Broken tooth

[LCHIEN]

Miter saw been splintering and making rough cuts whereas it used to give polished cross cuts with the Diablo D12100X 12" ATB miter saw blade.

On inspection found a broken tooth The other teeth look and feel OK but this one is rough around the edges. Almost directly opposite the broken tooth (49, but not 50 teeth away) is a slightly bent tooth. My dial indicator says its .009" bent to the side.



Have the tooth replaced? Resharpened? $29 for sharpening not sure how much for the tooth. Two years old

New $75 at HD, $58 at Amazon.

What's the advice here?

Maybe I did this when cutting some Aluminum. Should have put on the cheapo blade that came with the saw. HiATB blades are fragile at the tips. Was too lazy for one cut. From now on just TCG non-ferrous metal cutting blades for aluminum!.

[LCHIEN]

So anyway after doing something bad to this blade I have a sharp blade, cuts almost like new but with a teensy bit of tearout at the back on my miter saw. I ended up spending nothing but a fair amount of time measuring, complaining then working on it my self over four weeks.



I do have a new blade I bought when this first went south so I basically have a spare for that cost.

[LCHIEN]

How I ended up with this blade

https://www.sawdustzone.org/forum/discussions/tool-talk/846100-miter-saw-tearout

[capncarl]

I don’t know about tooth replacement. I have a couple of 3/4” carbide tipped 111” blades for my Rikon bandsaw. I hit a loose knot while resawing a large piece of old sinker pine and the proverbial hitting the fan happened, bending the blade and knocking off several carbide teeth. I sent it back to have the teeth replaced and blade re-straightened. If the replacement of carbide bits are an example of what a repaired blade looks like then I’d say you would be better off trying to grind that bad tooth off and continuing using the blade.

[LCHIEN]

Talked to the foreman at the local sharpening company.

He said that replacing a tooth would cost about $25. he recommended that they would just grind down the old tooth so it didn't stick out and that you'd never notice being just a 99T blade instead of 100.

I also said one tooth looked bent, he said they would straighten the tooth and grind it in line with the others.

So is it worth having this blade reworked for $29 as a spare?

[Dedpedal]

I would try it.

[twistsol]

I use Quinn Saw for sharpening and they do an excellent job. Their price for sharpening a 100 tooth blade is $30 and $5 to replace a tooth. By the time you pay for shipping, you'd be at the same price as new from Amazon.

I'd be concerned about the balance of the blade spinning at high speed with a tooth missing.

[LCHIEN]

I'm not too worried about the balance. Its only half a tooth out of 100 so a half a percent imbalance, And the weight of all the teeth is a small fraction of the weight of a 12" steel disk.plus the motor rotating mass, even though those are less than 100% of the radius.

[LCHIEN]

Left the blade off to be sharpened/repaired Tuesday.
Pickup/dropoff day is Monday every week so I hit the worst case cycle time. Be about 2 weeks before its back.

[dbhost]

I managed to break a tooth on a D1280X, basically the 80T version of that blade. I was cutting some maple and managed to find a piece of metal embedded in the wood that escaped the sawmill, and was discovered by my blade. That was blade #1 on my old HF 12" slider that is now in a friends shop... Blade #2 got transferred to my Metabo 12" slider with no damage...

I just chucked the old blade in the recycling and tossed the new one on. Didn't figure it was worth fixing, they are reasonably inexpensive and I had gotten a bunch of use out of the thing... Now I am wondering if I should have kept it and had it fixed...

[LCHIEN]

I got a new one (D12100X) for $60, overnight.

I figured I'll have the old one sharpened and basically fixed for $30 and have a spare blade with 98 or 99 of the original teeth sharp and ready to go.
A spare or one to check when I think the blade in the saw is dull.

[LCHIEN]

Got the sharpened blade back
Sharpening place and their price list both said $29 but Hardware store charged me $30, I should have complained.





Had black rubber coating protecting all the teeth (I started to peel it off before the pic)



Whatever they did they took of all the painted printing that said diablo



As it comes from the factory paint job that was still there when I sent it in,

They couldn't wash off the laser engraved serial no

and they engraved a invoice number on it



Teeth look pretty sharp. Had HiATB teeth from the factory, still looks wicked Alt Top Bevel.


Guess I'll try in the next few days and see how it cuts and if they straightened the bent tooth right.
Not too fond of the cosmetic disimprovements but I guess if it cuts OK its a pithy thing to complain about.

I like to keep my tools original looking. Am I too picky?

[LCHIEN]

Bad news - sharpened blade cuts like crap




The cut at the top was made by my new diablo blade, same model as the sharpened blade. Polished, clean, little tear-out.

The lower cut was made by the just sharpened blade. Not a smooth cut and huge amounts of tear-out.

I think I need to take it back.

[twistsol]

You should definitely send it back.

I recently took a blade to my Ace store who sent it out to a local place to sharpen it, thinking if it worked out well, I could save the round trip shipping to Quinn Saw. The results were similar to, but not quite as bad as yours. The blade seemed sharper but the cut quality had degraded significantly

It also looks like their scrubbing ruined the non stick coating on the blade. I'm not sure what they did that removed the coating around rim. In your before pictures with the exception of the broken tooth, your blade looks to be in quite good shape.

The heavily used blade below has been sharpened multiple times by Quinn without any of what I would classify as damage shown on your blade. Not that it matters, but they also engrave the blades, but in a much tidier manner.

[sweensdv]

I would definitely return that blade, horrible job. They made your blade unusable. I would say that if they can't fix their mistake they owe you a brand new D12100.

[capncarl]

As I previous posted in this thread, don’t expect much out of a re-tooth job for this cheap. If it was a jeweler doing it for $100 per tooth you MIGHT get a usable blade, or not.

In my previous job we had to do some pretty intensive repairs to cutter and grinder teeth, sprocket repairs, gear rebuilding etc. This was only on equipment used in our factory and never for sale. We employed top machinist, welders and milrights who could repair most anything. I have seen very large gear teeth completely built back by welding and grinding, but this took 100s of hours. To weld on carbide teeth I believe they were brazed or silver soldered on. These carbide bits were held in place with a pair of tweezers while welding. The best repairs that could be expected were a temporary patch until new parts could be ordered and built. This replacement could take many months and might require several more maintenance repairs before the new replacement arrives. None of these repairs would have been “pretty” like you would have expected your $100 saw blade to look like.

Saw blades with carbide teeth are built with every tooth welded on the blade and then they are all cut the same with a sharpening machine. These blades cost from $25 to $150 each because they are made in mass, Adding a carbide tooth is doable, but a single tooth replacement should cost more than the entire blade cost.

[LCHIEN]

I talked to the owner, he agreed to redo the blade.
He said that any teeth that were broken or bent to the point they stuck out and made a rough cut, would be ground down on the side so that they are not sticking out, as accurately bending a tooth back is risky and difficult.
He said that for 100T blade, loss of up to about 7 teeth if that many should still give acceptable performance.
I guess I'll find out in a few more days.

I think the way I screwed up this blade was cutting an aluminum extrusion. It was a thin extrusion but the blade was HiATB which are very sharply beveled for prescoring the grain and have very fragile pointed teeth.

I should have used a TCG triple chip grind...or maybe a FTG.

[LCHIEN]

Back from the sharpeners (again). Latest result they fixed the bad tooth on one side but not the other side... getting a really rough cut and splintering on the right side of the blade while the other left side is butter smooth.

Apparently they fixed the problem on one side, but not the other, even though I told them it cut roughly on both sides.

Talked to the guy, he's refunding my money. I guess neither of us want to deal with it. anymore.
Although he told me earlier they can fix minor problems, he now says that they are a sharpening shop, not a blade repair shop.
I think I see the bent tooth and he has a point, I damaged the blade (more than I thought) and they were willing to file down one bent tooth but not two.

[leehljp]

That is plum disgusting! Beauty and the beast of cuts! That bad cut is absolutely awful!

[LCHIEN]

The left side cut is not perfect, either.... my new blade does not tear out the back of the cut like this one does.
Anyway, this blade is going in the scrap heap after I take a quick look and see if I can identify the offending tooth that is apparently out of line. One bent tooth a few thousands to one side makes a 100T blade into a 1T blade, effectively.