Sharpening Chipper Blades

[SkiTown]

I tried a search, but didn't find what I was looking for.

Who's sharpening their own chipper blades and how are you doing it? I haven't found a reliable sharpening service where I live and the one guy who was doing it just quit. I know that some of you would rather buy new sets than sharpen, but that doesn't work for me. My chipper is a Vermeer 1230.

Thanks for the input.

 

[CoreyTMorine]

Baileys sells a sharpening dohicky for ~$12usd it works ok, it definatly gets me more time between sharpenings. And i think that bandit has a mail in sharpening service.

 

[Timberhauler]

I have an uncle that has a machine shop,he keeps my knives sharpened for me,He's also built a couple of dump truck beds for me...I only sharpen mine twice before I replace them.

 

[Rftreeman]

I have touched mine up with an angle grinder to get me trough a few weeks till I could get them done at the machine shop.

 

[John Paul Sanborn]

Baileys sells a sharpening dohicky for ~$12usd

That is a gread dimond stone in a jig for regular field honing.

I have friends that use the angle grinder for touchup on a regular basis. You just cannot take too much oof any one side or you will unbalance.

There is a new oil bath grinding set on the market for ~1400. You mount the knife on the rail and crank it past the slow stone on a rail. Macheshop quality from what I hear.

Just found the website

http://www.chipperknifesharpener.com/

 

[okietreedude1]

JP,

thats pretty cool. Not sure its worth the 1400 price tag (thats a lot of shapening).

Anyone have one ore know of someone that does????

 

[Stumper]

I sharpen mine on a moderately slow bench grinder. Since I am using the perimeter of a round wheel the natural result is a hollow ground edge. I prefer to do a double hollow grind in order to maintain a strong edge without resorting to either a weak full hollow or a rather blunt small hollow edge on top of the original angle.

 

[John Paul Sanborn]

JP,

thats pretty cool. Not sure its worth the 1400 price tag (thats a lot of shapening).

Anyone have one ore know of someone that does????

I guess it depends on how big your chipper is and how often you take them off.

This guy has an 18 & 22 inch chippers, both have knives on the disk. He keeps like 3 or 4 sets so he can do them all at once on the grinder in a short period of time.

 

[Tree Machine]

I sharpen mine once or twice a week. I have a small (6") chipper, so sharp knives are critical to getting the most out of the little unit.

I sharpen like Stumper says, a slight curvature on the bevel side alongside the edge. The pic here shows the grinder wheel on the other side, which I do on the final pass, just to knock the burr off.

This is an old picture. These days I use a grinding wheel that is worn down small, past the half way point of it's life. The smaller diameter wheel allows a little better control. You need a pretty steady hand because a slip can screw up your sharpening job.

I wear welding gloves and one of those clear, plastic face shields and ear plugs. It can be dangerous, don't take it lightly. Protect yourself.

I keep three sets of knives and get about six months per set before I feel the performance diminish, even after a razor-sharp sharpening (increased gap between the knife and anvil, I suppose). Then goes on a new set. After another six months or so, the third set goes on and the previous two sets goes in for professional sharpening. At this point I have three fresh sets and in another six months, off comes set #3 and on goes one of the freshly sharpened set. At this point the anvil gets adjusted and the whole cycle repeats.

I've never taken them off to sharpen them, but that's because if I take them off, there's a fresh set to go on. I think it would be easier to sharpen them off the disc, but I'm sorta lazy that way, sharpening them while on is quick, under 5 minutes for the three knives, and I always get a good result.

 

[Tree Machine]

I use these doohickey sharpeners only after the knife has a good sharp edge, then this thing brings it up to A+. To use these things on dull knives with the thought of making them sharp is a pointless effort in futility, though I encourage you to try it for yourself and make your own determination. It might help somewhat, but on dull knives you just gotta pull some metal off and recreate a righteous edge.

 

[a_lopa]

A bench belt sander for a few sharpens then get them done at the shop.

 

[hornett22]

when you shrpen you shorten.

i assume you are adjusting the knife bed?

 

[a_lopa]

T/M i cant believe you use an angle grinder! An air ratchet takes the pain out of unbolting the knives.

 

[Tree Machine]

T/M i cant believe you use an angle grinder! An air ratchet takes the pain out of unbolting the knives.

I have air ratchets, impact wrenches and such. Each knife has three bolts, so nine bolts off + 9 bolts back on equals 18 bolts to deal with. In the time it takes just to get them on and off I can already have them sharpened. You just make light passes so you don't heat up the edge. I make about three identical passes per knife, from bottom to top, at about ten seconds per pass, then knock the bur off with a light pass to the other side, then a few pulls with the knife saver device.

What's so hard to believe? Been doing it for years.

i assume you are adjusting the knife bed?

Nope. I take so little off the knife's edge there is very little difference in tolerance from sharpening to sharpening. When the gap between anvil and knife opens up a couple millimeters, you feel it in the performance, the chips get bigger, engine dogs a bit more quickly. That's when I pull the nine bolts, flip the knives (dual-edged) and replace the nine bolts. The gap is again perfect and I sharpen them about weekly again until I feel the knives shorten a couple millimeters, then I pull them and put on a new set.

You can see with three sets of dual-edged knives, you can stay perpetually sharp, well adjusted and really with a minimal of effort.

Now, my knives are very easy to get at and work on. This won't be the case on all chippers. My Dad's 4" Gravely chipper, there's no way to do this. We pull those off and do them like Aussie Lopa, but with a handheld belt sander turned upside-down.