X-metal screw problems.

[WavecloudCustoms]

I’ve never actually rounded one yet though.. you can actually feel the softness if the metal through the hand tool.

I find applying a lot of downward pressure - more than torsional pressure (twisting) works.

On other situations with chewed up screw heads there are various methods.

 

[scienergy]

I use a certain drill bit to drill off the head of the screw until it pops off. Then once I have the shaft, carefully use needle nose vice grips to unscrew.

OEM screws are pure absolute garbage cheap grade stainless steel that is soft and .... I could go on. They strip VERY easily even when used w/ some of the highest quality tools in the world. They corrode in certain conditions. Because of all this I made OXM screws from a harder grade of marine stainless so they accept more torque while holding shape. Marine grade (made for boats, watercraft, etc) eliminates the corrosion problem seen with OEM screws.

 

[NoFair]

The OEM screws are fine as long as they are lubed and not over tightened. Sadly they are often dry and over tightened and galling with titanium often leads to a stuck screw. Better quality screws like above should help. Warm concentrated HCl should remove any stuck screws while leaving the titanium undamaged..

 

[zwc0442]

The tendency of the oem ones to strip isn't because of cheap stainless. 304 which is the most common and what they probably used has pretty much the same strength/hardness characteristics as 316 stainless. Stainless just isn't a great material for making a fastener. Just a plain steel 2-56 screw has around 170,000 psi of tensile strength. The same fastener made of stainless is only 70,000. Stainless steel is just plain softer so it is easier to strip. Stainless is great for corrosion resistance but much softer material.

 

[NoFair]

The tendency of the oem ones to strip isn't because of cheap stainless. 304 which is the most common and what they probably used has pretty much the same strength/hardness characteristics as 316 stainless. Stainless just isn't a great material for making a fastener. Just a plain steel 2-56 screw has around 170,000 psi of tensile strength. The same fastener made of stainless is only 70,000. Stainless steel is just plain softer so it is easier to strip. Stainless is great for corrosion resistance but much softer material.

If they weren't stainless they would have corroded badly and been stuck because of that. One of my Juliet pairs has been off shore sailing with me and anything non stainless rusts in days.

 

[zwc0442]

If they weren't stainless they would have corroded badly and been stuck because of that. One of my Juliet pairs has been off shore sailing with me and anything non stainless rusts in days.

Yep exactly. Stainless is just a soft material no matter what doesn't matter the grade is what I was getting to. So not a design problem from oem just the characteristics of the material that needed to be used for the application.

 

[THE X-MAN]

I hate machining stainless...especially tapping the small stuff.

 

[NoFair]

Yep exactly. Stainless is just a soft material no matter what doesn't matter the grade is what I was getting to. So not a design problem from oem just the characteristics of the material that needed to be used for the application.

I think there are some high nitrogen stainless with better stats, but Afaik they are expensive and not seeing much use yet.

 

[scienergy]

Some other people on the forum have mentioned the hardness thing. They tell me they are harder ... repeating what they've told me >_< *shrug*

Having seen some kind of red "rust" formed on some frames in the temple joints and sometimes in the bridge makes me wonder about the quality of the metal they were using for the screws & pins -- the optimal place to cut production / material costs if there were any.

 

[zwc0442]

The reason why stainless steel is resistant to corrosion is due to the oxide layer that forms due to the chromium content. Titanium is the same way to a certain extent its natural oxide layer protects it from corrosion. Stainless has a natural oxide layer that protects it against corrosion. But if that oxide layer is broken through then the part can corrode. After machining stainless needs to be passivated for it to be as resistant as possible. Machining and such can leave tiny bits of other material embedded in the stainless steel giving way for something to rust the part. With any of the rusted screws I've seen the part may have not been passivated and cleaned fully and that's what allowed for the screw to corrode or something broke through the natural oxide layer.