# Bands saw blade diving on knots and wider parts in the same log



## BobL (Nov 2, 2021)

I'm trying to get the bandsaw mill cutting straight again and seem to have run into a brick wall.
It was cutting "OK when I last used it a few years back but since getting back to it, every time the blade starts cutting something harder than the rest of the log, like a knot or branch union, or even just entering a wider part of the log the blade dives about 1/4" or so in the cut.
When the cut comes back to straight grain or narrower wood it comes back up again.
Today I finally lashed out and threw a brand new Lenox Woodmaster blade onto the mill so it can't be the blade..
Checked and double checked blade tension, all angles and settings etc.
Any idea gratefully appreciated.
Thanks


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## woodchuckcanuck (Nov 2, 2021)

Only advice I can offer is

To slow your feed rate into the knots.
If you can, reduce your engine speed to about 2800-3000 rpm.
Blade tooth hook angle should be correct for type of log being sawed.
Blade tooth set should be correct for type of log being sawed.
Correct blade tension (you got that covered).
Sharp blade (you got that covered).


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## BobL (Nov 2, 2021)

Thanks Jim,
New blade is supplied by reputable supplied who supplies blades to statewide sawmills to run in our hardwoods.
Most of the wood we cut is pretty hard but I started a few months back cutting up a a pine log and it seemed no different.

RE: Position of blade on wheels/tyres.
The tyres are 1" wide V-belts and the band is 2" wide.
On my home WW bandsaw I run the bottom of the blade gullets almost in the middle of the tyre, but I didn't seem to need to do that before when I used the BS mill.
I've tried moving the blade on the wheels so that the edge of the wheel/tyre is within 1/16" of the gullet but it doesn't seem to make any difference.
If I move the gullets even closer to the wheel edge the back of the blade strikes the inside of the Band guard.


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## Leeroy (Nov 2, 2021)

Bob I hope you can get it sorted out. Bearings or blocks for blade guides?
What WW stand for?
Not sure this info on tensioning is relevant, but I've never heard of this method :


Six Rules Of Sawing | Suffolk Machinery - Timber Wolf Bandsaw Blades


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## woodchuckcanuck (Nov 2, 2021)

WW likely means woodworking.
Assuming you've run 2" blades on 1" wheels/tires before with no issue, I would look to the blades. If your blade is only diving (downward I assume) then you should check the inside set. Its quite possible the inside set is insufficient. Or, the outside set to more than it should be. Is it happening with softwood only, hardwood only, or both?


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## Bobby Kirbos (Nov 2, 2021)

If you can in some way, reverse the cutting direction (not the feed, but the cutting direction of the blade)....
Roll the band ... make what is currently the outer face of the band the inner face. This will also flip the teeth. If the band continues to dive in the same direction, the problem is likely NOT related to the band or the cutters. If the "dive" changes direction with the flip, the problem is likely the band or the cutters.


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## grizz55chev (Nov 2, 2021)

Maybe you need more lubrication during the cut, increase the water feed.


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## nwhunter (Nov 3, 2021)

The back edge of the band needs to run on the wheel, there should be more tension put in the band on the back edge of the band, I would not run a 2" band on a 1" wheel as it would put an excessive amount of the cutting edge forward of the support from the wheel, resulting in the band dodging.


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## CWME (Nov 3, 2021)

I ran into that issue with some knotty hemlock this past spring. I increased my tooth set and the issue cleared up for me.


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## billstuewe (Nov 4, 2021)

Hi Bob! long time since I have been around. I retired in Feb of 2010 and my hobby woodworking became a nice business. I now have a Woodmizer LT40/36hpG. Sometimes it is just the log that causes wavy cuts--especially at knots and other hard parts. The only things that helps is, as woodchuckcan noted: A good sharp band , reduce feed rate and the right tension. I will even increase the tension a bit.
Bill Stuewe
www.billstuewe.com


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## Franny K (Nov 5, 2021)

nwhunter said:


> The back edge of the band needs to run on the wheel, there should be more tension put in the band on the back edge of the band, I would not run a 2" band on a 1" wheel as it would put an excessive amount of the cutting edge forward of the support from the wheel, resulting in the band dodging.


He said an one inch belt I am guessing the wheel is wider than an inch, for a 1 1/4 inch band the wheel or pulley sheave is about an inch and the belt is 5/8. We probably need a clarification here.

BobL are you running roller blade guides and if so how much downward deflection does the fixed one and the moveable one have?


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## BobL (Nov 6, 2021)

Thanks to every for all their replies and suggestions.
Sorry I have not got back to you all sooner.


Leeroy said:


> Bob I hope you can get it sorted out. Bearings or blocks for blade guides?
> What WW stand for?
> Not sure this info on tensioning is relevant, but I've never heard of this method :


I'm using super hardwood (Wandoo) blocks as guides.
WW is woodwork.


woodchuckcanuck said:


> WW likely means woodworking.
> Assuming you've run 2" blades on 1" wheels/tires before with no issue, I would look to the blades. If your blade is only diving (downward I assume) then you should check the inside set. Its quite possible the inside set is insufficient. Or, the outside set to more than it should be. Is it happening with softwood only, hardwood only, or both?


Yes have run any 2" wide blades successfully on this mill. I doubt it's the blades as I've tried two new ones from reputable supplier.


Bobby Kirbos said:


> If you can in some way, reverse the cutting direction (not the feed, but the cutting direction of the blade)....
> Roll the band ... make what is currently the outer face of the band the inner face. This will also flip the teeth. If the band continues to dive in the same direction, the problem is likely NOT related to the band or the cutters. If the "dive" changes direction with the flip, the problem is likely the band or the cutters.


When I say dive, it was both dipping and rising. Mainly diving on entering a knot or branch union and rising back up to normal or a bit less after it cut through the knot . Anyway your suggestion is a Good idea and will give it a go if I need to.


grizz55chev said:


> Maybe you need more lubrication during the cut, increase the water feed.


Water is flooding the blade, plus every few feet of cut I usually add a few squirts of chainsaw B&C lube.


nwhunter said:


> The back edge of the band needs to run on the wheel, there should be more tension put in the band on the back edge of the band, I would not run a 2" band on a 1" wheel as it would put an excessive amount of the cutting edge forward of the support from the wheel, resulting in the band dodging.


The blocks are ~2" wide (and 2" long and about 1.25" thick) and start providing support just under the gullets to past the back of the blade. Its worked very well in teh past.



CWME said:


> I ran into that issue with some knotty hemlock this past spring. I increased my tooth set and the issue cleared up for me.


I've tried this but maybe I need to add even more.


billstuewe said:


> Hi Bob! long time since I have been around. I retired in Feb of 2010 and my hobby woodworking became a nice business. I now have a Woodmizer LT40/36hpG. Sometimes it is just the log that causes wavy cuts--especially at knots and other hard parts. The only things that helps is, as woodchuckcan noted: A good sharp band , reduce feed rate and the right tension. I will even increase the tension a bit.
> Bill Stuewe
> www.billstuewe.com


Yeah have played around wth the tension a fair bit, from 25% less than recommended to 30% more than recommended. Nothing


Franny K said:


> He said an one inch belt I am guessing the wheel is wider than an inch, for a 1 1/4 inch band the wheel or pulley sheave is about an inch and the belt is 5/8. We probably need a clarification here.
> 
> BobL are you running roller blade guides and if so how much downward deflection does the fixed one and the moveable one have?


The mill did come with rollers but they last about half a dozen cuts before the bearings gumed up with sawdust. The previous mill owner replaced the rollers with blocks and we successfully used these blocks for 4 years . The blocks only provide down force and support the blade from the gullets to the very back of the blade. Downward deflection is ~1/4"

Some of the blade dives were so deep the blade would eventually no longer even be in contact with the guide blocks.

The wheels are just over an inch wide and have a deep V-groove that holds a large V-belt. The belts are very loose in the groove and they have always been like that.

Now just to make things entertaining, today it cut straighter than it has cut since I got back to this mill, Blade dive was down from the usual 1/8->1/4" to 1/16->1/32"
What did I do in the meantime?

The first thing was to fix the throat width adjustment. I noticed it was packed with rust and sawdust not well secured so liable to twist. This is now clean, shimmed, greased and secured.

Then I added hard wood plates to support the blade at the guide blocks from underneath.
At both the inboard and outboard sides, the blade effectively passes through a pair of blocks with about 1/32" of extra gap.
If the blade goes for a dive the plates will prevent it going too far. The wooden plates are about 1/2" thick and secured to the back of the top guide blocks by 1/4" thick piece of angle. The hardwood plates ar fastened to the angle with 1/4" counter sunk brass screws so of the wood wears the brass screws won't do anything to the blade.

I cut 4 slabs and was pleased enough, but still I think there is more I can do.

Thaks again to all.


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## BobL (Nov 6, 2021)

Not many photos taken but this is one of the least wavy/divey cuts from earlier in the week.
At least the wood is purdy!


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## Franny K (Nov 6, 2021)

I suppose we should establish if the thickness of the band blade is the same as four years ago. The wheels look large enough to run kind of thick bands,

I have observed that sandwich type guides seem to be used in line with the way the blade comes off the band wheels and roller guides control the band with a downward deflection.

From your picture, turn it so the opened face is vertical and where the blade enters as soon as possible if wave cut is an issue is my current tactic.

From a design prospective I note that Cooks and Baker for their 2 inch blade width models keep the same blade direction but put the log stops or squaring arms on the other side, the enter the cut side. They also put the fixed guide on that side and the moveable one on the exiting the cut side.

The part about the bearings of roller guides gumming up is puzzling as I have never had a bearing issue but the ridges in the roller guides can clog and be frustrating.

You are saying your belted band wheels are an inch wide in total, ?5/8" belt for a crown, I would think for best results the crown of the band wheel should be pretty much the width of the blade from the gullet back.


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## BobL (Nov 6, 2021)

Thanks for the feedback FK.


Franny K said:


> I suppose we should establish if the thickness of the band blade is the same as four years ago. The wheels look large enough to run kind of thick bands,


Yes they are the same blades


Franny K said:


> I have observed that sandwich type guides seem to be used in line with the way the blade comes off the band wheels and roller guides control the band with a downward deflection.


Initially there were two rollers (I still have those and as I said have tried several times to use them bt they gum up.) replaced by 2 downward trusting guide blocks, now there are two sandwich type diodes 


Franny K said:


> From your picture, turn it so the opened face is vertical and where the blade enters as soon as possible if wave cut is an issue is my current tactic.


Yep - understand, problem is the carriage log and squaring arm stops are over on that size and would have to change things around - hoping not to have to do that. 


Franny K said:


> From a design prospective I note that Cooks and Baker for their 2 inch blade width models keep the same blade direction but put the log stops or squaring arms on the other side, the enter the cut side. They also put the fixed guide on that side and the moveable one on the exiting the cut side.


Interesting. Thing is the mill has cut very straight in the past.


Franny K said:


> The part about the bearings of roller guides gumming up is puzzling as I have never had a bearing issue but the ridges in the roller guides can clog and be frustrating.


Yeah it's very strange. I even replaced the bearings with sealed types but they still got gummed up. On my WW BS I only clean the roller bearings every couple of years. I also cut up large beef bones for our dogs with this saw so the rollers get covered in beef fat, the BS tyres also pick up a lot of fat and the get scrapped off every month or so but the bearings never get gummed up


Franny K said:


> You are saying your belted band wheels are an inch wide in total, ?5/8" belt for a crown, I would think for best results the crown of the band wheel should be pretty much the width of the blade from the gullet back.


Yes its kind weird. On my woodwork Bandsaw I've always (for ~15 years) used the Snodgrass set up method where the bottom of the gullets matches the crown on the wheel. Works really well, I can't do this on this mill as the back of the blade would be touching the wheel guards.


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## Franny K (Nov 6, 2021)

BobL said:


> Yep - understand, problem is the carriage log and squaring arm stops are over on that size and would have to change things around - hoping not to have to do that.


I was meaning use a level or square to get the opened log face vertical. Depending on the squaring arms or log stops and the turning method this will vary in difficulty.


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## BobL (Nov 8, 2021)

After last weeks improvements, yesterday I decided to have a go at a partially cut that I had trouble with a couple of weeks back.
I did a number of cuts with the mill, most were OK and then I got a bit greedy and the rise and dive came back although not as bad a before. 

I keep forgetting to take photos but here are couple of the worst ones taken by the boss from a couple of weeks back.


Same log but from the other side.
The shadows and log width changes exaggerate the dive so what looks like a massive dip is actually also a change in log width.


Still trying to work out "Why" things improved.
I think it's a accumulation of factors - slower cutting, slightly higher band tension, blade support from underneath,


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## BobL (Nov 11, 2021)

After watching me struggle for months trying to get the old mill to cut straight the arborist/boss has decided to spring for a new small mill.

He recently got a big order for smallish (60 x 80mm and 60 x 40mm, x 1.8m long) dressed hardwood lumber - there are massive and growing lumber shortages here.
He's really lashed out and bought a spiral headed thicknesser/planar combo machine.
Earlier this week we (me and the boss) prepared a dozen or so samples and the amount of work to produced dressed to size from roughish cut lumber was not lost on the boss which is why he wants to get a new mill.
We'll still use the old mill to break up larger logs while a second operator puts the cants through the smaller one. 
I'll be still driving the bigger mill and trying my best, but I won't have to stress too much about getting straight cuts.
He's looking at a few different mill brands but availability is probably going to be a final determining factor.


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## rogue60 (Nov 12, 2021)

Sounds like it could be a packing problem allowing the band to wander when it hits knots or a wider cut. Normally to much heat makes a band wander but you have plenty of water for cooling. To much feed speed will also make a band wander.
Bandsaws aren't the greatest things at cutting straight when the going gets tough especially in our hardwoods.
If you weren't so far Perth im in QLD you could have our old Bandsaw for scrap money to tinker with.
We used to cut Hoop Pine, Cedar, Silky Oak etc..


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## BobL (Nov 12, 2021)

Thanks for the offer. I have a not that I'd be tempted. I used to have a large collection of old wood and metal working machinery that needed restoration and have only after ~10 years managed to get rid of them.


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## BobL (Nov 23, 2021)

Well, on the 13th Nov the boss placed an order for a Woodland HM130 and apparently it arrived yesterday - so all up 10 days.
Given that it was 2600 miles away in Brisbane (on the other side of the country) and a lack of transport vehicles and drivers, plus all the border restrictions between States due to Covid etc I'd say that's pretty good. I'm itching to get down to the yard (29 miles away) to start assembling it but have babysitting today so it will have to be tomorrow.


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## BobL (Nov 25, 2021)

Started the assembly process this morning and it took us about 3 hours just to unpack the boxes and assemble the bed/rails. Looks nicely made.
I had to leave the boss reading the manual at around 1pm as I had to go off and do other things
Will take some photos next time.


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## BobL (Nov 30, 2021)

Mill is finally assembled and this morning we made the first cut.


All working good so far with nice straight cuts .


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## BobL (Dec 2, 2021)

Spent yesterday morning setting up the water lube system and cutting up some small Silky Oak logs with the new mill. 
The first cuts were like butter but the sapwood was riddled with termites and loaded up with sand and muck which knocked the hell out of the blade.
Had to stop cutting after the third log as it was barely cutting.
Apart from that its very nice to use, not too noisy and the water helps keep the dust down a bit
Picking up some new bands this morning and then I will be getting the blunt blade onto the sharpener.

Silky oak is notorious for allergies and I lightly scraped my forearm while carrying a slab and it came up as a red welt. I hope it hasn't overly sensitised me to this wood as it can get so bad you cannot even touch it.


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## BobL (Dec 12, 2021)

Back on the big BS mill yesterday.
Cutting flats along the tops of logs for playground pieces.

The first two are of a Spotted gum. As you can see these logs are badly twisted so wouldn't make decent lumber anyway.
The mill was nearly maxed out in terms of cutting height. The throat is 36" but the max height of the band above the bed is 30" 
If I have to make cuts any higher than this I'll hav etc get out the CSMs.






The one below one is a Tuart, a very rare type of eucalypt no longer available in commercial qualities. It's a very hard wood and contains lots of tannins as can be see with the two black stripes across the log were I briefly stopped to add wedges. Water is used to cool/lube the band and the tannins in the wood reacted with the water and steel band to turn the wood black. Milling with a CSM builds up a hard black resin on the chain so diesel is sprayed on the chain to reduce this effect.

It's probably too good for a playground piece but that's what we're being paid for.


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## BobL (Jan 1, 2022)

Just when I thought I had the old BSM sort of sorted ,the Dipping and Rising in the cut is back with vengeance.
Last week while the boss was placing a big log on the mill with the truck crane (HIAB) when the log bumped the mill rail frame and one end of the rails came off the concrete base. I was really pleased it was not me that did it as I would not have heard the end of it. 

Anyway major exercise in fixing it as the mill had to be lifted off the the rails.


Rails lifted back onto concrete pad and re-levelled - this can take an hour or so but it only took about 15 minutes this time.
At this point two of of the wheels on the mill that run on the rails were found to be sloppy and we thought it might have been the bearings but it turned out they had 12mm diameter bolts through the 1/2" (12.54mm) bearing bores. So of to a bolt supplier to replace the bolts. But the new bolts wouldn't fit through the old bushes either side of the bearing so go home to bore these out on the lathe.

Then check all the mill geometry and back to Dipping and Rising. Tried out all the usual things, new blade, higher tension, more water, moved the gullets closer to the tyres, etc.

The boss is under pressure to get his lumber contract completed so I suggested we consider breaking up the big logs (there are not that many) with a chainsaw mill so they can fit on the smaller BSM. Given the amount of time we have spent messing around with the old BSM we would have done this by now

It's been really hot here, 4 consecutive days where its been over 105F and one day it reached 110F with a couple of days either side of 100F. I take medication that increases my possibility of getting heat stroke so I have been starting at around 7am and finishing up around noon (I am supposed to be retired!) and the going home and sitting/sleeping in air-conditioning.

As I was wrapping things up for the day I saw the boss dragging out his 880 with the 48" bar. Then he realised he did not have a chain so he was off to get one. I've offered use of one of my CSM (which are all at home) but he says he needs to get his sorted anyway as he has a log that is too big even for the big BSM to handle and wants to be independent of my gear.


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## Woodchuckr (Jan 1, 2022)

Leeroy said:


> Bob I hope you can get it sorted out. Bearings or blocks for blade guides?
> What WW stand for?
> Not sure this info on tensioning is relevant, but I've never heard of this method :
> 
> ...


They make great blades, lower tension than others run. Used them for years.


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## Woodchuckr (Jan 1, 2022)

BobL said:


> Just when I thought I had the old BSM sort of sorted ,the Dipping and Rising in the cut is back with vengeance.
> Last week while the boss was placing a big log on the mill with the truck crane (HIAB) when the log bumped the mill rail frame and one end of the rails came off the concrete base. I was really pleased it was not me that did it as I would not have heard the end of it.
> 
> Anyway major exercise in fixing it as the mill had to be lifted off the the rails.
> ...


You would be surprised how much tension you lose when blades heat up, Even with coolant. Wide boards and a wrong blade/dull blade and the problem just gets worse as you progress through a cut. Your wood guides probably make more unwanted heat. Myself I would get some good guides on it first and get it all aligned properly. 

These are good guides I put them on my first BS. If you pause the video at 1:27 you can see the adjustable scraper in front of the bearings to eliminate the buildup you were getting. https://timberwolfbandmillblades.com/proddetail.php?prod=TWGS03

When the BS cut straight at first was it on narrower cuts / smaller diameter logs?


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## BobL (Jan 2, 2022)

Thanks Woodchuckr I really do appreciate the input - even its just bouncing around ideas.


Woodchuckr said:


> You would be surprised how much tension you lose when blades heat up, Even with coolant. Wide boards and a wrong blade/dull blade and the problem just gets worse as you progress through a cut. Your wood guides probably make more unwanted heat. Myself I would get some good guides on it first and get it all aligned properly.


I agree - If I forget to turn the water on the tension drops off rapidly by 25% or more, and if its a green log steam can be seen coming off the end. The drop in tension is not surprising as I worked out the band will lengthen by about quarter of an inch per 100F rise in temperature. If steam is coming off the ned it must be over 212F so the band will have lengthened by about 1/2".

This mill has an hydraulic ram to tension the blade with a pressure gauge so I can clearly see what the tension is. I usually set the tension at 20,000psi and then warm up the engine (no cutting) and the tension drops off to 15,000 over about 20-30s seconds so I re-tension it back to 20-22,000 PSI. During a cut the tension drops off maybe about 1-2000 psi but I adjust that about mid cut and it holds true after that. I have tried cutting with the tension ranging from about 18000 to 26000 psi - no difference.

I run enough cooling water so there's no steam coming from the blade - band can easily be touched as soon as I stop. I will check the band temp tomorrow with my IR thermometer and will do that tomorrow,


Woodchuckr said:


> These are good guides I put them on my first BS. If you pause the video at 1:27 you can see the adjustable scraper in front of the bearings to eliminate the buildup you were getting. https://timberwolfbandmillblades.com/proddetail.php?prod=TWGS03


Yes they do look good. I note it says "*Note: The system must be blown out with compressed air after every 30 minutes of use.*" , well I certainly wasn't doing that on the old rollers.

I'm going to try and put the big roller guides back onto the mill. The mill came will wooden guides but the vendor told us that he had rollers somewhere . I was lucky to get the rollers because the seller didn't know where and took some time to find them.

I will try to convince the boss to spring from some new guides.



Woodchuckr said:


> When the BS cut straight at first was it on narrower cuts / smaller diameter logs?


When we first got the mill it had wooden guide blocks and it cut straight (wide or narrow logs) for about two years - then it started cutting crooked - I tried a zillion things and eventually it started cutting straight again. - I tried some narrow(12") cuts last week and it was not too bad but after the mill rail was moved it wouldn't even cut the narrow stuff straight.

Oh one more thing. Sharpening generates a small burr on the gullet. Is this likely to affect performance? I don't think is does because brand new blades with no burr behave just the same.

Thanks again.


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## Woodchuckr (Jan 2, 2022)

BobL said:


> Thanks Woodchuckr I really do appreciate the input - even its just bouncing around ideas.
> 
> I agree - If I forget to turn the water on the tension drops off rapidly by 25% or more, and if its a green log steam can be seen coming off the end. The drop in tension is not surprising as I worked out the band will lengthen by about quarter of an inch per 100F rise in temperature. If steam is coming off the ned it must be over 212F so the band will have lengthened by about 1/2".
> 
> ...


I don't think the burr affects anything, with the tooth set it probably doesn't touch the wood you are cutting just hits the sawdust. 
If you are absolutely sure the blade is correct for what you are cutting I would
Get a hold of the saw manufacturer and check it is all aligned to spec and ask what they think. If they are lined up proper and the right blade for the wood type and size is used it should cut pretty darn straight. Too high Blade tension or lack of tension from manufactures specs may pull your saw alignment out. When I first went to Sulfolk for their blades they advised me to tension the blades to their specs and then re check my saw alignment as they require much less tension than other blades which may throw your saw out of alignment. It sounds like you may have two things at play throwing you around. I am no expert but to me it sounds like maybe not quite the right blade and something out of alignment, and they amplify each other? Hope you get it figured out.


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## BobL (Jan 2, 2022)

Woodchuckr said:


> I don't think the burr affects anything, with the tooth set it probably doesn't touch the wood you are cutting just hits the sawdust.


That's what I was thinking.


Woodchuckr said:


> If you are absolutely sure the blade is correct for what you are cutting I would
> Get a hold of the saw manufacturer and check it is all aligned to spec and ask what they think.


Unfortunately there is no manufacturer. The Mill was purchased as a Used mill about 7 years ago from a miller who bought the pieces from different manufacturers in the US about 15 years earlier. 



Woodchuckr said:


> If they are lined up proper and the right blade for the wood type and size is used it should cut pretty darn straight. Too high Blade tension or lack of tension from manufactures specs may pull your saw alignment out. When I first went to Sulfolk for their blades they advised me to tension the blades to their specs and then re check my saw alignment as they require much less tension than other blades which may throw your saw out of alignment. It sounds like you may have two things at play throwing you around. I am no expert but to me it sounds like maybe not quite the right blade and something out of alignment, and they amplify each other? Hope you get it figured out.


Although some parts of the mill are not as rigid as I would like, the basic frame of the mill is built like a brick outhouse. I set all the angles with the band at 10,000 psi and then recheck it at 20,000 and there are no changes all the angles. 
Thanks for the suggestions.


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## BobL (Jan 3, 2022)

Today I swapped back to the old tyres on teh old BSM - these are wide and thicker so this meant repositioning the guide blocks and redoing tracking and general geometry - it all takes way longer than I like.

I also removed the burr on the inside side of the gullet ,of the same band I was using last week, using an angle grinder with a well used flap sanding wheel - slow but it worked well.

So, same blade - different tyres and burr removed.
Tried it on a 16" diameter, 8ft long hardwood log and . . . . . . 
Guess what - No diving! - just a long shallow rising cut in the cut! about 1/2" by the end of the cut.
The follower wheel guide block had been providing within about 1/2" of the gullets so I added a 3/8" spacer behind the guide block so support was now within 1/8" of the gullet.
Now the band dipped and rose about +/- 1/4" along the cut. 
ARRRGH!

The boss though it might be enough to break up big logs so I loaded this Brutus onto the mill.
It's an Iron bark about 40% harder than hickory.
The bark is thick and resinous and picks up loads of grit - genuine blade blunting material


I made one cut - same rising and dipping (mainly rising again) , blade started struggling - will need to peel the bark off along the cut and try again with a new blade tomorrow..

Meanwhile the boss (Jeff) and his daughter were churning out lumber on the Little Woodland.
I haven't been to the milling site for a few days but on New years day and yesterday Jeff was using his 880 chainsaw mill to turn logs into cants with.

Today they had that woodland working to maximum cutting capacity - this is Lemon Scented Gum - its also very hard



Here's Amanda doing her bit - she cut all the slabs on the sawhorses.


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## BobL (Jan 4, 2022)

This morning I looked carefully at the band I used yesterday and notices the left and right teeth sets were (a) "not much" (<20"')and (b) "not the same" - outside was ~ 5"' more than inside - this was weird because it was a new blade with maybe 2 dozen cuts on it.
Now it could be that something else being out on the mill caused this and maybe why the dipping and rising has being so erratic.
So I took a look at the other blades and in terms of set they were all similar.
Then I looked at the setter and sure enough it was also wrong!

So took a freshly sharpened blade, rejigged the setter and carefully set all the teeth to 26"'
Whamo - straight cuts at last!
The red Iron bark is really hard so I poured on the water.
I'm also using a reduced hook angle otherwise they band goes blunt much quicker.


The wood is very nice (although the log has a pukey centre)
The wood is going to be used for park benches - shame really because it will all go grey in the hot Aussie sun.



I easily squared up yesterdays wonky cut and made 3 squared cuts so it can go on the small mill.
Cuts were all quite good. The Boss is VERY happy as he now doesn't need to use the CSM.


I spent the rest of the morning resetting a bunch of blades.
I kinda kick myself for not checking this closely sooner.

Thanks to all who helped.


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