Broken Backside in the OHR sensor?

Todd Danielczyk

@GiPFELKiND I am leaning towards material incompatibility due to multiple failures on your watch(es)…

Let me explain this a bit more; materials like acrylic are susceptible to reactions with alcohol, polycarbonate will craze when they come in contact with acetic acid (vinegar) and acetone will react with polycarbonate, acrylic, PVC. That’s why you never clean a polycarbonate window with most household glass cleaners as it will haze and get small cracks to form into larger cracks.

If I knew the exact composition of the back of the watch I could point you what may be causing this.

As there have been multiple systemic failures of the backs of your watch it is more than likely something with body chemistry and a reaction is the material. I’ve seen diabetic people that produce keotones in high amounts (have that acetone sweet smell to breath) have to switch to metal eyeglass frames as the acrylic eyeglass frames will break down along the ears, temples and nose piece. People that sweat acetic acid will have their armrest on a car door get hazy.

For me, i know to never use DEET on my gear as it will cause any of my polymer gear to soften and melt. Titanium is my preference for watch bodies so I don’t have bio-compatability issues; I can rash with some nickel and copper alloys.

TL:DR in this case it’s pointing to a you not being compatible and will more than likely keep happening. You may have to switch products to prevent the same issues repeating.

GiPFELKiND

@Todd-Danielczyk hey Todd sounds really interesting… The thing with the ketones… I had did a ketone eating time few weeks before… Could this really be the answer?

GiPFELKiND

@Todd-Danielczyk said in Broken Backside in the OHR sensor?:

@GiPFELKiND I am leaning towards material incompatibility due to multiple failures on your watch(es)…

Let me explain this a bit more; materials like acrylic are susceptible to reactions with alcohol, polycarbonate will craze when they come in contact with acetic acid (vinegar) and acetone will react with polycarbonate, acrylic, PVC. That’s why you never clean a polycarbonate window with most household glass cleaners as it will haze and get small cracks to form into larger cracks.

If I knew the exact composition of the back of the watch I could point you what may be causing this.

As there have been multiple systemic failures of the backs of your watch it is more than likely something with body chemistry and a reaction is the material. I’ve seen diabetic people that produce keotones in high amounts (have that acetone sweet smell to breath) have to switch to metal eyeglass frames as the acrylic eyeglass frames will break down along the ears, temples and nose piece. People that sweat acetic acid will have their armrest on a car door get hazy.

For me, i know to never use DEET on my gear as it will cause any of my polymer gear to soften and melt. Titanium is my preference for watch bodies so I don’t have bio-compatability issues; I can rash with some nickel and copper alloys.

TL:DR in this case it’s pointing to a you not being compatible and will more than likely keep happening. You may have to switch products to prevent the same issues repeating.

This is the first and the best answer ever!!! Not only uhhhhhh what are you doing with your watch. THANKS A LOT

Todd Danielczyk

@GiPFELKiND it can certainly affect the material.

Acetone is a byproduct of ketosis (shows up in a urine test along with ketone). The following are not compatible with acetone.

PVDF
Polycarbonate
Polysulfone
Cast Acrylic
PVC
CPVC

I can’t say for sure what the back cover material is on the Vertical is without Suunto confirming and I’m not going to offer my personal Vertical up for destructive TGA/DSC testing but from a manufacturing side more than likely Acrylic or Polycarbonate.

Either one of these will easily soften in an acetone environment and lead to the back getting scratches and stress cracks.

surfboomerang

@GiPFELKiND said in Broken Backside in the OHR sensor?:

I wear it everyday, i didnt wear it while showering, i didnt wear it on poilswimming, only make Sport with this unit.

To debunk the water issue…
I have my SV since it could be ordered. I used it in a lot of watersport sessions (salt and fresh water) and rinsed it everytime after an activity. This is how it looks now:

GiPFELKiND

@surfboomerang read the post below. There could be the answer

Todd Danielczyk

@GiPFELKiND and if it makes you feel any better, I once dissolve a vintage Montblanc Meisterstuck fountain pen into a gelatinous blob by using the wrong solution to clean it.
Alcohol and acetate don’t play nice.

I consider it a $1,200 usd lesson in chemistry!

GiPFELKiND

@Todd-Danielczyk Thank you so much

freeheeler

@GiPFELKiND
the cracks in the red circle look like they all or most of them have one starting point and it could as well be an exceeded point load and result in mechanical stress and cracks

Tieutieu

If I look to the back of my SV, it’s seems perfect (thanks to new SA activies analysis I can proudly claim that since May 16th it has recorded 296 exercices during 387 hours, 2900km, 79km elevation, and was worn H24 with sleep tracking ).
If I take time to mount my macro photo lens, zoom in zoom in again, back looks “irregular” like on @Brad_Olwin pictures.
It not eye noticable, but when highly zoom it’s not perfect…(I bet i would die if I was looking with a microscope)
But for me it looks more like small coating irregularities under the back, and very very very small surface scratches amplified by light position and zoom.

@GiPFELKiND sorry for you it happens to you again. One default watch is bad luck, two is bad coincidence, three is really suspicious.

@Todd-Danielczyk said in Broken Backside in the OHR sensor?:

vintage Montblanc Meisterstuck fountain pen

yeah my daily driver on the paper! sorry to read that!

btw this is mine after 4 months (worn 24/7, housework, sawing wood, running on trails, sea kayaking, lots of keyboarding ). Not a single scratch!

@westie Same here… I have just checked my SV, there’s literally no scratch on the sensor. I guess I am not training enough