CBN

[Peter Drouin]

Has anyone worn out a Wood Mizer CBN wheel out yet?
And if you did how many blades did you do?
or how many sharpens

[terrifictimbersllc]

and how did you first notice it was worn out?

[Peter Drouin]

and how did you first notice it was worn out?
[/quot


It was sharping a little, but I had to go around 2 times and It did not do the job. Maybe 6 times  :D :D :D
Cutting frozen hemlock is the pith but I have to get 12,000 bf out.
I have a new one on its way. How are you doing with yours? I was hoping to hear from more members with CBM.  I want to thank you for your question.

[terrifictimbersllc]

Don't think any of mine are worn out yet. Oldest two are a 10 and a 9.    Newer are a 4 and a 7.   Probably approaching 400 go rounds with the 10 degree wheel.  I figure if the blade gets sharpened and there are still mounds of metal in the oil, then the wheel isn't worn out.

I do have to go around 2-3 times sometimes, and that's always because of the inside set teeth.  These are always the ones that get completely squared off last in a sharpening. Thinking maybe its because these are mostly new blades which were set last at the factory, so their tops are pushed over different from ones I've already ground.   I set, then sharpen. 

[tommone]

First part of the wheel to wear out is usually the part which grinds down the face of the blade as that part is much harder than the remainder. Although the back of the blade face is also hard the part of the wheel touching that area does not experience as much wear. When the you see a smooth shiny spot at the face grinding area  on the wheel it's time to think about a new wheel.

[woodyone.john]

I bought my sharpener and setter 2nd hand along with the mill with 3000+ hours on the clock.I didnt really know any thing about bandsaws at that time.I didnt get much history on the mill.Oh what a steep learning curve. I wasnt getting a very good cut with my resharpens and this was due to the cbn wheel being worn on the squarish corner in the gullet under the tooth.Tried getting bands sharpened by others [so called profeessionals] and was not impressed.I bought a new 10 degree cbn wheel, that and pineywooded the setter and with the help of the forum started to sharpen my own again. Boy ,what a difference. Any way to the point of the thread,the newest wheel is now looking quite shiny on the corner,not worn out. I wouldnt  have done 500 cycles-bands since new. They are quite expensive here and the thought that soon i may have to replace it makes me squirm in spite of the fact that they are [the ability to sharpen my own] are /is key to sawing.   cheers john

[Peter Drouin]

I do have to go around 2-3 times sometimes, and that's always because of the inside set teeth.  These are always the ones that get completely squared off last in a sharpening. Thinking maybe its because these are mostly new blades which were set last at the factory, so their tops are pushed over different from ones I've already ground.   I set, then sharpen. 
[/quote]




I saw that with the inside teeth, so I move the part that holds the blade out to me. And it's better. I grind heavy. Most times I go around 1 time, sometimes 2. I have sharpened 635 blades with the CBN not counting going 2 times around for a blade. I set first. too

[Peter Drouin]

I bought my sharpener and setter 2nd hand along with the mill with 3000+ hours on the clock.I didnt really know any thing about bandsaws at that time.I didnt get much history on the mill.Oh what a steep learning curve. I wasnt getting a very good cut with my resharpens and this was due to the cbn wheel being worn on the squarish corner in the gullet under the tooth.Tried getting bands sharpened by others [so called profeessionals] and was not impressed.I bought a new 10 degree cbn wheel, that and pineywooded the setter and with the help of the forum started to sharpen my own again. Boy ,what a difference. Any way to the point of the thread,the newest wheel is now looking quite shiny on the corner,not worn out. I wouldnt  have done 500 cycles-bands since new. They are quite expensive here and the thought that soon i may have to replace it makes me squirm in spite of the fact that they are [the ability to sharpen my own] are /is key to sawing.   cheers john

First part of the wheel to wear out is usually the part which grinds down the face of the blade as that part is much harder than the remainder. Although the back of the blade face is also hard the part of the wheel touching that area does not experience as much wear. When the you see a smooth shiny spot at the face grinding area  on the wheel it's time to think about a new wheel.

The wheel is the width of the spacing of the teeth, so I try to put the wheel evenly on the blade. I don't favor one way or the other

[drobertson]

I cannot remember where I saw it, but it seems the cost and life of the cbn wheel is just over the cost of new blades, I know from much polishing, and diamond grinding, there are dressing sticks that get a little more from this type of wheel.  david

[Bandmill Bandit]

my wheel is a in its 8th season.

New bands get set sharpened re set before they see the mill. Been through 28 boxes of bands with 29 and 30 in the shop. box number 29 has 3 blade in the sharpen cycle right now. I average 6 to 8 sharpen cycle per blade so 7 X 280 = 1960 and if you count the odd double round to bring a damaged blade back to good cutting condition I think it is safe to say I am over 2000 blade cycles.

Cant say I have noticed any difference from when the wheel was new to todays performance. i still get a good sharp blade on a single round. keeping the grinder properly adjust is the KEY to this IMHO. I expect at least another 18000 or more cycles minimum. I might be out to lunch but I don't see why it wouldn't do that with proper care. 

Peter; I was having that problem for a bit too. MY wheel angle was way out of set. i got it  set  properly and now i check the set angle about every other blade or so. have not  had that issue since.

[Peter Drouin]

Bandit what do you have for blades, what size, with that kind of numbers you have me thinking WHAT  :D :D

[customsawyer]

I wish I could help you but I don't keep track the number of blades I have sharpened with the grinder. I am on my 3rd CBN wheel now. The first one did well over 500 blades. The second got ruined by hired help . The third has done well over 500 also and still going.

[terrifictimbersllc]

I saw that with the inside teeth, so I move the part that holds the blade out to me. And it's better.

Wondered if I could do that but didn't know how. How'd you do it?  The back bar looks like the one that moves to clamp the blade so is it the front bar that needs moving forward? Is it those two small bolts facing forward on either side?  Underneath there's a bolt but that looks like it just swivels the assembly.  I'd look closer but it's cold out there right now.

[Peter Drouin]

That big bolt[ under it] will let the whole thing come to you. Then you have to turn in the 2 small ones that have the springs behind them so the clamp will hold the blade.

[terrifictimbersllc]

Thanks. Maybe Ive been doing too much grinding, hopefully mostly one pass after this adjustment.  I tend to yank a blade from the mill sooner rather than later trying to saw only with very sharp blades.

[NMFP]

@ of my 10 degree cbn wheels have over 1200 sharpenings on them.  Getting worn down but based on sharpening quality, I think I will get about 300 more sharpenings from those wheels.

The life of the wheel all depends on how you sharpen and how you cool the wheel.  Light grinding is the way to go, not one heavy pass.

Most bands I sharpen are one pass but if a customer has sent a band to me with the tips worn severely, it might require 2 or possibly even 3 passes to renew the steel.

[Bandmill Bandit]

Bandit what do you have for blades, what size, with that kind of numbers you have me thinking WHAT  :D :D

I use mainly the double hard 10* X7/8 ths gullet, .045x1.5 bands with a few stalite bands throw in when I am cutting flooring or paneling. At 280 bands in, I am about roughly half through my wheel based on custom sawyers numbers.

I was taught to sharpen by Garry at the Salmon Arm Wood Mizer shop and he was very adamant that a "light touch" is the key to long wheel life AND the best possible sharpening result.

Heres the hint he gives to about every one he trains;

"if you cant hear the double touch of the grind wheel when the cam hits its lowest point of travel you are grinding to way heavy".

I have to sharpen bands today and will see if I can get my son to come do a high def video of the process for me to post here with sound.

My blades come off when they are still cutting pretty good. I installed a tach on my engine and it is pretty easy to tell when a blade is getting dull. Once I start seeing a drop of more than an average of 100 to 150 rpm its blade change time. You can feel it and hear as much as see it long before you start getting bad cuts. Also the saw dust changes texture too.

Have a set of digital temp gauges on order as well. I think engine temp will be a better indicator than RPM.     

[Peter Drouin]

I can hear the 2# drop of the wheel when I sharpen. And I do change blades when I hear  the mill change sound. I can tell by the feel of the mill too.
Once you get past the hard part of the blade all bets are off. The cat can round off the outside corner in one pass. :D only the blades that have some hardening left will cut frozen hemlock, sometimes after one cut there might be teeth missing on the blade. When I have a blade that has missing teeth or just the top 1/2 gone I throw them away.

[Bandmill Bandit]

Yea Peter you are bang on.
I don't think I have ever got more than 8 sharpens out of a blade before the hardening is about gone. Most bands tend to break at around the 6th or 7th cycles for me anyway.

Blades in reasonable shape a with a tooth or 3 missing get parked for when I get asked to saw a power/utility pole

[Peter Drouin]

Yes I have 3 blades for junk logs  :D :D :D

[terrifictimbersllc]

My grinder noise "chee-chee"  attracts chickadees sometimes they get stuck inside the garage. 

[JustinW_NZ]

I bought my sharpener and setter 2nd hand along with the mill with 3000+ hours on the clock.I didnt really know any thing about bandsaws at that time.I didnt get much history on the mill.Oh what a steep learning curve. I wasnt getting a very good cut with my resharpens and this was due to the cbn wheel being worn on the squarish corner in the gullet under the tooth.Tried getting bands sharpened by others [so called profeessionals] and was not impressed.I bought a new 10 degree cbn wheel, that and pineywooded the setter and with the help of the forum started to sharpen my own again. Boy ,what a difference. Any way to the point of the thread,the newest wheel is now looking quite shiny on the corner,not worn out. I wouldnt  have done 500 cycles-bands since new. They are quite expensive here and the thought that soon i may have to replace it makes me squirm in spite of the fact that they are [the ability to sharpen my own] are /is key to sawing.   cheers john

Hey John, don't happen to have a photo of what your old one looked like do you?
Mine is the same I think, the front edge just isn't sharpening as well as it should I think.

Cheers
Justin

[woodyone.john]

Sorry Justin,I chucked it.I also need to chuck about 50 blades both broken and with no more blackness on their teeth[induction hardened]. As others have commented they arent up to much once thats gone.I,m using 10 .45 1.5 double hards. Ive got the setting and sharpening process sorted now,sufficient at least to make the sawing fast and pleasurable [by my standards],sawing salignas felled a year ago and newer. I now need to consider other elements of the production chain and possibly other patterns to speed and improve recoverys.cheers john

[JustinW_NZ]

Sorry Justin,I chucked it.I also need to chuck about 50 blades both broken and with no more blackness on their teeth[induction hardened]. As others have commented they arent up to much once thats gone.I,m using 10 .45 1.5 double hards. Ive got the setting and sharpening process sorted now,sufficient at least to make the sawing fast and pleasurable [by my standards],sawing salignas felled a year ago and newer. I now need to consider other elements of the production chain and possibly other patterns to speed and improve recoverys.cheers john

yes, I've found the same with the hardened part of gone they don't last long in sharpness terms.
I've got the setting and sharpening working pretty good now as well, but I feel the edge is gone from my wheel, im just trying to put off spending the money I think, probably being too tight about it really 

Cheers
Justin

[Peter Drouin]

[/quote]

yes, I've found the same with the hardened part of gone they don't last long in sharpness terms.
I've got the setting and sharpening working pretty good now as well, but I feel the edge is gone from my wheel, im just trying to put off spending the money I think, probably being too tight about it really 

Cheers
Justin

[/quote]




They don't last forever Justin  :D And yes you have to spend money to make money :D :D Good luck