Diamond Metal Cutting Blade

[Ralphxj]

Does anyone have any experience using Diamond Metal Cutting Blades in place of abrasive cut off wheels on gas or electric saws? I have a project that involves cutting up a BUNCH of metal grating and in the past I've been using diablo abrasive cut off wheels in a 12in electric saw (Hitachi CC12Y). I go through a bunch of them and I'm intrigued by the diamond blades claims of having 100x the life of an abrasive wheel. Even at 25x the life I would spend the same amount and not have to stop to change blades so often. Do they work as well as they claim? Are they worth the money??

This is the type of blade I'm looking at: https://www.homedepot.com/p/Hilti-12-in-x-1-in-SPX-Diamond-Metal-Cutting-Blade-2200899/306890638

Before I get 50 replies about other types of saws/cutting, this the method that works the best/fastest for what I'm doing, I've tried MANY other ways. So not looking for other types of cutting, just looking at blades for this saw.

 

[Ign]

I've used the Milwaukee version for 4.5" grinders.

It works well enough, honestly couldn't say why exactly but I'm just not that thrilled with it. Puts off a weird, very fine metal dust.... different than abrasives.

That said, for your application I think you should try it.

 

[Ralphxj]

I've used the Milwaukee version for 4.5" grinders.

It works well enough, honestly couldn't say why exactly but I'm just not that thrilled with it. Puts off a weird, very fine metal dust.... different than abrasives.

That said, for your application I think you should try it.

I've seen a lot of reviews on the small discs and they seem to work well. The price tag of the big discs has me concerned. Hate to drop $150+ on one and not get comparable cuts (speed and quality) or poor life out of it.

 

[bimmer1980]

I have cut metal with the abrasive blades on a 12" Stihl gas demo saw.... It does **** when the blade reduces in diameter.

I have cut cast iron with the Lennox diamond blade in a 4.5" grinder. It was awesome! With that experience and a lot of steel cutting ahead, yes, I would be willing to try the 12" diamond blade.....

Your time and hassle is worth something too.... blade changes, dust, etc.

I also like the idea of minimal blade diameter reduction... That was the biggest hassle in cutting bar and tube with the abrasive blades on the demo saw....

 

[cjarvis]

My experience with the 4.5” Diablo diamond cutoff wheel was that it does last significantly longer than abrasive discs but that they took longer to make the same cut.

 

[Ralphxj]

I wear a full face mask respirator so the smell and dust isn't a concern.

My experience with the 4.5” Diablo diamond cutoff wheel was that it does last significantly longer than abrasive discs but that they took longer to make the same cut.

I guess I can't expect them to be faster, last longer and be cheaper. Cutting speed is a concern, but if I can avoid changing discs every 3 minutes a slower cut speed would be ok if they truly last a LOT longer and end up cheaper.

 

[rsanter]

I use the ones for the 4.5" and love them.
I have one of those lifetime guarantee ones from bad dog and they have already replaced it once after around 3 years of hard use. They replaced it no issues.

I also bought one of the lennox ones.

The Lennox is a thinner and is cut only.
The bad dog is thicker and can be used as a grinding wheel. I have not bought a hard grinding wheel in over 5 years as I use the hell out of the diamond one.
I have used it for steel and bricks and it just keeps going

Bob

 

[Ralphxj]

I use the ones for the 4.5" and love them.
I have one of those lifetime guarantee ones from bad dog and they have already replaced it once after around 3 years of hard use. They replaced it no issues.

I also bought one of the lennox ones.

The Lennox is a thinner and is cut only.
The bad dog is thicker and can be used as a grinding wheel. I have not bought a hard grinding wheel in over 5 years as I use the hell out of the diamond one.
I have used it for steel and bricks and it just keeps going

Bob

That Bad Dog blade looks awesome! Wish they made one in 12in! What saw are you using with yours??

 

[neophyte]

The diamond cutting blades for steel supposedly take longer to make the same cuts as regular abrasive discs. And the extra amount of time is enough that it might not really save any time over changing out discs.
There are some timed reviews on Youtube.

The main advantage I’ve seen to the steel backed diamond discs is there much less likely to break in use, so would be safer for awkward cuts that could cause a disc to fracture and explode,
The other advantage is the discs likely don’t gave an expiration date, after which the bonding agent might gave failed, and the discs are likely more stable than bonded fiscs under adverse environmental storage and use, such as high humidity or heat.

 

[pcmeiners]

Experience with 4.5" and larger. Two negatives with hand held devices, the diamond area of the blades tend to breakup if jammed or misaligned under power; face shield definitely needed. The other issue, diamonds burn up when heated so the blades do not last long without water cooling. Other than that, a 4.5" on a hand held grinder works wonders on many materials, I buy cheap blades as I expect to have them breakup before they wear down.

 

[Chuck122]

I tried a hilti 4.5 blade and i was not really impressed. They do last a long time but they don't cut as quickly or cleanly as quality abrasive disks. They are less mediocre on thinner, sheet metal stuff or grating than on the thick stuff. The main advantage is that the disks don't get any smaller with wear so you don't need to change disks because you need all the depth of cut and the disk has gotten too small.

 

[rsanter]

That Bad Dog blade looks awesome! Wish they made one in 12in! What saw are you using with yours??

All of my grinders are desalt and Fein

 

[rsanter]

The diamond cutting blades for steel supposedly take longer to make the same cuts as regular abrasive discs. And the extra amount of time is enough that it might not really save any time over changing out discs.
There are some timed reviews on Youtube.

The main advantage I’ve seen to the steel backed diamond discs is there much less likely to break in use, so would be safer for awkward cuts that could cause a disc to fracture and explode,
The other advantage is the discs likely don’t gave an expiration date, after which the bonding agent might gave failed, and the discs are likely more stable than bonded fiscs under adverse environmental storage and use, such as high humidity or heat.

The bad dog one is thicker than usual so it is a way better grinder than it is a cutting disc for metal. For thin metal it does not matter much as it eats it up but for thicker and harder metal it does take longer.
That's why I bought the Lennox version which is much thinner. I still think it goes slower than an abrasive cut off disc, but the fact that it lasts a long time, does not reduce in diameter and will not come apart like the abrasive ones can, in my mind outweight the longer time.
The key reason I use it is for cutting thicker stuff or hard material as for most other things I have a plasma cutter.

 

[Ralphxj]

Looks like I can get a Lennox blade for my saw for $77, so not as big of a purchase as the $195 Hilti!! The abrasive ones are $6, so it wont take much to save some money, and if its TOO slow, I only need it to last as long as a few abrasives and then I'll switch back.

 

[Ralphxj]

Figured i should update this with how things worked out! I picked up the Lenox blade (#1972930) for $76. So far I've made approximately 42 cuts through 4ft of the grating in the photo. Before I would get approximately 3
cuts down the 4ft sections with each abrasive discs. So at $5.97 per abrasive discs, I've saved $20 already and the Lenox blade is still cutting great!

 

[Paul_The_Builder]

I have one for a 4.5" grinder, and I don't care for it. Its much thicker than an abrasive cutting disc, and cuts a lot slower and creates more heat. Also useless for cutting aluminum.

For a large diameter disc doing a lot of cuts into steel, I can see where it could be the right tool for the job though.

 

[rlitman]

Experience with 4.5" and larger. Two negatives with hand held devices, the diamond area of the blades tend to breakup if jammed or misaligned under power; face shield definitely needed. The other issue, diamonds burn up when heated so the blades do not last long without water cooling. Other than that, a 4.5" on a hand held grinder works wonders on many materials, I buy cheap blades as I expect to have them breakup before they wear down.

I don't do too much cutting with these discs, but I bought a 4.5" diamond wheel a few years back, and have not used an abrasive slicer since.

My diamond disc is a little thicker than my good abrasive wheels (Metabo was my favorite). The diamond seems to cut a little slower, but I'm not sure if it's actually slower, or if it's just my perception due to the fact that it throws less sparks, since it isn't eroding. And also, abrasive wheels slow down as they shrink (since the edge speed decreases with diameter), while the diamond doesn't have this issue.

Anyway, I really meant to reply to the diamond burning up issue. While it is possible to burn up diamonds, that doesn't happen cutting steel. By the time a diamond gets anywhere near the point of combustion, the steel will have already burned away long before (which coincidentally happens to be a good way to cut steel).

What does happen (and why surface grinders don't use diamond on steel), is that the steel actually bonds to the diamonds, shortening their life. But that's not the issue here.

Metal cutting diamond blades are designed a little differently than their stone cutting older brethren. The heat issue is with how the diamonds are bonded to the plate. Stone cutting wheels do run cooler. In fact, many water cooled diamond tools are actually made from plastic! The air cooled discs have spaces that pull in air, but such designs would kick-back on steel, which is why the really cheap diamond discs shouldn't cut steel.

What makes steel cutting diamond wheels special (read, expensive) is that they bond the diamonds in a way that is more heat resistant than the stone cutting wheels, while still being able to be air cooled.

...Also useless for cutting aluminum...

And? Abrasive cutoff wheels are also useless on aluminum. Aluminum buildup on abrasive wheels is a major cause of wheel explosions. I own a few aluminum rated abrasive grinding wheels, but do not recall seeing any aluminum rated abrasive cutting wheels. Plus aluminum cuts faster with a jigsaw anyway.

 

[2oolhound]

Figured i should update this with how things worked out! I picked up the Lenox blade (#1972930) for $76. So far I've made approximately 42 cuts through 4ft of the grating in the photo. Before I would get approximately 3
cuts down the 4ft sections with each abrasive discs. So at $5.97 per abrasive discs, I've saved $20 already and the Lenox blade is still cutting great!

Thanks for the update, good info to know.

 

[vanapplebomb]

My experience is that they work awesome for mild and medium carbon steels! It is my go to cutter for those materials. Less mess than abrasive discs, and just as fast. Safer too, because they won’t break up if you accidentally bind and flex the disk. The lifespan of them is pretty incredible, and it more than makes up for the initial cost.

They are pretty hopeless with stainless though…makes a lot of heat and noise, but not much action.

 

[Steve_P]

I like the Lenox diamond blades. I don't buy them for the cost vs lifespan, I don't care about that, I buy them for my personal safety. We use them at work and they cut SST pipe just fine.

 

[The Cobbler]

I also have good luck with Lenox diamond metal blades

 

[Jlarson]

We run diamond multi material blades on 9" and 14" saws. Mainly cutting rebar, pipe, stock and grate, way better then changing abrasive all the time, good abrasives still probably win speed wise in plate cutting but that's not what we normally use rescue saws for.

The multi material blades also see a lot of use on PVC jobs.

 

[dnschmidt]

Seems like a job for either a cutting torch or a plasma cutter.