Old Corley Mill

[J_T]

 Fired it up for third try today. So far I learned dull teeth won't cut!! Put in 40 new chrome teeth.They were free so once they get dull I will worry about it then as all I have is a file. Trying it out in pine have 300 industral 6 cyl turning 1600 rpm blade 550 carrage speed one foot per sec seem to look ok but is my first mill to saw with most I know I learned here on the Forum but my memory is bad or I would of rembered to compare my teeth to a new one and saved my self some greif. So what you think to slow? ???

[Jeff]

I don't pay attention to feed rate by second or by the way its usually determined, by revolution. To many variables to say if you are to slow or too fast. I would think a foot a second is really moving though for an old saw.

You can easily check your feed rate by revolution. Look at your saw kerf pattern on your boards. You should be ablt to tell where it repeats. Saw teeth are never alike, so you can usually pick out the track of perhaps a damaged tooth and then simply measure the distace between its cuts to get your feed rate per revolution.  If you can't tell with your new teeth in, change one. Put in one with a nicked corner or somthing to easily tell.

[Ron Wenrich]

Feed rates are dependent on what you're sawing and how much power you have.  I listen to the saw.  When saw speeds slow down too much, your saw will lay over and give you a miscut.  Do it too often and your saw will heat up.  And you have the possibility of hanging the saw.

You shouldn't have too much problem in pine, unless your shanks are pretty thin.  If you feed too fast, then your gullets can fill with sawdust faster then it can be removed.  That will hang a saw.  

I'm assuming 550 carriage speed means your headsaw is turning 550 rpm.  I certainly hope you're not turning 1600 rpm on the blade.  I've never seen a mill turn that fast.  

I've run chrome teeth in the past.  You will never be able to file them on the first filing with a hand file, unless it is a diamond file.  You have to grind that chrome off of the face,   I always did this with a power sharpener, but you may have to take the teeth out and do it on a grinder (watch your fingers).

After the chrome face is taken off, you should be able to hand file the teeth, but it will be hard on files.  

[Fla._Deadheader]

I caught that 1600 RPM Blade also. 600 would be more like it????

[woodbeard]

Got me for a sec too, but if you go over it again, looks like:
motor- 1600rpm
blade- 550 rpm
carriage- 1ft/sec
Right,JT?

[Fla._Deadheader]

Score 1 for the "beardman". Sharp eye, George. I only had 1 cup before I read that!! :D :D

[woodhaven]

Sounds like you have a setup a lot like mine. You didn't give blade diameter or number of teeth. I run a 52" blade with 50 teeth at the same other specs as you. But by the book I run 3 1/2" per second carriage speed. I have everything on mine setup by the book, but the LOG and CUT is what tells you if you are doing something wrong.
Richard

[Tim]

Machinery's Handbook tells me that in my case a 48" blade can run upto 750 RPM. Seeing as we are considerably under powered, I  had my saw hammered a little stiffer with a little less dish. That way when the engine rpm drops, the saw isn't as quick to wander off.

I was told some years ago that rule of thumb is 4" of feed per revolution of blade or 250 fpm. I figured that to be basic insanity... mine feeds at 2.5 or 145 fpm. When I built my hydraulic carriage drive, I bypassed the flow control to allow the carriage to return at 4x the speed it advances. You don't have to hold the valve open for too long to get the carriage back.

I figure that if the cable ever broke on the return with a big pine on it, the carriage would come to a stop roughly halfway through the log yard...

While its well and all to quote numbers for feeds and speeds, its really my ear that tells the tale. Listen to your saw and engine if you have one. It looks to me that you are running your saw too slow.

[Ron Wenrich]

Tim

It looks to me that you are running your saw a tad bit too fast.  I'm running mine at 690 rpm and my saw doc tells me I'm at the upper limits.  Over 700 is supposedly hard to hammer and keep straight for very long.  Also, tooth maintenance is much higher at higher rpms.  

I've been around a lot of hand and circle mills.  Most guys are running between 520 and 600.  Some of the newer mills do 700,  You may be getting away with the higher rpm since you are running a smaller blade.  

Those book numbers may work pretty good in some woods, but I know I can't maintain that rate in black locust that's been left out in the woodlot for 6 months to a year.  It gets pretty hard.   :D

.

[Tim]

I have to run mine a little faster. Mind you the 700 is a unloaded speed. Because of the lack of horsepower an no flywheel, the blade looses rpm as I move into the cut (60-70rpm I'm guessing). I haven't had too much difficulty with saw maintenance. I normally get the two of them hammered twice a year, weather they need it or not. A change of bits lasts me 20-30 Mfbm unless of course I pile into a horseshoe or some *DanG thing.

Go Sens!!!!

[woodhaven]

Glad to see another circular mill owner !!!!  We are part of a dying breed I guess. I might make a little more saw dust than the band mills but I still haven't seem a band mill that can come close to the production, accuracy or consistency of my 50 year old mill. Ok so I can't pull my mill behind my truck and where it sits is where it will always sit. Now bandsaw owners go ahead and throw rocks at me.
I love this sit and will never leave just wish there more circular mill diehards out there.

[sawinmontana]

We own a small manual bandmill, bought it thinking we could make a little extra money. If we would have researched more we would have bought a circle mill. All we have here is softwoods, basically all you can sell is framing lumber. Even with the bigger kerf you would get so much more production. That would easily pay for the extra sawdust!!

[Tom]

Nope, we don't throw rocks :D

There's lots of ways of busting up logs and a circle saw sure has its place.  I like to watch them run too. There is nothing like the excitement one gets from standing next to big diesel engine humming along and V belts singing and flat belts slapping and the the saw zinging as it enters the log and hissing as the carriage is gigged back. Black smoke pouring from the stack as a hard spot is hit or the sawyer gets in too big of a hurry and the governor challenges the flywheel to catch up. Boards slapping to the conveyor and the high pitched whine of edger blades as the off bearers finish what the head saw started.

It's cool under the shed compared to outside because of the sap and water from the log being slung in a straight line down the mill, following the holes in the roof from lost teeth and the remains of tramp metal.  The sawyers clothes are drenched and his eyeglasses are covered with wet sawdust making you wonder how he can see the scale.

Then there is the end of the last log and everything is shut down.

Now, that's silence.  Have you ever heard anything so quiet?

Yep,  I run bandmills and can still enjoy a circle mill.  I can't throw rocks.

[woodhaven]

Tom
Everything you said sounds like you have been to my place. It is all very true. It is weird when you turn everything off and about 15 minutes latter you start hear again, your ears start to ring and all normal body functions come back. Sometimes I start it back up and just listen to the motor for a minute without all the other noise.
 You did leave out the bloody arms from log turning. Just thinking about it feels good.

[D._Frederick]

J_T,
Unless your 300 industrial is a big diesel, it seems to me that you are running it too slow. Running it at 1600 rpm would be just a fast idle for most engines. If your 300 six is a gas engine, running it at 2600-3000rpm would be more in the power curve range. If you are cutting any thing larger than poles, the extra power would help.

[J_T]

Woodbeard you got it right. It is a 50 in blade B pattern repalced all teeth and everyother shank. I am sure when I get to a god oak I will have to listen closer.It is a 300 Ford industral power unit gas. I had an oil rigger man do the math on pulley size. At 1600motor RPM the belt drive govonor holds the RPM right on I installes a donated sun tackso I could watch it. Wish return speed was faster but have a smallhydrolick motor driving a donated 6 ton power winch. Bought this old mill a year or so ago just now found my round tuitt.As you may of noticed this is a budiget operation. I either build it or beg it. :D Woodhaven one reason I got thi circle mill is I love to here them run another is a few folks seen this pile of parts and said I could never make it run.They never heard of the Forestry Forum. Get some odd looks when talking about a mill an say Jeff  or Frank or anyone of you said sompthing. They say how you know so many people? Thanks All 8)

[Tim]

It's amasing what you can do when you don't know its impossible eh J_T?

I've been running my circular for roughly 12 years and had thought about going to a bandmill  :-/ in the past. Production isn't as much of an issue as it was in the past as custom sawing is only about 5% of my business now. The biggest thing that was a detractor when it came to band mills was that most of the planers here won't accept band sawn wood. The other thing that turned me off bandmills was that I didn't want to get into professional walking...  ;D

[Corley5]

Glad to hear you got the old Corley set up and running.  I haven't had mine fired up yet this year but plan to saw some cherry over Memorial Day Weekend.  My saw turns at 500 rpms.  It's a 50" with 36 style 3 teeth.  My power plant is a MM 403 gas.  In top shape it'll put out close to seventy hp.  The way it's running now it's probably more like 50hp.  Rings and things are needed.  I'd like a band mill someday but will never part with the old Corley #5.  Nothing compares to the sights, sounds and smells of a circle mill.  I always spend some time watching them at old tractor shows especially when they're being pulled with steam.  Then I go on my way knowing that I can do the same thing when ever I want minus the steam power.

[dail_h]

 JT,
   Seems to me that a 300 six gasburner with a 50 in. saw is probably a little short on snoots for that kind of feed.Your saw speed may be a little high,maybe 100 rpms or so ,but that shouldn't cause to much trouble.You didn't say anything about a flywheel,so I asume you don't have one.That is always a help with light power.I agree that your engine speed is probably a little low,you might try speeding up the engine and refiguring pullies.I have the formula here somewhere if you need them.  

[D._Frederick]

JT,
I don't know what your oil rigger guy was thinking when setting the rpm of your 300 cube Ford engine, it is way out of the maximum power range. If it was me, I would get the torque curves for this engine and get pulleys to match the peak torque RPM. Your saw speed is on the high side for the power you have, it would be OK for a 220 Cummins.
For a mill to function correctly, you have to have the correct pulley ratios for the hp you have and the saw size.

[UNCLEBUCK]

hi everyone, most of you helped me get my old a.b. farquhar mill going late this winter remember !  i am using a 100 horse farmall diesel tractor and plug my hydraulic carriage lines right into the tractor and use the p.t.o and run at 425 rpm with my old 48 inch 40 tooth disston blade and i been sawing like a mad man !  i just pull the carriage lever and speed up the carriage so i get nice sawchips and not fine sawdust and then listen to the diesel outside the saw shed and just by listening and feel i can pretty much find the sweet spot now and its a bit different like with a 20 by 20 inch cant compared to a 8 by 8 cant, not much but i do slow down just a bit on the big stuff but never so slow that i start noticing that really fine sawdust, i never bothered to measure the feed because i dont seem to care, its when i hear the diesel start to snort and kind of leave it there until i am through the log, still saving for a new blade of same dimensions and probably have it hammered for around 500 to 540, starting out i didnt want to have everything screaming at me , plus i have a cable with pulleys that will shut off the pto at the back of the tractor and it hangs right next to where i stand and run the hydraulic levers and at anytime i can reach up and give it a tug and feel very safe with home made contraption, this is my first reply now as a sawyer with some good days under my belt allready ok !

[UNCLEBUCK]

another thing is that i have worn shanks and filed as much i could to get somewhat of a square shoulder,my teeth suck but i can cut about 10 big fat logs and then i just give them a quick filing and notice major horsepower improvements evertime, but the blade and everything else is cool after a long cutting session, one thing is that the blade was frying in the direct sunlight ,i mean you could fry eggs on it so i covered up the south wall of the saw shed and now i dont have to worry about the power of the sun causing the blade to wobble ,this old blade is stiff and straight as can be ! hope this might help you too ok !

[Frickman]

Unclebuck,

Glad to hear you are running an old Farquar mill. My one grandfather has one he bought off my other grandfather in the 70's. It is all wood and still like new. My other grandfather had bought the mill to get its International engine to put on his Frick. The Farquar is now run with a 671 Detroit that came from a WW2 landing craft. Needless to say, we've never run out of power on that mill.

You're doing good if you're learning how to saw by "feel". Every circle mill is different. We had one old Frick years ago that only my grandfather could saw on. It was getting pretty worn out and you had to know how hard to pull the stick to get it to saw. Fortunately that mill has been replaced.

Another thing I see you are learning is a circle mill is a system of components that must all work together. You have to get your motor set to turn the saw at the speed it has been hammered for. Then you have to adjust your feed rate to the diameter and species of log. The only way to learn is to keep sawing.

Along that same line, sometimes things work that you can't explain, and might contradict conventional wisdom or textbook knowledge. My saw has very little lead, maybe 1/32". The book says 1/16" to 1/8". I've tried that, no good. Set the lead back to just under 1/32" and it saws great. You might think the saw would rub the log on the gigback, but it doesn't. I can't explain it, and neither can my saw doctor.  I just leave it alone and keep running it. I also run my saw kind of slow, about 400 RPM's. My 471 keeps it running consistently though, so I don't have a alot of the problems you get when your saw slows down in the cut. My family has always run their saws slow, we have fewer saw problems and feel a little safer when running a stick mill.

Keep up the good work, and thanks for keeping another old circle mill alive.

Frickman

[UNCLEBUCK]

last thing for the night here,  i set the lead to 0 and the back of the blade was knicking the cant on the gigback so i just set the lead so it stopped doing that and everything was perfect, only made one initial lead measurement and the rest were trial and error, i read the lunstrom book so many times it feels good to have put it away for awhile but will probably read it again next winter, it was a good read ! goodnight ! :P

[UNCLEBUCK]

hello Frickman, i have a 671 with little hours on it and someday i be putting that on the mill, just read your article and found it very interesting and thought i was goofy for turning 425 rpm but i like it ! well i be catching up with the circular mill articles for the next week, i been busy ! take care