Chipper Knives

[RJ-Az]

We have two Vermeer disc chippers with feed rolls where I work. I am a mechanic for a highway dept. and do most of the knife changes on these machines.

My question is how often do any of you guys have to change knives. Operators say they cant feed or chip and the knives seem to be not real dull but I change em out and every things ok for several days of chippng then I have to do it again. We have our knives sharpened at the Vermeer dealer and they come back real sharp.

We also have an older Vermeer drum chipper that will chip a lot longer between PIA blade replacement. just thought I would see what others were doing on these machines

 

[Menchhofer]

Frequency of changing chipper knives depends on what you are chipping and what is being put in the chipper besides wood.

Knives can last for as long as a few weeks or as little as one day....or even a few hours.

The knives need to be replaced/sharpened when they begin to lose their edge.

For best results they should also be kept sharp both for the chipping aspect as well as less wear on the entire machine.

Hope this helps.

 

[RJ-Az]

We are running a lot of roadside brush and green and dry Mesquite through them. One crew boss and an inmate crew which I suspect like to throw a piece of tire tread in every so often as I have found evidence of rubber in the works. When the chipper is down they are picking up litter, I think I would rather chip brush than pick up litter but who knows what goes thru their heads.

 

[NeTree]

One thing that sends me absolutely foaming-at-the-mouth ballistic is groundies who put rakings into the chipper instead of in the truck. Those little tiny pebbles may not seem like much, but they'll wreck a set of blades faster than you can say "SNOT".

 

[MasterBlaster]

Yup, me too. I made sure I covered that in Excellent Groundman. Some fools don't realize that sharp blades make them (and the chipper) work less.

 

[Newfie]

Originally posted by netree
One thing that sends me absolutely foaming-at-the-mouth ballistic is groundies who put rakings into the chipper instead of in the truck.

Hmmm, you have a couple of groundies who I caught trying to do the same to my chipper. They only did it once.

 

[NeTree]

Good man, put some stank on 'em.


By the way, at least they've never chipped a grade 70 CHOKER, Mike...

 

[wiley_p]

Are you adjusting your bedknives when you repalce the cutting blades?

 

[a_lopa]

just got these blades supposed to have double the edge life,we will see

 

[NeTree]

Originally posted by wiley_p
Are you adjusting your bedknives when you repalce the cutting blades?

Nope. Not to say you shouldn't...


...but mine ain't going anywhere until I get the chance to hit it with a torch and a breaker-bar with about 5 feet of pipe on it.

 

[wiley_p]

I think its vital on drum chippers, havent maintained or used a disc enough to know for certain about their setup.

 

[NeTree]

Yep. But keeping the blades sharp is the real biggie!

Easiest way to accomplish that is to not try to chip rakings.

 

[Frans]

If the chipper is not sucking brush and the knives seem only slightly dulled then adjust the bed knife
Frans

 

[wiley_p]

Absolutely correct. Just having sharp knives isnt the whole solution.

 

[NeTree]

...but it don't hurt, neither. =)

 

[NeTree]

BTW...

RJ, in my experience, the Vermeer knives aren't the worst, so don't feel too bad.

15 minutes for the Vermeer 1250 versus 45 for the Altec.

...with air tools, of course.

What I've found helps: Spray the bolts and knives with dry-moly before re-assembly. I've never had anything loosen up thru use, but it helps to keep stuff from sticking when you take it back apart.

 

[Stumper]

I use anti-seize compound on the bolts. Slop it on good. Coat every bit of the threads inside and out. If properly torqued they won't loosen in use but you won't have to drill or torch them out for the next knife change.:angel:

 

[P_woozel]

I use anti-seize on every bolt over 3/8 in applications where its high torque and often removed. On the Conehead chippers a 5' breaker bar is part of the kit, knives are on at 360#

 

[Yellowdog]

I may not be the best example. I chip whole trees from mostly land clearing (sheared trees) so I get a lot of dirt and some rock sucked in. I check my knives before each 8 hour day, though, and use a knife sharpener to put a quick "little" edge on after a few hours of use when I feel the chipper is working hard.
I can tell by the sound the chipper makes whether or not it has sharp blades. Also, I don't adjust the bed knife. Tried once, after 2 hours under a BC2000, no luck. Took it to the dealer and they said it was fine and shouldn't need to be adjusted unless I use over sharpened blades and/or suck in something bad.

As far as the bolts go, anti seize is an excellent suggestion. I didn't try that, but instead use light oil. Does the anti seize allow bolts to get loose from vibration? Everything else on the chipper gets loose!

I am also a stickler for changing bolts out after 2 uses (flipping blades). It costs me more but the dealer recommends it and if you think about the forces those bolts are under, it isn't such a bad idea. Mine come out with a small cheater pipe as they are only torqued to about 210-215 ft.lbs.

I have also seen my blades last only a couple of hours but on other jobs last for a week. Mine are recommeded to be changed every 10 hours! Who has that kind of time? It takes a good hour to change a set to new knives and about 45 minutes to flip them.

Found it easier to buy new knives than send mine out to Vermeer who finally gave up the sharpening business down here. I guess they had too many complaints.

Menchoffer, I thought your sharpening was pretty good but I can't find decent boxes to ship them so I have 3 sets sitting around!

That's my 2 cents..

 

[Menchhofer]

Originally posted by Yellowdog [/i]

Menchoffer, I thought your sharpening was pretty good but I can't find decent boxes to ship them so I have 3 sets sitting around!
[/B][/QUOTE]


If you do find boxes to ship them just let me know. Would not mind sharpening for you again..