This is great for sharpening the inner edges of my hole punches but mine all have rounded tapered outer edges and unfortunately these punches only work on the outer edges of straight-taper outer edges.
Luckily for my all I really need are the inner edges sharpened.
This is a great tool, one of those "I neve knew I needed this until I saw it" items!

I did not get the original shipment, and there was some delay in getting the product. Once they finally responded, the shipment was quick, and the agent was very helpful and responsive. The sharpener looks exactly as described and should function well. Despite the delay, I think it's a 5 star product and company

I put the Jupiter Punch Sharpener to the test the moment it arrived, and I have to say I was genuinely impressed.
I mounted a set of inexpensive punches I had purchased from Amazon in my drill press and used the Jupiter Sharpener to reshape the cutting edges. Since the quality of the steel on these punches was questionable, I wasn't expecting miracles. To my surprise, the Jupiter not only restored the shape of the punches but left them incredibly sharp. After a quick final honing, they were cutting through leather like butter. This answered a question I'd always had: Can you turn a cheap leather punch into a truly useful tool? The answer is yes—with the Jupiter Punch Sharpener.

For anyone who works with leather and wants to get the most out of their punches, I can confidently say this sharpener is well worth the investment.

Outstanding product—great job!

I love this. It makes my punches sharp quickly.

I bought this sharpener for obvious reasons, about the only tool out there that should sharpen my punches for leather work. I am not an expert on how this tool was made, but this appears to have diamonds infused into the sharpener. This is a great feature as it will do just that, sharpen the tool, and thus far it has done so. For the smaller tipped punches I am only using the end and my only concern about this tool, this is where the majority of my sharpening will be happening and wonder if it will stand up the use. I found the price a bit high and but do have concerns on how long that end tip will last. I gave it a 4 based on that unknown question and price is high for what I am getting. Time will tell the true story if this is worth the money or if it is a bust. After a few uses it is showing some signs of wear. Overall, I am happy with the purchase and it does do a good job.