iDRY Vacuum Kilns

Sponsors:

Band saw blades vs circle saw blades

Started by Arkyrick, February 13, 2017, 08:28:05 AM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

Arkyrick

I am curious ??? I use lots of blades on my WM mill (lots of blades) how long do circle saw blades last?
LT 35 hydraulic portable "73"Ford 335 tractor - lots of chains

Bert

The blade itself will last indefinitely. Ive never had one "wear out". The bits and shanks are replaceable. A set of bits (about $160) for my saw will usually last 100-150 thousand BF of lumber sawn and thats with no debarker. About 5000 ft between light sharpenings.
Saw you tomorrow!

paul case

They have changeable teeth. The blade can last a long time but the teeth must be kept sharp just as with bands. A friend of mine who probably cuts 15000 feet a day on his circle saw sharpens it before he starts and at lunch break.

That is a 48'' circle blade. I am not sure how much mileage you would get on a lucas blade or other smaller circular blades.

PC
PS. I have been beat to the punch.
life is too short to be too serious. (some idiot)
2013 LT40SHE25 and Riehl edger,  WM 94 LT40 hd E15. Cut my sawing ''teeth'' on an EZ Boardwalk
sawing oak.hickory,ERC,walnut and almost anything else that shows up.
Don't get phylosophical with me. you will loose me for sure.
pc

Ron Wenrich

Depends on what you hit.  I had ones last a really long time, but sometimes things happen that will wreck a saw.  Nails usually aren't a big thing.  1/4" galvanized is a big thing.  If you rip off a shoulder, they can weld on a new one.  Bottom line is that if you're rough on your saw, it won't last as long.  But, I have heard of guys getting 20 MMbf on those saws.  A lot depends on what you saw.  I only wrecked 1 saw in over 50MMbf on the above mentioned 1/4" strap steel. 

There is periodic maintenance that does need to be done.  I always changed shanks once a year, usually before things froze up.  Shanks will get thin, and they can be sharpened.   Shanks run about $7-8 apiece, and you should get about 2 MMbf on them sawing hardwoods.  You'll also need to get periodic hammerings on the saw.  Generally runs about $100 and I did mine when I had the shanks replaced or needed to get a repair due to trash metal. 

I haven't bought teeth in a long time.  I thought a box of bits was $150, and I could replace the saw bits twice on that box.  I only got about 50-75 Mbf on a set of bits before my production started to drop when the teeth got too short.  For me, it was cheaper to put in new bits than to spend more time sawing.   I generally sharpened at quitting time and at lunch time.  Sometimes you would have to sharpen in between, depending on what you were sawing and the time of year.

I ran a cost of sawing on a band mill vs sawing on a circle mill a long time ago.  It seemed that the $/Mbf was much higher on the band mills than on the circle mills.  Saw costs were less than $2/Mbf.  That included buying a new saw and all the bits, shanks and hammerings that went into it. 
Never under estimate the power of stupid people in large groups.

Darrel

On my old LT40, I saw about 1,500 bf per sharpening. But you have to understand that I saw mostly blue Pondarosa pine and the bark is knocked off very easily. I sharpen and set my own bands so sharpening costs are very low for me. I buy a box of 15 double hard bands for about $340.00 I average 12 sharpenings per band. 1,500 bf X 15 bands X 12 sharpenings = 270,000 bf per $340 box.  Of course you have to figure in bands ruined if I hit iron, but that doesn't happen often.
1992 LT40HD

If I don't pick myself up by my own bootstraps, nobody else will.

Percy

When I was working my lt70 alongside my sons 10 inch Peterson swing blade, my blade costs were higher than his. Can't remember the numbers but if either of us didn't hit any steel or nuggets, the savings for the Peterson was significant.
GOLDEN RULE : The guy with the gold, makes the rules.

Darrel

Percy, were you sharpening your own or paying to get them sharpened?  Most sawyers on circle mills sharpen their own and most band mill sawyers send theirs out. So this is also something that has to be factored in.
1992 LT40HD

If I don't pick myself up by my own bootstraps, nobody else will.

Ianab

Even sharpening your own bands has a cost. You need a band sharpener, and you spend "work" time doing it.

On a swing blade you sharpen on the mill in a few minutes. Comparable time to swapping out a band? It's actually a nice break to sit down under the mill and touch up the blade after a couple of hours work.  :D Drink of water and a sandwich, and you are back into it.

If you hit metal, then bad things do tend to happen, just like a band mill. Depends exactly what you hit, sometimes there is almost no damage, other times it can be sharpened, or you are only down one tooth. Worst case is that you shatter all the carbides. Then it's blade swap time, put a spare on, and get that one re-tipped. It's hard to wreck a blade completely because you are pushing it by hand. Even if you hit a rock or porcelain insulator that stops you dead, it's obvious that something has gone wrong, and you back out. You don't have the momentum of the log and carriage like a large circle mill, driving the rock and blade into each other.  You might mutter some bad words, but it's not a disaster. Cost is comparable to hitting the same rock with a band and ruining the band.

In normal sawing you get dozens of sharpens (at minimal time/cost) before the cutters are worn down. Then you are up for a re-tip, costing similar to a new band,

The blades are relatively expensive, but you should get years of service out of them.
Weekend warrior, Peterson JP test pilot, Dolmar 7900 and Stihl MS310 saws and  the usual collection of power tools :)

longtime lurker

Costs me $99 incl tax to retip and hammer a Lucas blade which includes freight costs. I could braise them on myself for 1/3 that but I'd rather saw more log and let a sawdoctor do it.
Costs me $550 incl tax to retip and hammer one of the 42" saws, including freight costs.
Sharpening either we do in house... Maybe 5 minutes for the Lucas and 20 for the 42". We mostly run TCT but there's a couple species where I'll swing to stellite.  I got plenty spare blades for both.
Insert teeth have never been popular here.

The maths here is real simple. When you compare apples with apples the kerf saving on a thin band bandmill only makes more money if your cutting "highly valuable black walnut" or similar species in 4/4 or thinner thickness. In species where log cost is lower, or in the premium species if cut at 8/4 or thicker, the extra recovery mostly gets eaten up by the band maintenance costs. In short its more profitable to make more sawdust with a circle saw and put the money saved on bands towards buying more logs. Circle mills ( remembering apples with apples) will mostly run rings around a comparable bandmill with regard production per man day which is a big part of that equation.

In premium species that all goes out the door.

A lot depends on cut patterns etc but backsawing I never fret the kerf loss. Any "gain" a band would make except in real big logs comes as low value pith or shorts, and its negligible.
Quarter cutting I lose around 15% in real world recovery with the circles compared to a band which does give me pause for thought: I've been tossing around either a band resaw or sash gang resaw for a while.
The quickest way to make a million dollars with a sawmill is to start with two million.

Chop Shop

I love my circle saw.  I hate my bandmill.

The kerf argument is only important to bandmill guy trying to sell a job.   

I can cut circles (nice pun huh? lol!) around a bandmill.   popcorn_smiley

longtime lurker

I think scale of operation is a big factor in that.

Sometimes I'll sit for a month running  nominally quartersawn flooring stock. We run circle headsaw and circle resaw like most Australian hardwood mills.
Flitches hit the resaw unsized, and you carve off inch boards till there's not enough left for an inch board and get left with a "dog board". If its thick enough we take a 3/4" board that goes for panelling stock, otherwise it feeds to chipper.

Thing is you don't need to be a mathmaical genius to hold a 3/4 board in your hand and know that after 5 cuts the kerf difference between circle and band would have turned it into a full board, or hold a 1/2 piece in your hand and know it could have made paneling.
2 flitches like that to the log, average 7 boards per flitch. So 14 boards recovered where there could have been 16, or about 13%.

Recover 100 ton and it could have been 113 ton. At $1600 per ton roughsawn KD ex mill thats $20k sent to the chipper which for me is borderline viable given band costs and equipment prices because I'd need a serious band resaw and they aren't cheap.

If I double my output in those species bands become quite profitable. And when we're in the high value rainforest species that sell at double that my sawdust pile starts to look real expensive.

I'm convinced that for me at least adding a band resaw is a smart move. No way I'd ever use anything but circle headsaws though.
The quickest way to make a million dollars with a sawmill is to start with two million.

quilbilly

When i was milling on an Lt 70 we usually only got a few touch ups before the band broke at the weld. I must say we were pushing for production though and weren't slow once we hit a spot where we could push it. I've also though a twin blade like an MD or mighty mite mahoe etc followed by a band resaw or sash gang would really be best. If you were stationary that is. I think logosol makes a mobile sash gang though.
a man is strongest on his knees

Ron Wenrich

I've always taken time to be a factor.  Time is a non-renewable resource.  If recovery means that you have to take more time to get the extra board, then it probably won't pay off unless in high value wood. 
Never under estimate the power of stupid people in large groups.

ladylake


Longtime Lurker

(I think scale of operation is a big factor)

You hit the nail on the head, I run my bandmill by myself when sawing at home and it keeps me plenty busy, with a circle mill you need 3 to 5 employees to get the most out of it.  Steve
Timberking B20  18000  hours +  Case75xt grapple + forks+8" snow bucket + dirt bucket   770 Oliver   Lots(too many) of chainsaws, Like the Echo saws and the Stihl and Husky     W5  Case loader   1  trailers  Wright sharpener     Suffolk  setter Volvo MCT125c skid loader

killamplanes

Operational size is a real biggy. And value of logs. My pea size brain, in a perfect world would go with circle for break down of log. Slabbing down with a circle mill, then resaw thru a band. If you went around here and looked at the sawdust pile from the primary circle mill. Then went to the gang saw shed and looked at the sawdust pile it is absolutely huge. Expecially if you were making 5/8 thick pallet boards or something.  But there again if your buying logs for a quarter a bdft. The sawdust pile doesn't hurt to bad, at a 1.50 a ft I would be a nervous wreck ;D
jd440 skidder, western star w/grapple,tk B-20 hyd, electric, stihl660,and 2X661. and other support Equipment, pallet manufacturing line

longtime lurker

Right at the moment this entire kerf issue is rolling around my head a lot, mostly because I have to expand capacity in the near future... Say 12 months. My circle resaw is just about wore out, and either needs replacement or a major refit.

I don't see time as an issue much, mainly because regardless of whether its a linebar circle resaw, linebar band resaw, circle gang, sash gang, horizontal band either single or multi head: someone s got to stand there and drive it. So it really comes down to pick your evil.

Gangs make a lot of sense in terms of output per man hour. Sash or circle you feed it wood and it spits out boards in a very efficient manner. Sash gangs in particular interest me because you get extremely accurate cuts combined with band resaw recovery rates, but without the big band operating costs..  Sharpen and set them  but no need to hammer.
The issue I see with gangs or multihead resaws is grade: you decide today were running 4/4 and that's what you get, there's no option to look at the cut face and change thickness to a different use that suits a grade rule better or shim cut to remove a defect.

Circle resaw like we currently use the issue is kerf. Against which its the devil I know which is always a good thing.

Band resaw the issue is band costs. I'm not big enough to justify the filing room, and sending out big bands is going to take a lot off the profit the extra recovery might make.

Thing being that this decision I've got to make really is going to be a make me or break me one. I could play it safe and stay with circles, but my gut tells me that might not be the best bet because doing the same old thing can only give me the same old results ( albeit with less downtime for repairs) and those results are exactly the same as my competition gets also.

Brewco do a 2" band headrig. I look at the tube videos and wonder  how it would work as a linebar resaw. Band kerf, option to change sizes on the fly, bands we could handle in house without a hundred thousand tied up in a filing room. I'd like to find out more about that.
.
Kinda wandering off topic here but we haven't got to food yet :D
The quickest way to make a million dollars with a sawmill is to start with two million.

Darrel

I worked in the big soft wood mills on the west coast for 21 years (1971-1992) and never heard of or saw a circle resaw. This leads me to believe there must be something that makes a band resaw more affordable. And the more I think about it, the more I think it must be due to the fact that these big mills already have a whole wack of bucks invested in a filing room so sharpening costs of band vs circle are negligible. At that time most of the big mills ran twin band vertical resaws that were very easily adjusted for size on the fly.

But things are different now and the compitition is greater.
1992 LT40HD

If I don't pick myself up by my own bootstraps, nobody else will.

Ron Wenrich

When you get to bigger operations, bands do make sense.  But, you're talking on a scale of band much bigger than what is found on the smaller band mills.  Production bands are usually 1/8" where these smaller bands are 1/16".  You're using much bigger wheels and a lot more input hp. 

Hardwoods are much different than softwoods.  Logs aren't as straight, fiber is harder, and grain isn't always as nice as what a softwood log has.  Even the guys running big band resaws often have a circle mill as their breakdown.  You have to remember that most hardwood mills saw for grade, not necessarily yield. 

You're right about the filing room setup.  Once you have that, then you can go with all bands.  But, a small mill can't afford the investment of a filing room and training of a millwright.  So they either go with the technology that they know in circle saws, or they go to the thinner kerf disposable saws.   

Thin kerf saws don't take as much maintenance as a big band, and their lifespan is a lot less.  Bands can be sent out to be sharpened or they can sharpened on site with a filing room that costs much less. 
Never under estimate the power of stupid people in large groups.

bandmiller2

If your a careful sawyer ( most owner/operators are) a headsaw can outlive you. I have a Simonds built in 1948 still good and the old Diston I have on the mill now is pre war, probably both wars. Everyone harps on kerf but circular production far outstrips the loss. What it boils down to is circular mills are a minor industry with heavy machinery wile bandmills are usually a backyard part time venture cheaper to buy, handle and move. Frank C.
A man armed with common sense is packing a big piece

longtime lurker

One thing I have noticed over the time I've spent here or trolling the internet is that I've never seen anything like the high output circle resaws that would be normal in an Australian hardwood mill in the US. Never understood why either... Its a real quick way to double or triple the output of a linebar carriage mill.

My old doll is an older version of this, by about 30 years and quarter million ton of flitches.

https://youtu.be/f3A1EomMCOQ

The quickest way to make a million dollars with a sawmill is to start with two million.

Ron Wenrich

There are resaws made in the US that are circular.  Some are linebar, some are gang saw, some are slab recovery saws.  Pendu makes only resaw equipment, and its all circular.

The big thing is how much the equipment costs, and the capacity that these machines have.  Pendu makes a gang rip that is uses thin kerf circular saws.  They are used mainly with pallet producers in our area.  They have a high capacity and are easy to work on.  Most mills do not produce pallet stock.  They produce pallet cants, and the pallet maker makes the stock.  Much more capital efficient.  In addition, these resaws can be fitted with moulder heads that can produce cabin stock with many different styles. 

They also make a circle scragg mill, and have a slab recovery saw that makes bunches of boards out of slabs.  Again, it is geared mainly for the pallet industry. 

Hardwoods in my area go for grade and ties, with the least desirable market being pallet stock.  A high end mill with a linebar resaw is normally a band operation.  Some use big bands, some use the smaller bands.  It all depends on the size of material you want to send through.  Circle resaws have a limited capacity compared to a band resaw.  I imagine that you could put a large circle saw instead of a band saw, but I don't know if you'll get the same feed rates. 

https://www.youtube.com/watch?v=5ipcmIpkgBA


Companies like Brewco make a resaw that gets good production for smaller operations, without breaking the bank.

https://www.youtube.com/watch?v=sZlQ6XScJEQ
Never under estimate the power of stupid people in large groups.

Darrel

Wood-Mizer has entered the high output industrial sawmill equipment market and is introducing a new to them line of wide band head rigs and resaws that can be quickly adjusted on the fly. I know that my operation will never need this so I'll continue to use the somewhat higher cost disposable narrow bands. They also are providing bigger and faster edgers and gang saw's that use circle saws. They are calling the new line Titan.

Anyway, I thought for those interested, it might be worth a look.

https://forestryforum.com/board/index.php/topic,94695.0.html
1992 LT40HD

If I don't pick myself up by my own bootstraps, nobody else will.

longtime lurker

Learn something new every day: If I thought Circle gang or scragg, Pendu would come to mind but I didn't realize they did bench style resaws as well.

The Brewco and other horizontal band resaws leave me a bit confused to be honest. How can you cut grade if you can't see the bottom face which is where the board is being removed from?

I think it's about how our timber leaves the headsaw. You guys tend to aim for a "square log" which is then passed around the resaw taking off a slice at a time. Here, if we're chasing say 6" boards, we flitch at 6" on the headsaw using the linebar, then pass that to the resaw, so the resaw is just removing boards by width a lot of the time. Given that hardwood framing is still big here my thought process on the resaw becomes " which application will this 6" board suit?"  And thickness to cut at... 4/4 for flooring, 3/4 for paneling, 8 or 12/4 for framing... is determined by what I can see on the face I'm removing boards off. Being able to see the face allows me to direct each board to the highest value or most saleable application on its merits.

I think your logs are more consistent too... euc tends to be variable grade through the log so we get good clean boards suit higher value application out towards the sap, structural grade lumber in the middle, and by the time you get to the pith area you're down to landscape or pallet material. Makes it hard to specialize a sawmill, the log resource dictates that you dabble in them all.
The quickest way to make a million dollars with a sawmill is to start with two million.

Ron Wenrich

Our hardwoods grow the same way.  We have clean boards on the outside and defect develops as you cut closer to the heart.  In addition, our grade is dependent on the backside of the board.  If you cut into defect, a clear faced board can drop to low grade.  There are some markets for the clear faced low grade, but not many.  So, there is a good deal of skill placed on reading a log.  Like most things, the skill is knowing when to stop cutting on a face and turning.

As for sawing on the bottom, you know which side to saw by looking at turning the cant.  It makes no difference if it cuts from the bottom, top or sides.  Since you're making a single pass, that needs to be looked at if you're sawing for grade recovery.

Most times a mill will be set up for a single thickness on a species run.  It makes inside out sawing much easier.  But, there are times when multiple thicknesses work.  I used to saw tulip poplar with 4/4. 8/4, 10/4, and 12/4 specs.  The lower grades went to 4/4.  Sometimes we sawed oak with a 4/4 and 8/4 spec.  These also had the lower grades in 4/4.  We had a single headrig.

This can be done on a resaw.  When you run into low grade, you turn.  Eventually you'll have pallet stock.  Some mills have markets for pallet stock that is 4" or 6" by random width.  Works well for not accumulating low grade in lumber and easy on the resaw operator.  Ideally, these could be passed through a gang saw at the mills and further grade can be gotten. 

We do have edgers that are called bull edgers.  They have a typical edger on one side for edging boards, and a gang saw on the other.  Expensive, big, and takes a lot of power.
Never under estimate the power of stupid people in large groups.

longtime lurker

Our grade rules are weird.
The hardwood Structural grade rules here are a thing of beauty. It's simple, easily applied, and for someone such as yourself I'd think you'd be confident enough after a day of training to sit the exam and get your own stamp. It was written to be understood and applied by  Sawmillers and it's a common sense system.

Our " structural appearance" rule is dumb. Structural appearance rules apply to things like flooring because how houses are traditionally built here the flooring is a structural component, so it's got to carry both structural rating and then gets broken into three categories based on appearance: Select, which has very little grain variation minimal tight knots, tiny veins etc but the overriding thing is uniformity through the package. Rift to quartersawn with straight grain is the norm.
Standard and Better is a bit more generous about knots, gumveins, the odd borer hole and allows for a range of grain patterns through the package. Backsawn material with the characteristic swirling grain is typical S&B. It's the ost common grade because of the backsawn grain thing.
Feature grade is everything else... big knots, holes, and highly figured grain patterns.
Cabinet and joinery type applications use a different rule as non structural uses of lumber.

I avoid S&B in most of my species: I can't compete with the big guys there on cost of production so I don't even try. I chase the premium that comes with select grade where they can't compete with me. But part of any quarter cut pattern is you always get a % of real pretty boards.



 

So in that picture there the valuable stuff as flooring is the straight grained stuff. The pretty ones because of the grain go feature grade which is the least valuable flooring material.

So normally instead of cutting those at 7/8 for eventual 3/4 Tongue and groove I'll change to 1 1/8 for cabinet and joinery use where it becomes the most sought after material, or run it at 3/4for paneling where feature grade is in demand.

Can get complex here stacking lumber... I'll have 4/5/6 inch widths coming off in three different appearance grades in 2 thicknesses for flooring / paneling etc, plus structural framing sizes, plus the figured stuff for cabinet& joinery markets...all out the one log. Species change day is a nightmare . But by cutting each log on it's merits in terms of maximizing value in saleable sizes it means we're actually a quite profitable business.

As with any grade rule the trick is in knowing it and your markets that well you can use it to your advantage instead of having it use you. But it also means a look at the face before you cut to get it right for application.

I ran a big mill once... I think there were times the setworks would be just about frozen up at the inch mark from running flooring and decking stock for weeks. I am really enjoying being little enough to do it this way instead.
The quickest way to make a million dollars with a sawmill is to start with two million.

Thank You Sponsors!