What's new

Testing a Kai blade in my milder razors.

The Kai blade is a little bit wider than most DE blades. Many believe using a Kai will make your razor more aggressive or efficient. I thought I would experiment using the Kai in three of my mild razors.
What I want to see is if I get a BBS shave with the Kai. I am almost certain I can get a DFS shave with a Kai.
The GSB blade is the blade I use most and is what I will be comparing to in this exercise.

1. The post war Tech.
This razor is too mild for me when I use a GSB blade. It is really difficult to get a BBS with a GSB blade. I can whip that razor around my face with little fear of cuts or weepers. I can feel the blade much more using the Kai. This will bite if I’m not careful, I definitely have to pay more attention shaving with the Kai. Still, I found a BBS shave elusive. Around the jawline there is still some stubble. A DFS is all I could achieve with the Kai.

2. RazoRock SLOC
This is a mild razor for me just like the post war Tech I can whip this one around my face with not much fear of damage to my face. When I put a Kai in the SLOC in it transformed into something entirely different. I really had to pay attention and riding the cap was needed. There was a lot of blade feel. With a three pass shave and a little touch up I achieved a BBS shave.

3. Edwin Jagger DE89
This was my first DE razor. I used it for a year before buying another DE Razor. I consider this razor a little more than mild. Maybe a medium or medium mild. This razor never shaved my neck well. I put a Kai in and took it for a spin. This razor felt like an old hat. The Kai blade didn’t seem to make it any more aggressive. Hold on around the mouth the blade starting catching skin I needed to be more careful. I thought I might have cut myself but I was lucky no blood. I would say the efficiency was improved. This might be a better combination for me. The verdict is BBS and a near BBS. on the neck.

The Kai blade will change your razors into a more efficient or aggressive razor. Of the three razors I tried the Kai in it improved the Edwin Jagger the most. The SLOC gave me a BBS with the Kai. However, I thought it had too much blades feel. The post war tech was more efficient but I still struggles to get a BBS finish.
I like the Kai in my Rex Envoy which some feel is a slightly aggessive razor. The Kai seems to have a little more blade feel than other blades i've used, but I haven't had any problems with them.
I much prefer the Kai to a Feather. To me they are just as sharp, smoother, and defintely last longer.
I've never used Kai blades but I ordered a Fatip razor from Pasteur yesterday and ordered a tuck as well.
I've always been curious because I read about them being wider. Instead of using in anything mild, I actually want to try them in my aggressive razors to see the results. I've only got 2 mild razors left since my preference are the aggressive ones. But those wont get tested with the Kai's!
Great review of the Kai blade @Slock in your milder razors and I found the Kai SS blade sharp & smooth with excellent longevity but it is a pricey blade & I get 10 great shaves per blade as compared to 5 for other well known blades when averaging. The steel they use is a little higher quality must be I'm guessing.

I found for myself that the Kai blade is just a nice addition to my other blades compliment I enjoy, they work well in some of my other mild razors and I have started to use my milder razors more because of the extra blade feel(blade exposure). The blade is approximately 9/1000 of a inch wider or .0045 inch per side. But when you consider the arc of the blade as it is being conformed to MFG angle machined in head you lose some length so you do not get the full width per side when tensioned.
This simple great blade beats shimming a razor hands down and so when tightened in razor head you gain approximately 2-3/1000(guessing) of a inch because of arc of blade which makes a great shave on a neutral or mild razor (Gillette TTO super speeds).
I think as a persons technique is fine tuned over the years blade feel(blade exposure) is much better handled and enjoyed to work the face or head in those tough area of the beard I have noticed.
YY KAI SS DE Blade Kai .871inch wide Astra SP .862 wide-2.jpg
Have some great shaves!
Last edited:
I have some Kai blades on the way... they will be here tomorrow.. for my Flat Bottom Tech which is scheduled to be delivered Saturday.
Now that sounds like an efficient combination! I was thinking more along trying a Kai one of my Super Speeds, or maybe my Slim on #4, as that is where it is most comfortable, but lacking in efficiency.

Now that sounds like an efficient combination! I was thinking more along trying a Kai one of my Super Speeds, or maybe my Slim on #4, as that is where it is most comfortable, but lacking in efficiency.

There is aninteresting idea. I am going to try Kia in my slim. I like my slim set at 6 or 7 with a GSB.
There is an interesting idea. I am going to try Kia in my slim. I like my slim set at 6 or 7 with a GSB.

Slim on (9) and a Kai is my favourite Monday morning combination. I don't shave on Sundays, so I have more stubble, and I love the additional blade feel of the Kai and how effective it is at delivering a smooth, comfortable and ridiculously close shave.
One way of knowing the blade is wider, use your normal known blade you use a lot on one side of face and just slip the Kia in and shave the other side you will notice a difference at first until you start automatically compensating for more blade feel I have done years ago while testing the Blade. (this hobby has so many unknowns and enjoyment finding things out for yourself it keeps it interesting).
Also when the Spent Kai blade is ready to be tossed in the bin you could measure it with a Vernier or micrometer it will at least read 6-8/1000 larger than a spent regular blade because of wear on the edge. I was going measure a new blade but why ruin a expensive blade when other fellows have measured a new one.
Last edited:
I’m still a bit confused….. I’ll know soon but is a Kai blade wider or longer?

More blade reveal or closer to the end cap?
I've used Kai blades for a number of years in my Timeless razor using a .95 blade gap. Very sharp, smooth, and efficient. Fair warning: pay attention to technique, go slow, and don't press.
Last edited:
so about 1.5X the average human head hair. It will be interesting to see what the difference in efficiency is. I won't start with them since this is my first venture into DE shaving.
Like mentioned in post #5 you do not get the full .0045 of inch per side because the razor blade is bent in a arc so you will lose some width, the extra width is nothing over the top to worry about IMO. The Kai blade is just a good solid performer and hopefully you enjoy it in your milder razors or just love blade feel like a lot of seasoned shavers do. We had one fellow who wanted the most aggressive DE razor ever made and spent lots of time and $ pursuing that goal.
Top Bottom