Glassing/Resetting an Edge?

[Frank Shaves]

Lapping Arks is subjective. I would try different finishes until you are happy.

I like finishing a hard Ark on 240-grit wet/dry sandpaper. 220-grit SIC is too coarse for my taste and 400-grit wet/dry is too fine. Go figure, right?

I love the finish on my Dan's translucent Ark. According to Kim (at Dan's), they finish the hard black and hard translucent Arks using what they call recycled grit supplemented with fresh 90-grit SIC - whatever that equates to .

Again, experiment until you find what you like. Lots of folks like much finer finishes than me. Did I say that I also don't like liver.

 

[Frank Shaves]

Attaining really close to flat using SIC is difficult. Once you are close to flat, you can switch to wet/dry sandpaper. You may go through a few sheets, but you may also save yourself time and grief.

 

[Gamma]

Thanks, and I actually just watched your video on lapping arks which was really helpful. My arks are 8"x3" so probably too big for my ultra sharp diamond plate. The highest grit on gotgrit was 500, so I guess I can look elsewhere for 600 or grab some w&d for that.

Yeah, an 8x3 Ark is a lot for Diamond plate to deal with, unless maybe the DMT DIAFLAT.

500x should be ok, SIC will break down a good amount so you will be in the ballpark.
follow up with 600x w/d. You really don't need to go finer than that. Occasionally I do go higher but it's never necessary.

If you have amazon prime, you can get a decent size granite surface plate for $36 - a sheet of w/d on top to protect it will work.
Putting a surface plate in the sink is not fun tho..... they're heavy and the corners can hurt the sink. I've done it but I used rubber pads underneath.

There are places that sell machined flat steel plates, but it's pricey. A float glass plate is about $25, not bad but gotta be careful. A 10x4 DMT is about $120, use the back to lap but put w/d down as a sacrificial layer.
If the lap surface is flat, the Ark can come out flat. If the lap plate's surface is convex, then the Ark can wind up with a concave surface, and vice versa. I am a stickler for flatness, esp with a finishing ark, so having a flat lap plate is nearly the most important thing to me.
I like to lap in the sink because clean up is easy, and having running water there helps me keep the slurry level across the plate.

 

[rhgg2]

As for the bevel, it was originally set by Ulrik of Koraat Knives, so I assume it was set correctly initially at least. I've never (deliberately) reset it but it's still possible I've screwed it up with poor technique since.

I believe the Koraats are honed with tape by default. If that is the case and you are not using tape then you could be missing the edge and just honing the back part of the bevel. So you would either need to use tape or grind away on a low grit stone without tape in order to set a new bevel at the more acute tape-less angle.

However as someone who still spends all my honing time making mistakes I would second the advice to get someone else to work on a nice razor like this!

 

[algebro]

I believe the Koraats are honed with tape by default. If that is the case and you are not using tape then you could be missing the edge and just honing the back part of the bevel. So you would either need to use tape or grind away on a low grit stone without tape in order to set a new bevel at the more acute tape-less angle.

However as someone who still spends all my honing time making mistakes I would second the advice to get someone else to work on a nice razor like this!

Oh wow, I emailed Ulrik and you're right! He honed it with tape and I've been honing it without. Could that cause the results I've been seeing?

 

[H Brad Boonshaft]

Maybe but probably not. About 30-40 laps on a 4-5k will erase a taped bevel and cut a new full bevel.

If you want to make sure, ink the bevel with a colored Sharpie and do a single lite lap. I like Red or Blue, it is much easier to see without magnification, black can look like a shadow.

Or just use tape, there is no downside to using tape. Actually learning to hone with tape can save you from trashing a spine.

What do you see, when you look straight down on the edge?

 

[algebro]

Maybe but probably not. About 30-40 laps on a 4-5k will erase a taped bevel and cut a new full bevel.

If you want to make sure, ink the bevel with a colored Sharpie and do a single lite lap. I like Red or Blue, it is much easier to see without magnification, black can look like a shadow.

Or just use tape, there is no downside to using tape. Actually learning to hone with tape can save you from trashing a spine.

What do you see, when you look straight down on the edge?

I'll try the sharpie thing tomorrow. As for tape, arent spines supposed to wear at the same rate as the edge so that the angle stays consistent? I was under the impression that using tape would cause geometry problems in the long run.

 

[H Brad Boonshaft]

Tape is one of “those” questions. Some folks love it and use it, some hate it and say it ruins a razor.

Many a nice razor has been trashed by a new honer learning to hone needlessly, too many laps, too much pressure on aggressive stones. It could all have been avoided with a single layer of tape.

Some razors that have had the spine worn excessively (not honed with tape) will not hold an edge, the fix is a layer or two of tape.

A taped razor has never stopped shaving because of a “Geometry Problem”.

Do yourself a favor tape the spine, once you have Mastered honing, then decide if you want to continue to hone with tape. Hone the razor with tape and shave, hone it again without tape and see if you can feel the difference, I doubt it.

So, Ulrik is using tape… Might ask yourself why.

 

[algebro]

Tape is one of “those” questions. Some folks love it and use it, some hate it and say it ruins a razor.

Many a nice razor has been trashed by a new honer learning to hone needlessly, too many laps, too much pressure on aggressive stones. It could all have been avoided with a single layer of tape.

Some razors that have had the spine worn excessively (not honed with tape) will not hold an edge, the fix is a layer or two of tape.

A taped razor has never stopped shaving because of a “Geometry Problem”.

Do yourself a favor tape the spine, once you have Mastered honing, then decide if you want to continue to hone with tape. Hone the razor with tape and shave, hone it again without tape and see if you can feel the difference, I doubt it.

So, Ulrik is using tape… Might ask yourself why.

Makes sense, thanks for the advice. I added a layer of super 88 today and took the purist from 5k-12k. Light and very light pressure on the 8k and 12k respectively and no swarf on either. The bevels on koraats are really thin so it's hard to judge when to progress based on the stria but hopefully there will be some improvement.

Going to give that a shave test later on and will report back. Also going to lap the arks once the grit arrives.

 

[H Brad Boonshaft]

“I added a layer of super 88 today and took the purist from 5k-12k. Light and very light pressure on the 8k and 12k respectively and no swarf on either. The bevels on koraats are really thin so it's hard to judge when to progress based on the stria but hopefully there will be some improvement.”

How much magnification are you using?

You hone a razor as it needs to be honed, depending on what you see, looking at the bevels and edge.

When you look straight down on the edge, that do you see.

You can reset a bevel on an 8k but likely will need some pressure, once you have an even stria pattern and straight edge, no shiny reflections. Once you have cut a new edge, then you lighten up on the pressure to refine the bevels and edge.

When you move up to the 12k you start with some pressure to remove all the 8k stria and ensure that the edge is still free of shiny reflections. Once all the 8k stria is removed, you lighten up on pressure and refine the bevel and edge.

Final 12k laps should be on a clean stone with light pressure. A Carson 60x100 MicroBrite handheld scope is $10-15 and will give you a good view of the bevels and edge.

You cannot hone a razor blind. It should not be difficult to see if all the bevel stria are uniform and the edge, chip free. You simply remove all the previous stria with the following stone. Start each stone in the progression with some pressure, finish each stone with lite pressure.

 

[SliceOfLife]

Hi all,

I've been struggling for a long time on one particular razor and at this point I'm wondering if has been over honed due to all the troubleshooting. I've taken it to 5k, 8k, 12k, and a Dan's translucent ark several times and while it shaves pretty close, it almost always causes a noticeable amount of harshness and razor burn. None of my other razors do this so I don't think it's just user error with the shave.

At this point I'm wondering if there is some way to reliably "reset" the edge and take it all the way back to a bevel set. I was hesitant to put it straight on a 1k because I don't want to end up just overhoning it further (in the event that it is actually overhoned). I've heard mixed reports about whether "glassing" it by shaving a jar or something like that works so I wanted to ask for your alls' opinion first.

Thanks!

In my experience feels sharp but causes irritation MOST often means edge is crumbling in the shave. What's the razor? Got a good scope?

Could be razor too thin ground for the steel (the tape rec above may fix that if it's good steel with bad geometry... maybe the one case I'd consider tape... though personally I'd just fix the razor by trimming it).

Could be you're not being careful enough when flipping on the ark (or any stone, but ark is most likely) and are causing too much elastic deformation and degrading edge durability; causing it to fail unusually early... this generally happens on the strop but it CAN happen in the shave.


Could be something else entirely, but those would be the first two things I'd check.


edit: Saw it's a koraat and googled em... Google says they're honed with tape before being sold... which means if you AREN'T using tape... your honing is doing Squat... and their edge is probably all kinds of degraded from never being touched up (and one of the reasons I hate tape is in MY experience it makes stropping both speed up edge degradation AND be far less effective in general... both of which manifest in the issue you describe.)


Google also says they're like 20* angle... add a layer of tape to that and you're holding more of a knife than a razor... So it's definitely not that the razor is too thin ground. Honestly 20 degrees feels like shaving with a stuffed animal to me... but the edge should be darn near indestructible unless the steel is basically poop.


Solution; hone with tape... or spend a lot of time undoing the tape angle on a low grit hone and rebuild the edge from the ground up.

 

[ZeelandsRoem]

Saw it's a koraat and googled em... Google says they're honed with tape before being sold

Small adittion: in the past, at least, Ulrik used Tesa duct tape. Not sure if he's still using that tape nowadays, but as far as I remember, that tape is thicker than Kapton or even electrical/insulation tape. If the OP wants to use the same tape again, then mailing Ulrik to get the part number shouldn't be a problem.

 

[Darth Scandalous]

Google also says they're like 20* angle

Don't know about OP's razor but my Koraat "14 2.0" is right about 16 degrees (without tape).

 

[Wid]

I used Super 88 on my Korrat and it worked great.

 

[alex1921]

I used Super 88 on my Korrat and it worked great.

Same here. All my Koraats get a layer of super88 and they shave fine.

To the question of switching to a different type of tape or no tape at all. I have honed plenty of razor where I start with tape and once the bevel is set I go to the next stone without tape. A 4k shapton glass takes no time to make it happen.

Another reason to use some sort of magnification so you know what you are doing and not just honing blindly rubbing steel on a stone.

 

[algebro]

Small adittion: in the past, at least, Ulrik used Tesa duct tape. Not sure if he's still using that tape nowadays, but as far as I remember, that tape is thicker than Kapton or even electrical/insulation tape. If the OP wants to use the same tape again, then mailing Ulrik to get the part number shouldn't be a problem.

When I emailed him he said he uses cloth tape that is 0.15mm thick, which is slightly thinner than super 88. I went ahead and used super 88 anyway because I assume it's close enough. Shave test incoming tonight.

 

[algebro]

Alright, the shave test after the taped 5k-12k progression was definitely a success. Noticeably more comfortable with absolutely no sting from the alum or splash.

Obviously there are a lot of variables here, like technique, addition of tape, lack of an ark, etc. Going to shave a couple more times off the 12k to make sure I have a good baseline and then I'll reintroduce the ark after lapping.

 

[SliceOfLife]

Yeah I think you'll probably be fine to reintroduce The Ark. If you were honing it without tape then that was definitely the problem. I had the exact same thing happen when I was starting out and I bought a Filharmonica as a splurge as shave ready... the first couple shaves were okay but not up to my standards so I kept trying to touch it up and wasn't getting anywhere... it's actually why I eventually bought a good microscope. Looking at the edge under the scope after a bunch of honing, I could clearly see that there was a secondary bevel and I had just been polishing the hell out of the bevel without touching the edge. Rebeveled it and wiped out the dual bevel then honed... and it shaved great

 

[algebro]

Well...I tried lapping the arks on a steel baking sheet that seemed pretty sturdy, but it turned out to be a bit of a disaster. I realized after about half an hour that it wasn't actually flat, but was bowing downward as I was lapping, which explains why it took so long to get the sharpie grids off in the center of the stone. Basically, the arks are probably LESS flat than before

Additionally, there were small chips in the corners that weren't there before I started lapping.

Guess I'm going to have to try and find something else to lap on. Does anyone have any other cheap suggestions before I go the granite surface plate/giant DMT route? There is this thing which promises "dead flat" and seems promising:

Amazon.com

Trying to minimize the amount of big junk I have to collect if possible.

 

[Frank Shaves]

Most tiles aren't all that flat. SIC will eat granite so fast your head will spin.
Even if a granite slab is flat to start, it will be not-flat fast. If you put down a sheet of 220x w/d paper to protect the stone, that can help.
Some sheets of glass are flat, others are not. Glass cracks so I don't use it for lapping.

Keith (@Gamma) is right about glass. SIC eats glass fast causing the glass to dish, get thinner and eventually crack.

In hindsight this is obvious, the glass dishes deeper in the center causing the corners of the stone to slope down. If you want the entire face to be flat, need to get back to flat before finishing the job.