FrankTalk.org

I've been injecting for five years, and have gotten pretty good at it, so the other day when I could not get the needle through the tunica (corpus cavernosum covering), I thought, "Uh-oh, scarring." I tried another spot - same thing; then got it into a third spot and had a good injection. Later that day I got out a 30-power microscope and looked at the needle. It looked like I expected - it had been ground at about a 20-degree angle to give a sharp wedge. Then I looked at a used needle and saw that it had been ground two additional times, at 90 degrees left and right of the first grind, giving a visibly sharper point. More used needles were the same. So the problem needle had come off the assembly line lacking two grinds. These are BD insulin syringes, 31 gauge needles.

Looking back on my spreadsheets, it seems that maybe 3-5% of my needles were singly ground.

I'm going to put future syringes under the microscope before filling them. FT friends dating with Trimix might want to do this before pre-filling; you don't want to get stuck with a single-grind needle in a men's room or date's bathroom under time pressure.

30X and 40X lighted loupes are quite cheap on Amazon, under $20.

Very interesting, but not totally surprising.
Since I'm a newbie I don't know a lot about needles other than length and gauge.
I might have to check out some tips with magnification as you suggest. I guess some people have brand loyalty as well, but I just look for the ones with good ratings on Amazon. A box of 100 is gonna last me a year or more.

Dull ones certainly hurt. I accidentally tried to put the wrong end of the cap on a syringe after filling it once time (just touched it lightly really). I went ahead and used it for the injection... Big mistake... ouch! And it did not pierce the CC, thus was a failure. Lesson learned. [And as someone mentioned in another thread... I also contaminated the needle when I touched the cap with it ].

I'm surprised. I thought BD was supposed to be the better brand, although it's not the one I use. They have too much plunger resistance for my tastes. I like the Easy Touch brand, although I've never examined their needles tips under magnification.

UPDATE FROM O.P.
Upon examining another needle under 40X, I found a long curly chip like you get when machining a rod on a lathe, attached to the needle about halfway down. It was very thin, maybe a fiftieth of the needle diameter, and broke off easily, leaving a tiny tang on the needle. The chip was so fragile, I guess it would have broken off at the skin surface had I injected with this needle, but the tang would have cut a little groove in tissue.

I advise all injectors to get a lighted loupe. The light will cause bright reflections from flaws as you rotate the syringe.

I wonder if you got a bad batch. I think I'd call them with the batch number and see what they have to say. They may need to do a recall.

Makes sense.
I normally go to the fridge.
Draw up trimix,
Put the orange cap back on.
Go to the bathroom to inject.

A couple of times I had trouble inserting it into the corpus cavernosum.
I never checked but this explanation would likely be why.

More than once I thought of injecting right there in the kitchen.
But the thought of four women in the house catching a glimpse of sticking a needle in my dick would likely terrify them.