# bandSaw mill trouble shooting!



## FJH (Jun 14, 2007)

I,m having a bit of a time with my band mill wandering and diving latly!
Is there an order in which you guys work thru these problems?
The blades are sharpe and and set the alinment of the wheels is correct the guides seem correct! blade tention comes into question for me!What happens if its too tight ,what happens when its too loose?Tim At cookssaw claims the curvature of the blade is a big part of these problems I see no humps top or bottom of any of the blades!Yet every blade does the same dam thing! real frustrated with this!Might get one or 2 good passes in and I start having greif

Any comments on this!
much apresiated
Thanx! Fred


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## Sawyer Rob (Jun 14, 2007)

What brand and model of bandmill??

Rob


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## redprospector (Jun 14, 2007)

Just a shot in the dark, but check your band wheel bearings. Mine went bad, and I almost went nuts before I figured it out. Your problem sounds similar.

Andy


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## flht01 (Jun 14, 2007)

Like Rob ask, type of mill would help.

Are the blades new or have they been used/resharpened a few times? All blades from the same mfg? Pitch and band thickness the same?

What method do you use to set band tension?

Are the problems specific to one type of wood or does it do this with several species? Wet (green) logs or dry, hardwood or softwood?

What type of guides does your mill use?

Not trying to get you to write a book but a little info will help troubleshooting.


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## FJH (Jun 15, 2007)

Its my u biult http://photoshare.shaw.ca/messages/viewshow/7685528731-1172719178-38857/preview/page/ Milling fir
7/8 pitch resharpened blades the wheels haven't changed a bunch since i started with the thing!No real wear to speak off there is no crown on the wheels its been working fine until a week back.brand new blades work perfect
first time thru brand of blade makes no diffrence I have wood miser I have lenox and cooks!All are doing the same thing!I tention with a heavy spring!and screw afair.I may be running to tight I have been running a bit tighter than normal! Don't just though you guys may have some thoughts on it!
What went wrong with the wheels you had?


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## scottr (Jun 15, 2007)

FJH , have you checked the bands that dive for the lateral curve with a flat bar and light ?


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## FJH (Jun 15, 2007)

redprospector said:


> Just a shot in the dark, but check your band wheel bearings. Mine went bad, and I almost went nuts before I figured it out. Your problem sounds similar.
> 
> Andy


Thats a possiblity! the wheels seem to spin free with no movment side ways!
They ar tapered roller 3/4 ton truck hubs!


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## flht01 (Jun 15, 2007)

FJH said:


> ...brand new blades work perfect...



Am I understanding this right, new blades cut perfect and the resharps are the problem?

Who's doing your resharpening?


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## FJH (Jun 15, 2007)

YES! correct new blades Have been working fine for the first 2-3 hours!(I have been told that 2-3 hours is All I can expect from these blades in fir!)

My resharpe guy is a real fuss budget!(I BELEIVE) He is a perfection freak!
He sets and sharpens As needed and has done an excellent job for me so far I even took three blades back to him after a pass or 2 and had him redo them to make sure his machine wasn't messing things up! He sets with a tooth by tooth jig not an auto setter 23 to 28 thou offset on 042 blades Ect.Beleive me we have checked the blades!

(I have to beleive its somthing with the mill!)
I will pull thw wheels and check the bearings possibly this weekend and check that out!

Being home made I realize its hard for you guys to give accuate trouble shooting but any info is better than none! 

Also I have looked into the curvature thing and (IF) I'm Doing it right They apear flat! No crown top or bottom!

In the meantime
Keep the Ideas ,questions and thoughts coming!

Thanx Guys
Fred


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## flht01 (Jun 15, 2007)

I think if it were me, I'd send a few of the problem blades to Cook's saw and have them resharpened. If the new blades are working good for you and the resharps aren't, having another facility resharpen a few to test would help narrow the problem down to either blades or the mill.

Not trying to imply your resharpening service isn't up to par, but having another facility look them over might help.


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## MJR (Jun 15, 2007)

I am by no means an expert, but I can tell you about my experience with a diving blade milling Norway spruce. I took the top cant off and then took the second cant off. I then noticed the prettiest wave pattern in the cut. I could not believe the blade could dive into a log that deep. I changed the blade and made a nice smooth cut. Being a man of science I put the old blade back on. I then made the second prettiest wave pattern I ever seen. I put the new blade back on and made a nice smooth cut. 
I was trying to get one more log out of the blade before I changed it. Instead I wasted the log, but learned a lot. I seem to get about 4hrs. on a Lenox Wood Master Blade milling Spruce. Again, I have only milled 38 Norway Spruce logs (yes I am counting) and don’t claim to be an expert.
You may want to look into finding a second source for sharpening your blades. From the looks of your mechanical skills based on your mill, I would bet if there was something wrong with the mill you would have noticed it by now. If it is a mill issue shouldn’t also affect a new blade? Best of luck…


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## FJH (Jun 15, 2007)

MJR said:


> I am by no means an expert, but I can tell you about my experience with a diving blade milling Norway spruce. I took the top cant off and then took the second cant off. I then noticed the prettiest wave pattern in the cut. I could not believe the blade could dive into a log that deep. I changed the blade and made a nice smooth cut. Being a man of science I put the old blade back on. I then made the second prettiest wave pattern I ever seen. I put the new blade back on and made a nice smooth cut.
> I was trying to get one more log out of the blade before I changed it. Instead I wasted the log, but learned a lot. I seem to get about 4hrs. on a Lenox Wood Master Blade milling Spruce. Again, I have only milled 38 Norway Spruce logs (yes I am counting) and don’t claim to be an expert.
> You may want to look into finding a second source for sharpening your blades. From the looks of your mechanical skills based on your mill, I would bet if there was something wrong with the mill you would have noticed it by now. If it is a mill issue shouldn’t also affect a new blade? Best of luck…


thanx for the vote of confidence! BUT!
Maybe I am noticing it but don't see it??
The blades I'm using in question right now are the lenox blades resharpened!
I have new ones on the way but in the meantime I'm 2 cuts into a 24 inch fir and don't want to waste the wood as its prime floor joist material!
Im into it to the 12 inch mark and this has started.
I'm going to lossen the tention first (cheap and easy) then work from there I guess!Normally tention right up and back off 1/4 to 1/2turn lately as these problems developed I have been tightening !Mabe I should be loosening!
If this persists I will send the blades back to the dealer and have them sharpened as suggested and see if that makes the diffrence!


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## FJH (Jun 15, 2007)

OK Guys I tried the tention thing !Two or three diffrent sets looser and another lenox resharp blade no good! still Diving!Wheels will come off this week end for a bearing check and I may surface the wheels maybe there worn more than I can see!
i'll keep ya posted keep the ideas coming


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## infomet (Jun 15, 2007)

If the wheels were the problem, how could the new blades run well?
I can't get the picture(s). How about reloading a bunch.
I have used a hired Woodmizer a lot and never had a diving problem except with a badly damaged blade. We have run resharpened blades for a half day or more in pine. A little less in oak and hickory.

It's hard to believe a tighter blade would dive more.

How about the little idler wheel bearings? If the input side idler were tipped )down), it would get the blade off to a bad start!


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## FJH (Jun 16, 2007)

Ive been thinking ,WHAT A MORON,I messed with the guide bearings a month ago!I may have upset the apple cart .I will start from scratch on the set up and see what washes out!I checked the wheels with a level yesterday the wheels are perfectly level and so is the mill!That dosent mean the guides are right!I'll try heeling them back some see if that does the trick!

http://photoshare.shaw.ca/messages/viewshow/7685528731-1172719178-38857/preview/page/

Make sure you Click on The preveiw portion of the link!


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## mountainlake (Jun 16, 2007)

How much down pressure are you running on the guide wheels. My mill recommends 1/8" but I run around 1'4", it cut a lot straighter. That still wouldn't explain the difference between the new and sharpened ones, are you sure they have enough set, leaving sawdust on the log. Steve


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## FJH (Jun 16, 2007)

Give me a chance to change and to try this i think i may have done this to my self!
i'll let you guys know!


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## FJH (Jun 17, 2007)

Ok I started from scratch It was a way Out of wack OPPOSITE to what I would have thought!The blade rollers were angled Up not down real strange As the blade pulled down not up!I still havent tested it but Everything is now set to 0 , and am hoping things will be back to normal!If this don't work I may pull the wheels and check the bearings!If it does work,I still don't get why the new blades worked and the resharpes didn't!?

By the way 1/4 down on the rollers is where I have them set!
Thanxfor the reminder thou! 

Also In regards to the photos I have noticed you have to click on that photo share link twice sum times to make it work ! Go into it then close it ,then go in again and it will work!

http://photoshare.shaw.ca/messages/viewshow/7685528731-1172719178-38857/preview/page/


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## redprospector (Jun 17, 2007)

Sorry I haven't checked this for a few days.
If new blades are giving you 2 to 3 hours the bearings probably aren't the problem. There are a lot of things in the sharpening process that can give you this kind of grief. Check the depth of the gullet on the resharpened blades against a new one, then check the shape of the gullet. Too much hook can give you a problem in Doug Fir, a blade that cuts an old seasoned log fine won't do as well in a green Doug Fir.

The bearings on my mill are pillow block, they seemed to turn smooth but when put under pressure the balls would turn to the bad spots, change everything. I would get from 1 to 5 good cuts, then it would go to crap. 

Logic say's that if new blades work fine, the problem has to be in the sharpening process. The best control you can have on blade sharpening is to sharpen them your self. I set mine with the small manual setter from Cook's, and I sharpen them with a (don't laugh) modified bench grinder. This works well for me, and if I have problems with a certain species I can play with the set, hook, and gullet geometry untill I get it right. Take notes so you don't have to invent the wheel again.

Andy


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## FJH (Jun 18, 2007)

redprospector said:


> Sorry I haven't checked this for a few days.
> If new blades are giving you 2 to 3 hours the bearings probably aren't the problem. There are a lot of things in the sharpening process that can give you this kind of grief. Check the depth of the gullet on the resharpened blades against a new one, then check the shape of the gullet. Too much hook can give you a problem in Doug Fir, a blade that cuts an old seasoned log fine won't do as well in a green Doug Fir.
> 
> The bearings on my mill are pillow block, they seemed to turn smooth but when put under pressure the balls would turn to the bad spots, change everything. I would get from 1 to 5 good cuts, then it would go to crap.
> ...



Andy You may BE THE MAN!
After doing the whole set proesedure a second time with marginal sucsess I found the idler wheel had some movment I have since removed it checked and repacked the bearings which where fine except for being a tad loose! Having said that i am not willing to condem the blades till I have double and triple checked my end first!I will then try sending a blade off for checking by somone else!The new blades being almost perfect may have masked this problem!

Thanx
Fred


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## FJH (Jun 19, 2007)

Ok guys I have done everything I can think of And am having very little luck!
A bit better but The blade is consistantly diving into the log!I got two decent passes in then it started diving !the blade is set perfectly the roller guides tooEvrything is set to 0 so I guess i will have to try somone else for sharpening and see if that helps!
Are there any sets you guys have tryed to address diving only??


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## redprospector (Jun 19, 2007)

I think you said you were cutting 24" Fir (I assume it's Douglas).
It depends if the wood is green or not, but I usually set mine at about 25 thou. for that size Fir. You shouldnt use more than a 10* hook in fir, and your gullet needs to be full depth, I'm just guessing on your brand of blades but probably about 5/16". 
If the sawdust is packing on the log, increase your set a couple thou.
If a lot of sawdust is staying on the log, but is loose decrease your set a couple thou.
The size of your logs will dictate the set.

Andy


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## mountainlake (Jun 20, 2007)

Fred Are the teeth of the blade protruding out in front of the band wheels far enough? Maybe to close and taking some of the set out after a few cuts. Sharpened blades would be worse being a little thinner. Also check for anything rubbing on the blade. Steve


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## infomet (Jun 21, 2007)

Are you checking the blade level against the plane of the bed? If a front carriage wheel bearing were bad it could lower the front of the blade??


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## FJH (Jun 21, 2007)

I 'm not sure yet But i have possibly found my problem I found I was having wander problems after reseting EVERYTHING including the above mentioned  and packing idler bearing.
My problem may have been The blade back up bearing its working good with a new blade now , just got to try the resharpes I'll let you guys know!

Thanx for the input you guys!


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## redprospector (Jun 21, 2007)

I hope you get it figured out, I know how frusterating it can be figuring out these kind of problems.

Andy


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## mountainlake (Jun 27, 2007)

Fred 
Do you have that mill cutting straight yet or are you on vacation? Steve


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## FJH (Jun 27, 2007)

Sort of! Back to cutting straight with new blades!I have yet to try the sharpes as I needed perfect wood!
I'll post when i get at them re sharpes!
also I took some rpm shots on the wheels again today And i'm only getting 650 RPM on the wheels With a 23 inch wheel that puts me a way below what the blade speed needs to be!I think i need to make the drive pulley smaller in order to get more speed!Bascicly the horse power is not a problem the tractor will drive the pump as fast as it needs to go but at full open 650 is not enough.
I can open the rpms up on the tractor but loose my fuel economy I'm 1200 rpm on the tractor right now if I jump it to 1500 it will cut faster but the fuel economy sucks!you don't need much horse power to cut, it moves along effortlessly to cut.But have to move slowly thru wide cuts!
What do you guys think on this?


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## redprospector (Jun 27, 2007)

If you have enough power to drive it, I'd go down on the pulley size. 650 RPM sounds pretty low. I'm sure there is a difference in our wheel sizes, but Mine turns 925 RPM.

Andy


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## FJH (Jun 28, 2007)

Andy I talked with Tim Cook on this and he sets their saws like this!

First thing the Roller Guides must hold the blade straight away, never leading up or down. ( this could be a change from previous writings, but I have done much experimenting and have proved the guides must direct the blade straight away. Just like aiming a gun to shoot. to direct the bullet it must be aimed in the wright direction to hit the intended target. In sawmills the intended target is straight away.

Second question. I am speaking of from a square position from the log bunks to the wheels. I want the wheels to tilt forward at the top towards the log 1/8 of an inch. Because of the variance of measuring I will say 1/16 to 1/8. But on our mills I perfer 1/8. 

If you think your wheels are square Now, then measure to the guard and write down the measurement from the top and the bottom. then move them forward at the top toward the log to have a difference of 1/8 from top to bottom.

Here is the bottom line. if your blades is flat and the guides are straight away, and the blade rises in the cut you need to move the wheels forward at the top towards the log. I would not move the wheels untill I knew the blades are flat. 
The blades will saw to the least path of resistance. we need this to be straight away.

Remember : the way to get the same results is to repeat the same thing over again.



Would you agree or dis agree with his thoughts I beleive its worth tring Only a couple of wavy cuts away from perfection!   :jester:


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## redprospector (Jun 28, 2007)

FJH said:


> Andy I talked with Tim Cook on this and he sets their saws like this!
> 
> First thing the Roller Guides must hold the blade straight away, never leading up or down. ( this could be a change from previous writings, but I have done much experimenting and have proved the guides must direct the blade straight away. Just like aiming a gun to shoot. to direct the bullet it must be aimed in the wright direction to hit the intended target. In sawmills the intended target is straight away.
> 
> ...



Fred,
When trouble shooting a band mill, guys like Tim are your most valuable resorce. They make their living building and developing these machines. 
To answer your question, yes I agree. The guides are exactly that, guides. But they depend on a true blade. I have never delt with the flatness in the blade backs, but I read the article Tim wrote in the last catalog they sent, and it makes sense. When I get back to sawing, I'll have to send them a few blades and see if it makes a difference.

Andy


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## FJH (Jun 28, 2007)

yup for sure !I'm going to try his set this week end I HOPE! I've finished the cedar 2 x 10s that I was sawing And will be back at 1x6 next would like that to come out straight too so i will chuck it up and reset as tim has discribed and give it a go!if i does't work i will reset to my curent set!Square to the deck parralel to the deck!


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## FJH (Jun 30, 2007)

Well setter up to the Cooks set and all seems much better with (new) Blades
Will try The re sharpes tomorrow !I find the blade tends to limb the first 4 inches aprox 32 of an inch then finds the sweet spot Any fixes for this ?


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## infomet (Jun 30, 2007)

Increase tension?
How are you measuring tension?

Tilt guide rollers down VERY slightly?
Is the blade against the shoulders of the rollers before starting the cut?


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## FJH (Jun 30, 2007)

infomet said:


> Increase tension?
> How are you measuring tension?
> 
> Tilt guide rollers down VERY slightly?
> Is the blade against the shoulders of the rollers before starting the cut?



>>tention
I don't measure tention (Wish I could)The tentioner has a huge Truck draglink spring behind it!I tighten till it stops and back off 1/4 turn!Standard coarse thread on the adjuster!

>>Is the blade against the shoulders of the rollers before starting the cut? YES always!

>>Tilt guide rollers down VERY slightly
Was going to try that next!But Waiting to hear back from Tim cook on that!

I also cranked up the rpms on the pto !Havent took wheel speed yet but its running a whole lot faster!The down side to this is it's heating the oil too much and have to shut down after four hours.Bottom line on this situation is ,I have to reduce the pulley size on the drive wheel to get the speed up so I can run in low gear pto.I'm running 11.75 pulley on there now!My next step down is 8.75 I'm going to order this up and try it the pulley is 40.00 bucks worth a shot I think!
Its sawing much better Aside from the 1/32 ramp up! I did a stack of 6 ft long cedar fence slats maybe 35 peices 1 inch 5 1/2 boards with out a problem no wave anyway! 2 cants side by side.
till i get this lift resolved I don't want to try the resharpes!


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## redprospector (Jun 30, 2007)

Fred,
I'm glad you're getting it all figured out.
I think talking to Tim is a smart move. I can make my old home made piece of crap cut pretty good, but when something isn't quite right I spend hours just looking, and scratching my head. Tim really knows what makes these saws tick and can steer you in the right direction.
Let us know what it takes to correct the little climb when you get it figured out. I'm taking notes.  

Andy


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## FJH (Jul 1, 2007)

My 1/32 rise may have been a contamination thing!As i was lifting the boards off the stack I cut last nite I found a nail stain.a nail not once but three pases worth!  the blade is a bit dull at this point! I also noticed I had hit a nail with the previous blade as well so I am not touching a thing till i CHUCK up another log and give it a chance.


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## FJH (Jul 2, 2007)

Hey Guys ! put a resharp on today and All is well Pretty much perfect cutting !No rise no dive Cutting 12 inch cants! the new blade took a dive When I got into the 24 inch peice of cedar I THINK because of tention in the wood I learned that I should put a wedge in the log after enteing it 6 inches or so,(Specially butt wood) It started binding on the blade As I cut causing it to dive in. I could see this on my preasure gauge and should have clued in  !I'm still left with the blade speed issue which i hope to solve next week with an 8 3/4 pulley on the drive wheel instead of the 11 3/4 thats on there.That should up the speed a 1/3 dramaticly and be able to get some decent wheel speed @ low tractor rpms and still have some decent torque.
anyway ,I'll likly be asking more dumb questions as time goes on !Who knows i maybe able to help the other way around sumtime.


Thanx for your guys input.
Fred


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## redprospector (Jul 2, 2007)

Glad you got her worked out Fred.
My Dad used to say that the only dumb question is one that you already know the answer too. I don't know too much, and I sure learned some on this thread.

Andy


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## FJH (Jul 2, 2007)

Is anyone from this site lucky enough to be using a cooks mill . I would imagine the after service to be exceptional!
Tim has helped me a great deal over the past few months.I have the sharpening guy telling me this that and the other but He has no idea about what you run into whilst cutting !I find the tension in the wood to be the most frustrating!You can never tell when a log has tension it can look perfect and take off in a moments notice.

thanx again for listening

Fred


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## FJH (Jul 7, 2007)

Well men ,Just to up date you guys ,I think the worst is over i hope for now !All of the blades seem to be doing there job now even most of the problem blades!
I upped the the rpms on the wheels 1/3 and am thinking I may do one more pulley change ,and drop from 8.75 to 7.75 pulley to get just a little more out of it Im running approx 830 rpms no load now and a little fluid left to spare (Not MUCH)to run the height control.The drop should enable me to get a decent amount of oil to run the height control no problem , keep the saw at the 4800 to 5000 bfpm and keep the tractor rpms where I'd like em. 12- 1300

Again thanx for the help!
And the input.

Fred


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## redprospector (Jul 8, 2007)

If you're running your blades at 4800 to 5000 sfpm you could up your blade speed some. It depends on your blade size and construction, and wheel size.
If I remember right I'm running mine at about 55 or 5600 sfpm.

Andy


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## FJH (Jul 8, 2007)

redprospector said:


> If you're running your blades at 4800 to 5000 sfpm you could up your blade speed some. It depends on your blade size and construction, and wheel size.
> If I remember right I'm running mine at about 55 or 5600 sfpm.
> 
> Andy



Andy

If you go by what Tim wrote in this article

http://www.cookssaw.com/Articles/bandsawturn.php 

I,m right in the zone now just want that little bit extra oil for height control! as my head rig lifts by the leftover oil that is not being used to turn the wheels. My wheels are 23.75 inch That means I need aprox 850 - 900 rpm and should @ no load have 1200 just to have that little extra for adjustment.
One thing Tim did not mention was if the speed was in the cut!!?(I asume it is)
I would asume the rpm is going to slow sum in the cut (specialy) in my case using hydralics But even with a motor your going to loose sum!Once I get the new pulley I will take shots on the wheel in the cut and find the sweet spot!


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## redprospector (Jul 9, 2007)

I'd have to check for sure what mine is running. I'm only running 20" wheels with 1 1/2" blades. 
My mill is powered by a 1600cc Volkswagon engine so it really doesn't loose much in the cut. 
My memory on blade speed could be faulty.  

Andy


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## redprospector (Jul 9, 2007)

That's a good article.
I'll have to check some things on my mill and make sure it's about 5500 fps. If I remember right when I built my mill some were saying I could turn it at around 6000 fps.
The only reason I consider wheel size is metal fatigue in the blade. The tighter the radius the faster the fatigue, so in my little mind a little less speed on a smaller wheel = longer blade life (maybe).

Andy


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## FJH (Jul 10, 2007)

Andy heres what Tim had to say about the rise isodent with the new blade!
Also that seemed to heal its self for a time .

Subject: Tims set!


OK Tim !
Did the Cooks set and all seems much better with (new) Blades.
I find the blade tends to limb the first 4 inches into the cut aprox 32 of an inch then finds the sweet spot Any fixes for this ?I'm at aprox 1/6- 1/8 top lead on the wheels now And the rollers are set to the plane of the bed! Should I try and tweak the rollers forward a tad??? Ideas please!!!!

Thanx
Fred

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The Roller guides should always hold the blades straight away , never up nor down. 

if the blade wants to climb when entering, I look at 2 things. #1 look at the flatness of the blade. if Too much dish it will climb. if you have the lead on the top of the wheels at 1/16 I would increase if I could to 1/8, but just a tweak will do it. 

What the blade is telling you is that the least path of resistance is slightly up. It is not refusing to saw, but it is following the easiest path. When enough change is made to make the path straight away the problem will be gone.

Remember if there is a little too dish in the blade it will rise a little out of the box , but will get better when sharpened. By the 3rd run it could be running at its best.
you might watch this to see if it is a flattness of the blade variation.

1 more thing to watch. if the guide mechanism is flexing when you hit the log this will allow a rise. 

As far as the set it seems to be good on the blades. 

hope this helps

Tim




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