The unlikely story of a flat tyre.

[SmoothAirCruiser]

So I had that sad experience when I walked into the hanger the other day.

A flat tyre.

Sigh.

The tyre had only just been replaced by my mechanic a few weeks (few flights) back in the annual inspection.

Fortunately in the hanger, it is less painful that in the field. So I went through the process of jacking, wheel pants, brakes, remove wheel, depressurise, split rim remove tube and then all in reverse. Basically I used the time-window I had for flying to make the repair.

But where this gets interesting is when I examined the tube I removed I placed in in water to find the ‘hole’ and the shape was odd. So I took a photo.

Driving home it bugged me…..

Then it finally dawned on me that the shape was familiar and then it really bugged me. It looked a lot like an office staple. But how? And where is it now… oh dear please don’t tell me I just ruined another very expensive leakguard tube.

Due to work/life commitments I had to leave it for a few days, but as soon as I had a chance I returned to find the tyre still inflated. Good start. But I just couldn’t risk the fact that it might still be in the tyre pressing against the new tube to surprise me another day.

So I went through the process again; jacking, wheel pants, brakes, remove wheel, depressurise, split rim remove tube. (Getting good at it now) Couldn’t see any damage. Rolled the tyre around and shined a light in. Nothing but powdered and granular talc. Tapped and fumbled with my finger, couldn’t feel anything, but also couldn’t see past my hand. (It’s a small inner diameter really) so I reached for the nearest blunt tool to brush through the talc. This happened to be a Phillips head screw driver and it happened to be MAGNETIC. Culprit found and the shape matched exactly.

So, I’ll never know why. I suspect when the type was on a shelf somewhere someone pulled apart the pages of an invoice or shipping docket or something and just by bad luck the staple fell inside the tube. Once in there it was never going to fall out or even be seen. Is there a lesson here ? Maybe, maybe it’s that remote and unlikely thins are still possible. Maybe it’s that we should all closely inspect even new parts for faults, flaws and contamination.

I am not sure what conversation to have with my mechanic yet but I need to tell him.

 

[Thierry A]

Interesting for sure, thanks for sharing... Of additional concern to me, and obviously not your issue, is the "granulated talc". It would be interesting to know what talc was used. In my experience talc does not do what I see in your picture.

 

[Mel]

Maybe I'm missing something, but if the staple didn't penetrate the tube, why did it go flat?

 

[RV7 To Go]

Interesting for sure, thanks for sharing... Of additional concern to me, and obviously not your issue, is the "granulated talc". It would be interesting to know what talc was used. In my experience talc does not do what I see in your picture.

I agree with the above. Ask your mechanic what they used. If it was baby powder it doesn't have talc any more but uses corn starch instead (I believe in Europe some still use talc). Corn starch will ball up like that with a little moisture and eventually rub through the tube to cause a leak...not your present issue but possibly down the road.

 

[Snowflake]

Maybe I'm missing something, but if the staple didn't penetrate the tube, why did it go flat?

I think he means it went flat the first time due to the staple, but the replacement tube wasn't in there long enough (or flown on) to wear a hole yet.

 

[Mel]

I think he means it went flat the first time due to the staple, but the replacement tube wasn't in there long enough (or flown on) to wear a hole yet.

Thanks. I didn't get that he had "replaced" the first tube.

 

[walkman]

I agree with the above. Ask your mechanic what they used. If it was baby powder it doesn't have talc any more but uses corn starch instead (I believe in Europe some still use talc). Corn starch will ball up like that with a little moisture and eventually rub through the tube to cause a leak...not your present issue but possibly down the road.

Looks more like Peruvian Flake to me

 

[BruceW]

That looks more like a larger packing staple, not a paper staple. Let's see, opening the shipping box of the tire or tubes and it fling inexplicably inside the tire and went unnoticed. There, mystery solved.

 

[wirejock]

Five years as a truck/passenger tire mechanic. I found all sorts of stuff both inside and sticking out of tires. Pliers, screwdrivers, etc.

 

[hgerhardt]

..........The tyre had only just been replaced by my mechanic ....................

Once again you've proven the adage that if you want the job done correctly the first time, you need to do it yourself!

 

[KeithO]

Murphy is always lurking....

 

[skylor]

This thread is a good reminder of why it's a good idea to do tire/tube changes on a "sterile" work bench. I usually clean my workbench surface then tape down a sheet of masking paper/butcher paper on the workbench before doing this type of work. Standard shop "debris" such as metal chips, particulates, etc. can be bad to have sticking to the side of a new tube or finding its way into a tire.

Skylor