus, which allows it to be readily machined and lends it to be used in applications such as knife edges, as it will break and not bend under stress.When comparing the tensile yield strengths of titanium and steel, an interesting fact occurs; steel is by-and-large stronger than titanium. This goes against the popular misconception that titanium is stronger than most other metals and shows the utility of steel over titanium. While titanium is only on par with steel in terms of strength, it does so at half the weight, which makes it one of the strongest metals per unit mass. However, steel is the go-to material when overall strength is the concern, as some of its alloys surpass all other metals in terms of yield strengths. Designers looking solely for strength should choose steel, but designers concerned with strength per unit mass should choose titanium.Elongation at break is the measure of a test specimen's initial length divided by its length right before fracturing in a tensile test, multiplied by 100 to give a percentage. A large elongation at break suggests the material "stretches" more; in other words, it is more prone to increased ductile behavior before fracturing. Titanium is such a material, where it stretches almost half its length before fracturing. This is yet another reason why titanium is so difficult to machine, as it pulls and deforms instead of chips off. Steel comes in many varieties but generally has a low elongation at break, making it harder and more prone to brittle fracture under tension.Hardness is a comparative value that describes a material's response to scratching, etching, denting, or deformation along its surface. It is measured using indenter machines, which come in many varieties depending upon the material. For high-strength metals, the Brinell hardness test is often specified and is what is provided in Table 1. Even though the Brinell hardness of steel varies greatly with heat treatment and alloy composition, it is most of the time always harder than titanium. This is not to say that titanium deforms easily when scratched or indented; on the contrary, the titanium dioxide layer that forms on the surface is exceptionally hard and resists most penetration forces. They are both resistant materials that work great when exposed to rough environments, barring any additional chemical effects.

colas
5364 posts
7 Jun 2020 2:06PM
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Beware, it says:
"steel can fit a lot of different jobs: it can be hard, tough, strong, temperature or corrosive resistant; the trouble is that it cannot be all these things at once, without sacrificing one property over the other."

And the A4 stainless steel that you can find for bolts is VERY soft, much softer than regular steel. And softer than the titanium bolts readily available. I guess it looks more maximum corrosion resistance at the expense of strength.
I tried to use A4 stainless steel bolts while changing the lock of my gate... I used the same force as my common steel bolts... they deformed and broke like butter. And cutting A4 stainless bolts to the length of my tuttle bolt is really easy, much easier than regular bolts.

There may be steels that are both hard and salt-water resistant, but I don't know if they are readily available at a reasonable price.



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"Armstrong Titanium T Nuts Torx head stainless 316L screws" started by Camarillo