My lastest sawmill adventure- a Kasco Saw IIB

[Celeriac]

I've been rather absent around here for a while, just too many other things going on in life to tinker with sawing. However, recently a very nice lady donated her late husband's mill to the church camp. Last week we loaded it up and brought it out here to the farm for little repair and maintenance, before it departs for its new home. I've notice that there isn't much traffic about Kasco mills here, so I thought I would share the adventure. So without further ado, a couple pictures.







The saw is complete and runs. Before we moved it, we fired it up and noticed a few issues that needed attention, hence the guards, etc. are off in the pictures.  The mill is set up with a 10hp single phase motor for the saw and 12vdc feed motors for the carriage and head travel.  From all appearances the electric is a home built conversion,although Kasco offers it as an option. When I talked to the company rep today he said he could only recall three factory built electric mills being sold.

As for the repairs, the hydraulic tension indicator was blown, so I have it apart to replace the o-rings. The belt tensioner pulley bearing feel dry, so I'll replace it. The biggest discovery is the bandwheel bearings have a bit of "clunk and whir" to them, so they're slated to be replaced as well. They may last for years but it seems prudent to change them when the mill is close to home and tools. 

Quick question  ???  By my calculator, the saw runs about 4600fpm. Is that a good number? One blade manufacturer mentions running 5300-5700fpm on 18" wheeled saws. 

[mad murdock]

looks like a solid mill.  It will do the church camp well.  Soon there will be lots of building projects for young hands to get busy with!!   

[Larry]

I had one for 16 years and sawed a lot of lumber with it.  There are a few maintenance items that I might be of help on.

The hydraulic tensioner is a great little gadget.  The only thing that goes wrong is "O" rings.  Think I replaced my O rings a couple of times...a cheap fix.

Three styles of axle bearings and two sizes of shafts.  The first series of bearings used either a set screw or eccentric bearing locks...I think there was one that was a combination.  The last rendition is set screws, but you drill the shaft to lock the bearing.  The problem was the shaft was so heavy it would spin in the bearing.  The last bearing fixed that problem.  The latest shaft size is 2".  If you have to pull it apart for bearing replacement do both bearings and hope the shaft is ok.  Bearings going bad will cause intermittent broken bands.  If the mill is set up right a broken band is unusual.  Most bands died because they got too narrow from sharpening.

Power feed and up/down switches can be a problem and expensive.  I replaced my switches with drum switches from Grainger and they last for a long time.  Also wired in an override switch for reverse so I could gig back at full speed and not touch the rheostat.

Slow up can be fixed by wire brushing the acme screw and lubing with Pam...yeah the cooking stuff.  Once each day usually is enough.

The back guide bearings wear quickly.  Kasco has a new style that solve that problem but they eat up some of the throat width.  Think it was 29" and I used every bit on walnut crotch slabs so I never went with the new guides.

Only one log clamp is needed...two take extra time with no benefit.  Grind teeth on the clamp eccentric and make a longer clamping tool.

Ted is the go to guy at Kasco for problems and parts.

I always thought upping the fpm on the band would help but never tried it.  Most of the mills during the early 90's were set too run slower.

Bunch of pics in my gallery of my mill.

I listed a lot of stuff but if the mill is in good shape it will saw a lot with very little upkeep.

Probably forgot a thing or two so if ya need help hollar.

[Celeriac]

This mill only has 1-1/2" shafts, so I assume it's an earlier rendition. I don't see any signs of the shaft being loose in the bearing, but I don't have it apart yet.

I thought I read that the blade should not run against the rear guides during normal operation?  Is the "new" guide just a larger bearing?  If the existing guide prove to be problematic what about changing to something more like Cook uses?

Probably 2/3 of the blades were with the mill were broken, so that is a bit worrisome. Granted, many of them look like they were ground to a negative rake, which cannot help  :-\

[Larry]

Normally the band does run an 1/8" in front of the bearing.  When cutting heavy, dull band, or big knot the band can move back against the bearing.

I think the new Kasco guide is similar to Cooks and the rest of them right now.  Call them up and find out for sure.  Might make it lot easier on the installation.

[Celeriac]

Larry,
  What was your experience with blade tracking on your Kasco?  The reason I ask is that I am currently changing the main bearings and noticed the bandwheels are dead flat, no sign of crown anywhere. Conventional wisdom says a bandwheel should be crowned...

[Larry]

Just a guess, but I always thought the rabbet on the front of the wheel played a role.  In any case the saw tracked well.  It was very sensitive to band length...different brands would each track slightly different.

[Celeriac]

Well, the new bearings arrived. So I removed the idle side shaft. The tail end looked fine. Then I removed the bearing closest to the bandwheel...


Nuts!  

I need to disassemble the drive side to see if I'll be shopping for one or two pieces of steel.  The adventure continues!

[Larry]

I've seen that before and it is called expensive.  This thread address the problem and some fixes. 

https://forestryforum.com/board/index.php/topic,15696.0.html

[Celeriac]

Well, it's time for the latest update in the ongoing adventure of the Kasco.   I ended up ordering a couple pieces of 1045 TGP shafting from a local steel supplier, and then machined them as needed.  The wheels are pressed on and the drive pulley is in place. My next step is to put them back in the lathe to check the run-out on the wheel rim. If needed I'll take a fine cut to true things up. I'm still debating about adding some crown...

[zopi]

Put it together and run it...see how it tracks...hard to put the flat back if the crown doesn't work...
Some fine machine work there..

[JP135]

Man, I admire machine work like that. I'm following your progress.

[r.man]

Always a pleasure to watch a craftsman at work.

[timbuck2]

I've had a Kasco since the mid 80's and have experienced about all the problems you have found, shaft didn't get scored tho.  The concentric bearings were no good.  Keep the switches dry and you eliminate that problem.   Those mills were built when they weren't afraid to put the steel to them, very rugged and durable.  The guide bearings are available off the shelf from any bearing outfit.   One good thing about Kasco is that they are so simple in design that about all the parts are easy to find.  I added quick clamps made from reverse pipe clamps, makes edging alot quicker.  Good luck.   ps don't saw into the log stops!  ha ha

[Celeriac]

This evening I put one assembly back in the lathe to check runout, etc.  It measured about 0.0035"-0.004", t.i.r.  Interestingly, it did not read like the wheel was off center, more that it has warped over time. I should imagine that there was some stress in the casting and that it has relieved over time. 

Since it was already in the lathe I decided to take a light pass to clean things up. The setup was less than ideal as the whole shebang is pushing the limits of the lathe. It took a couple adjustments of speed and feed to prevent tool chatter.  One odd thing that I noticed is that the rim was not faced on both sides. The side with the green arrow is just as cast and runs out about 1/16". The other side, the one with the step, is machined. Methinks I will make a slight cut on rough side so the blade has even contact as the wheel rotates. I'm probably splitting hairs at this point, but some things always make me wonder  ???

Pushing the limits.


Not a textbook setup.


Green arrow is the rough side.

[timbuck2]

The steel on steel issue of the bandwheels has been debated to death, and at one time I considered swaping to, WM type wheels.  But I added a "lube tube"  a copper line that drips oil onto the bottom of the driver.  Doesn't take much and it keeps sawdust buildup off the bandwheels,  works good.  Every blade rides different on the bandwheels and the adj. needs to be tweeked.  An old band that has been pushed too long will crack.  You get a distinct thump sound and look out cause it will break soon.

[Celeriac]

I finally had a chance to get back to the mill. The band wheels have been trued up. The new bearings and shafts are installed on the mill, and I've gotten it to track when spinning it by hand. No idea how it will do under power.

The next thing on the hit list is the electrical system. When we ran the mill prior to removal it seemed to have an issue with the feed system. Today I opened up the control panel to find that the speed control rheostat is toast. Scrounging around online turned up a replacement. The one I ordered is a bit more heavy duty, and will be a close fit.

The adventure continues!

[Larry]

Since your in the control box I'll make a suggestion for you to think about.

Normal operation is to saw the board with the rheostat in the 2 to 5 range.  Saw exists the cut and you turn up the rheostat on high to return carriage.  Turn rheostat back down and repeat. 

I added a switch to bypass the rheostat on the return that works in tandem with the direction switch.  This eliminates the constant rheostat adjustment.  I don't know if it increases the rheostat life, but it sure makes sawing faster.

[Celeriac]

Larry, keep the advice coming.

Having read your earlier response, I purchased couple drum switches to replace the current toggle switches. I'm all about reliability as the mill will be located a couple hours from home and my tools.  I really like the idea of bypassing on the return, and had planned to wire is that way. Now, I'm wondering if there are times that one would want a slow reverse? Maybe that is provided by "armstrong''.

Do you recall what the correct blade length is for the saw?

[Larry]

If I wanted slow reverse I didn't flip the switch and the rheostat would be in the circuit as normal.  It is really hard to push by hand with the chain on the feed motor.

Band size is 13' 2" which is same as WM.

[Celeriac]

The bypass switch makes sense. I'll leave one of the original toggle switches in place and use it as the bypass.

Band size is 13' 2" which is same as WM.

Smart thinking on Kasco's part.

[timbuck2]

I had to re-think when I got my Kasco, and it was 1994, so that makes it about 17 years ago.  Still on the original switches and reo stat.  Was sawing today, some custom half round beams (faux), basically edged slabs, love selling that junk.   I keep all the good stuff and build with it, but always have too much crap left over.  I sell bundled "odds and ends" take all for $40-60 bucks, slabs and all.   All softwood, mostly W Pine, some Spruce/Fir or Cedar, I own the stumpage and timber.   .50 cents a BF is my cut off limit.

[Celeriac]

And now for an update on the ongoing saga. The wiring on the saw is a bit questionable, but I went ahead with installing the new rheostat on a trial basis. I figured it would be nice to know how things worked originally, before I start messing about.

Since the weather is turning brisk, we shoveled out a spot in the shop and deposited the mill there. Flat and level, without the drive chain connected, it was tough to roll the mill carriage. That seemed a bit suspicious as it should roll pretty easily, at least so it would seem. For kick and grins, I hooked up the drive system. The drive wasn't happy either and stalled when the rheostat was set much under full speed. The first step was to pick the carriage up off the track. Kerboing! The bottom sprang in a good 1/2". The wheels didn't seem to be rolling real well either, in spite of fresh grease. Further inspection revealed that the axle pins are we worn. Judging by the wear pattern, the excessive side force has been at work. I found some new bearings on ebay and ordered new axle pins from Kasco.



The other thing that we recently discovered is the saw could not reach its full height, as the motor hit on the frame, stopping everything at 22"-24", instead of the designed 30".
After studying it a while we decided to remove an added brace, weld some new iron to the frame, and then move the original brace. 

as it was


showing where the rub was


braces removed


new iron, ready for relocating the original brace


It may be worth mentioning that although Kasco did/does build electric saws, this saw was not electric from the factory. Hence some of the issues.

[stormyweatherman]

good luck and God Bless!  what a great enterprise to teach and share with others!  enjoyed the photos of your machining process.  where there's wood... there's a way :P

[Celeriac]

Today we finished up the iron work. After everything is assembled there is about 1/16" of taper in the frame, measured from top to bottom. Hopefully this is good enough.

Replacing the bearings and axles turned into a small adventure. Two of them fit correctly, and two were really tight. When assembled the tight wheels wouldn't turn. It turns out the axle pins were oversize by a couple thousandths. The solution was to chuck them in the lathe and sand off all the cad plating. After that the carriage rolled pretty smoothly by hand. Ten times better than before. The electric feed is still pretty cruddy in my opinion, and I'm not sure what else is to be checked or looked at. 

We dragged an old maple log out of the woods for a trial run of the mill. First impression- I wouldn't trade my Mobile Dimension for five Kasco mills.  The feed is iffy. The log clamping system is awkward and slow. And the blade tracking is questionable.  All of those opinions are obviously subject to change. On the plus side, it turned out some decent looking lumber; considering the questionable blade, junk log, and very questionable sawyer.

Band size is 13' 2" which is same as WM.

Wrong, in this case. On this mill the blade length is 12' 10", or 154".  A call to Kasco confirmed this. They said there are several different blade lengths, depending on the vintage of the mill. Apparently the saw we're working on is an early model and left the factory with 14" wheels. At some point it was upgraded to 18". They said the newer mills have a bit more space between the wheels, so that is probably where the 13' 2" length applies.

I must say that Kasco has been great to deal with when it comes to parts and questions. Called them on Tuesday to order the axle pins and they arrived Wednesday!

 

[Celeriac]

Well, better late than never, still working on the mill so I figured it was time for an update. After a bit of playing with the 12v motor system I felt that there had to be a better way of running things. The 12v system makes sense on an engine driven machine. With this mill being electrified the 12v was proving to be a pain. As it was setup there was a transformer to step down plus a couple diodes mounted on plywood. The setup worked okay but depended on the ground as a neutral, etc. which isn't right. To boot the 12v motor was struggling to raise the saw and pulling some 4x the rated full load current. I tried cleaning, oiling, greasing, but to no avail. It seems likely that in time the motor would give up the ghost, at $$$.

Through some searching and patience I came up with a 180vdc motor and controller to raise and lower the saw. I also found a heck of a deal on a 3 phase 230v gearmotor for the carriage. To drive the carriage I purchase a single phase in/three phase out variable frequency drive. All total the total expenditure is likely less that the cost of one replacement gearmotor.  Of course there has been some welding and machining but so far not too many conundrums. Hopefully I can get the wiring finished up tomorrow...

Here are a few pictures.

The new lift motor in place, not much room to spare!


Another view.


Carriage travel motor.


Overall shot, still needs to be wired up.


Thanks for looking.

[morgoon]

I never cease to be amazed at the talent around here

Amazing work!

[Celeriac]

My what a sweltering day! Hot out and warmer yet in the shop. I managed to get the drive in place, chain shortened, etc. and it looks pretty good. The new control panel is wired up as well. The VFD was a minor pain as every maker has a different idea of how the interface works, parameters are setup, etc.  I am mostly familiar with Allen Bradley and Benshaw drives so this ABB has a good learning curve. Learning is fun, but quickly becomes tedious when the temperature soars. The kinks came out after a few sessions of retreating to the house with the user manual.  There are still a couple issues that need resolved. The first being the speed control potentiometer stops at about 30%, but I guess that's to be expected from a $5 Radio Shack part.

One other change that may not be readily apparent is that the controls are now at a fixed height regardless of the saw height. Originally the controls traveled up and down with the saw. The idea of having the controls at knee height just didn't seem like a real ergonomic setup. I've also setup a limit switch so the carriage can return home and stop on its own. That's probably overkill but it felt like a good idea.

The drive motor.


The new control panel.


I shot a bit of video in an attempt to demonstrate how it works.

http://www.youtube.com/watch?v=nnh0IcBHw0A

[rmack]

let's see if I got this right...

you set out to tighten a loose bolt, ended up redesigning a sawmill? 

sounds familiar, nice looking craftsmanship too.

[Celeriac]

you set out to tighten a loose bolt, ended up redesigning a sawmill?

I suppose in a sense. The initial thought was that the mill is going to be 50 miles from home and shop, so it should be at minimal risk of issues cropping up. There were a few minor issues that needed attention, at that point the 'onion peeling' began, and this is the result. 

The one remaining issue that has me puzzled is the log clamping system as the factory setup seems awfully cumbersome. I did saw a couple logs and it was really tough to apply much force to the log. Trying to square the cant is a real challenge as the eccentrics don't apply enough force to push the log over tight against the 'knee'. >:( It took one guy with a cant hook to hold the log in position and another to clamp it.  Any good ideas out there?

[Larry]

Looks like a well thought out professional modification to me.

One suggestion while you're into the wiring.  Wire in a feed by-pass switch to return the carriage at top speed.  This will save cranking on the pot each time you return and your pot will be set for the next slice.  One of my better mods.

I don't have a real good fix for the clamps but maybe a small improvement.  I cut  "teeth" into the eccentric.  Once I had teeth, more force made it bite into the wood better.  I fabricated a 3' bar so I could really crank on it.  That would push about any size log up tight to the stops.  Also try to clamp with the log or cant in the middle portion of the eccentric.  Only one clamp is needed with the above mods....I repositioned it in the middle of the mill. 

[Celeriac]

Larry, how are the bunks supposed to be ordered?  Does this look like the correct order?

[Larry]

Found a picture.  Double bunks are on each end with the single bunk in the center with the eccentric cam. 

My double bunks look different because I welded stainless steel square tube to the top.  BTW, this allows cutting to within 1" of the bed.  The far double bunk has a toe roller in it also.  Laying to the right of the clamp bunk is my long bar to turn the eccentric.

[Celeriac]

 :(  Well, we got most everything buttoned up and gave is a whirl, what a wreck! Had a brand new blade on, made the opening cut, then on the return the carriage encountered a sliver the size of a clothes pin and promptly derailed the whole carriage. All four wheels off the track and on the ground, blade off and throwing sparks...    We got it back on track then tried a second cut- blade was shot... high amperage, etc.  Put the old blade back on which doesn't cut for beans, comes out of the cut an inch lower than it entered, etc.  Three cuts left a cake of sawdust and pitch on the bandwheels....

Just turned off the shop lights and called it a night. Back to the drawing board.

Not ready to give up my Mobile Dimension just yet!

[Celeriac]

The frustration continues.  >:( I bought a set of roller guide wheels from Cook and modified the guide blocks, etc.  (Pictures to follow...)  Anyhow, I set the guide for about 1/8" deflection and then went through tried to set the blade dead parallel to the track and such. The cuts on the test log are still a bit wavy and every cut is cupped/dished. A straight edge set across the log shows at least 1/16th dish...  Any thoughts on what I'm doing wrong... >:(

[ronwood]

Have you tried a new blade that has not been run before to see what happens?

Ron

[beenthere]

And also, what species of wood are you sawing?

[Ga Mtn Man]

Are you saying there's a cup across the width of the cut?

[Celeriac]

Are you saying there's a cup across the width of the cut?

Yes indeed, with a straight edge across a 12" cant there's a sixteenth dip.

After my previous post I did go check things over again and switched blades. With the new blade the cup disappeared, still a bit of wave though. The caveat is that the new blade is a different tooth pattern. The problem blade is a Lenox Woodmaster C, the blade switched to is a Lenox Chipsweep. I guess it would have been best to put on another Woodmaster to see if it's the one blade in particular or some geometry issue with that blade style  ??? 

I have to admit that the mill is beginning to frustrate me a bit. Naturally one hopes everything will run like a charm, but alas it never does. From what I've read here on the forum it seems that band mills are a bit capricious when it comes to blades, possibly more so on smaller mills such as this one, everyone seems to have a different brand, set, rake, & etc. that works best for them. So I suppose it's safe to say that I am now starting that journey with feet dragging.

The log is maple.

Here are a few pictures, firstly the new roller guides.





The wiper/lubricator. It's now plumbed into a drip lubricator. The wiper is something I welded up. It's packed with felt.



This is the blade that was giving me fits with waviness and dished cutting.



This is the Chipsweep, which worked pretty good to finish out the log.



This is the cut left behind by the Chipsweep. There is certainly a lot less dust left in the cut as compared to the other blade!




The journey continues...

[customsawyer]

I have never seen a blade like that last one. The cut that it left is very rough. I hope you get it straitened out. In the pic that has the belt in it, is that your drive belt? If it is then it might be slipping on you some which will let the blade slow down. It will cause the waves that you are fighting.

[Celeriac]

For a bit of background, someone donated a Kasco Saw II to the camp. We pretty much rebuilt the saw, installed roller guides, etc. https://forestryforum.com/board/index.php/topic,52911.20.html

The good is that the saw is wired up at camp, the bad part is that I cannot cut decent lumber which is getting frustrating. Nothing like a two hour commute then spending the day fighting with something that should work better than it does! 

The saw's main issue is cutting consistent lumber. The saw seems especially prone to dive. The dive seems related to feed rate which is another part of the frustration- I would think that with 10hp electric the saw would run out of power but I cannot get close to full amperage without the cut quality going out the window. At a feed rate where I can hold a fairly straight line the kerf is filled with fine sawdust, which I would think indicates the feed speed is too low. Up to a decent feed rate and the wild cutting begins. The wildness would appear to be related to the pressure against the blade as I need to back down the feed considerably as the saw dulls. Last time I managed to get a couple hundred bd/ft of maple before I gave and changed the blade. The last fresh blade gave me fits on the first log while cutting 6" boards. I caught it starting to dive, cut the feed rate a bit, and it came back up to level.

I've gone through setting the blade parallel to the line of travel. I've experimented with blade tension and have been running higher than what is recommended by Kasco. Without some way to check the actual blade tension I'm hesitant to up it, more so if there's a mechanical problem I am missing.

Any suggestions of what to check or tweak. Right now my only thought is to try angling the blade up a bit...

-Aaron

[beenthere]

Aaron
Sorry to hear about the woes.
Would be nice if you had continued the old thread, because there may be some clues to help sort out where you are at and still having problems.

[Happycamper]

Celeric,
  I'm not the pro on the forum but it sounds to me like lack of SET in the blade. That has been my experience.I'm sure the pros will chime in soon.
                                       Jim
               

[Celeriac]

Aaron
Sorry to hear about the woes.
Would be nice if you had continued the old thread, because there may be some clues to help sort out where you are at and still having problems.

I was going to do that but it popped up that it had been too long and I should start a new thread.

As an added note it seems to be doing better at cutting White Pine, so perhaps too much set? The blades I've been using are new Lenox. I'm about out so thinking about trying another brand.

[47sawdust]

Aaron,
My first mill was a 1997 Kasco IIB.I replaced the original blade guide bearings with greasable bearings from Kasco,did a blade alignment and it cut great.I ran Timberwolf  10 degree blades at high tension.I don't remember the exact tension but it was close to 2100#.It was powered by a 20 hp  B&S Vanguard,Great engine.The quality of the lumber I sawed was excellent.The up/down and travel speed were a rather glacial pace and I'm not getting any younger.
I hope this helps,Kasco was always there to help.

Mick

[Celeriac]

Today I orders some Munkfors blades from Menominee Saw. Once those arrive I'll take another crack at getting things figured out and squared away.

[EZ]

I been using munkfors blades for 12 years and they are the top of the line blade for me.
EZ

[scrout]

Celeriac,
My Lynn design puts bottom of the roller guides 1/4 inch below the bottom of the band wheels for better blade control.  Yours look to be the same height?
Also, my 1 inch diameter hydraulic tension set point is 2300 psi for a 1.25 inch wide blade.


 

I also have a makeshift (ghetto) automatic electric carriage setup made from a HF router speed control, battery charger, and HF winch.  Actually works ok, but if something goes amiss, like you run out of gas, the HF winch will break things if you don't get it shut off immediately.  Ask me how I know....does you VFD have a programmable torque limit?

[Celeriac]

Well I expect it's time for an update of the ongoing tribulations with this mill. Now that we're back to sawing the problems continue, the chief of which is the blade wanting to dive when taking a decent cut. I figured the mill would run out of power, but sadly I cannot get anywhere close to full load without everything going to ruin.  >:(

As I set the mill up originally the guides did put a bit of down deflection in the blade. This week I cut some 1/4" spacers which I used to space the guides down. This helped but the mill was still prone to dive. We checked the blade for parallel to the travel, etc. and everything looks fine. Trying to keep frustration from turning to rage I kept puttering at sawing. After lowering the guides I observed that the blade dive is only occurring on one side of the cut, that being the side with the movable guide. In addition the dive seemed to be related to force against the blade. So we proceeded to start wiggling, tugging, and pulling.

It appears there is a lot of flex in the movable guide. So my theory goes- as the movable guide starts taking the thrust of the blade it pivots backward, which in turn inclines the blade downward into a dive. This would explain why when slowing the carriage to a creep one can sometimes get the blade to come back inline. 

Now the question becomes why did this show up? Do they all do this? My conjecture is that the original Kasco guide setup has the blade pinched between two rollers so even if the blade tries to dive it is contained. By me switching to roller guides there is nothing to hold the blade other than alignment and the bit of pressure from the guides being lower than the wheels.

So how to fix the guide flex? Next time I go to camp I will take a dial indicator to pinpoint what is flexing. From visual observation it appears perhaps the rods the guide travels on are flexing. If that is the case I don't know of an easy solution short of spending a grand on Thompson linear stuff.  Time to put on the thinking cap. ???

The other thing tickling my brain is the lack of crown on the bandwheels. The Kasco wheels are dead straight so in essence the guide has to take the thrust load of the blade. Would crowning the wheels significantly reduce the load on the guides?

Thanks for listening, and any suggestions are certainly appreciated.

-Frustrated in Ohio.
aka Aaron

[47sawdust]

I did purchase new greaseable blade guide rollers from Kasco for my IIB,also I purchased urethane belts from Suffolk Machine and had a machine shop mill a v-groove in the wheels.3 years of sawing with no problems.You must be very frustrated.Good luck ,Mick

[backwoods sawyer]

Crown on the wheel is hard to see with just the eye, Take a new razer blade and stand it up on the wheel there should be an equal sliver of light on each side, if not a machine shop can grind a .008 crown on them as steel wheels do wear down. 
Ussualy when the saw wears the grind marks off the wheel you are about halfway to needing them crowned again.

take a look a the saw guide arm on the Cooks mill if you have to rebuild, simple and solid.

[Celeriac]

The wheels on the mill are definitely flat. My understanding is that they were flat from the factory.

Until proven otherwise it appears the guide arms aren't the problem,  rather the traveling rails that adjust the guide.

I will do some additional sleuthing next time and report back.

-Aaron

[36 coupe]

This mill only has 1-1/2" shafts, so I assume it's an earlier rendition. I don't see any signs of the shaft being loose in the bearing, but I don't have it apart yet.

I thought I read that the blade should not run against the rear guides during normal operation?  Is the "new" guide just a larger bearing?  If the existing guide prove to be problematic what about changing to something more like Cook uses?

Probably 2/3 of the blades were with the mill were broken, so that is a bit worrisome. Granted, many of them look like they were ground to a negative rake, which cannot help  :-\

Back when the Ross Band Mill came into use around here I got a used blade from a fellow.There was no resharp service here.I thought my Belsaw Sharpall could be used to sharpen band blades.One thing I noticed was the face of the blade was not at 90 degrees.The blades were sharpened and then set.I think this puts a negative angle on the face of the tooth.A dealer I talked with said the blades had to be sharpened right out of the box to cut well.I had put a 5 degree face bevel on hand and power rip saws when I sharpened them.They cut faster and went longer before dulling.The blades for the Ross mill came from Simonds.I gave up the Belsaw idea because there was not enough headroom in the sharpening shop.I do think that grinding the entire profile of the band saw blade is a waste of time.The face and top of the tooth do all the cutting.Photos Ive seen of band mill blades show deep scratches in the gullets.Grinding with too coarse a grit and grinding too hard is hard on saw steel.

[ozarkgem]

I had the same problem with my Mighty Mite . The blades would dive and cut lousy boards. The factory couldn't help. The guy I bought it from changed the bands wheels to all steel. I read a article about how the wheels needed crown. I checked mine and they were flat and sloped. I took them off and put on pulley wheels with V belts and ended the problem. Just a a thought