In my introductory post, I mentioned that I was having a heck of a time securing my Cold Steel Rajah III in the vise because of its thick spine and flat taper to the edge and tip. I had tried the double sided foam tape, but it didn't do such a good job. Next tried some sticky drawer liner. That helped a little ... but I was still not able to get the knife at a good 90 degree angle in the vise. I did an okay job sharpening it, but knew it would need more work. Leo (Mitchell) suggested pieces of chamois. I was thinking about that this morning as I was getting ready to work out. I was in the process of wrapping my hands with foam pre-wrap before taping them and it hit me. I have got tons of pre-wrap .... it's thin, somewhat grippy and I can multi-layer it with ease to fill in the gaps in the vise. Later in the morning, I gave it a try.



Worked like a charm. I was able to get the sharpened and polished just the way I wanted. Just one small area near the tang that's not quite right, but this will do for now.

So, I think, for now I am going to stick with this method. Foam pre-wrap is cheap. If you are not familiar with it, here's a pic:



It's only about $0.99 a roll. I get it at Title Boxing
but it may be cost prohibitive (with shipping) unless you are buying a number of rolls. You can probably find it at any good sporting goods store.

Hi Dennis,

What exactly was the issue for you? Does the Cold Steel Rajah III have a full flat grind and was it a problem to get it stable? I've had that issue with a Spyderco knife. Why didn't double sided foam tape work for you? I've tried that, but it was a pain to remove it afterwards. I had a problem with non-sticky foam tape as well, because it was more difficult to position. How did you do this?

I see you've protected your knife with blue tape. I also tape my knife in the area where it is clamped in the vise, but why did you also cover the handle with tape?

mark76 wrote:


Actually, CS says the edge is hollow ground but it looks to me to be a FFG. The spine is a very thick 1/8" and tapers quickly and smoothly down to the edge and tip. The thick spine and quick taper made it difficult to position correctly in the vise. The foam tape method would not fill in enough of the gap at the top of the vise to position it properly. I kept getting a variance of up to 1 degree (on either side) depending on how I tried to reposition it. With the draw liner, I got closer ... but finally settled on a half degree variance.



It was much easier for me with the foam pre-wrap. First I taped down the edge of the pre-wrap at the spine on each side, then sort of rolled it over a few times to fill in the gap which would be present toward the top of the vise. For this knife, I rolled it over three times. Rather than sliding the knife down into the vise, I inserted it from the side (holding down the pre-wrap as I did this). To my surprise it tightened up at a perfect 90 degrees on first try.



I did this to keep any diamond particles and steel out of the pivot area of the knife as 1) the WE is new and the stones have not been broken in and 2) I was pretty aggressive with setting the edge as I had to correct some unevenness I created on my first attempt. I think I will continue to tape up my knives like that since it is quick, doesn't interfere with the sharpening process, and keeps crud out of the liners and pivot.

Dennis a Question, or anyone else that knows:

On a FFG, like Rajah or say a Manix, what are you using to find if the knife is sitting at exactly 90 degrees to the vice.

On a table saw for example, I can use 90 angle and visually see when i tilt the till it touches, or drop an angle cube on it.

But with a FFG, we have a gradual angle built into the knife, so the angle cube on the knife would be off right? And a straight edge of a 90 wouldn't be practical either.

Are you simply adjusting until an angle cube on either side of the FFG has the same measurement?

Hope its not a dumb question, but have been wondering how to accurately know I have some bigger, thicker FFG blades perfectly centered.

You could try this:
Set the knife on its spine on the WE base, and use the angle cube to find the WE base angle. If not zero, use the zero offset. Then, put cube on side of blade so that the cube will not interfere with the knife going back onto its spine. While supporting the knife while on the WE base--it will be quite top heavy-- read the angle.
Use the cube after the blade goes into the vise to try to match the same angle. This means the spine will be parallel with the base (laterally) and the spine-to-edge line will be perpendicular, therefor straight up and down with respect to the vise. Fore/aft tilt is up to you.
I could have done it 5 times while writing this. It's not hard, but it might feel like you need three hands at first.
You could also use a rotating or pivoting protractor.
Hope this helps.

dgriff,
I think I see what you mean.
Zero out the base, balance by hand the knife on its spine, take a reading of the angle of the FFG perp to the zeroed base (reading should not be a perfect 90, a tad wider due to FFG).
Pad/chammy/clamp and try to match the same reading.
I'm assuming both sides should be the same reading.

Will do and Thank You

How dgriff explained it is pretty much how I approached the Rajah III. However, even after using the pre-wrap to fill in the voids created by the taper, I was not able to achieve a perfect right / left side matching reading. Mainly because the bevels were not exactly the same from the factory. Readings were close enough that I was able to work with it. For smaller blades (like for the Spiderco Dragonfly 2 I sharpened today), this method was not very practical. Since the bevels were pretty even, I just adjusted it in the vise with pre-wrap until I got matching readings. In my mind, that would indicate that it was perpendicular (edge -spine) to the base.

I've come to the conclusion that many blades from the factory, especially thick, like say an ESEE-6, the grind is not even on the blade body .. side to side.
I had one in particular that drove me mad and assumed that was the only explanation.

My post was done at work, so it was kind of a mental exercise. Soon as I got home, I found an easier way to get the angle. Zero the cube on the base, then lay the FFG blade down so it is flat against the base (the handle will necessarily hang off the edge). Put cube on blade and measure angle. IF the grinds are symetrical, the angle of each side is the measured angle divided by 2. My Spydie super steel was about 5.2°, so about 2.5° per side.


Yes, for smaller blades, using the cube will be a problem. However, the human eye can do some amazing things. One of them is to find the center of a circle. The other is to see motion of the smallest amount out of the corner of the eye (watching out for Mr. Sabertooth...), and seeing that lines are askew, or not parallel (your picture frame and the ceiling/wall junction).
One should be able to, if you take your time, place the knife in the vise and see the symmetry in the gaps between blade and jaw. One should be able to look from behind down the edge and see that it is or is not canted to one side.
Just my additional thoughts.

dgriff wrote:


Don
You have a keen and astute mind. You must be either a scientist/philosopher of some bent or perhaps a highly skilled machinist/technician. Whatever you do for a living you have a way of thinking with great clarity and then being able to pass on your thoughts for others to follow. Glad you are here mate!

Leo