I posted this on FF, and am posting it here too for the sake of being thorough. I can't imagine more than a handful of people would ever need this information, but here it is anyways.
I made two maps, one of the Greater Sakai area with a detail of the area around Ashi Hamono, and one of the 'Knife District'. Everything in the Knife District map is more or less walkable, depending on your energy level. For reference, the distance between #1 and #8 is almost exactly one mile.
Also, to help make sense of things and put these maps in a greater context, here's a link to an excellent map of the entire Kansai area railway system - http://japanize.jp/center_base_1.pdf
- all the stations in Sakai are on grid J-9 on the second page.
The Nankai train lines are the most direct way into Sakai. If you're coming from KIX airport, you'll take the Nankai-Honsen (Nankai main line) to #1. If you're coming from Osaka, you'll start at the Nankai-Namba station (which is above ground, nearby but separate from the regular Namba station). Here you have two choices, the same Nankai-Honsen to #1 or the Nankai-Koya to #8.
There's also a JR station (Sakai-shi station) further east off the map, which you might want to use if you have a JR rail pass, but you'll have to take a taxi to get into the knife district. Ask to be taken to Sakai Hamono Dento Sangyo Kaikan, which is the only place they're likely to know, and they should drop you off at #2, the knife museum.
#3 and #6 are stops on a small antique tram line, running on tracks in the street. It's very slooooow and more of a quaint tourist line than a commuter line. It might be useful if you're tired of walking, but it's not going to save you any time. Be prepared to wait 20 minutes for a train to come by.
I haven't been to Ashi-Hamono (#B), so I hesitate to recommend anyone else to visit their shop. However, they are a major OEM and I imagine there's some interest in tracking them down in the hopes of getting major brand stuff at a discount. So I did a little research and Google Street View shows what looks to be a knife shop at Ashi-Hamono's address.
It's on the same train lines you would be taking into the main knife district of Sakai. #A is the next station north from Sakai station (#1 other map), on the Nankai-Honten line. #C is a tram-stop four stops north from #3 on the other map. Further our east in greater Sakai, #D is the next stop north from Sakai-Higashi station (#8 other map), and #E is the JR station I mentioned above, if for some reason you'd like to stick with JR trains.
To make things confusing, because that's what the Japanese are best at, each shop has a different name than the brand they sell (with the exception of Ashi-Hamono). If you ask someone where Suisin is, even if they understand English, they might not know, because their store is actually called "Knife System"... makes sense, right?
Konosuke's store is called Kaneshige Hamono, and Tadatsuna's is Nagata Hamono, but at least they have a banner out front that says 'Ikkanshi Tadatsuna'. There's not really any reason for you to worry about this as long as you stick with the map, but it's crucial if for some reason you need to ask directions.
And for reference, here's a list of the knife brands/stores and their addresses in kanji, should you need it.
Konosuke (幸之祐) - sold by Kaneshige Hamono (カネシゲ刃物)
Suisin (酔心) - sold by Knife System (ナイフシステム)
Tadatsuna (忠綱) - sold by Nagata Hamono (永田刃物)
Knife Museum, officially called 'Sakai Hamono Dento Sangyo Kaikan' (堺伝統産業会館)
Ashi Hamono (芦刃物)
Here's more specific info on each shop, and pictures to give you a better idea of what to look for on the street. Also, open times and holidays.
Suisin - 072-232-7858
Doesn't say on their website, but I'm fairly certain they were closed on mondays... but don't take my word for it.
Suisin has a very small store, it's more like a business office that happens to have a display case. No one spoke english when I was there, but they were happy to let me handle whatever I wanted.
Tadatsuna - 072-232-2921 / 072-232-1132
Also doesn't say, but I think they're either closed sunday or monday, can't remember, sorry. It'd be a good idea to have someone at your hotel call them in advance.
This is a proper shop, but again, no one spoke english. Don't let that discourage you though, pointing and nodding will usually get the job done.
Konosuke - 072-222-0081
Says they're open 7 days a week, from 9-6
This is how the store looked almost a year ago when I went. However, they were renovating the area next door, on the ground floor of the same building, so it might look different now. At the time, they didn't have any knives on display, but Kawamura-san spoke excellent english, and would bring out whatever I wanted to see. It was mostly blank blades without handles. After picking out the blade, I picked out the handle separately, and they hammed it together in the shop.
This is probably outdated information by now. He told me they would have a proper display area when they finished their renovation.
Ashi Hamono - 072-229-4920
Assuming their 'reception desk' is the same as their shop, they should be open 9-5 with an hour break for lunch, closed sundays & holidays.
Here's what it should look like, according to Google Street View. You can see what appears to be a wa-handle in the display window at the left and 3 knife blades in the sliding door window.
Knife Museum - 072-227-1001
Open 10-5, closed on tuesdays
This is a pretty big place, with a replica forge and a sequence of knives showing progress through the forging process. They also have a display of every kind of traditional knife imaginable - check out the 400mm deba in the center on the back wall (3rd photo). And that's only half of the place. The other half is a shop selling Takayuki knives and a whole bunch of OEM brands I had never heard of before (4th photo). There was a huge variety, with lots of fancy stuff like damascus and etched blades.