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What to do when coarsest bandsaw teeth are too fine? (12" dia solid round)

even more reason not to fuck-up what he has :) . i'd consider sending him some 1" x 10p band stock if he'll pay the shipping.

Wouldn't break the bank to prepay shipping, would it?

He's working under the umbrella of a charitable organization based in the USA that handles transport logistics. See his request in a thread on PM for drills.

A "direct" ship into a country in dire economic straits has a better than even chance of vanishing at the border.

BTDTGTTS. Italy, even, as-of-the 1970's.

NINE "fewer" known-entities to grease or guard against in shipping a whole danged satellite Earth station by AIR - just to avoid near-certain loss of its major bits if shipped by SEA.

Europe has improved, but experienced brokers still must "just deal with" this sort of environment, all-too-much of the rest of the world.
 
"heavier machine"

nope. no-one said anything of the sort.

the solution is to use a band suited to his machine . 10 , maybe 8 tpi max on
heavy steel.

in the same way i wouldn't attempt to cut a slot with a 2" endmill on an R8
bridgeport... or cross the atlantic ocean in a fish/n/ski boat....

not critical, but practical machining.

if he runs those wood-pitch-bands , he'll soon fuck-up his saw. then we'll
no-longer have a discussion.. :)
 
"Wouldn't break the bank to prepay shipping, would it?"

it would for me.

i'm supporting parents and family w/ medical issues,

so... perhaps you'll chime in w/ your support?
i've offered materials...

i'll bet there's a paypal address..........................
 
looked it up for fedex post... you don't want to know . 3x the value of 100'
of coil.

nevertheless, he asked us a specific question about TPI.....NOT to send Bob
fucking Geldoff for a usa-for bandsaw relief fund tour. he still needs the proper band for his work.

said he couldn't buy a coarser blade- i say didn't need one in the first place.
wrong direction....

i'll bet he could buy a finer one.
 
3x the value of 100'
of coil.
And there is the key barrier to getting ahead in his whole environment.

Logistics. Cost of transport. That part was only to his "depot", not all the way to Africa, yah?

He's able to "connect" - they have internet linkage or we'd not be seeing his posts.
That lets him ask for - and get - good advice.

He just doesn't have the means to put very much of even the best of advice into actual practice. There is a void under that internet link. The country never did have a pervasive industrial base. Can't even raid scrapyards for things that were never there to BE scrapped.

His choices WILL be sub-optimal.

Not out of defiance. Simple resource limitations.
 
The cut is chattering like crazy now that I'm down into the widest part of the profile. I'm using a 4tpi Lenox Classic bimetal blade. The chips are coming out trapezoidal like the Lenox instructions show indicate gullets getting filled up and skating through the last part of the cut. The normal remedy is to use bigger teeth for more gullet capacity. Problem is, they don't make any coarser in 3/4" blades.

.............problem is that they make the band for the saw and it is not
being used .
 
The cut is chattering like crazy now that I'm down into the widest part of the profile. I'm using a 4tpi Lenox Classic bimetal blade. The chips are coming out trapezoidal like the Lenox instructions show indicate gullets getting filled up and skating through the last part of the cut. The normal remedy is to use bigger teeth for more gullet capacity. Problem is, they don't make any coarser in 3/4" blades.

.............problem is that they make the band for the saw and it is not
being used .

"Problem is.." you are mis-cast.

You should be our "negotiator" with Iran or North Korea, where a hard head actually IS as useful as recognition of the local realities.

:)
 
Just FYI, I used to cut 10" rounds with 2/3 pitch Lennox QXP variable pitch bi metal blades in my Amada HA250. Only issue was clearing the chips out of the bin fast enough.

A real saw is definitely the answer.
 
Just FYI, I used to cut 10" rounds with 2/3 pitch Lennox QXP variable pitch bi metal blades in my Amada HA250. Only issue was clearing the chips out of the bin fast enough.
Some kind of "real saw", if Jason's wishes were fishes.

I do have comparable-performing blades I could donate, but they are not round-and-round versions. Back-and-forth, rather. I'm not a "business", prefer quicker blade change over saw throughput and blade-welding nuisance.

Lenox Hackmaster-V, 3//4 pitch Varitooth, 450 mm X 45 mm and 2.2 mm thick. The old Kasto is a Metric-denominated close match to 12" X 10" at a go, stock rotation works...but .... he doesn't have one of those or a workalike, either.
 
We use 5-1/5 - 8 varipitch X 3/4 blade for Everything. .049 wall tubing to 12"X1" flat 1018 barstock. Don't know the HP but it's a 30+ YO Rockwell saw. I tried 1" blades and coarser pitch blades, went back every time to the 5.5 - 8 Lennox. We do have flood coolant and I'm sure that helps, but we cut up to 9" round stock all day in aluminum and steel and it works fine. Lay flat bar down 12" wide and it's still fine. Coarser pitch just made problems and jammed and broke. Can't explain why, but it works and I've had others say the same.
 
Thanks all for your contributions. I don't want to get defensive about my equipment, and I certainly do have to work with what I've got - and admittedly I've never spent time around a high-HP "real" h.bandsaw. However, with all of that said, my practical experience and the theory as I understand it don't indicate that this profile is unsawable on my current machine. (Though I certainly admit there's room for improvement in the sawing cycle time, that's not a big consideration in my situation.) Please show me where I'm misunderstanding.

First, I've done a considerable amount of sawing in 6" solid rounds on this saw with that same bimetal 4tpi blade configuration, and usually with much heavier feed pressure than I'm using for this instance. It works great. No sign of bogging the motor down. So, unless I'm misunderstanding something fundamental about sawing, it seems like given the same material/blade/tension, increasing the LOC would only increase the HP required linearly, not exponentially. If that's true, and I'm not stressing the motor in a 6" LOC, I should only need 2x that HP to make a 12" LOC - correct?

Second, the suggestion that I drop to a finer toothed blade and reduce feed pressure to compensate doesn't make sense to me. I'm already at the saw's minimum feed pressure (short of standing there and holding the head up with my hand through the whole cut.) So given that I'm already filling big gullets with the least feed pressure possible, how does decreasing the gullet size by going to a finer pitch while being unable to decrease the feed pressure do anything but make the "gullets are full" problem worse?

The HP doesn't seem like the chatter culprit to me, not when Lenox's own guide is indicating my trapezoidal swarf is a sign of overloaded gullets. I can see the logic, however, of the argument that my saw is inherently not rigid enough to handle the cutting forces required for 12" of this cut. My only thought on that though, is that since I'm still not sawing at a force greater than the saw's motor (which we can know, I think, since it's not bogging down), why would Wells design a saw frame that can't take as much cutting force as the motor they put on the saw?

I'm not trying to be argumentative, and I know the forum has collective millennia more sawing experience than I do. My gut, however, is that if, from the beginning, I had employed the "rotate 45 degrees" technique to keep the max LOC down around 6-8", aside from being a little labor intensive and certainly slower than a "real" big saw, I would've done just fine, despite my saw's limitations. If that's true, then perhaps ignorance is bliss - never having been around a bigger, badder saw, I don't know what I'm missing out on. :)

I wasn't able to get over to have the blades rebrazed the other day. I'll report back when I do. (Un)fortunately I have a need to cut a second slug off of this same material, so doing that slug from the beginning with the 45 degree plan will let me know, start to finish, how and how long the process went. Once I've got that, you can all tell me how your bigger, tougher saws could've done the same thing in a tenth of the time. :)

----

As an aside for anyone curious, what I can find locally related to sawing is the following: 12" hacksaw blades and angle grinder wheels. For machining, nothing. Fab is a little easier, we can get limited steel, 6013/4043/308L/Ni rods, scratch brushes, and recently CO2. Past that, everything I have here, I've brought with me from the States. We generally get to put stuff into someone else's shipping container once every 12 to 18 months. Those are my supplies. We have people fly over a couple of times a year to visit, and they're usually willing to bring smaller stuff in their luggage, but for heavier consumables or equipment, I have to wait for those shipping containers. When I flew over in December, one of my bags had 12 unwelded (cause they fold better) 8/12tpi bandsaw blades. That kind of resupply is just how we have to operate. :) We find stock at the scrap yards periodically, but certainly not old machine tools. You'd be amazed what clapped out machines are worth over here because of the headache of the alternative, bringing them in, because of customs (or at least I was, being from MI, where we can get used machines pretty reasonably most of the time.)

It's tiring having to guess at what supplies you'll need that far in advance - but it's also kind of fun - a little like the TV show Junkyard Wars/Scrapheap Challenge. Do what you can with what you have and can find!

Thanks again for the input, everyone!
 
I should only need 2x that HP to make a 12" LOC - correct?
No, it isn't. You have had the "real answer" all along - from Lenox.

The geometry of the gullet and spacing of the teeth do not have enough volume to hold the amount of material removed in a cut that long. Fewer teeth "usually" mean larger gullet area per-each, but not always.

Larger gullets exist where tooth-count is not so coarse as well. You see them on 2-man and bow saws for cutting wood.

For the blades you actually HAVE - good ones, BTW - even which motor is powering it or which frame is holding it is not the issue. X amount of material is being removed in the pass, gullets can only hold X-minus-something.

You can only prevent gullet overfill by reducing the "bite" depth. Or its run-length. Or both

Turning the stock reduces the run length. Lowering the force that "advances" the blade reduces the depth.

No need to stand there and hold the saw up, BTW. Rig an adjustable counterweight for use on these "special" cutting needs.

As to why saw openings are large?

Most general-purpose saws see solid round or solid-any-other shape only once in a while.

Cutting an Ell, hollow rectangle, pipe, tubing, or an I-beam is common. And less demanding of gullet space.

And "Oh, By the way". Super saw, big C.O. Jones? Mostly those are for shops that have to do sawing all day or even on multiple shifts, to high accuracy and repeatability so as to reduce cost of other operations. A necessity, not bragging-rights, IOW.

I'd not be able to justify my Kasto, save that someone tumbled it off a loading dock, and I knew how to patch up the busted-off bits when it went for scrap price.

:)
 
Second, the suggestion that I drop to a finer toothed blade and reduce feed pressure to compensate doesn't make sense to me. I'm already at the saw's minimum feed pressure (short of standing there and holding the head up with my hand through the whole cut.) So given that I'm already filling big gullets with the least feed pressure possible, how does decreasing the gullet size by going to a finer pitch while being unable to decrease the feed pressure do anything but make the "gullets are full" problem worse?

I'm not sure what the solution is.
But having more teeth in the cut would reduce the pressure per tooth. Also more points of contact may help stabilize the cut and prevent chatter.

Just my thoughts.
 
No, it isn't. You have had the "real answer" all along - from Lenox.

The geometry of the gullet and spacing of the teeth do not have enough volume to hold the amount of material removed in a cut that long. Fewer teeth "usually" mean larger gullet area per-each, but not always.

I may have been trying to respond to too many different things in one post. I completely agree that full gullets aren't remedied by HP. I was addressing that comment to the "your saw it so weak to be able to cut that stock" comments. I agree that the gullet capacity issues are my current problem, and think the partial rotation plan is the one to beat.
 
It's easy for us to tell him the solution is a heavier machine but he's trying to get by with what he's got. Been there, done that.
"Been there, done that." PM has some of that trait, and another; in a large population with incalculable varied resources for the participants. One portion just hit the toolroom, thinking it's common. Another eats brown bag weeks at a time.
You can sort of tell, when the "haves" are actually employees of long running shops; with tooling no farther away than a memo to the buyer.
 
I was in Nepal about 3 years ago. They were doing some rebuilding after an earthquake. Lots of concrete with #4 or #5 rebar.
At the mill they would fold in half bundles of 40' bar so they could transport them. Then you'd see 3 guys carrying the bundle around the site.
One day we saw 2 guys squatting down trying to cut a piece. One guy at each end of a hacksaw with an old blade, taking ages to make a cut. It blew me away that they didn't have one of those simple shears.
Just goes to show that in many parts of the world you make use of what you've got.
Bob
 
I'm trying to saw slugs off of a 1' piece of 12" dia solid round. I routinely saw blanks off of 6-8" solid rounds, but this is the biggest I've ever attempted on my workhorse Wells 8m (which I realize can't take a 12" bite, I'll have to saw most of the way from one side, flip, and connect.)

The cut is chattering like crazy now that I'm down into the widest part of the profile. I'm using a 4tpi Lenox Classic bimetal blade. The chips are coming out trapezoidal like the Lenox instructions show indicate gullets getting filled up and skating through the last part of the cut. The normal remedy is to use bigger teeth for more gullet capacity. Problem is, they don't make any coarser in 3/4" blades.

Several brazed blades have broken at the braze, I'm sure because of the excessive vibration (this was after the first blade stripped a tooth, which then stripped all of the rest of the teeth on the blade before my assistant shut it off - I've since moved to start a different cut, not wanting a new blade to find any of those old teeth.)

Any advice?

I'm trying to saw slugs off of a 1' piece of 12" dia solid round. I routinely saw blanks off of 6-8" solid rounds, but this is the biggest I've ever attempted on my workhorse Wells 8m (which I realize can't take a 12" bite, I'll have to saw most of the way from one side, flip, and connect.)

The cut is chattering like crazy now that I'm down into the widest part of the profile. I'm using a 4tpi Lenox Classic bimetal blade. The chips are coming out trapezoidal like the Lenox instructions show indicate gullets getting filled up and skating through the last part of the cut. The normal remedy is to use bigger teeth for more gullet capacity. Problem is, they don't make any coarser in 3/4" blades.

Several brazed blades have broken at the braze, I'm sure because of the excessive vibration (this was after the first blade stripped a tooth, which then stripped all of the rest of the teeth on the blade before my assistant shut it off - I've since moved to start a different cut, not wanting a new blade to find any of those old teeth.)

Any advice?
MUCH ADO ABOUT NOTHING
Our toolroom atendandant also saws all of our stock. He uses the same blade all day long. You only have 10 cuts max. Just rotate each cut 3or 4 times. Our guy would cut 10 inch STAINLESS with an 8 tooth blade. Edwin Dirnbeck
 








 
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