Rubber Casing on GNSS Buttons

[Locus]

Evening,

Keeping it short for now. Comments / Opinions?

Usage : Non military. Appx four months in hot, dry, often sandy conditions. Appx 26-36 C







Very pleased with this unit overall, my first GNSS, used 9 times out of 10 for Grid Reference / Waypointing.

But I feel the On / Off button is becoming a cause for concern now (waterproofing / potential future button failure)

On this unit, the operational buttons come with existing minor indentations when supplied.

The On / Off button also has about half the profile of the other buttons, when supplied.

[captain paranoia]

That does look pretty poor.  Were you using any skin products at the time?  Sun block, DEET, etc?

[Locus]

That does look pretty poor.  Were you using any skin products at the time?  Sun block, DEET, etc?

Yes to Sunscreen.

Initially my opening post was going to ponder if I had particularly acidic sweat or something ( ), but I hadn't even considered the use of Sunscreen which may (or not) have contributed to wear on the rubber, as it was applied every day-  several times during the day. Wear on the rubber seems to looks far worse when photographed in macro for this post and today I was out with the unit again without issues, but the On/Off button seems like it could be a cause for some concern (potentially sticking in future) as it has worn quite low now and at an angle. From using high percentage DEET years ago (nowadays the highest I ever use is 15%-20% mixed with other ingredients), and finding how a leak of it completely fused into another item in a pack, that I can understand, but I wasn't aware of sunscreen having corrosive effect.

Following your suggestion, some googling of word combinations based on that dredged up a post on a Garmin forum from two years ago about wear on a Garmin product which others posters suggested may have been caused by Sunscreen oils attacking the rubber, but to view the attached photo one has to be registered. If it proves to be Sunscreen doing this, whenever on longer hikes in places where sunscreen is important and the GNSS is also going to be in use this is a bit problematic, apart from use of gloves or perhaps application of a thin film over parts of the unit to protect the button area. Cheers for the input, captain paranoia.

[boogyman]

This post is slightly off-topic. Related to "wear on a Garmin product" as well, but not caused by sunscreen. The lesson learned might be useful though.

I used a Garmin eTrex HCx for years. One of the known weak points of that unit is the rubber band that covers the complete side of the unit. After having used it several times in bright sunlight, the glue which should keep the rubber band in place, became liquid. As an obvious consequence, the rubber band did not stay "in place", and it became very difficult to use the buttons (because the buttons are in fact operated by small bumps located on the rubber band).

After a few Google sessions, it became clear that this was a very frequent problem with the eTrex H family of units. Several owners who had sent their unit to Garmin for reparation (long waiting times, not cheap either), complained that the repaired units had exactly the same weakness!

So I carefully removed the rubber band myself, cleaned the semi-liquid glue from the unit, and repaired it by using a thin layer of Tec7. If you have ever used Tec7, you will not be surprised that the rubber band never loosened again. BUT... that layer of Tec7, however thin it was, clearly disturbed the GNSS signal reception of the unit. It's original "location accuracy" was gone, and it never came back 

[Locus]

....BUT... that layer of Tec7, however thin it was, clearly disturbed the GNSS signal reception of the unit. It's original "location accuracy" was gone, and it never came back 

Interesting story, Boogyman. What do you guess contributed to disturbance of the unit? Attempting to repair the unit? Or something within the ingredients of Tec7?

[Lost Soul]

Looking at the pictures on the original post.  The buttons have aligned lateral cuts in them.  Just a thought, but has the damage been aggravated by sharp finger nails?

[boogyman]

Interesting story, Boogyman. What do you guess contributed to disturbance of the unit? Attempting to repair the unit? Or something within the ingredients of Tec7?

I am convinced it is the layer of hardened Tec7 that causes the disturbance. I believe that the attempt to repair the unit could not have disturbed anything.

[Locus]

Looking at the pictures on the original post.  The buttons have aligned lateral cuts in them.  Just a thought, but has the damage been aggravated by sharp finger nails?

My finger nails are always kept short, but iIt is possible that perhaps I was coming at the buttons from too much of a nail angle without being fully aware of it, due to the existing indentations being a guide. Or, perhaps during continous heat the rubber softens somewhat and any use of nail contributed to deepening of the indentations. One of the buttons (3rd photo, 2nd button from the left) has a deep indentation in it now, which doesn't seem at risk of splitting in half but is not in the best condition anymore. It is that one and the on/off button which are in a sorry state.

I am convinced it is the layer of hardened Tec7 that causes the disturbance.

I don't know the 'how' of that, but I did wonder about it a while back when looking at a specific size cordura covers that could be purchased for my particular unit. I wondered if the signal was at all affected by covering the unit. Maybe other users have the answers to that one.