red house

Over the past few days I have noticed a distinct and somewhat disturbing link between the use of a black sharpie marker to mark the locations of the punctures on my "spare" tubes (btw, "spare" tubes = tubes I've got laying around that were left unpatched from previous flats) - and the incidence of patch failures. So far the only tube that I've been able to patch successfully was a tube with a massive gaping hole that required no sharpie to locate upon discovery (i.e. it was easily visible to the naked eye without even needing to inflate the tube). On another tube, I marked the area where three small closely grouped punctures were located - and I patched them with three overlapping patches - which suddenly blew up upon being re-inflated inside the tire. My third spare tube has one small puncture - which I also marked with a black sharpie (for E-Z indentification), and it also didn't take well... I'm about to attempt a re-patch on that one, hopefully with better luck.



Anyways... anyone else notice a similar correlation between patch failure and the use of sharpie ink to keep track of the puncture?

RoadRanger

The alcohol wipe you should be using to clean the patch area should be taking the ink off anyways?

milnerpt

I am interested in what you find out as I was thinking the other day "damn, isnt there something to mark so I can see the puncture better?"

And I dont use alcohol, just sandpaper to scuff. Im thinking basically any material between the patch, glue, and tube will alter the bonding.... anyone have and alternative to mark holes?

Tabor

You can draw a nice big circle around where you want the patch.

red house

al-cohol wipe?

red house

a-round the hole? -?

red house

the 2nd patch seems to be a success ppl. .. (after sanding off any residual sharpie ink from the first one).




** tho, still needs to be re-inserted and inflated. (pls pray for me).

dsm iv tr

I haven't noticed that per se, but i think Sharpie ink is a permanent, solvent-based ink.

Solvent that could either thin out the cement, or cause it not to work at all.

Cheers.

FlatTop

Instead of marking the puncture, I just leave the pump attached during the patching operation. The big hole peeing air is hard to miss.

RoadRanger

I don't ever remember having a problem keping track of the hole once I found it - but never had a thorn or glass puncture. I guess if I needed to I'd stick something in the hole until I cleaned and roughed it up?

Camilo

I use a type of grease pen used for marking tires. I simply put a horizontal line on each side of the hole so that I know that the hole is right in the middle, right on the line. I space the little marks large enough so they don't impinge on the patch.

cascade168

I can't say about removing the ink, but I have found that alcohol wipes will drastically improve the likelihood of a successful patch. Especially for glueless patches. Clean, sand, and apply your patch. I like to talc my tubes and the talc is a real patch killer. So, the wipes take good care of that. Any kind of grease or oil is also going to kill a patch. The area around the puncture needs to be clean and rough.

red house

update.. 2nd patch attempt (for the tube with nail sized "massively visible" leak) required a second patch, and is now requiring a third. A third patch ppl. I only have two left. Now I will have one. God... why have you forsaken.



Three spare tubes... one success, one failure... now only one left. (and it's the last/only hope).. it must work.

dobber

Did you ever consider the fact that the patches might be the source of your troubles?

markjenn

Tangentially, I lately have been surprised at how poorly patches have been holding after repairs. I use vulcanizing cement, the "quality" black patches with red saw-tooth outlines, rough up the area thoroughly, let the cement dry, lay the patch down carefully, and smooth it out from the center out. I'm doing what I've always done, but the patches aren't sticking very well. I wonder if tubes these days have some kind of mold release compound or something on them which inhibits the adhesion of the patch.

- Mark

red house

I am officially bitter at the Universe.

waldowales

Use a commercial patch prep, like Magic Buff, and forget the sandpaper. Draw a pair of lines at 90 degree angle far enough from the hole that they don't get wiped off, so that the ends would intersect at the hole if extended. Sandpaper tend sto smear whatever contaminant is on the tube all over the patch area, where the prep liquids will remove it and leave the tube ready for the cement. I wouldn't trust the glueless patches.