Uni Nano Dia Leads

I tried different leads including Uni Nano Dia, but it didn't make any difference. I suspect it has to do with the actual tip retraction mechanism, because I tried putting a brand new lead in and using it immediately and it performed pretty well. Then I cycled the retraction a few times and tried again and it was back to breaking off under light pressure. I did a lot of my experiments on paper, but I'm primarily using this for woodworking, so I just can't have the lead breaking that easily.

I use Uni’s Nano-Dia leads in 2B (which is my personal description of the perfect lead and in use in all my mechanical pencils). I have been using all three for some time in regular rotation for note taking with my other pencils, I don’t personally notice any sponginess in writing with them. There is a slight amount of tip wobble on the Advance but it’s only slight and not an issue for me.

Probably my third favorite lead behind Pilot Neox and Pentel Ain Stein, but this opinion requires some clarification:. * Not all leads perform the same at different sizes! Uni Nano Dia excels in sizes 0.4 or *smaller*, but I much prefer both Pilot and Pentel in larger sizes.