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crimedog72
12-13-2012, 01:48 AM
My early adventures in sharpening have produced a knife (10" Sabatier Carbon Chef's) where part of the edge is ground down a little past where the bolster extends. So part of the edge won't hit the board until I grind down the bolster a bit. Any advice for doing this, other than using my coarsest stone and having at it?

franzb69
12-13-2012, 02:05 AM
Belt sander or an angle grinder. Just be careful and don't go crazy on the grinding.

Benuser
12-13-2012, 02:40 AM
Use sandpaper, and level the finger guard with the relief bevel. I use sandpaper on linen, grit P120 to start with.

zitangy
12-13-2012, 04:32 AM
Belt sander or an angle grinder. Just be careful and don't go crazy on the grinding.


+1
a. I wld prefer the belt sander.. sort of roll over the protruding part of bolster

b. IF I have to use an angle grinder, either I secure Knife has to be strongly secured or secure the Angle Grinder (AG) and bring the knife to the AG. I prefer the latter as it is safer. Ag with variable speed makes sense. IT does seem that there are more grit option on a belt sander than an angle grinder.

rgds
d

franzb69
12-13-2012, 06:46 AM
it would be the fastest way. just finish with sanding paper when you think you've done enough.

Don Nguyen
12-13-2012, 09:05 AM
If you don't have a belt sander/grinder, a sharp file, vise, and cautious patience will go a long way. Afterwards you can clean up with sand paper.

chinacats
12-13-2012, 10:59 AM
Absolutely the worst thing about the Sab's...mine is due for more work again.

:cheffry:

Lefty
12-13-2012, 11:49 AM
I wish you lived close by. I'd borrow it for a few days and tune it up for you, just because. :D Is there anyone local who could do it for you?

JBroida
12-13-2012, 12:12 PM
at least sab bolsters are thin... german bolsters are beastly

Lefty
12-13-2012, 12:26 PM
That's true. It depends on the Sab, but in general, you're right. This is a minor annoyance, though I think Sabs (most) are worth the little bit of extra work.

crimedog72
12-13-2012, 12:32 PM
not sure I have easy access to a belt sander or angle grinder. will check in with some friends, but may well end up filing this down.

after thinking a little more, I see why my original idea of using a stone wouldn't be so good.

it would be best to grind from the side and make the bolster flush with the side of the blade, yes?

Lefty
12-13-2012, 12:56 PM
I match the angle up with the primary (in sharpening terms) bevel. This allows you to sharpen just like it's a Japanese knife.

Benuser
12-13-2012, 12:58 PM
Put a strip of sandpaper on your stone, and perform edge trailing strokes as you were stropping.

Don Nguyen
12-13-2012, 01:07 PM
You could either file down the sides to match with the blade face, or you can file from the choil forward. I prefer the choil approach because it wont leave you with large scratches on the blade face and is easier to clean up, but it really depends on the knife and the bolster.

crimedog72
12-13-2012, 01:19 PM
I match the angle up with the primary (in sharpening terms) bevel. This allows you to sharpen just like it's a Japanese knife.


this is essentially sharpening the bolster as if it is part of the edge, yes?

crimedog72
12-13-2012, 01:21 PM
Put a strip of sandpaper on your stone, and perform edge trailing strokes as you were stropping.

the end result here would be that the bolster is flush with the face of the blade?

crimedog72
12-13-2012, 01:23 PM
You could either file down the sides to match with the blade face, or you can file from the choil forward. I prefer the choil approach because it wont leave you with large scratches on the blade face and is easier to clean up, but it really depends on the knife and the bolster.

you are suggesting here to remove the entire portion of the bolster that extends below the handle, starting from the choil and moving forward, correct? interesting suggestion, will have to take a closer look at the knife and see how that would change my grip/hand position.

Jmadams13
12-13-2012, 02:01 PM
Here I what a freind of mine did for me on a old K-Sab if this helps. He did take a lo off as I was going to convert into a suji, but gives you an idea

http://i.imgur.com/Wh2Ym.jpg

Benuser
12-13-2012, 03:41 PM
Crimedog72 wrote:
the end result here would
be that the bolster is flush
with the face of the blade?

Exactly. You don't need to remove the entire finger guard, as Jmadams13's picture shows.

Jmadams13
12-13-2012, 10:32 PM
I only had mphim remove it completely, as I was converting it into a slicer. This is what the grind looked like when rescued it. It's the same idea tho, meaning grind it down so the edge is still servicable with out the finger guard getting in the way.

http://i.imgur.com/MZlOQ.jpg

Lefty
12-13-2012, 11:21 PM
The craziest part is, that knife was very likely sharpened on a grinder before you saved it, yet the person doing the damage didn't think to take the finger guard back while working the edge. That all could have been avoided. Sheesh!

Benuser
12-13-2012, 11:28 PM
That explains a lot! I was wondering about the regularity of the heel area.

Jmadams13
12-13-2012, 11:34 PM
Probably why the antique store practically begged me to take it, lol. Turned out to make a nice slicer though, even with the 1/4"! spine at the heel.

Anyways, enough hijacking on part. Crimedog, any pis of your knife, so we can get an idea of how far you need to go?

Jmadams13
12-13-2012, 11:36 PM
The craziest part is, that knife was very likely sharpened on a grinder before you saved it, yet the person doing the damage didn't think to take the finger guard back while working the edge. That all could have been avoided. Sheesh!

Yeah, there were grinding marks all over the knife. I was able to get a lot of them out, but some still remain, bummer

crimedog72
12-14-2012, 02:17 AM
12077
12078
12079
12080

not the best photos, but hopefully they'll give you an idea. turns out i do have access to both a belt sander and angle grinder, so that may help.

my first attempt at attaching photos, will have to figure out how to make them appear w/o clicking the links.

franzb69
12-14-2012, 02:27 AM
might help you to attach pictures:

http://social.msdn.microsoft.com/Forums/en-US/vbgeneral/thread/33bf2119-5f56-40b2-a689-d437ec09e550/

crimedog72
12-14-2012, 02:39 AM
1208612087120881208912085

better?

franzb69
12-14-2012, 03:17 AM
much better

=D

pentastich
12-30-2012, 11:29 PM
I have some older knives with the same problem. Could I put the knife in a vise and use a Dremel tool to do the grinding? I don't have a belt sander or angle grinder.

sachem allison
12-30-2012, 11:48 PM
I have some older knives with the same problem. Could I put the knife in a vise and use a Dremel tool to do the grinding? I don't have a belt sander or angle grinder.

yes, you can. Make sure you wrapp the blade so, you don't scratch it up and go slow and easy. and actually if you use the finer drum sander it will work cleaner and better then the grinfing stone attachment.

pentastich
12-31-2012, 01:03 AM
yes, you can. Make sure you wrapp the blade so, you don't scratch it up and go slow and easy. and actually if you use the finer drum sander it will work cleaner and better then the grinfing stone attachment.

Cool. I'll save it up until I have some idea of what I'm doing (noob :-) ).

pentastich
01-01-2013, 10:08 PM
I only had mphim remove it completely, as I was converting it into a slicer. This is what the grind looked like when rescued it. It's the same idea tho, meaning grind it down so the edge is still servicable with out the finger guard getting in the way.

http://i.imgur.com/MZlOQ.jpg
One of the knives I have is a soft stainless chefs knife that looks somewhat like the one on the picture. In particular, there is an area of blade that will have to be removed to match up with the main body of the knife. How would you go about evening up the blade? Sandpaper on a stone?

If fixing this is an advanced technique I could put it off until I have more experience. I suspect that the knife is worth less than what it would cost to have a pro work on it.

Benuser
01-01-2013, 11:06 PM
Picture please.

pentastich
01-02-2013, 02:25 AM
Picture please.
Here are pictures of two knives of mine that seem to have this problem. The black handles knife is a Tramontia. The brown handled knife is a Mundial.
https://picasaweb.google.com/lh/photo/uEANv8dh4LsW6LOCawDofY5WadXitWz3_weOxcM2GSw?feat=d irectlink
https://picasaweb.google.com/lh/photo/H0xP0grDb5K5kB6TAfkdoY5WadXitWz3_weOxcM2GSw?feat=d irectlink
https://picasaweb.google.com/lh/photo/O--IaOCUxlH133u_pU_Iio5WadXitWz3_weOxcM2GSw?feat=dire ctlink

pentastich
01-02-2013, 02:59 AM
Picture please.
The links I posted first are to picassa images, but don't display correctly (although if you open them in a new window they work). Here's another attempt. Sorry for the confusion.

Here are pictures of two knives of mine that seem to have this problem. The black handles knife is a Tramontia. The brown handled knife is a Mundial.

https://lh3.googleusercontent.com/-OdQTXQ1U1ZA/UOPeKK3XbQI/AAAAAAAACUQ/qiqSu03Kx3g/s400/IMG_20130102_015835.jpg

https://lh5.googleusercontent.com/-1PyqGWCtEmE/UOPeKLblZSI/AAAAAAAACUM/gVhg-yxzMXM/s400/IMG_20130102_020221.jpg

https://lh3.googleusercontent.com/-IQ9L1O1y_EY/UOPeKHa7s8I/AAAAAAAACUI/0ldI5DxZxSo/s400/IMG_20130102_020245.jpg

Benuser
01-02-2013, 09:34 AM
Thanks for the pix. A classic recurve belly after finger guard + steeling. Quite easy fix.

Lefty
01-02-2013, 11:12 AM
I've done a lot of these (just like lots of us here), and my advice is to also take the belly portio back by the same amoun as you need to get the finger guard to meet up with the bevel. In other words, if you have to remove 3mm of height from the guard, do the same to the rest of the edge.

Jmadams13
01-02-2013, 11:22 AM
I agree with lefty. If you don't bring down the belly, you risk loosing your flat spot at the heel and having it curve upwards. Mistake I've made the first few times.