Quick Review: Pittsburgh Automatic Center Punch

The Pittsburgh Automatic Center Punch is a cheap automatic center punch found at Harbor Freight. Like other automatic center punches, you simply press the handle down on the place you'd like to punch a mark, and an internal spring loaded hammer will drive the tip into the workpiece. 

Construction

The construction of the center punch is quite solid, and the solid brass handle feels weighty in the hand. The tip is relatively sharp and made of Chrome Vanadium steel, and is more than hard enough for marking most materials. The knurling on the handle offers a good grip. The handle can unscrew into three parts, which allows the user to replace the tip or any other internal components. 

Disassembled punch

Build quality is pretty good considering the price. The entire handle was turned on a lathe based on the machining marks left over, and the threads and knurling are clean. While there's a few marks and marring on the brass handle, it's not that bad, and is nearly unnoticeable unless you look very closely. Brass is pretty soft, so it'll get marred easily anyways, even from dropping it onto concrete. I am quite curious how the handle patinates over time, given that it's brass. It should make for an interesting looking tool after a few years of use. 

Use

The center punch does its job reasonably well, making decent marks in aluminum and steel. I did run an issue two or three times where pressing down on the handle did not activate the hammer, but a simple unscrew and rescrew of the handle aligned the pieces back together. Oftentimes, I used it a few times on some of the marks to get better definition.

Marks on some scrap aluminum

Marks on steel prior to drilling. These holes were punched a few times to get better definition

I did run into an issue trying to punch harder steel. The tip wasn't hard enough, and ended up mushrooming. This is most likely due to user error, as the steel was likely way harder than I had expected it to be. The tip is replaceable, but I was unable to find any replacement tips for sale anywhere. Given that the entire punch was less than $3, it doesn't seem like it was cost effective to sell replacement tips, even though it's replaceable. Plus, Harbor Freight offers a lifetime warranty on their Pittsburgh products, so it's easy to drop by and get it exchanged, no questions asked. 

That being said, I was curious at how difficult it would be to sharpen the tip, or at least remove the mushrooming so it can still be used. I took the tip out, and clamped it onto the chucks of a drill. I then ran it against a file to smooth it out. The tip is pretty hard, so the file wasn't particularly effective at sharpening, but it managed to remove the mushroom. Now it still works, although the marks aren't as sharply defined as an original tip. Plus I'm unsure whether or not the tips are case hardened, in which case doing this would start to expose the softer metal underneath.

Tip reconditioning, wouldn't recommend it given the tool has free exchanges

Conclusion

At a normal price of $3.99, this is a pretty good deal. At a sale price of $2, picking one up is a no brainer. While it doesn't offer the same precision and craftsmanship as a better tool like a Starrett, it is adequate enough for nearly all the things a hobbyist would need a center punch for. Coupled with a lifetime warranty, it's a great value, and a worthy addition to any maker's toolbox, even as a backup.

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