Morning
Breaking blades constantly
I will try to keep this to the point.
I've run my lt40 wide for a year and a half with very few issues. I've always had Woodmizer sharpen my blades for years. I'm out of town and cutting all the lumber for my brothers house. I had a local guy sharpen my blades so we could get them back quicker. I've broke 7 out of 10 blades in 2 light days of cutting. I've broke maybe 3 blades since I've had the mill. I was cutting oak and after breaking 6 I switched to pine. Broke a blade in no time. Can't keep pitch off of them too. I've tried every solution I can think of other than diesel. But I've never needed anything but pinesol in 8 years of sawing. Did my blades get wrecked????????
I'm in a jam and only brought 25 blades. Any help would be appreciated.
Thanks in advance
I would look at blades first if nothing else has changed. You might look close at the gullet and see if the full profile was ground vs just hitting the tips of the teeth. Also lack of proper set could be causing issues as well.
I notice a heavy burr in the gullet. I've truthfully never checked my others because I've never had an issue. So I'd say he sharpened more than the tip. Will a burr cause a bunch of issues. I guess I should know all of this by now but been blessed to be problem free all these years in this aspect.
I'd invest in a box of new blades to finish your task and know that the local sharpening wasn't up to snuff.
Is it just one burr at the weld? If so, it sounds like a leftover from the welding process. That disappears on the first sharpening so that suggests the gullet was not sharpened.
Do the resharpened blades cut like you're used to with a freshly sharpened blade?
A close look at the blades with a magnifying glass should help you see if there are cracks in the gullet on your blades. When I've broken blades most times it is due to stress cracks in the gullet. A close look at the break on a freshly broken blade will also reveal if there was a crack in the gullet. When I get a blade break, I expect others of the same age/batch to break as well.
Other times blades have broken at the weld. Breaks at the weld are not rare but much less frequent and can be replaced by WM.
Without seeing the bands we are all guessing and before we throw the guy who sharpened them under the bus...what condition are your wheel belts in? If the band is hitting the wheel due to worn out belts, or riding against the roller guide shoulder then you will break bands quickly.
Just check the potential obvious places too.
If you are building a lot of pitch is the blade tension increasing from build up under the belts? try some diesel to keep the blades clean.
?
Quote from: Southside on January 03, 2021, 02:31:10 PM
Without seeing the bands we are all guessing and before we throw the guy who sharpened them under the bus...what condition are your wheel belts in? If the band is hitting the wheel due to worn out belts, or riding against the roller guide shoulder then you will break bands quickly.
Just check the potential obvious places too.
When I called Woodmizer Maine with a blade problem, the first thing he asked was the condition of the tire belts. He also said to check the condition of the drive belts. A slipping drive belt will slow down the speed of the blade.
Thanks for all the help. The burr is heavy on every gullet. On one side and that's the side I'm getting pitch build up.
Belts are new or have 10 hours on them. This was the first sharpening on these and usually I don't push my blades hard. I try to pull them long before they are dull. I'm going to see how quickly I can get new blades. Just didn't know if I was missing something obvious. And I'm not throwing the gentleman under the bus.
Thanks
Looks at your guides and see if it looks like the blade is riding on them. If so, heats up blades and will cause breakage too.
Pitch buildup causes
all sorts of evil.
- Be sure that the lube is going on the teeth area of the blade, and not just the back of blade.
- Add Pinesol to tank along with dish soap...LOTS of it. I discovered I was being stingy with the soap and adding LOTS really help. I put about 1/2 a small retail bottle in per tank.
- As others mentioned (or will). Diesel helps. I use the soap/sol combo and use a squirt bottle to hit the blade a bit if buildup starts gaining on me. If I sawed pine more often, I'd put a little aux tank/sprayer on with diesel.
Just a question here. Does the guy who sharpened your bands have the proper cam, CBN wheel, or whatever he needs to sharpen your profile blades? If not, that would possibly cause issues.
Hard to imagine that something in a sharpening process contributes to blade breakage and residue buildup. Maybe if it wasnt sharpened well at all and continued use was like pushing a dull band. But you would have noticed if the blades didn't saw like they had been sharpened (?).
Buildup on the burr side seems like a coincidence. The burr side would be the inside of the blade on my sharpener. The inside of the blade is where most buildup occurs (between band and band wheel). And isnt the burr gone after sawing one board?
Don't have an answer as to what it is though.
7/10 breaking is not normal at all. I've had 3 or 4 bands break in the 6 years I've been milling. I only use WM resharp. But from what you guys are describing, seems like a burr in the gullet could catch sawdust/buildup.
Is this a mill that has a tension dial gauge? Have someone watch it as you're sawing and see what happens? Does it change?
That burr is normal after sharpening. I rub it off with a piece of hardwood before setting to make the set more accurate.
There are burrs and then there are what was this guy thinking type of burrs. All grinding on steel will leave a burr (18 years and counting experience grinding metals), but heavy and dry hogging will leave a burr that can only be removed by further grinding as well as causing a hard spot along the contact patch between the grinding wheel and band.
Do you have a picture of the burr and a side by side comparison of a new band and a suspect band?