Another concave cutter via eBay

[Neli]

 

[Poink88]

Neli,

That is a bad tool. You need to grind the outer blade a lot...not an easy task especially since it is a curved (round edge) concave cutter. If you are here in the US, I can try to fix it for free and the shipping may be worth it but not from where you are.

You can use it for root work... and slowly fix it as you go by grinding only the outer edge of the outer blade and the inner edge of the inner blade. In time it will slowly improve.

 

[davetree]

BTW, the blade should not align just by a hair...literally. If the overlap is more then something is also wrong and need to be corrected. As I said, sometimes it is easy or could be hard.

Some Chinese made are "cheating" by adding a bevel at the outer side of the inner blade...this style is NOT ideal (though workable) as it causes a kick-back as you cut. Instead of it digging in like the outer blade would.

It appears that the Kaneshin tools have the same beveled edge as the Chinese who are cheating. You can see it clearly in the link you referenced on the pictures of their knuckle cutter.

 

[Poink88]

It appears that the Kaneshin tools have the same beveled edge as the Chinese who are cheating. You can see it clearly in the link you referenced on the pictures of their knuckle cutter.

You are right! Not good.

I guess faster production takes precedence. FYI, Ryuga, Tian, etc. do the same now even on their regular concave cutters. Believe me, it is a move for the worse performance wise BUT easier, maintenance wise.

Choose your poison.

 

[Dav4]

Fwiw, I hardly use concave cutters anymore. Branch removal for anything larger then 1 cm gets a saw. I mostly use a concave cutter to shape branch stubs before taking the Jin pliers to them.

 

[Neli]

I had a feeling it was not good.
I was thinking maybe to grind the center pivet (???) and try to put another one....or see at least what can be done.
I use my garden pruner for small branches now. Got it in Japan at bonsai outlet...so maybe it is for bonsai????

 

[Poink88]

Fwiw, I hardly use concave cutters anymore. Branch removal for anything larger then 1 cm gets a saw. I mostly use a concave cutter to shape branch stubs before taking the Jin pliers to them.

Whatever works best right?

I use mine even on 3" branches/trunks/roots. I do use the saw more on bigger sizes too but really depends on the situation. Saw is more jarring to the tree esp not too established ones (yeah I know...just wait LOL). Sometimes access is also a problem or it can damage close branches in tight quarters, etc.

 

[Poink88]

I was thinking maybe to grind the center pivet (???) and try to put another one....or see at least what can be done.

NO! You are kidding right?

 

[GrimLore]

I use a Fiskers Folding Tree Saw 99 percent of the time. I also use it for root reduction... My Wife buys me good tools and honest I rarely use them

Grimmy

 

[nathanbs]

I had a feeling it was not good.
I was thinking maybe to grind the center pivet (???) and try to put another one....or see at least what can be done.
I use my garden pruner for small branches now. Got it in Japan at bonsai outlet...so maybe it is for bonsai????

removing and replacing the rivet will not help your problem

 

[Poink88]

I was thinking maybe to grind the center pivet (???) and try to put another one....or see at least what can be done.

After giving this more thought, it is actually a good idea though very extensive and you have to know what you are doing.

1. Remove rivet,
2. Re-drill or grind the holes off center increasing diameter just a bit to reposition the center and effectively push the inner blade out.
3. Replace rivet with a bigger one to match the re-sized hole.

Too much work for a tool even for me.

 

[Neli]

So it stays in the pile of junk hen.

 

[Brian Van Fleet]

Sometimes a rivet gets bent, and at some point(s) in the rivet's rotation, the jaws meet better than others. Try to work the rivet around until you get a good contact between the jaws. Kathy worked on a pair of my concave cutters that had this problem. Once she got the cutters' jaw lined up by moving the rivet, she put it on an anvil and hammered the rivet trying to straighten it out. It did improve, but not completely.

 

[Neli]

Thanks Brian. I shall try that.