While I do have some experience on bandsaw portable mills (growing all the time) , I am always learning and there are folks on here that have thousands of hours working with them.
I got some blades from a manufacturer. When I got them I did not really do a close inspection of them but put them on the mill and started to use them.
I tend to use blades, stockpile them when I pull them off and then set and sharpen at a later date.
After several blade issues I started to look at the blades more carefully and noticed that there was an anomaly at the weld where there was a very small tooth remnant.
(https://forestryforum.com/gallery/albums/userpics/34143/20170212_073243r.jpg?easyrotate_cache=1486921034)
I questioned how that would effect sharpening since for the remnant to be present the tooth, spacing at the weld had to be different from the rest of the blade. That would make the sharpening process "interesting" as the blade came around and the weld passed through the sharpener. These are 7/8 spacing teeth (0.875). The normal tooth mics out at 0.875 (7/8th) but at the weld the tooth spacing is only 0.084. Not a tremendous difference but a little over 1/32nd of an inch. The gullet grind will remove the mini tooth but the next tooth will take a moderately significant grind and be smaller as a result.
At least I think that is how it will go.
That is not the real issue; at least not initially.
I previously took the following photo to show the mini-tooth but never looked at it until now. I wish I had. I obviously did not inspect the weld area as I was only interested in documenting the mini-tooth with a photo. I should have been more detailed visually.
(https://forestryforum.com/gallery/albums/userpics/34143/20170127_133350r.jpg?easyrotate_cache=1486921015)
Having now had 3 blades break at the weld before they ever got to the sharpener for the first time; I am rethinking what I should do next.
Should I put them through the sharpener before I ever put them on the mill or should I do a hand grind of the mini tooth to remove it as it appears to be causing stress fractures in the blade.
I have not done an inventory of the remaining new blades to see if everyone of them has the same mini-tooth. I need to do that. I have gone back and the only blade that made it to "dull" has the same mini tooth as well as the ones that broke in the weld.
Looking at the second picture it looks like they did not weld all
the crack...
I would not call that a tooth . It looks like the runout from the weld process . If they make the bands to length most likely the teeth are already sharp so they just cut and weld . Looks to me like a crap weld job .
Agree on the crap weld job. That's excess weld and I would think it is why it cracked there.
Totally unsatisfactory. I would contact the blade manufacturer with the pictures.
Won't say who from but I had a bunch with half a tooth sticking up from the weld I don't buy from them any more.
I have seen that on several bands I have used of different brands.
It will screw up a few teeth when sharpening because the indexer hangs up on it. The way to take care of this is to let it sharpen that tooth/gullet first and that takes care of the excess weld and it isnt an issue after that.
However you shouldnt be breaking them. There must be a problem either on their end or yours. The looks of the weld in the second picture is not 100%. If they are breaking at the weld then it is your supplier that needs talked to. A good reputable company will want to make it right. Contact them.
PC
@pine These are the blades
(https://forestryforum.com/gallery/albums/userpics/33477/DSCN1031.JPG?easyrotate_cache=1486929101)
(https://forestryforum.com/gallery/albums/userpics/33477/DSCN1031.JPG?easyrotate_cache=1486929101)
(https://forestryforum.com/gallery/albums/userpics/33477/DSCN1033.JPG?easyrotate_cache=1486929255)
Fresh out of the box the cut like a charm but the grinder I got from Woodland don't like these blade's it mighst do 6 or 7 blade's fine then not touch 2 or 3 then take half a tooth off
I've heard of double hard but I think you got double cut....
Quote from: goose63 on February 12, 2017, 03:05:10 PM
@pine These are the blades
<pictures snip>
Fresh out of the box the cut like a charm but the grinder I got from Woodland don't like these blade's it mighst do 6 or 7 blade's fine then not touch 2 or 3 then take half a tooth off
Thanks @goose63
I appreciate it.
Wow that makes my blade issue seem like nothing.
have no idea how those could be sharpened with even the best sharpener.
Looks like somebody made a bad weld, then cut out the weld and re-welded. Any sharpener definitely gonna have problems with that. I have seen blades where a short section had been spliced in, but never anything like this.
Quote from: scully on February 12, 2017, 12:48:10 PM
I would not call that a tooth . It looks like the runout from the weld process . If they make the bands to length most likely the teeth are already sharp so they just cut and weld . Looks to me like a crap weld job .
Quote from: LeeB on February 12, 2017, 01:20:34 PM
Agree on the crap weld job. That's excess weld and I would think it is why it cracked there.
I guess I did not accurate define my term "remnant mini-tooth" as obviously with their location it can't be part of an actual tooth (it just juts up like a mini-tooth).
Now Goose63's pictures clearly have extra mini teeth.
Even if the blade steel roll was cut exactly wrong; injecting another real tooth closer than 7/8" to
both of the other "band weld teeth" would be hard to have a spacing shorter than 7/8" It would be slightly longer. I think the weld analysis is probable the correct analysis. It is consistent blade after blade. It is obvious the side of the blade was polished post weld just not the gullet.
Sharpening is still an issue as the spacing is wrong at the weld.
I also think the nub creates a stress in the cut that originates a stress crack. Do you folks think grinding/filing off the nub will alleviate the problem?
Me, I'd have a talk with the manufacturer. Then I'd call the blades junk and buy elsewhere.
When you get tired of messing with those blades, contact FF member Cutting Edge. He's an authorized distributor for Kasco blades (a FF sponsor). If you give him some notice he can usually "bundle" your order with others and offer you free shipping.