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I bought a vintage blade on ebay with some small chips. It took me a while to get most of the chips out using my low grit DMT coarse stone. I then moved to 1200 grit Bester, King 4k, Naniwa 8k, and Naniwa 12k.
I seems like the chips go away but the blade is not sharp enough. I keep honing trying to get it sharper. It eventually then chips again before it becomes sharp enough to shave. The parts of the blade that don't have chips are shave ready.
As to the chips, what stone causes the chips? If it's on the 1200, then use the 4K to reset the bevel. I've never used a 4K King but if it's anything like the King 1K it will be a slow stone and will benefit from a good slurry to speed it a little. Some blades just don't seem to like low grit ceramics so perhaps that is the problem.
As to sharp, remember that sharp comes from the bevel while the rest of the progression is smoothing, refining, polishing. In a very real sense it will be as sharp as it's ever going to be coming off the 1K or whatever we use to set the bevel. We can use any stone for this purpose but prefer a coarser stone in order to get the job done more quickly. There's no point in continuing the progression if the blade isn't shaving sharp off the bevel setter.
Oh, the above assumes that it's not one of the blades on the no-no list that just won't take a good edge.
rs,
Tack
Find a honing mentor and visit with them, if you are in the NE Texas/SE Oklahoma area please PM me. If not, where are you from?
I have not used a 1200 Bester or King 4000 stone, could be something there. What is the brand of the razor? Has it been buffed with a high speed buffer?
What I would do is dull the blade on the side of a hone. Then reset bevel and check for chipping. The dmt I wouldnt use for this blade.
Are they chips or is there deep pitting in the blade. Pictures would help.
I will take some photos and post tomorrow
Did you breadknife or hone on the diamond plate?
If you honed on a low grit DMT to meeting bevels, you will have heavy deep stria on the bevel. That deep stria will cause a chipping edge down the road. You will have to remove enough steel to get to fresh steel without the deep stria, keep honing on the 1K.
If you hone on a 325 diamond plate after breadknifing, do not hone so the bevels meet. Leave a thin bit of steel on the edge, then complete the bevel set on the 1K. This will ensure you remove enough steel to get a good strong edge.
As said it could be the blade was damaged by excessive heat during buffing or other problems like rusting and pitting.
I am planning on trying to fix this today. Should I start with the 1k?Quote:
Originally Posted by Euclid440
Also should I breadknife? What is breadknifing? Is is just dulling your blade?
Its hard to capture but there are a few small chips near toe and heel. I can't visibly tell if blade is warped but when I use a sharpie and just sharpen with the blade paralell(straight across) to the stone using circles or X patterns, I notice that the toe and heal on the do not get sharpened. Maybe warped? Mayb due to the slight smile?
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You said in the original post that the chips disappear but then re-appear after honing. This could be that the edge is disintegrating because of pitting that is being uncovered the more you hone. Do you have a loup to examine the edge in detail? Another sign of this is a marked deposit of swarf in one spot when you are doing circles - this is easier to spot on a light coloured hone and is a sure sign that the edge is crumbling.
I've had my share of chippy edges recently and while what everyone thus far has said is true, there is more beyond that as well. Assuming that pitting is not an issue or the very useful comment made by Euclid is not your issue, it could be simply that the steel in question is not the finest. I've stated in other threads that my Hart Steel is a very chippy razor straight from the source. It performs much like you describe in that it doesn't seem to be as sharp as other razors coming off of the same stone. The bevel is set, you move on. But the next couple stones don't seem to improve the edge or its keenness much. So you stick with it until it falls apart. With a microscope you can watch the edge deteriorate. A layer or two of tape on teh spine (maybe three) will help to some degree. What I've found to be the best solution is to use tape to give it some strength, watch closely under the microscope at every grit level to ensure that the very edge is clean and straight (if not move back a grit to get it there), and stop before it starts to fall apart. Then keep moving up in grit to slowly nudge it forward. I would finish it on a either a higher grit stone than your 12K or a pasted strop. But if its like my Hart, don't expect it to hold that edge too long. All things being equal, it probably comes down to the quality of the steel. If this is a problem with all of your razors, then it probably something you are doing. If not, its probably the razor. You can grind away all day with it but you might not be able to get a decent edge on it. If my Hart wasn't a gift from my wife I would have put it up on eBay months ago.
Yes, stay on the 1K until the bevels come completely togeather and you have a sharp chip free edge along the entire edge.
It appears from the photos that the blade was sanded, it may have also been buffed and suffered from pitting. Pitting or over heating may cause future problems like crumbling. You will only find out by continuing to hone until you get to good steel.
You also have the beginning of a heel hook forming, I would reshape that with a small stone or the side of your 1K to round it out if not it will get worst and eventually cut you and or your strop. You will have to bevel set the heel once reshaped. There are good threads and video on doing this.
The toe was honed will too much pressure, you can see the wider hone wear on the spine tip. The toe can be honed by doing some circles with light pressure and lifting the heel just a bit. Some sharpie ink on the bevel will show you the right angle.
To hone the heel, some circles heel forward at about a 20-30 degree angle with a little pressure will bring the heel bevels togeather. Once the heel and toe are coming togeather then hone heel forward in an X pattern, that will cause a very slight pressure shift and hone the entire edge in one smooth stroke.
If the edge does not stop crumbling it may be damaged, removing more steel may solve the problem.
Bread knifing can be used to remove a chip, correct a frown and straighten an edge. It is honing with the blade edge at 90 degrees to the stone. In some cases sawing the stone like slicing a piece of bread from a loaf. There are also good threads and video on this too and there are also other variations on this technique.
A form of light bread knifing is jointing, lightly dragging the blade 90 degrees on the stone edge corner to straighten the edge when experiencing light chipping.
I also recommend tapeing the spine when learning to hone a problem razor to prevent excessive hone wear. You can also learn a lot about your technique by the wear pattern on the tape.
What gritis your diamond plate? Is it interrupted surface or continuous?
Honing for too long on a very rough diamond plate will eventually cause the edge to break up.
Michael
DMT Diasharp coarse/ X coarse. I didn't start on these but I was on the 1200 grit for about 15-20 minutes and the chips were not going away.Quote:
Originally Posted by mjsorkin
Quote:
Originally Posted by Euclid440
Great suggestions. I will try these tonight.
Ok. I reshaped the heel. I then bread knifed the whole knife. I then worked the toe lifting up a bit on the heel with light pressure (100 circles pre side). I then worked the heel (100 circles per side with light pressure). I then X stroked with light pressure heel foward for about 100 strokes per side.
The bread knifing took the chips out.
I don't want to over do it but it now feel sharp but won't cut any hair on my arm.
I moved to the 4k King. Did about 40 circles on each side with light pressure. Then did it again. I then follow this with about 100 X strokes on each side heel foward using light pressure alternating.
Feels sharp but still doesn't cut any hair on my arm. Knock on wood but no chips yet.
So what should I do?
Go back down to 1k?
Stay on 4k?
Go to 8k?
I may have bread knifed it too much.
As has been said, you should stay on the 1K until it is sharp. This cannot be reduced to some number of circles or X-strokes; the bevel isn't set until it is set. Again, it should be shaving sharp coming off the 1K and there is no point in going to the 4K until it is. Stick with the 1K until it is at least catching arm hairs above skin level and popping some of them. While it is true that you can set a bevel on a 4K stone, it will require a lot more work than on the 1K and we would not normally do that unless there was some other factor involved.
rs,
Tack
It seems the bevel may not be set. Do you know how to do the thumbnail test or other bevel set test? I say this because it should cut hair on your arm. I wouldn't move to a higher grit until I could be certain the bevel is set. Breadknifing requires extended amount of 1k work to get the sharp back.Watch the pressure on a chippy blade.
Yup, bevel is still not set. When bread knifing it is surprising how much metal you have to remove to get the bevels to meet.
Look at the edge straight down under a strong light with some magnification. If you see any shiny spots, that is where the bevels are not meeting, once you do not see shiny spots then hair test.
One way to speed up the bevel set from bread knife is to hone on a diamond plate with the spine off the hone at about a 45 degree angle until the bevels almost meet, but not quite. That will take off the corner of the dull edge and greatly reduce your time on the 1K.
You can also hone on a 600 or down to a 400 stone, post 45 degree diamond plate honing, to speed thing up.
Where you are at now depends on how much you bread knifed your edge, how thick the edge was.
I would tape the spine with 2 layers of tape to protect the spine and do circles on the 1K with a bit of pressure 20 circles at a time until the bevels meet.
Once they meet, re-tape with one layer and do 2 more sets of 20 without pressure to begin polishing the bevel. Then do full laps to even out the bevel until you have even 1K stria on the bevels.
THIS !Quote:
Originally Posted by Euclid440
One of the greatest causes of chipping is too much pressure, tho diamond plates & coarse stones are not kind to some steels.
Also the right pressure will keep the edge to the hone speeding the process & preserve the spine.