Hi,

I just finished building up a singlespeed MTB that is going to be my winter beater (i know, winter is still a bit a way).

The bike is a cheap-ish raleigh that was abandoned by my old roommate. The dropouts were really really shallow (maybe only an inch deep), typical of a mountain bike. Now, me not wanting to spend any money on this project (or as little as possible), I wanted to skip stuff like using a chain tensioner.

The problem is, the way I got the chain, the rear axle sits very far out almost to the edge of the dropout (see attachment, green circle is the axle). (note, my dropouts do not look like this, it is merely to demonstrate the placement of the axle)

Is it safe to leave it like this?

It seems secure right now and i plan on replacing the QR skewer with wheel nuts.

Is there anything I could do to make it more secure? I know half chainlinks exists, but even despite this, there is only maybe half and inch at most left in the dropout. I'm not opposed to DIYing some sort of contraption either if anyone has any ideas.

Not a problem at all. I've had less in the dropout before.
The half link will work with 1/2 inch of dropout.

a half link would place the axle more squarely in the drop out, but I've ridden near the edge of the dropout without issue. what's wrong with just keeping the qr?

There is a myth that a qr wont hold up under fixed gear backpedaling/skidding. A quality qr will hold fine. Never had mine slip.

If its a good QR it will hold just fine, but their are lots of cheap crappy aluminum ones out there that wont hold over time, especially from the abuse of a winter bike.

The QR is just the stock one that came with the bike. The only signifier is it says "KK" on it, which I assume is just a large japanese company that makes generic parts or something.

Anyways, thanks for everyone's help, I certainly feel more reassurance about my bike now.

You should be fine in the dropout like that, just make sure you're using an enclosed cam QR skewer. Read this if you don't know the difference: https://www.sheldonbrown.com/skewers.html

I used to have a mountain bike with exposed cam skewers and both my wheels came loose after going off some jumps. Luckily it didn't cause a crash. Needless to say I'll never ride them again, especially on a mountain bike.