# Best edge for a beater knife?



## Michi (Mar 10, 2020)

I've just been given a knife by a friend to "resharpen". Its condition is such that, by the time I have new bevels established, the knife will be 0.5 mm narrower  It's unbelievable how people get their knives into such a state and then manage to cut with them regardless, sometimes for years…

Anyway, I've sharpened a whole bunch of other knives for that person (also in a very sorry state), and those knives are nice and sharp again. I recommended to have one knife as a beater knife that is used for the rough stuff. That way, the other knives stay in good condition and the beater knife takes all the abuse. The knife I'm about to start on is going to be the beater.

So, what's the best way to create an edge that will hold up to abuse as much as possible? The knife is going to be used a lot for cutting frozen fruit. Suggestions for angle? I'm thinking 20º, maybe more? Micro-bevel? If so, what angle for that? One side or both sides?

For what it's worth, the knife was originally purchased at Ikea about 30 years ago. Some kind of generic stainless steel; it says "Molybdenum/Vanadium, Made in Japan" on the blade.


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## aszma (Mar 10, 2020)

I mean if the primary use is frozen fruit and he bought it from ikea wouldnt it just be a good idea to save everyone time and buy a new 5 dollar knife from ikea instead of trynna fix a 30 year old beaten knife?


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## Michi (Mar 10, 2020)

aszma said:


> wouldnt it just be a good idea to save everyone time and buy a new 5 dollar knife from ikea instead of trynna fix a 30 year old beaten knife?


That’s exactly what I suggested, too. But it’s an emotional thing; there are memories attached to that knife…


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## Midsummer (Mar 10, 2020)

22 degrees is standard for good german/ french /english steel. My bench chisels go at 35 degrees. I think I would aim for a bench chisel grind.


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## Michi (Mar 10, 2020)

Midsummer said:


> I think I would aim for a bench chisel grind.


How does that work? I honestly have no idea.


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## LostHighway (Mar 10, 2020)

Michi said:


> That’s exactly what I suggested, too. But it’s an emotional thing; there are memories attached to that knife…



They must be bad memories if they are using it to cut frozen fruit.


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## ian (Mar 10, 2020)

Michi said:


> How does that work? I honestly have no idea.



Think he’s just saying make it a big angle, like 35 degrees. Doubt he’s suggesting you transform it into a single bevel.

I’d agree with a fat bevel. Just do a 30 degree angle each side and be done with it.


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## Midsummer (Mar 10, 2020)

Michi said:


> How does that work? I honestly have no idea.



I am far from the best sharpener and actually a double bevel knife sharpened to 15 degrees a side would have a 30 degree inclusive bevel. My chisels are single bevel. But I guess my point is that when working with delicate woods you can have a smaller bevel and it is easier to work. With harder woods and more abuse you want a heftier bevel.

So I would angle the spine to the plane of the sharpening surface to about 30-35 degrees (probably 30 as it a third of 90 degrees) and grind on a 500(or longer on a 1000). Once apexed, do the same on the other. It can be surprisingly sharp. It just does not enter food easily. Does that make sense?


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## kayman67 (Mar 10, 2020)

Convex, high angle, 25-30°. If the overall geometry is suited for such construction. In theory this should be able to survive hammering bones and cut decently enough.


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## M1k3 (Mar 10, 2020)

20-25° or so. Around 500-1k grit finish.

A meat cleaver is nice for frozen stuff. Kiwi makes an inexpensive, durable one.


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## daveb (Mar 10, 2020)

Fat angle, coarse stone.

Having done a few years in Uncle Sam's Navy I liken the knife blade to the bow of a ship. On a ship that's designed to cut through the water with ease, the bow will be narrow and longish. You're trying to make an icebreaker. Blunt short bow for solid strength. No reason to polish the edge.


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## Cloudsmoker (Mar 10, 2020)

I love my old meat cleaver. And I use it for all sorts of things I’m not likely to confess to.


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## panda (Mar 10, 2020)

30 deg per side. 320 grit edge.


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## Michi (Mar 11, 2020)

Thanks for all the tips, I much appreciate it!

I think I'll try with 25-30 degrees and convex the bevels a bit. It should still be sharp, and have a bit more meat behind the edge that way.


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## Benuser (Mar 11, 2020)

I'd start with automotive sandpaper, P240, with a rubber or soft wooden backing, edge trailing only to avoid overgrinding. Gives a nice convex bevel in line with the face. From there on cleaning up by edge trailing 'stropping' and deburring on a medium stone. I go directly to a Chosera 800. If it is the equivalent of Krupp's 4116 you may stop, otherwise just light further deburring on a 2k or what you have.


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## vicv (Mar 11, 2020)

I agree with @Benuser, that is how I would do it if I didn't have my belt grinder. for those type of knives I do use lion and I basically lay the knife flat on the slack portion of the belt with moderate pressure at the edge. This gives a low angle but high roundedness convex edge which is very sharp and holds up very well to the type of use that you are implying this knife will see. The same type of edge can still be made with sandpaper with a soft backing it will just take much much longer


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## Michi (Mar 11, 2020)

Thanks @Benuser and @vicv. I can see how the soft-backing sandpaper idea will help to convex the bevels. I was thinking of using my 320 Cerax and Carter's rocking technique to make a convex bevel. But the sandpaper thing might actually be easier. I have some firm polyurethane mats around that probably would be just right for this.

I'll tackle this over the weekend. Plenty of P240 sandpaper around here anyway


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## kayman67 (Mar 11, 2020)

It's perfectly doable with stones, but if you never did it before, takes a bit. So use what feels easier.


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## dough (Mar 11, 2020)

I been down this road too many times “helping” friends save whatever knife and I like a clamshell shaped edge.
I see that’s what is currently being discussed. It’s called hamaguri in Japanese but that and thining the blade road/refinishing the knife is usually my move. Sure it’s too much work but I only do it for people that love their things.


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## Michi (Mar 14, 2020)

So, I had a go at this thing. And, man, it's killing me…

The knife had really deep chips and was in terrible shape (including about 5 mm missing at the tip because someone dropped it on the floor years ago). So, I took my Cerax 320 and went to work at 30º, figuring the first order of the day would be to establish new bevels before I worry about anything else.

So, I sharpen away and, man, it's painful. Multiple passes (as in ten or more each side) before I finally got all the chips out and the edge was clean. I checked with a loupe, and I got very nice clean bevels established, maybe just under 1 mm in width, without any faceting and a very even scratch pattern.

So, I figured I'll keep going until I raise a burr. Now, normally, with the Cerax 320, I get a _monster_ burr in one or two passes, even with German stainless steel, such as on a Wüsthof or Victorinox. With this thing, no joy. I kept trying and trying. I could see that steel was coming off from the swarf on the stone, but no burr. Multiple attempts over maybe two hours, going really hard on one side, then really hard on the other side, no luck. Going lightly, no luck. Alternating sides, no luck. I cannot feel a burr, no matter what I do.

In the end, I gave up in disgust, changed to deburring strokes (edge leading) with light pressure, and tried the knife. It cut like crap. Tried again after some more edge trailing strokes. Same result.

In the end, I figured "OK, let's see what happens if I hone with a diamond steel." I got something resembling a toothy edge that sort of cut, but not well. Back to the drawing board…

Trying with my Cerax 1000 this time. Definitely removing metal, lots of swarf on the stone. Looking at the bevels with a 20x loupe, I can see that the bevels are perfect, very even scratch pattern. But no burr. Try to cut something again, and it's not much better.

OK, let's see what happens with green compound on the suede side of leather. Only marginal improvement.

In the end, I used the diamond hone again, followed by a normal steel hone, and managed to get something that cuts, but poorly. It'll cut paper OK (but loudly) along the grain, and reluctantly (and noisily) across the grain.

I don't know what is happening here, but I'm fairly sure it's not me. I just sharpened three knives I received from the same person, in equally terrible shape (two Victorinox and one Elite). Those are made from X50CrMo14, and I had no problems at all. Razor-sharp once I was done.

But this thing left me defeated


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## KingShapton (Mar 14, 2020)

Sounds like wasting your time. Some cheap knives are crap and stay crap, no matter what you do


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## Michi (Mar 14, 2020)

KingShapton said:


> Sounds like wasting your time. Some cheap knives are crap and stay crap, no matter what you do


Not the answer I wanted to hear, but I suspect you are right.

I was dreaming of returning that knife to razor sharpness. Now I have to deal with all my shattered illusions instead. It will take weeks…


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## Midsummer (Mar 14, 2020)

For cutting frozen food, it seems perfect. I have a 45 year old Henkle stainless slicer that I can not get a burr to form. I keep it to remind me of my limits.

Really nice of you to help your friends. They will be pleased. If they are anything like the people I sharpen for, they will be using the dullest knife the most. Folks seem to be afraid of the sharp knife.


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## madelinez (Mar 14, 2020)

I experienced something similar recently with a Chinese clone of a Wusthof, I just couldn't make it sharp. I spent a couple of weeks trying but barely got it past tearing paper.


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## KingShapton (Mar 14, 2020)

Michi said:


> Not the answer I wanted to hear, but I suspect you are right.
> 
> I was dreaming of returning that knife to razor sharpness. Now I have to deal with all my shattered illusions instead. It will take weeks…


I know very well how something like that can get frustrating.

I myself have spent countless hours in vain repairing and sharpening cheap or very cheap knives from friends and my mother-in-law.

In the end, I had to see with some knives that I wasted my time. It was even more difficult to explain to the owners why it cannot be sharpened and why it is not worth it.

I have learned from this before I promise to sharpen his knife, I want to know what it is and prefer to see it beforehand.

So I avoid disappointment and frustration on both sides.


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## Michi (Mar 14, 2020)

KingShapton said:


> I have learned from this before I promise to sharpen his knife, I want to know what it is and prefer to see it beforehand.


Smart move!

My ego just took a big dent. I thought that I could sharpen anything with enough determination and patience. Not so…

At least I can feel good about it in the sense that I think I can safely blame the steel. This is the first time after probably 200 or so sharpening sessions that I didn't get something really sharp.

I don't know what steel they used for that thing. It's quite bendy for its thickness, much more so than a Victorinox, which has a blade of about the same thickness. They probably melted down a bunch of recycled fruit tins or some such…


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## kayman67 (Mar 14, 2020)

Usually I manage to get knives like this sharp, using coarse diamond plates or SiC stones. If you have any, give them a try.

Sharp doesn't guarantee retention for that usage scenario, though. I would also test the edge a bit. See just how soft the alloys is.

If you get these from a couple of known low HRC knives while hitting your edge, things won't be pretty.


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## Michi (Mar 14, 2020)

kayman67 said:


> If you get these from a couple of known low HRC knives while hitting your edge, things won't be pretty.


Ouch, that looks terrible!

Thanks for the tip on the SiC stones. But I don't think I'll go and buy an $80 stone in order to try and rescue a garbage knife that is worth $10, if that.

I think I'm done with that knife. It cuts passably well–I just cooked dinner with it, going through some considerably traumatic moments—and I've decided that "you _thing_, I'm _done_ with you!"

Enough is enough.


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## vicv (Mar 14, 2020)

Good idea it is time to give up. One day you should get yourself a belt grinder just for this type of work. They are very handy


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## ACHiPo (Mar 14, 2020)

Michi said:


> Not the answer I wanted to hear, but I suspect you are right.
> 
> I was dreaming of returning that knife to razor sharpness. Now I have to deal with all my shattered illusions instead. It will take weeks…


Maybe it’s time for you to pick up a belt grinder?


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## Benuser (Mar 14, 2020)

kayman67 said:


> Usually I manage to get knives like this sharp, using coarse diamond plates or SiC stones. If you have any, give them a try.
> 
> Sharp doesn't guarantee retention for that usage scenario, though. I would also test the edge a bit. See just how soft the alloys is.
> 
> ...


Nice photo... 
Carbide clusters falling out??


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## kayman67 (Mar 14, 2020)

I'm not sure. It's interesting how different knives made different "cuts".


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## Desert Rat (Mar 14, 2020)

I deal with those kind of knifes on a old Norton 313 with two crystolon stones and a fine india. I just raise the blade a few degrees at each stone progression approximating a convex bevel. If I am looking for a really toothy edge on a carbon steel knife a fine India works well.


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## Michi (Mar 14, 2020)

ACHiPo said:


> Maybe it’s time for you to pick up a belt grinder?


Would a belt grinder get the knife sharper? Or would it just make me give up in disgust earlier?


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## M1k3 (Mar 14, 2020)

Drop down


Michi said:


> Would a belt grind get the knife sharper? Or would it just make me give up in disgust earlier?



Might retemper it... Or option 2.


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## Cloudsmoker (Mar 14, 2020)

ACHiPo said:


> Maybe it’s time for you to pick up a belt grinder?


You know, I was about to say that. I worked on a couple of beaters about the same look and vintage. My guess was that years of cleaning in the dishwasher was to blame (not sure why, but I was looking for something to blame besides my limited sharpening skills). Finally, I gave the belt sander a try, with a 320 grit belt, and the beater blade sharpened right up - at least for a few strokes. I would never have admitted any of this except for Michi confessing first.


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## Michi (Mar 15, 2020)

Cloudsmoker said:


> I would never have admitted any of this except for Michi confessing first.


It’s alright, you can trust us around here, we won’t tell. Besides, we all have our dark little secrets. (I used an oilstone once.)

As penance, all you need to do is sharpen five proper knives on stones, and the blemish of the beater and the belt sander will be washed away.


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## M1k3 (Mar 15, 2020)

Michi said:


> (I used an oilstone once.)



I've used more than one, more than once, in the past week.

What's my penance?

I will use them again though, so...

(In my defense, I don't own them. They belong to my works owner, so they are accessible to everyone)


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## Michi (Mar 15, 2020)

M1k3 said:


> What's my penance?


Thirteen Globals, five Dalstrongs, and one Forged in Fire, 30 minutes each. That should do it.


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## M1k3 (Mar 15, 2020)

Michi said:


> Thirteen Globals, five Dalstrongs, and one Forged in Fire, 30 minutes each. That should do it.



Ugh. How about thinning/sharpening a Shun Ken Onion, 2 Wusthof Pro's, a Wusthof Ikon Nakiri, a Kiwi or two and whatever house knives are around (I think somewhere around 7-10?)


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## M1k3 (Mar 15, 2020)

Otherwise I have to buy some crap knives....


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## Michi (Mar 15, 2020)

M1k3 said:


> Ugh. How about thinning/sharpening a Shun Ken Onion, 2 Wusthof Pro's, a Wusthof Ikon Nakiri, a Kiwi or two and whatever house knives are around (I think somewhere around 7-10?)


I do believe that this would constitute sufficient penance


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## Benuser (Mar 15, 2020)

Michi said:


> Thirteen Globals, five Dalstrongs, and one Forged in Fire, 30 minutes each. That should do it.


I miss the Kai Wasabi.


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## RDalman (Mar 15, 2020)

I will agree with the belt grinder for beater edges. I run them on slack and raise and flip a burr on 60 grit. Flip it again couple of times on 240 grit, then deburr it on a polishing wax loaded felt wheel.


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## Michi (Mar 15, 2020)

RDalman said:


> I will agree with the belt grinder for beater edges. I run them on slack and raise and flip a burr on 60 grit. Flip it again couple of times on 240 grit, then deburr it on a polishing wax loaded felt wheel.


If I read this correctly, you are telling me that it's actually possible to get one of these abominations sharp that way?

If so, I'd actually consider buying a belt grinder. Any suggestions as to what model? (Casual domestic use.)

Edited to add:

60 grit on a kitchen knife? Please, don't do that to me again. I'm getting old, and there is only so much my poor ageing heart can take…


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## RDalman (Mar 15, 2020)

Michi said:


> If I read this correctly, you are telling me that it's actually possible to get one of these abominations sharp that way?
> 
> If so, I'd actually consider buying a belt grinder. Any suggestions as to what model? (Casual domestic use.)
> 
> ...


Hahaha Yes I have yet to be stumped actually this way.


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## vicv (Mar 15, 2020)

60 grit is fine. You're removing metal to remove chips and a thick edge. You want as course of a belt as you can find. They grind faster and cooler. 36 grit is even better!


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## Midsummer (Mar 15, 2020)

vicv said:


> 60 grit is fine. You're removing metal to remove chips and a thick edge. You want as course of a belt as you can find. They grind faster and cooler. 36 grit is even better!



So he can get it sharp with the grinder. But, we are missing 1/2 of the equation. The knife is going to be used to cut frozen food. (see OP)


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## Cloudsmoker (Mar 15, 2020)

As for belt sanders, I already had one I use for woodworking. But, if I were in the market, I'd look hard at this one: Ricoh 1x30 variable speed. The 1x30 belts are fairly inexpensive, plentiful and available in every grit and material, including leather strops. The variable speed is a feature that would be worthwhile as well. Some guys turn these into a knife sharpening machine -


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## Nemo (Mar 15, 2020)

You should put an edge on it that will put holes in your tea towels ;-)


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## Desert Rat (Mar 16, 2020)

Nemo said:


> You should put an edge on it that will put holes in your tea towels ;-)


Funny you should mention that. A recent development in our home are her very own tea towels that I am not suppose to use.


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## Nemo (Mar 16, 2020)

Desert Rat said:


> Funny you should mention that. A recent development in our home are her very own tea towels that I am not suppose to use.


This was a quip about Michi's tea-towel thread.


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## Benuser (Mar 16, 2020)

Desert Rat said:


> Funny you should mention that. A recent development in our home are her very own tea towels that I am not suppose to use.


Rebellion!


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## Marek07 (Mar 16, 2020)

Michi said:


> For what it's worth, the knife was originally purchased at Ikea about 30 years ago. Some kind of generic stainless steel; it says "Molybdenum/Vanadium, Made in Japan" on the blade.


The current range of Ikea 365+ knives are by no means stellar - but they are fairly easy to sharpen and represent good value for many IMO. Have often gifted them to friends - mainly Kiwi users (see below).


vicv said:


> Good idea it is time to give up. One day you should get yourself a belt grinder just for this type of work. They are very handy





ACHiPo said:


> Maybe it’s time for you to pick up a belt grinder?


A cheap belt grinder is a welcome addition to one's armoury. After spending 45 min sharpening a very abused Kiwi, I thought Wt*?!? Why spend so much time on a $3 knife. Just buy a new one. Or... 1 min on a belt plus a couple of minutes on a stone and presto - mission accomplished.


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## Michi (Mar 17, 2020)

Marek07 said:


> Why spend so much time on a $3 knife. Just buy a new one. Or... 1 min on a belt plus a couple of minutes on a stone and presto - mission accomplished.


I like your approach! I mean, why spend $3 on a new knife when I can spend $165 on a new belt sander?


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## Marek07 (Mar 17, 2020)

Michi said:


> I like your approach! I mean, why spend $3 on a new knife when I can spend $165 on a new belt sander?


My basic belt sander cost $65. Divide that by a few dozen Kiwis and assorted crap knives and it becomes very cost efficient. Regardless, I don't charge for sharpening - just enjoy the challenge.


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## Michi (Mar 17, 2020)

Marek07 said:


> My basic belt sander cost $65.


What make/model are you using?


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## Benuser (Mar 17, 2020)

Had to repair Tojiro DP Honesuki and Yo-deba, VG-10 core. Did it with coarse stones, GS 120, 220, 320. Lot of work. Wasn't that satisfied with result. Some facetting. Started again with somewhat worn P240. Medium pressure, edge trailing, on dominant side only. Less than 10 strokes needed. Went after that on Chosera 400. Give it a try.


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## Michi (Mar 17, 2020)

Benuser said:


> Started again with somewhat worn P240. Medium pressure, edge trailing, on dominant side only. Less than 10 strokes needed. Went after that on Chosera 400. Give it a try.


Thanks for the tip! I had a look at belt sanders, and I don't want to do it to myself. It would get used maybe once a year, and would end up being yet another piece of gear to clutter up the workshop.

P240 takes up a lot less room and is dirt-cheap, so that'll be my choice next time. For now, the knife is cutting well enough. And I hate the dang thing sufficiently by now that I don't want to go back and start again.

On the up-side, my ego is on the road to recovery…


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## ITKKF (Mar 17, 2020)

Did you sand the handle and oil it? I think this will compensate a bit for the not so perfect edge.

Cheers!


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## Michi (Mar 17, 2020)

ITKKF said:


> Did you sand the handle and oil it? I think this will compensate a bit for the not so perfect edge.


That's absolutely brilliant, I love it!
_
"This knife cuts like crap. But man, that handle! I could fondle it all day long…"_


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## Marek07 (Mar 17, 2020)

Michi said:


> What make/model are you using?


A Ryobi 370W Belt and Disc Sander. However I'm embarrassed. Just had a look and it now costs $106. I *thought *I bought mine for $65 two years back. Don't think it would have gone up that much... perhaps it was but most likely my brain cells have failed me and it was closer to $85 at the time. Sorry if I've misled. (using USD for the forum)


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## Michi (Mar 17, 2020)

Marek07 said:


> Sorry if I've misled. (using USD for the forum)


Not a problem! I'd pretty much decided already that, for now, I'm going to give the belt sander a miss anyway. It's not a matter of cost, but that I simply don't want yet another almost-never-used piece of big and heavy machinery cluttering up my workshop.


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## Cloudsmoker (Mar 17, 2020)

Marek07 said:


> A Ryobi 370W Belt and Disc Sander. However I'm embarrassed. Just had a look and it now costs $106. I *thought *I bought mine for $65 two years back. Don't think it would have gone up that much... perhaps it was but most likely my brain cells have failed me and it was closer to $85 at the time. Sorry if I've misled. (using USD for the forum)
> 
> View attachment 74234


I have the Wren (orange) model of that, too. The Wren’s tend to run about 20% cheaper and, according to Amazon reviewers who claim to know, is the exact same unit with different paint. I’ve abused the crap out of mine and it refuses to die.


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