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Circle mill theeth

Started by captain_crunch, December 21, 2012, 11:44:46 PM

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captain_crunch

Never changed theeth on mill got bunch of old ones  What is difference between tooth marked H and one marked e ??
M-14 Belsaw circle mill,HD-11 Log Loader,TD-14 Crawler,TD-9 Crawler and Ford 2910 Loader Tractor

Ron Wenrich

That's probably a manufacturer mark.  I know that Simonds have an S on them.  H is probably for Hoe.  Can't help you on the e. 
Never under estimate the power of stupid people in large groups.

bandmiller2

Cappy,just for chuckles put a new set of bits in,and see the differance.Its human nature when fileing to get less and less hook.The bits get short and stubby and pull hard.I don't swage my bits when they get filed down just replace them.My old Diston saw is anouther story they will have to be swaged and reshaped as long as possible.Most folks don't think of it but hook is very important especially with smaller saws.A big log with a small saw the tooth actally comes down flat and has to punch out the wood insted of cutting like a sharp chisel.Of course its nice to get the max mileage out of a set of bits.Have  good holidays my friends. Frank C.
A man armed with common sense is packing a big piece

Ron Wenrich

I've always found that short teeth didn't stay sharp as long.  From an economical standpoint in a bigger mill, it made sense to take them out when performance started to lag.  The cost differential was made up in the better production rates.
Never under estimate the power of stupid people in large groups.

captain_crunch

Proably will be like a power saw chain not realizing how dull it was till you put a new one on ::) ::)
M-14 Belsaw circle mill,HD-11 Log Loader,TD-14 Crawler,TD-9 Crawler and Ford 2910 Loader Tractor

bandmiller2

Wile we're talking bits,has anyone here silver braze carbide to worn out mill bits.I'am thinking for saws Like Diston where bits are no longer available.Possibly a simple fixture to hold the bit in a milling machine to cut a seat at the proper angle then silver braze a tip on or even stellite tips.Its done all the time with swing mill saws. Frank C.
A man armed with common sense is packing a big piece

circlesawn

Hey captain - in your collection of bits, you don't have some H4½'s do you?

I have been hunting for the old 4½ bits with no luck.  I have called several saw shops and the answer I get after a lot of laughter is "they were obsolete 15 years ago".

I have entertained Frank C's idea of cutting down my old bits and setting a carbide insert.  It would be interesting if anyone has done this before?

Ron Wenrich

I like that idea of cutting them down and putting in carbide.  It would probably be a little pricey at the outset, as you would have to grind down the teeth.  But, it would be cheaper than buying a new blade.  And it keeps those old blades running.

You might have to take them to a machine shop to get the original grinding to the specs you need.
Never under estimate the power of stupid people in large groups.

bandmiller2

Silver brazing carbide bits is quite easy.Being "frugal" I've rebuilt many hammer drill rock bits.Their problem is they wear in their diameter and bind.I cut the worn end with a wizzer wheel and slot it also,braze in a new spade tip carbide and back in business.Sawmill bits are only file hard and could be cut with an endmill.Make a fixture to hold with a de-stako clamp, lock the tables and mill them all the same. Frank C.
A man armed with common sense is packing a big piece

bandmiller2

I'am not interested, but this could be a good part time business for the right person, advertise on the forum and tip and retip orphan bits. Frank C.
A man armed with common sense is packing a big piece

GeneWengert-WoodDoc

It depends on your mill and the saw, but many saws are made initially with too many teeth.  So, when putting in new teeth, just replace every other one.  The old, short teeth will not be doing much work and the new teeth will take a bigger bite in many cases (0.11" is ideal) which means less fine dust and better sawing overall as the blade will not be so hot.  As you may know, all the shanks must go back into the identical spot where it came from, so always replace one tooth at a time.
Gene - Author of articles in Sawmill & Woodlot and books: Drying Hardwood Lumber; VA Tech Solar Kiln; Sawing Edging & Trimming Hardwood Lumber. And more

Ron Wenrich

That's because a lot of mills are underpowered or are spinning too fast for the feed rates. 
Never under estimate the power of stupid people in large groups.

Jeff

As Ron said. The blades are certainly not made with too many teeth, however some blades may not be able to saw efficiently in the application which they are placed. Removing every other tooth on a saw that is tuned correctly for the mills horsepower and RPM is not something I would ever do unless I was desperate for some unknown reason.
Just call me the midget doctor.
Forestry Forum Founder and Chief Cook and Bottle Washer.

Commercial circle sawmill sawyer in a past life for 25yrs.
Ezekiel 22:30

GeneWengert-WoodDoc

I do agree with Ron.  That is, the circular saw on the mill was designed without respect for the mill's rpm or horse power.  A manufacturer makes a saw for the worst situation and this turns out to be a saw with too many teeth for many mills.  If you want to find the correct tooth spacing for a particular mill, see Stan Lundstrum's book Circular Sawmills and Their Efficient Operation...free download PDF at www.fpl.fs.fed.us/documnts/misc/circsaw.pdf

I have seen many circular mills go with every other tooth spacing.  I have seen band saws remade with this as well.  It does indeed work well for many mills, especially under powered.
Gene - Author of articles in Sawmill & Woodlot and books: Drying Hardwood Lumber; VA Tech Solar Kiln; Sawing Edging & Trimming Hardwood Lumber. And more

Jeff

I think its a real stretch to be recommending removal of every other tooth without knowing any specifics on any thing about the mill it is being recommended for, but I guess my view is coming from a guy that never had less than 100 hp to work with and 10s of thousands of hours in the cab.
Just call me the midget doctor.
Forestry Forum Founder and Chief Cook and Bottle Washer.

Commercial circle sawmill sawyer in a past life for 25yrs.
Ezekiel 22:30

bandmiller2

When we're talking circular mills we really need to branch off into two groups,high speed production mills and the rest, older handset mills.Production mill have the horse power to utilize high tooth count saws at a high feed rate.Belsaw on the outher hand is at the oposite end designed for low power slow feed,therefore with few teeth on the saw.If you have an old underpowered mill and a saw bristling with many teeth,you have a mismatch,you will  have to ether feed very slowly or better cut with every outher tooth as suggested.It would be unwise for a production mill to use an saw with few teeth as it would limit there feed rate. Frank C.
A man armed with common sense is packing a big piece

CCC4

What about marking the lumber? If one tooth missing, or if there are broke corners, marks are left.

Jeff

That's why I'm saying you can't say that unless you know the mill, and just because it is a circle mill under a shed somewhere does not mean its not a high production mill. We have some Amish mills around here running old mills with big time diesel power plants that would laugh if you told them they could saw more efficient with half the teeth. Pretty tough to make a blanket statement like that.
You should not have any marks if you remove the teeth.
Just call me the midget doctor.
Forestry Forum Founder and Chief Cook and Bottle Washer.

Commercial circle sawmill sawyer in a past life for 25yrs.
Ezekiel 22:30

Ron Wenrich

There's not too many mills that can utilize all the teeth.  The manufacturers of saws often sell....teeth.  I was running F pattern teeth, but moved to a saw with fewer teeth and a B pattern.  The B pattern gullet can handle 1½ times the volume of an F pattern.  I gained by going to the B pattern.

I was running 710 RPM.  At that speed, saws are hard to control as effectively.  After doing some rudimentary math, I found that to efficiently use a saw at that speed, I'd have to feed at 260 ft/min.  You can attempt that if you like.  It doesn't work in hard hardwoods.  I cut the speed back to 640 with no fall off from production and better saw performance. 

The problem with most millers is they buy saws from guys that peddle saws and teeth.  They don't know a lot about mills, in many cases.  They do know what other guys are using, and even though its not the right saw for the right situation, things become mill standards.  In my area, most circle mills use a 50 tooth F pattern saw, anywhere from 52-56".  I ditched them years ago.  If you buy a new saw, you can tell them how many teeth you want in it.  Guys that can't afford enough horsepower to spin a standard blade usually can't afford a new blade.  So, they buy used stuff.

If you go and put short teeth in every other tooth, you have to lower your feed rate.  Of course, you could lower your feed rate and keep all the teeth in there.  I know, lower feed rates make finer sawdust.  If your shanks aren't up to snuff, you'll get seepage. 

Another factor to figure is that eventually your long teeth will be as short as your short teeth.  You'll never reach a happy medium.  I also know that I can tell when I have even one tooth that is bad on a saw.  It can be just a little dull, or it can have just a little nick in it.  The saw doesn't feed the same.  I've had a few where I've put a short tooth in for one reason or another.  It doesn't saw the same, but gets you through a pinch.  Running every other tooth is just a band aid for another problem.



Never under estimate the power of stupid people in large groups.

Jeff

We tried a B pattern saw on the CMC but it just could not feed like the 56" and 60" F. We were running 150 electric Hp at the headsaw, 75 on the vertical edger and 75 on the hydraulics. Even with that kind of horsepower, like Ron says, I could tell when one tooth was gone. Occasionally I'd have a tooth break right off, and the saw would just not be quite right.  We sawed probably 80% aspen on the east mill and 20% mixed northern hardwoods, predominantly Red Oak, Hard and soft maple, and a mix of everything else. The west mill was 100% mixed northern hardwoods. In aspen I could get 6-7 inches of feed per revolution, just a little bit higher than the .11, and other hardwoods, depending on the species, around 5.
Just call me the midget doctor.
Forestry Forum Founder and Chief Cook and Bottle Washer.

Commercial circle sawmill sawyer in a past life for 25yrs.
Ezekiel 22:30

GeneWengert-WoodDoc

The neat thing about my initial suggestion is that the person can replace every other tooth and try it out.  If they do not like it, then replace the remaining teeth. And nothing has been lost.

It is true that as the new teeth wear, the old, short teeth will begin to work again.  It is at this point that the operator has to decide if a more permanent change in teeth is worthwhile.  Note that you cannot just remove every other tooth and shank in a blade, as that will change the tension and will create wobble.  You could remove teeth just before retensioning however.

I used to manage a mill with a 54", 56" and 60" blades.  We had the 60" cut down to 48" as that blade was hard to keep running straight.  we had 150 hp at the headrig so we were not under powered using F and 2-1/2 style teeth.  we used Standall bits in the winter and started keeping them in all year.  We did keep all the teeth in the saws as we were not under powered and were cutting small-ish diameter log much of the time (under 20").  As part of my job at VA Tech, I would visit hardwood sawmills and assist in diagnosing problem, improving equipment efficiency and improving operator skills and efficiency for the past 30 years.  For many years, I would work on 40 to 50 different mills a year.  So, it is from this background that I suggest trying wider spacing of the teeth.  The difference in many mills, band and circle, is amazing.

As an added comment, I find that many inserted tooth saws do not have any attention paid to side dressing...a fancy term for making sure all the teeth protrude the same amount on each side of the blade.  The protrusion is best measured with a goal of no more than 1/100" variation.  Sometimes, we found that teeth right out of the box had different tip widths, so some repair was needed before a tooth could be used.  With good side dressing, the lumber's surface will be quite smooth and subsequent planing allowance can be reduced.  If this is reduced, then potentially sawmill target size can be reduced, plus the sawdust volume can be reduced (15% of log volume is sawdust with F or 2-1/2 style teeth)...overall, more lumber per log.
Gene - Author of articles in Sawmill & Woodlot and books: Drying Hardwood Lumber; VA Tech Solar Kiln; Sawing Edging & Trimming Hardwood Lumber. And more

captain_crunch

That kinda answered my question The teeth I have are not brand new but lots left compared to what is on saw now The ones marked H seem to be about 1/32 or  less wider than the ones Marked E at aprox same length so if I dress sides the same they should work ??? ???
M-14 Belsaw circle mill,HD-11 Log Loader,TD-14 Crawler,TD-9 Crawler and Ford 2910 Loader Tractor

Jeff

Do you have a spider guage?
Just call me the midget doctor.
Forestry Forum Founder and Chief Cook and Bottle Washer.

Commercial circle sawmill sawyer in a past life for 25yrs.
Ezekiel 22:30

captain_crunch

Jeff
Not sure what that is I was going to use micrometer and hopefully by putting them in machinest vise should be able center them with narrower tooth to get them even. Have not dug thru all of them yet so may have enough of one size. Sounds kinda red neck but they are too good to let them go to waste ::) ::)
M-14 Belsaw circle mill,HD-11 Log Loader,TD-14 Crawler,TD-9 Crawler and Ford 2910 Loader Tractor

Jeff

You need something to check your side clearance once the teeth are installed. measuring the tooth width before they are installed, really won't give you what you need, and the discrepancies in width can come from the way the tooth seats in its socket. I have a couple of different styles laying right here on my desk. You could make something to do the same thing



 

This photo shows the clearance for this particular gauge. 3 "legs" would be flat on the saw plate, and you can slide it around to find the teeth that exceed the clearance on the gauge.



 
Just call me the midget doctor.
Forestry Forum Founder and Chief Cook and Bottle Washer.

Commercial circle sawmill sawyer in a past life for 25yrs.
Ezekiel 22:30

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