I’ve got a couple of cracks in a steel frame. One comes off the bottom of the seat tube slot, the other is coming off a cut-out on the top of a top tube/head tube gusset.

I figure I can get a blob of weld on them if necessary, but I’m wondering if they’re anything to particularly worry about. Any ideas?

I wouldn’t be too concerned about the seat tube ones, looks like at some point an undersized seat post has been used and the clamp has been overtightened to compensate. Keep an eye on these, but don’t worry too much.

Can’t quite tell what we’re looking at on the second photo – it’s a weird place to have a cutout in a gusset. Any chance of a better pic?

The correct size of post has always been used, with about 200mm of it in the frame. Not sure how they appeared, but mildly concerned that they’re going to continue to spread.

The right-hand side bottom picture shows the top tube, leading into a gusset with the head tube at the top right. The crack is mid-way down the r/h side, coming off a cut-out of the manufacturer’s logo. (I don’t really want to show the full logo.)