When can a razor no longer be sharpened?

[RumpleBearskin]

First, let me say thank you. The folks on the B&B forums have been an enormous source of help and encouragement. So, from all of us on the less experienced end of things, thanks.

As I am trying to learn honing I have bought several fleaBay cheapies to practice upon. I'm noticing that I can get a reasonable edge on some/most, but not on others. I know they are good steel and can take a shaveable edge, though the resulting shave is not a comfortable one.

It's seems to consistently be the razors that show significantly more spine wear that seem to not want to get sharp. The ones that have a well defined flat surface on the side of the spine that's wider than the width of the spine itself. Clearly the recipient of many prior honings.

So, the question is, is spine wear a good indicator of how much life is left in the blade? And if so, what's an upper limit of visible wear that would still leave us reasonably confident that the blade will take a fine edge?

Again, thanks ...

-- Alan

 

[M14Shooter]

As the spine wears it will change the geometry of the blade .The width of the spine is what sets the bevel angle .Tape may help with a worn spine,
Regards Mike

 

[Mr.Tee]

Yes and no. If the bevel angle is in the ballpark of 16ish-19ish degrees it wont matter how much wear it has or how ugly it looks, if honed correctly and assuming the steel is good it should shave. Very generally, if it’s too acute, you need to tape the spine, too obtuse, you will need to hone some off the spine. Really, they are never totally dead until you run out of steel. But, with lots of wear the likelyhood of issues priorly honed into the razor goes up a lot. Razors with big fat wear strips on the spine can be more difficult to hone than say a new equivalent. Stiction and skipping can become an issue with light pressure strokes. Look up “razor back beveling” on youtube. Drmatt demonstrates a technique to alleviate this issue. I have never tried it but it looks it would be helpful.

Heavily wore razors are always going to some extent, be more challanging to hone and strop. Its just easier to “oops!” and lift the spine on say a 4/8’s vs a say a 6/8’s.

Just to let you know, I bought 5/8’s new about 3 years ago. It’s my “tester” razor and it has seen the stones weekly almost that entire time. Heavy wear but still shaves like a champ.

 

[buca3152]

Don't buy anything with issues. Heavy hone wear etc. Wedges can be a problem too as some were honed freehand. Jmo.

 

[Christian1212]

As long as steel is good and you get the right angle (between like 12-25 degrees? with 15 being ideal I believe) then as long as you are comfortable shaving with it. Tape can be used to increase bevel angle on razor that has a lot of hone wear and angle is to low (or razor sticking to much to stone). However if blade has warp then you only going to be able to shave with the part of the edge where both sides touch the stone. Sometimes you can make warp work with x strokes but other times not.

Is good to practice honing on different razors but don't go trying to save every 10$ practice razor. Sometimes putting a razor away and coming back to it another week can help for stubborn razors that seem to have good steal/angle etc.

 

[Mr.Tee]

Don't buy anything with issues. Heavy hone wear etc. Wedges can be a problem too as some were honed freehand. Jmo.

Good plan. But, how many used razors have you seen listed as “Has major geometry issues”. Nope, they all say “shave ready” even if they look like a 20 year old wore out lawnmower blade.

 

[Slash McCoy]

The amount of wear to the spine is probably proportional to the amount of wear at the edge. If so, it is not much of an issue. You don't see the steel that has been honed away from the edge, but it was there and now is gone. You don't see the steel that has been worn away from the spine, either, but you see the bevel on the spine and say, "SPINE WEAR!!! Oh, the HUMANITY!!!" In truth, both edge and spine wear are a natural consequence of honing. Calculating the bevel angle will tell you if the wear is disproportional or not. If the bevel angle is outside the desired range and it seems to be affecting the shave, then corrective action can be taken. If the razor shaves to your liking, don't worry about the actual number.

Many decades of regular or heavy handed honing can create issues. Hollowground razors can become virtual wedges, and require the same honing techniques. Stabilizers can become issues as blade is honed away. Heel hook can be a problem. Nearly any of these issues can be corrected. I have a few very skinny razors that shave just fine. Down to 3/8 is generally quite practical and useful if there are no issues.

If a razor is unusual in size or geometry or has problems you don't know how to deal with, just set it aside. Some day you will come back to it armed with more skill and experience, and make a shaver out of it.

 

[buca3152]

Good plan. But, how many used razors have you seen listed as “Has major geometry issues”. Nope, they all say “shave ready” even if they look like a 20 year old wore out lawnmower blade.

I hear you. But if you look at the photos carefully you can usually see issues that will give you trouble.i would much rather buy an off brand in great shape than a "desirable"brand in rough condition. But that's me.

 

[RumpleBearskin]

Thanks for all the help and suggestions. Very useful information in here. Much of it seems to come down to bevel angle, with a wide range of "acceptable" angles offered.

I had a specific case in mind when I posted this, an old Griffin XX that I just can't seem to get to treetop. In this specific case I'm measuring (calculating) the angle to be about 21 degrees. There's significant hone wear on the spine and I was wondering if this razor had just gotten to the point that it was "done".



My "sharp" razors all have bevel angles between 16 and 18 degrees. I'm thinking that the bevel on the Griffon is just to obtuse for my tastes.

Is the recommended procedure to tape the edge and try to remove spine thickness? To get down to a calculated 17 degree angle I'd have to go from 4.5 mm to 3.7 mm which seems like a lot of steel to remove.

Should 20+ degrees still get me a "sharp" razor and I just need to work on technique?
Should I try removing spine thickness to decrease the bevel angle. And if so, what are the suggested methods?

Thanks again for all the help. You guys are invaluable to us newbies.

 

[Christian1212]

My guess is you might have gotten something wrong with the measurements. If you want to get that razor shaving I would try 1 layer of tape, and then 2 layers if 1 did not work (Will be quick to test and if it is wrong it won't be a lot of lost time). Then if that doesn't seem to be working I would consider removing steel. Although if tape did not fix the problem I personally would give up on that razor or put it away and come back to it a few months later.

One of my razors is close to the same size as yours in the picture. It takes meh edge with no tape, but with a layer of tape the edge is great. The razor is in the daily shaving rotation and will probably be there for a while.

Best of luck

 

[Slash McCoy]

Sure, you can do that. If you can't get it sharp as it is, whaddaya got to lose? Try taking it down to just 18deg initially. No sense doing more than you have to. A bevel angle around there can be a very mild and pleasant shave. If it still doesn't suit you, take it down another degree or a bit more. If it still won't shave, the angle is not the problem. Any 17 degree razor of decent steel will shave, with good honing. Any 18deg razor, for that matter. Plenty of near 19deg Gold Dollars shaving happy faces out there. But 21deg is asking a bit much.

I thin a lot of spines, because my GD mods are all at around 16 to 17 degrees. What I do is not for the faint of heart. I take a piece of a tin can lid and fold it over the edge in lieu of tape, then take it down into the ballpark on a belt sander loaded with a 200 grit belt, clamped upside down in a bench vise, with most of the pressure on the spine. Then I hit 400, 600, and 1k grit paper glued to a 12x12 polished marble tile or one of my acrylic blocks I use for lapping film, without the can lid, taping the edge up to the 1k. At the 1k stage I lose the tape and concentrate on restoring full parallelity (new word?) between spine and edge bevels, and ensuring I do indeed have a good end to end bevel set at the edge. From there, normal film progression, finishing on my lapped and pasted balsa as per The Method. When modding a GD, before the 1k stage I do final profiling of heel and nose, hand sanding, and polishing, in that order. You could try something similar on your Griffon. If it comes out looking more like a wedge than a hollowground, take it down to 15 degrees so your final microbevel can comfortably be at 16 or 17 degrees and bobs yer uncle. Otherwise don't. Sometimes a razor, due to wear, gradually shapes itself into a near wedge even though it started out as a hollowground.

BTW, can you tell us how you measured and calculated your bevel angle? A mistake can mean you end up doing the opposite of what would actually work best.

 

[stone and strop]

I have a hard time believing that the bevel angle is 21 degrees with all that wear.
It looks like it has a frown but is hard to tell with the light.
Just because it will not treetop does not mean it won't shave fine. How does it shave?
If it does not shave well then there is something else going on. It should be able to take an edge fine unless the steel is not so good.

 

[RumpleBearskin]

Great suggestions and questions! Thanks again.

Measurements were an average of 4 points along the length of the blade. Blade widths were from the apex of the edge to the farthest back edge of the hone wear strip on the spine. Spine widths were across the hone flats. All measurements were taken with digital calipers. I think the techniques were right because the angles came out reasonably with my other razors...

The razor will shave, but there's far more resistance than my other razors, and it doesn't provide as close a shave as I like. That's what started my explorations ... Well, that and a naturally inquisitive nature. Oh, and the need to bend the world to my will. That razor should be able to shave nicely, or so says my brain.

Agreed, I could write it off or set it aside. But as another commenter mentioned, what do I really have to lose with a cheap ebay razor?

So I think I'll go for the spine narrowing. I don't have the grinder, but I do have a Norton 600 and lots of available time ... I'll let you all know how it works out ...

Thanks again.

 

[stone and strop]

I would not intentionally thin that spine at all.
What is the thickness of the spine if you don't mind?
Sorry, just re-read your other post. says you razor spine is 4.5mm. This translates to.177 in imperial measurement. Your razor looks to be about 5/8 "?
This would put the bevel at roughly15.8 degrees.
Before you do any alterations please post your numbers here.
I'm not trying to be argumentative but rather trying to make sure you do not go ahead with unnecessary altering without being 100% sure.

 

[RumpleBearskin]

@stone and strop, here are the original measurements.

4 points measured along the length of the blade, heel to toe.
Measurement #: apex to back edge of hone wear strip, Spine Width, Calculated bevel angle
1: 12.56, 4.44, 20.36
2: 12.21, 4.44, 20.95
3: 12.16, 4.48, 21.23
4: 12.62, 4.60, 21.00
Avg: 12.39, 4.49, 20.88

Trangle calculations were done at: Triangle Calculator

And I don't view your comment and request as argumentative. I appreciate the good intentions and will take all the help I can get. I've only been straight shaving about 3 months (90+ shaves so far) and honing for less than that. I am supremely grateful for the voices of experience available here.

For the record, I have already begun. Two layers of tape on the blade edge, replaced as soon as I see steel on the edge. Using the Norton 600 grit stone. Current measurements are:
1: 12.56, 4.17, 19.11
2: 12.21, 4.19, 19.76
3: 12.16, 4.35, 20.61
4: 12.62, 4.49, 20.49
Avg: 12.39, 4.30, 19.99

Since the toe seems to be thicker than the heel, I'm starting to try to even it out to a consistent spine width across the length of the blade. Shooting for something under 19 to then do a sharpening progression and try a shave test.

Continued thanks to all for the assist!

 

[stone and strop]

This was a very heavy handed individual that owned that razor. He must have used torque as well to make things wear unevenly. Poorly honed razors are abundant.
It must have been a fairly large razor to begin with as well. Soon you will be thinning the shank by the look of it
Good luck with it!

 

[Slash McCoy]

@stone and strop, here are the original measurements.

4 points measured along the length of the blade, heel to toe.
Measurement #: apex to back edge of hone wear strip, Spine Width, Calculated bevel angle
1: 12.56, 4.44, 20.36
2: 12.21, 4.44, 20.95
3: 12.16, 4.48, 21.23
4: 12.62, 4.60, 21.00
Avg: 12.39, 4.49, 20.88

Trangle calculations were done at: Triangle Calculator

And I don't view your comment and request as argumentative. I appreciate the good intentions and will take all the help I can get. I've only been straight shaving about 3 months (90+ shaves so far) and honing for less than that. I am supremely grateful for the voices of experience available here.

For the record, I have already begun. Two layers of tape on the blade edge, replaced as soon as I see steel on the edge. Using the Norton 600 grit stone. Current measurements are:
1: 12.56, 4.17, 19.11
2: 12.21, 4.19, 19.76
3: 12.16, 4.35, 20.61
4: 12.62, 4.49, 20.49
Avg: 12.39, 4.30, 19.99

Since the toe seems to be thicker than the heel, I'm starting to try to even it out to a consistent spine width across the length of the blade. Shooting for something under 19 to then do a sharpening progression and try a shave test.

Continued thanks to all for the assist!

If you have a consistent spine thickness, then you need a consistent blade width. IOW, don't worry about a consistent spine thickness. Let it happen naturally. The bevel angle should end up the same or very close to it, from end to end. Where the blade is wider, the spine should be thicker proportionally. And vice versa.

Normal error in measurements can easily skew the final figure for bevel angle, by .2 deg or so. And in the shave, you positively will not notice a difference of a half degree or less, anyway.

Sometimes overthinking can cause errors, be they small, or great.

Finally, if the calculator you are using is solving for a right triangle, then you must enter HALF the spine thickness, and double the resulting angle. It will come out different. What you have is an isoceles triangle, and to solve it you take half of it which is a right triangle.

Well I just checked your math and it is correct, anyway.

 

[RumpleBearskin]

For those of you that were wondering where this ended up, I have proven myself to be a true newbie.

While I claimed I was measuring to the back of the hone wear strip, I was in fact only measuring to the edge side of the wear strip. Obviously that shortened the measurements of the blade width and provided a calculated bevel angle that was significantly higher than the reality in my hands. After some time of scraping on the spine with the edge taped, I repeated all measurements (as opposed to only remeasuring the spine width), and discovered my error. I guess now I'm the "heavy handed" individual as opposed to a previous owner.

So now my razor has a calculated bevel angle of about 16.7 degrees.

I went through a 1k bevel setting and then then 4k, 8k Norton progression and finished on a Nanny 12k followed by .5u, .25u and .1u diamond on balsa progression. To be honest, I think I rushed it all the way through because it wouldn't tree top until I hit the 12k, and then not very well. I did shave with it this morning, at least a WTG pass on my cheeks. Still a lot of pulling, but at least I know now that it's not a fat bevel. Guess I now have an excellent opportunity to practice my bevel setting ...

Many thanks to all for all your assistance. I have learned a lot through this process and will carry it forward as I go on. If I can now learn to actually do what I say I am doing, things may work out a bit better for me.

 

[Slash McCoy]

All I can see in my browser is a thumbnail. If you could post a full size pic it might be helpful. It looks like you have or had a bit of a frown.

With the bevel fully set at 1k grit, the razor should shave arm hair at skin level with ease. Should treetop at 1/4" after the 12k grit. Probably won't, before the 12k. Might treetop at 1/8" after 8k.

Did you set the bevel using the burr method? And perform a sharpie test? With a frown, it is very likely that part of the blade has no proper bevel.

You have ground away a good bit of steel from the spine, now. So you may as well get that frown straightened out. That will make subsequent honing very easy and it should end up being a good shaver for you.

 

[RumpleBearskin]

I had tried setting the bevel with Lynn Abrams' "circle method", but don't think I actually followed his procedure faithfully. I want to try that again since it looks so easy and he claims results are so reproducible. I'll save the burr method for another day since I have little confidence in my ability to see/feel the desired/required burr.

As for the pictures and the frown, they are attached and I think you are right, there is a slight frown. I'll give the Sharpie test a try and see if I can flatten the edge.