How much torque

Nick, it wouldn't be a bad idea to invest in a nice 3/4'' drive set.

I always clean the threads on the bolts with a steel brush and rag when we do a knife change. There is a lot of crud that builds up.
:thumbup: on the 3/4" drive set, sooo much easier changing out knives.
 
That all depends on what is going through the machine. If you have the other Nick working for you, then not very long at all. :-)

Its not just me, from groundie to management we treat our machines like crap. They never get greased and get sent out for weeks with alarm lights, malfunctions etc.

Its incredible really. I take care of my things, but whats the point of trying to take care of a machine that management wont fix even when its broke. They fix it eventually but not until it totally shuts down.
 
Agreed, hours matter less than material....but I probably change mine every 20-30 hours of operation on average.
 
30 hrs seems decent for a side to me. I can only get two sharpenings of my knives and be within the guidelines of minimum distance from bolt center to edge of knife. I was running them down further in the past until I measured. Never had any knife problems. I keep a sharp well adjusted anvil too. Nothing to checking and adjusting it on my machine.
 
A 1/2" breaker bar seems more apt than a 3/4" rachet set. I rarely use mine, although it's handy to have.


Then again, I rarely use a breaker bar... I figure that's why they have lifetime warranties on the ratchets! It's rare to blow one.
 
3/4 drive seems excessive to me-I've found 1/2 drive to be adequate for most things....not even a strain if you USE ANTI-SIEZE;)

(I do use a 1/2 inch drive breaker bar for some things)
 
Snap on's impact is worthy, although it's certainly not cheap.

Personally I don't mind breaking them loose nor doing the final torque, it's the 10-20 turns to get the bolts out that take so much time. I use my Mikita 1/2" cordless drill to spin bolts out after I break them.
 
A 1/2" breaker bar seems more apt than a 3/4" rachet set. I rarely use mine, although it's handy to have.


Then again, I rarely use a breaker bar... I figure that's why they have lifetime warranties on the ratchets! It's rare to blow one.
I have broken 1/2" Craftsman breaker bars and yes I use NAPA anti-sieze.
 
Now if you don't use some form of anti seize you might end up drilling the bolts out .Let me tell you drilling out a grade 8 cap screw is no easy chore .I've done several .Never Seeze is your friend .
 
  • Thread Starter Thread Starter
  • #38
So here's how it went down.

I bought a Kobalt brand torque wrench. It was $60 and did a fine job (or at least I think it did)

The bolts were different than what was shown in the chart...

ImageUploadedByTapatalk1378172244.067731.jpg

So I just made an executive decision and decided they were grade 8, fine thread.

Pulled the knives off, karina cleaned all the gunk off them and I reinstalled them.

Now that I have done it, I'm sure I can do the whole thing in less than an hour.

Can't wait. It's gonna be like getting a brand new chipper again! The knives were very, very dull and beat up.


love
nick
 
I was reading about the ir w7150. Looks nice. Reviews say can take tires off semi's. they get torqued 450-550 lbs. 5 bills though.
 
FWIW the actual holding ability of a threaded fastener ,bolt is akin to a spring under tension .In the simplest of terms a bolt is an inclined plane around a cylinder .Unless the fastener is rusted in tight once you relieve the torque on it it becomes easy to unscrew .For very little money you can buy an impact driver that will have the same effect as a pnuematic impact wrench .Fact I've broken stubborn fasteners loose with an impact driver I could not shake with a 1/2" Snap-on brand pnuematic impact wrench with 140 PSI air .
 
Nick, They are standard thread.....and I think that all of those hex drive bolts used on chippers are grade 5. While grade eight bolts are "stronger" they are also more brittle so grade 5 are very good in this type of application where repeated shocks and shear stresses are applied. No undue perspiration is necessary. They'll be fine thw way you torqued them.
 
If your knives are thrashed then good chance your bedknife/anvil looks the same. Flip it as well each knife change. They need to be sharpened and changed out as well for optimum performance.
 
Most times the bed knives get dished out in the middle .Depending but some times they can be refurbished by surface grinding .There should be specifactions as to how much clearance they should be between the knives and the bed. Be carefull now don't get a finger pinched because you could prune one right off on a chipper knife .
 
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