wide head mill band life?

[caveman]

For those of you who have been running the wide head mills who have previously owned the standard mills, do you notice any difference in board footage sawn between sharpenings or number of sharpenings per band?  I was thinking you may get a little more bf since there are more teeth on the band.

[offrink]

If you cut the same size pieces then yes you should get more. But if you have the wide you usually are going to take advantage of it and have wider logs. 

[Crossroads]

I haven't really noticed a difference, but it's hard to compare since I pressure washed pretty much every log with the old mill and I have a debarker now. Also I have more hp, so I push them harder. I use resharp and don't keep track of how many times a blade gets sharpened. It does seem like I have more blades culled out that I didn't expect to get culled. For example I know if I send 15 blades in and 2 have hit metal, I'll be lucky to get more than 13 back, but it seems like even if there's no blades that hit metal, I only get 12-13 back. 

[JBS 181]

I dont cut alot of larger diameter logs,but I would think blade life would reduced simply because of cutting wide and putting more stress on the blade.

[tawilson]

Probably should add in that there should be less trips around the bandwheels per cut so may reduce the stress.
I would think Woodmizer would have some pertinent info on this.

[terrifictimbersllc]

Isn't the blade on a wide only about 12"  or about 8% longer?

[tawilson]

171".

[tawilson]

Isn't the blade on a wide only about 12"  or about 8% longer?

My math agrees.  You're saying not enough to make a difference? When you actually do the math you are probably correct.

[CCCLLC]

My Lt 40 wide with diesel is actually 11 percent faster on SFPM over my Lt40  gas. So the longer band is still actually making more revelutions.

[tawilson]

But you probably get through the log faster. Maybe beating this to death but I wondered about this from the get go and enjoy batting it around, again. To many factors to consider,  Woodmizer needs to do an side by side experiment so I can sleep nights.

[terrifictimbersllc]

You're saying not enough to make a difference?

Yes that's what I meant with respect to dulling.  Now if they broke sooner I wouldn't be surprised.

[terrifictimbersllc]

Woodmizer needs to do an side by side experiment so I can sleep nights.

I can imagine at least one rep there might tell you to try some sleeping pills. :D :D

[Magicman]

For example I know if I send 15 blades in and 2 have hit metal, I'll be lucky to get more than 13 back, but it seems like even if there's no blades that hit metal, I only get 12-13 back.

I am on the "auto replace" or whatever it is called.  Cull blade(s) are replaced at a discount so I always get the same number of blades back that I send to ReSharp.

[caveman]

If  we were still using resharp, we would want them to replace blades so we would keep the same number in rotation.  

In my little brain, sawing the same size/species/comparable in every way logs, it would seem that the slightly longer bands would saw a slight percentage more before becoming dull and would also seem to have a little longer life due to fatigue of going around the wheels if both mills drive the blades at the same speed.

If the tension is higher on the wider headed mill (don't know if it is), then that seems like it might negatively impact blade life.

As these mills become more popular I suppose we may eventually get a definitive answer or see a trend.

Thank you for your responses.

[Crossroads]

I may end up changing my preferences with resharp to get replacement blades. I do wish there was an explanation for the culls, maybe there's something I could change in my operation to reduce the number of culled blades. 

[terrifictimbersllc]

They will send the rejects back if you ask.

[Crossroads]

I knew they would send them back, but do they say why they were rejected? I'm wondering if some of my blades have been rejected simply because they have pitch or even a little rust on them? If that's the case I could do a better job of cleaning them. If they're damaged or cracked, I can see them getting rejected, but if they're getting rejected for not being clean enough, I can fix that. 

[Magicman]

I would give your ReSharp center a call, but I would not think cleanliness would be an issue.  I always label any metal strike blades that I send back but if I see much damage, it doesn't go back.  Cracks or the blade being sharpened too many times and loosing it's width would be major reject reasons.  By then it has been resharpened beyond it's "Doublehard" anyway.

[tawilson]

Woodmizer has a machine to clean your blades. I made a point to check it out at the last owners day. It's thorough so I doubt that's the issue. If I took a pic or video I'll dig it out. I think it takes some set out too.

[tawilson]

Memory failed. It deburrs and cleans after sharpening. I knew it had another function, just not removing set.

[terrifictimbersllc]

Put a note in the box asking them to let you know why any blades are rejected.  Or call and ask after you get them back.  The guy who sharpens them probably will be happy to tell you. 

[longtime lurker]

Back to the original topic I dont know the pricing difference for the longer band but if it all comes off the same reel of stock (which it will) then if a band is 10% longer it will cost you 10% more, give or take. (Welding cost is the same either way)
So any extra life you get out of it from having more teeth is paid for at the start.

However being longer its subject to greater torsional forces in use. The length of band to stress thing is exponential not linear... so the longer band will fail in the body sooner. Leastways thats how it works with the big ones - you guys might run out of tooth to sharpen before you get to that point because you dont retip them but I imagine the same principles would apply.