Dremel bits for repairing and modifying knives.

[Perverockstar]

Hello, people. I have one knife that requires a tip repair and a couple of other ones that would benefit from rounding the spine.

My question is: which bits for a dremel or other rotary tool do you recommend for these tasks? Something that removes metal but it is not super aggresive. Maybe also something for smoothing out the work.

Thanks!

 

[MarcelNL]

Sandpaper in a couple of different grit sizes worked brilliantly for me rounding the spine of a knife, tip repair went pretty fast on a coarser stone (last time I used the 400 grit size of the 400/1000 diamond plate I use for flattening stones). Personally I'd stay away from the dremel as the bits are too small to create an even surface but there are others here with far more experience than me.

 

[Nemo]

You'd wanna be pretty careful not to overheat the steel.

 

[Benuser]

With carbons a nail file works fine to correct a tip. Automotive sandpaper for spine or choil. Stay away from the heel. No need for any powered equipment.

 

[ian]

It’s really hard to use a dremel to create convex surfaces like you’d want here, since typically the rotating thing will have a small circular cross section, so will create concavities on the blade. Use sandpaper on a flat surface or stones for the tip repair, and the same for spine rouding, supplemented with a shoe-shine motion. Or buy a belt sander.

 

[Perverockstar]

Noted. Any sandpaper grits and type you guys recommend?

 

[Rangen]

Noted. Any sandpaper grits and type you guys recommend?

I'll leave grits to others, because I have not done these things with sandpaper, and anyway it would probably depend on just how much metal you have to take off.

What I will say is that people who have used a lot of sandpaper seem to really like Klingspor. I had to order mine from overseas, but you will likely find it easier to get. I have not yet used it enough to judge it. What I've been mostly using is 3M Pro Grade/Precision/Cubitron II and Rhynowet, both of which seem excellent to me. I find that wetting the sandpaper a bit makes it perform better, and clog up more slowly, not to mention keeping down the metal dust in the air.

 

[tostadas]

120 grit is plenty coarse for the amount of work you're describing. Some may go down to 80, which is fine also. The easiest is to put the sandpaper on a hard flat surface, and treat it like a stone. For progression, at the minimum you should go 120-220-400. You can always go higher or lower if you like.

And to echo what others have said, a dremel may end up causing more harm than good for tip repair. It's easy to accidentally grind too much in one particular spot if you aren't careful with the small surface of the dremel tip.

 

[Perverockstar]

Do any of you recommend using stones instead? I was recommended the Nano Hone Diamond compound stone for thinning. I guess it could be used for that.

Any idea where I can get one here in the EU?

 

[tostadas]

Y

Do any of you recommend using stones instead? I was recommended the Nano Hone Diamond compound stone for thinning. I guess it could be used for that.

Any idea where I can get one here in the EU?

You can use stones. If you grind the spine like bread knife style on a stone, you may end up forming a groove in it, depending on the stone. I've done this kind of work with a Norton crystolon. It's cheap and it eats steel.

 

[ian]

I like using stones, personally, just because sandpaper on a flat surface can be kind of annoying. (That said, I really do all of this kind of stuff on a belt grinder.) A diamond plate or something is great, or just a low grit stone. Kinda depends on how much material we're talking about removing, though. If this is like a 5mm chip, I'd just find someone with a belt grinder. Some coarse stones are available here, or @tostadas's recommendation of a cheap oilstone would work.

https://www.cleancut.se/butik/knivslipning/slipsten-grov

 

[Perverockstar]

I like using stones, personally, just because sandpaper on a flat surface can be kind of annoying. (That said, I really do all of this kind of stuff on a belt grinder.) A diamond plate or something is great, or just a low grit stone. Kinda depends on how much material we're talking about removing, though. If this is like a 5mm chip, I'd just find someone with a belt grinder. Some coarse stones are available here, or @tostadas's recommendation of a cheap oilstone would work.

https://www.cleancut.se/butik/knivslipning/slipsten-grov

It is pretty much a 1mm broken tip on a Manaka ATS34 and a fat@$$ Shun Premier that is 10 years old and never has been thinned. I'm considering a Nano Hone 120.

 

[Grayswandir]

Hello, people. I have one knife that requires a tip repair and a couple of other ones that would benefit from rounding the spine.

My question is: which bits for a dremel or other rotary tool do you recommend for these tasks? Something that removes metal but it is not super aggresive. Maybe also something for smoothing out the work.

Thanks!

Tip repair should be done with a stone, not a dremel.

 

[Perverockstar]

Tip repair should be done with a stone, not a dremel.

Already went past that I'll get a stone.

 

[Grayswandir]

Already went past that I'll get a stone.

Sorry , I posted before reading the comments. I think you mentioned a nano hone or something like that? You can use rotary tools for certain tasks, but if you need precision, they can run away from you very easily and leave an uneven surface like others have mentioned. Good luck!

 

[Blank Blades.]

So for choils i use the little sanding drums that you put on the mandrels they sell. They work very well for rounding that area.

As for the spine or tip. Whetstone is the way to go imo. It you dont own a belt grinder.

I usually will do the polishing of spine on my stones even though i have a grinder though.

Sandpaper works, just use some kind of backing to avoid rounding too much and messing up then geometry near the spine.

 

[Perverockstar]

Well, some news to share. A co-worker lent me his 100 grit diamond plate. I fixed the tip of a Yanagiba quite easily. On the other hand, I tried thinning my Shun Premier, I spent around 20 mins on each side and it barely did a thing.

Any other suggestion?

 

[M1k3]

Well, some news to share. A co-worker lent me his 100 grit diamond plate. I fixed the tip of a Yanagiba quite easily. On the other hand, I tried thinning my Shun Premier, I spent around 20 mins on each side and it barely did a thing.

Any other suggestion?

Shun and Shapton Pro 120. Or coarse sandpaper.

 

[HumbleHomeCook]

A 100grit diamond plate should be quite aggressive.

 

[Perverockstar]

A 100grit diamond plate should be quite aggressive.

And it didn't thin the knife enough. It took a long time to get a decent result. The opposite with the tip repair, that one was done quick!