(about 1 year) of daily regular use cutting mostly hard wood.

Just 3 hours a day actual cutting time, 5 days a week, 50 weeks in that year, equals 750 hours cut time on the blade. It is NOT new and yes it needs replaced or sharpened.

 

Looks gummed up and most likely dull from the effect on the wood.
New blades are reasonable from the Home Center or Amazon.
Have it sharpened IF you have a known good source.
I've had My thin kerf Diablos sharpened and they cut great.

 

With the OP being in Brazil, Amazon is a good candidate!

 

Get sharpened and flattened or replace it. When I was running my shop on a regular basis I used, and still use, Forrest blades. Arguably the best carbide used. My blades got rotated and shipped out for service every 3 months. It is not just the wood, the tannins can pit and eat the carbide, especially lower quality carbides.

 

I think the first step would be to clean the blade. It looks terribly pitched up. I clean my Freud blades by laying out a garbage bag on the workbench and spraying a liberal layer of 409, or some other cleaning product, on one half. I then lay the blade in the "puddle" and give it a liberal coat of the cleaner. I fold the remaining half of the trash bag over the blade and leave it overnight. Next day, I scrub the blade with a brass bristled brush and rinse it throughly. I clean the blades before giving them to the sharpening service. A clean blade always cuts better.

 

The first step is to throw the blade away. The saw shop I use won't sharpen that blade. I think those blades are a good value, but their disposable. I have one and use it until it begins to to leave a rough cut, then toss it. I do clean it.

 

I've used Freud blades alot and I never thrown one of them away. The sharpening service i use actually puts a better edge on my blades than when i purchased them, I've cut plywood with cabinet liner on both sides with absolutely no chip out.

 

Definitely needs cleaning and that will help, but yeah, I’d say it’s dull.

Cover the sled fence and base with 1/4” MDF or ply to create a new zero clearance kerf line.

 

#1..Why I don’t buy Freud. Too unpredictable.
#2. Forrest is far on bring superior. When I started looking at forums in 2000, that’s all I heard about. With the internet, the same blade those pro’s use became available.
#3… Regardless of what blade you buy, you should have a reputable shop to sharpen it. They mostly use CNC equipment t sharpen just like Forrest..

 

Try here …

https://www.amanatool.com/

Scan down till you see saw blades, click..

 

Two things that I have noticed in the pictures one slide is got a lot of burning pitch build up around the blade opening.
The other is the condition of the cutting teeth I understand the picture resolution is not the greatest but it did shows it relatively well it shows a lot of teeth are rounded over.

Most Blaze the coating like a paint helps with throwing the wood dust chips out away so it doesn't stick but it looks like the blade is been hot number of times.

It is unusual to see the paint coating chipped out like shown in the picture.

Also your zero clearance the sled has been compromised which is adding to your splintering problem.

 

He eithe4 needs another blade or re sharpen. you can get splintering from a lot of things..

 

Wow, a lot of great advices! I will try to answer the comments in a single message. First of all although I have been around wood my whole life just very recently I left my day job (kind of a forced retirement) and embraced the wood working as a profession for the rest of my days. This is the explanation why I am an idiot regarding to some basic knowledge such as the endurance of a blade. I think that within my innocence I imagined that blades were something to last forever, LoL, or at least a lot more than one year! Anyway, I checked when I bought it (it was exactly one and a half year ago) and after doing my math I think that this blade has worked something around 350-400 hours. Now I know that getting to this – and still more important – when it starts to blow the wood in cross cuts is time to put it away and replace with a brand new one.

After reading your thoughts and knowing that the blade is near to death, this is my plan: currently I have two table saws, both with the same blade (Freud 40 teeth) being the second a lot less used than the first. Because I use the second table saw mostly for resawing and ripping, I am going to replace the 40 toothed blade with a brand new 24 one that is still in the package AND will move its 40 teeth blade to the other saw where I do my cross cuts using a sled. I believe that it per se will improve the results a lot. then I will try to revive the old blade by cleaning it, although I am not too hopeful due to its conditions. Unfortunately we don't have the 409 here in Brasil – in fact we have in Amazon as someone mentioned, but it's absurdly expensive – however I think that any general use degreaser will do the job, so I am going to try it. Being ignorant in such aspects I never knew that there are different blades for different cuts but now I know it and I am planning to buy a cross cut blade as soon this "new" 40-teeth start to fail, as I remember that yet not being ideal for the purpose, when it was brand new it was able to perform very decent cross cuts.

Unfortunately being in Brazil I don't have a plethora of options in term of blades to choose among. There are a ton of crappy brands, plus Bosch and Makita (that regardless the brand I don't like too much, given my past experience with bits and jigsaw blades) and we have Freud that is basically the best we can get here without having to import. So I think I will have to stick with Freud.

Finally I am trying to see if sharpening blades is something that will pay for itself, considering that someone has told that this blade is kind of disposable. A brand new Freud here will cost me around $60 while I am supposing that a sharpening service will not be less than $25 plus the hassle of bringing the blade and then going again to pick it. Finally I never tried a resharped blade but I could bet that it won't turn the blade back to the brand new condition and I could double bet that it certainly will get dull again in a lot less time. So maybe it won't make up, I don't know, still have to check. In any case I think THIS blade is too much damaged and won't worth any try, so I may just dispose it.

Thanks for all valuable inputs!

 

Well I replaced the blades:

The one on the sled saw is cutting a lot better now, although I am aware that the disc is already asking for a cleaning:

And here is the bad blade. I think it's in so horrible shape that I am no sure that a cleaning will help. I realized that some of the carbides even have small pieces chipped out meaning that the disc may be irreversibly damaged.

 

Regarding cleaning the blade, if you don't get great results with a regular degreaser, I suggest trying Laundry Detergent. I use an old oil drain pain to hold my saw blade, drizzle a little bit of laundry detergent on all of the teeth (flip and repeat on the other side), let the detergent sit for 5 minutes, add in some hot water, let it sit for another 5 minutes, then brush with a stiff bristle toothbrush making sure to make every surface of every tooth shine.

I think you've already picked up on this, but I want to add that the blade needs to be cleaned anytime there's a buildup of gunk on the teeth. The buildup will cause the blade to cut poorly, but also cause excessive heat buildup which will make the teeth themselves more vulnerable to actually getting dulled.

Last thing to mention is just to make sure that the blade is completely dry after cleaning. I think some people might hose it down with WD-40, but I get it as dry as I can by hand then mount it to the saw and run it for a minute to fling off and air dry any water that might remain.

 

Having just cleaned a used 10" saw blade that came with a table saw purchase, I used the lid from a 5 gallon Home Depot bucket and Purple Power cleaner.
Purple Power is a more powerful cleaner than Simple Green which others often use.

Purple Power 128 oz. (1 Gal.) Industrial Strength All-Purpose Cleaner and Degreaser Concentrate 4320P - The Home Depot

Purple Power has been the #1 purchased brand of degreasers nationwide since 2003 (in the automotive aftermarket, as rated by the NPD Group). This powerful cleaner and degreaser penetrates grease, oil and dirt on contact, wiping away even the toughest stains in just seconds. Clean carpet...

www.homedepot.com

The blade fit within the lid with enough room to scrub the teeth with a brass brush.

As far a sharpening any carbide tooth blade, even the Diablo's can be sharpened with their small teeth, at least once, maybe twice?
I had mine done at 1/2 the cost of a new one.
The important thing to know about any carbide blade is the type of carbide used on the teeth.
The lowest grade carbide used on saw teeth is C3.
The more expensive blades use C4:

10" X 48T Rip and Cross Cutting Table Saw Blade for Softwood (TS2000)

For use on soft wood. ATB Top Grind providing low cutting pressures that reduces material tear during the cutting process. Combination rip and cross cuts for a smooth cut finish. Carbide teeth are ground to a 1200 grit for a razor sharp finish. This blades micro-grain carbide tips are 1/3...

ridgecarbidetool.com

C-4 Micro-Grain carbide tips 1/3 larger than the best known blades

Surprisingly, this cheaper, Harbor Freight blade also has C4 carbide teeth:

https://www.harborfreight.com/power-tools/power-saw-blades/circular-saw-blades/10-in-40t-general-purpose-miter-and-table-saw-blade-63801.html

 

If you need to clean it, you probably need to have it sharpened.

 

If you need to clean your blade it's because it's gummed up with pitch and resin.
Hardwoods won't typically have much pitch in them, mostly soft woods like Pine and Fir etc.
That will cause them to heat up and not cut well, even though they are still sharp.
I don't need to sharpen my blades after cleaning because they always cut more efficiently.
Depending on the number of hours, the type of wood, and an increase in feed pressure, I know when it's time to swap out that blade for a sharp one.

 

I would talk to the blade sharpener and get info on how to tell…Most are informative..

 

Pitch and resin can sometimes (pine certainly can) be cleaned with acetone, or nail polish remover. Outdoors. In Brazil, where labor is cheaper than goods a lot of the time (my brother used to work for Embraer...), it may well pay to find a good sharpener, or to learn how to sharpen it yourself.
I by no means can comment on the amount of work you've done with that blade, I'm not even in the same house with that amount, never mind the same room. But acetone does clean pine pitch, and skilled labor can be very cheap depending on where you are.
Wendy P.

 

I believe the location he is at is the country Brazil so the ability to get sharpening done locally Maybe a bit of a challenge.
Living in Florida my nearest sharpening place is almost 2 hours away there is one that's closer but only does commercial work 16 inch blades and larger that pretty much eliminates the DIY person weekend hobbits, small woodworker.
There is a small family one in North Ocala Fla, somewhere I forgot where it's at I didn't find their websites so they might be gone or just not very obvious