Questions on thinning/grinding

So, I'm basically in the process of sorting through my knives; buying some, selling others, messing about with the others that I can't do much with, etc.. During the process there has been two instances where I've thought "boy, it'd be good to have some sort of grinder right now instead of this worn DMT XXC". The first instances would be with two knives in my current kit which have overgrinds (1 anyway, I'm not 100% sure about the other). The first being my mizuno usuba, I think I've actually got the blade flat again but it's basically too thick behind the edge now to be good for anything other than peeling. I've put it to the stones a few times, but it's just such a bloody choir :surrendar:. The other which I'm not 100% sure about, is my sugimoto #6. I was actually gonna list this on the BST forum, but while going over all and touching up the knives I was planning to list a very slight wave in the edge came up. I tried measuring the thickness with calipers, I'm pretty sure it is slightly thinning in the middle just above the edge but I only have analog calipers to I can't be too accurate. Quite disheartened by the sugimoto, cause I love the knife and I've always been chuffed with their products. Still an awesome knife, so i'll probably just hang on to it and put in the time to fix it up.

The second thought which prompted the inquiry is that I'm starting to use my sabatiers again and looking to the future when I've sharpened them down and need to grind down the bolster, I thought it'd be handy to have a grinder of some sort.

So basically, I'm keen to get some advice on whether people: would recommend I pick up a grinder; can you even get a cheap grinder; does it need to be a belt grinder or do those benchtop disc grinders work or; should I just man up, hit the stones and deal with tendonitis. Or if it's even appropriate for a lesser experienced person to put their knives on such devices, would I likely cause more damage?

Cheers in advance,
Josh

i am very interested in the answers you get, because i've also been thinking about getting a grinder.

IMHO do it.

If you never worked with belt sander, there is risk you will mess up sugimoto more. But if you pay carefull atention you should be good.

For sabatier I wouldnt bother to buy a grinder just for that purpose.

I myself bought cheap SKIL from their pro series, it gets simple jobs done.

For grinding away a finger guard, thinning and changes in geometry I use sandpaper in the P120-600 range. Much faster than stones, without the risks of a grinder.

As to the Sab's, I saw a thread (I believe it was in Dave M's vendor section) where he had done very nice work on the bolster...in fact I believe mine will be headed there for the same spa treatment.

I'd recommend getting a cheap a$$ grinder. I got a 1x30 from Harbor Freight. I honestly never thought it would make it this far but it has. Make sure you get some good belts. They make all the difference. I'd also get a few dead, cheapo knives that you can practice on. There is a bit of a learning curve to do really nice work. FYI, I've been told that basically the same grinder from ENCO would be a better buy.

tk59 said:

I'd recommend getting a cheap a$$ grinder. I got a 1x30 from Harbor Freight. I honestly never thought it would make it this far but it has.

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Yip, this one gets brought up time and again.
Think there are even some tutorials on modding these things a bit for better performance.

The CCK cleaver of grinders...

I own a belt grinder 42 inch with option to use either a 1inch or 2 inch belt.
I rarely used this machine as I do not like the idea of iron dusts floating in the air. Only use it when I need to seriously grind away metal when there is a serious chip or ding. IF it is just nicks.. I still use the stone.

AS a system to sharpen knives which already has a secondary bevel.. it is not my preferred system at all. Rounding off : hanging” bolster of german knives.. is fast. No tip work as it is too fast and not to mention the heat and sparks.

I also own a 3 other machines.. a)Tormek system.. again it is hardly used except to reshape the tip or correct a profile. It is kinder as it is water based. As a sharpening system.. not my cup of tea as it leaves a hollow grind b) A flat type circular diamond disk c) A F Dick system

So basically , after playing with these tools.. I have gone back to being a stone man.%2pI have come full circle.. The tools are still being used.. rarely that’s all fro reprofiling and repair work that’s all and if having a reasonably priced belt sander makes you happy even if you use it once a year.. by all means do it! I have a tools that I rarely used. But each time they are used.. it is satisfying..
SO enjoy grinding the bolsters when the time comes…

Have fun,,

rgds
david

Oh I've been here before!

FWIW, I've MADE a knife on a HF 1x30 with AlOx belts and no respirator. I heartily do NOT recommend it.

First off, the overgrinds--you will only make those worse on a grinder unless you have a goodly amount of experience. Especially on a 1x30, you will burn in that overgrind so big you'll want to throw the knife away.

If you don't get good belts(I use TruGrit for those, you can get Norton Blaze belts for a 1x30 there, which is hilarious and awesome), the belts you can get at HF for it are just going to do a great job of warming your knife up for you. The real trouble with a grinder is not the speed of steel removal. It's the heat buildup. You put the tip of a Sabatier on a belt(even a good one) when you are thinning it and leave it there for 5 seconds and it's blue as a jaybird. No problem though, cause you can just flick the tip off with your finger at that point.

Assuming you are careful about heat, a HF 1x30 for grinding like this(I.E. not wood, or sharpening) is a little rinky-dink motor, and when you put any more than about a 1/2" of metal up against the belt, the belt is either going to skid along the surface just scuffing it, or you press and it's going to go "wub wub wuuub wuuuub wuuuuuuuuuuuuh" and stop. It takes little to stop it.

It is great for taking down fingerguards. It is great for sharpening cheapo steel. It is great for other little projects, including handle wood work. Only recently have I started to prefer my 2x42 over my 1x30 when doing careful restoration work, rounding spines, etc.

If you feel like having one, get it. It's cheap, though it's not just $40...you gotta add in the cost of good belts and maybe a leather strop, eye protection(don't kid yourself), maybe some stuff to mount it on it's back, some way to clean up all the dust. It will also require learning a new skillset, and I would strongly agree with TK that you should practice on several other knives before you touch anything you care about to it.

If you just want to fix your knives, it's probably most economical to put in the time on the stones/plates. I mean, yeah, it's work, but once you are done, you are done, and you can, in the process, reset the fingerguard so that it matches the sharpening angle and moves down with subsequent sharpenings. You can also sharpen knives with little overgrinds on a plate/stone, provided they aren't overgrinds from a 48" radius wheel. Plus, muscle memory(the Wheaties defense).

If your time is too valuable for that, and the belt grinder sounds like a hassle or not your bag, send it out to have it done.

BurkeCutlery said:

...Assuming you are careful about heat, a HF 1x30 for grinding like this(I.E. not wood, or sharpening) is a little rinky-dink motor, and when you put any more than about a 1/2" of metal up against the belt, the belt is either going to skid along the surface just scuffing it, or you press and it's going to go "wub wub wuuub wuuuub wuuuuuuuuuuuuh" and stop. It takes little to stop it...

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Don't insult my baby! Okay. It really is a dinky motor and you really can stop it and it does just scuff if you put a large surface up against the platen but it's not THAT bad, assuming you're not in a big hurry. I've made several knives on mine including a huge suji made of top notch steel at 62 hrc.

BurkeCutlery said:

Assuming you are careful about heat, a HF 1x30 for grinding like this(I.E. not wood, or sharpening) is a little rinky-dink motor, and when you put any more than about a 1/2" of metal up against the belt, the belt is either going to skid along the surface just scuffing it, or you press and it's going to go "wub wub wuuub wuuuub wuuuuuuuuuuuuh" and stop. It takes little to stop it.

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:rofl2::rofl2: I have brought my 2hp to a dead stop many a times,I can't imagine using a "wub wub wub wuber". Also please wear a respirator and glasses,don't prove Darwin wrong.

Dude, that was me being dumb for a day, I has no idea how much dust there would be. I wheezed for 3 days, for real. I got a one time use respirator from hatbor freight the next day.

Nowadays, I have good safety goggles and a 3m respirator on, even for woodworking. I want to buy things from people that take care of their workers and selves, so I work accordingly. I've gotten to where I prefer the smell of filtered air, lol.

Thanks for the advice so far everyone. It's sounding more and more tempting to pick one up, even if it's just for the experience. Should be educational. I'll try and swing round to Bunnings and see if they've got anything cheap and cheerful in stock.

My partner rolls her eyes at me enough, what with frequent delivery vans showing up at the door, wonder what she'll say if I come home with a belt sander