Can I place a puncture patch over another puncture patch?
 

I have a quick question about puncture repair (I know, it's a bit more basic than the usual stuff on the board!)

I just repaired about 4 different punctures on my inner tube yesterday and got another one on the way home from work today before realising there was a nail in my outer tire :bang:

This last puncture however was over one of the previous patches that I'd placed, and I'm wondering if I can stick another patch over it to repair it. There would be a bit of overlap with the tube probably because the hole is towards the outer edge of the patch.

I could go out in the rain and pick up another inner tube, but I don't see any reason another patch wouldn't work. Just wanted to ask so I don't end up having to walk 8 km home from work again tomorrow!

It's a 26 x 1.9 mtb tire, by the way.

I'm happy to run tubes with many patches, but to date have drawn the line at patching a patch. I guess if the composition of the top surface of the patch is similar enough to the tube's surface so that the next patch adheres properly, then there's no reason it wouldn't work. If the puncture is near the edge of the first patch, there might be some concern about sealing and leaking along the edge of the first patch where it meets the tube.

As long as the new hole is not close to the edge of the old patch a new patch should close off the hole and stay together. At some point you may want to look into tires that are more puncture resistant.

Kind of depends on what patches you are using.
If you have a cheap patch kit that's akin to pasting bricks to the tube, you probably will have bad luck.
If you have something like REMA patches, (I see 10 Wheels posted a pic of REMA in post number 4) with a feathered edge, your chances of success are MUCH better.

I'd get a new tube and try patching the old. IF it works, you have a spare tube ready for emergency.

I'm using rema tip top glue with some cheap chinese patches I picked up that look just like the patches in the photo, without the feathered edge. The other patches seem to have held up pretty well though. I'm sticking a patch on anyway and I guess I'll let it dry a while and try some rigorous testing to see if it'll come loose or let air out.

Nails do make holes in tires that is true. But if you are not using one, a tougher more puncture resistant tire like a Schwalbe Marathon Plus or Continental Country Plus can reduce the frequency of flats.

I've overlapped patches with reliable success. Do it.

FWIW, I always take the time to find out what caused a flat as part of my repair procedure. Prevents this type of thing from happening, and only takes a minute.

overlapping patches is fine.
patching 4 or 5 holes on a given innertube isn't worth the effort (compared to just using a new $4 tube) unless the process of patching tubes, or the fact of reusing, really scratches your back and gives you warm fuzzies.

Haha, it was more a case of buying a patch and glue thinking I had one puncture, and then finding out I had a couple more. It's my own fault for not checking the tire for nails and such. I'll definitely be getting a spare inner tube at the earliest opportunity though.

totally makes sense. and it's worth patching each marginal hole that you find.

I have patched over patches before without issues. I do have a box of 100 Rema patches and an 8oz jar of Rema glue, so you can see why I'll continue to patch till kingdom come. My son seems to be a magnet for flats, so that was why I invested in the Rema "family" pack.

A caveat though; I'll never put a tube with more than two patches on the front wheel, as a matter of principle and self-preservation.

I have also used a patch over a patch before so no worries there. If you want to remove the first patch and just use one larger one to seal both holes you can remove it by just holding a small flame over the patch for a few seconds until it's just slightly too hot to touch and then peel it off (it will cool off in a few seconds so you can handle it). It may come off in pieces so just repeat the heating process.

A patch over a patch will work , done it many times myself .

When you have a 5sp IGH rear, the effort to pull the tube out of the mounted wheel and patch is far less than the effort to replace the tube.