What's new

Chipped blade.

I've got a pretty old (1890s) straight with a pretty significant chip on the edge. I spent about 20 minutes on a Chosera 600 trying to get rid of it but it looks the same as it did before I did anything. What stone should I use? My 180/120 flattening plate? If so, would Super 33 tape be good enough to protect the spine?
 
Can you post a pic of the razor and chip? That would help in determining how significant it is. I find a fine DMT works pretty expeditiously with chips, used with an up-and-down motion. Sometimes I tape the spine with electrical tape, sometimes I don't; it depends on the situation. If I do use tape, I usually remove it after the fine DMT for the rest of the process.
 

Slash McCoy

I freehand dog rockets
20 minutes on a 600 is NOTHING when dealing with a big chip. I sometimes go down to 100 grit and as the bevel is ground down toward the bottom of the chip, I begin progressing upward through a few grits so that by the 1k stage the chip is gone and bevel set. Even just setting the bevel on a new razor I typically go in with my 320 Kuromoku, then 600, then 1k sandpaper or Naniwa or 30u film, and then 9u film and the rest of the progression. In general 600 grit is a good starting stage for minor edge repair or setting a bevel on a razor that really needs it.

You are not done until you are done. Time is not the metric to use. Nor is lap count. Go until that chip is gone. Be sure that you are not placing all the pressure on the spine. If all the pressure goes to the spine then you aren't going to make much progress on the edge, and you will be grinding the spine down too thin too quickly to keep up with the edge.

And speaking of that, with a hollowground razor I normally do NOT use tape, unless I have calculated the bevel angle and found it to be under about 14 degrees. Paradoxically, many honers use tape exactly at the worst possible situation, which is when a lot of steel is to be removed from the edge. If the bevel angle is within normal range, all you have to do is balance the pressure appropriately so that edge and spine wear proportionally. You don't have to torque the edge strongly into the hone, just use a slight torque and hone normally.

To hone out a chip, begin with heavy pressure, about the weight of your arm. As the chip disappears begin lightening to medium pressure, about the weight of your forearm. By the end of the repair and bevel set stage, you should be down to about the weight of your hand. Slurry on the hone is a good thing, at this stage. You will get less microchipping, less burr/fin, better bevel that will polish up nicer. When removing a chip, there is no need to raise a burr. When the chip is gone completely, your bevel is probably set.

It is perfectly okay to do sets of say 50 or 100 circles on one side, then the other, though, especially to do the initial heavy lifting. You will remove more steel faster. But it is up to you, and raising a burr is not necessary here, and ordinary alternating laps will gitter done.
 
This is the only picture I have that you can see the chip. It's near the heel.
20191129_195047.jpg
 
Ya, that's not too bad at all.
There is not much hone wear on the spine yet so I would check the angle and if you can and keep in a god range I would remove most of it on W/D at a 45degree angle then reset the bevel.
If it is in the high range then just hone away as Slash has said.
 
Funny thing about chips, taking out the last 1/3 of one seems to take 5x longer than it took to remove the first 2/3.

Keep the working surface of the stone lapped fresh so it doesn't load and slow down. Yes, Super 33 is fine but change it regularly so you keep the angle as consistent as possible. Keep the blade torqued to the edge.
 
I agree with what Slash and everyone is saying, its not too bad and just keep going. It seems to take long because as you remove the chip it will get shallow but will widen slightly. If you so 50 or 100 laps as Slash suggested and then inspect in between a full progression with a 10X loupe, you will see how the chip progresses and how the steel reacts. I tend to use my loupe after a full progression to see how the chip is being removed.....when in doubt inspect to see how things are going before doing more progressions so you know your on the right track.
 
I agree, that seems a simple affair. I would use tape on the spine with a fine DMT (up-and-down half-laps) until the chip is gone, then remove the tape and hone until it is passing the thumbnail test (almost certainly should be already with that much material being removed). Then switch to x-strokes with a 1k until the up-and-down scratches have been replaced by more diagonal ones, coinciding with a less aggressive grab in applying the TNT.
 
Last edited:
I removed chips for the first time today - from a badly pitted Imperial 20507 today. After about an hour making very little progress on my Naniwa Chosera 1k, I put the razor (using Super 33 tape) on my cheapo 400 grit diamond plate, raising the spine slightly off the stone, using edge leading strokes with gentle pressure, and in little time the chips were gone. I then set the bevel on the 1k and did a full progression to HHT.

Do you guys rest the spine on the stone, and do you use edge leading and/or spine leading strokes when removing chips?

I should add that in my case the $20 razor is so badly pitted that the pitting has compromised the edge of the razor. But no complaints, the razor has served its purpose and I have learned a lot.

And the next time I do this, I may use P400 or P600 wetordry sandpaper, or spring for an Atoma plate.

Photo from before I removed the chips.

20210216_034253676_iOS.jpg
 

Slash McCoy

I freehand dog rockets
I ALWAYS ensure that the spine is reduced proportionally to the edge, and ESPECIALLY SO when I am removing a lot of steel from the edge. This is when it is MOST important, because in one session you are removing possibly several decades worth of steel from the edge. Several years, minimum. So no, I never ever raise the spine off the hone and unless the bevel angle is excessively acute, or it is a wedge, or there is some other reason that escapes my mind at the moment, I don't tape the spine, either. By "saving" the spine from wearing at the same rate as the edge, you are doing the razor no favors. The damage is not done by normal honing. The damage is done by chipping the edge in the first place. There is no point in exchanging one sort of damage for another.

The good news is you may never notice. The bad news is the razor should last for generations but if the razor is repeatedly chipped and then honed with tape, it won't be so great any more at some point. The mediocre news is if somebody really wants to do remediation all they have to do is thin down the spine. The other mediocre news well, you can figure it out.

Well, it does appear that you have a near wedge razor there, so sooner or later, probably much later, it will get honed flat anyway, and meanwhile practically every time it is honed it will be honed or at least finished with tape. So no biggie about the remediation. And likely the bevel angle is acute enough to allow for a repair session with the spine taped.
 
Top Bottom