Review Lenox 14" diamond cut-off blade

[Kozzy]

After these were mentioned in another posting, I decided to give it a shot just to see if the hype lived up to the product.  I picked up a 14" Lenox diamond blade from the internet mega-store:  Price $ 80.  My comparison was to DeWalt abrasive cut-off blades (virtually brand new) which can be had at most big box hardware stores and run about $6 to $7 at the internet mega-store.

Saw is a Milwaukee standard 14" abrasive cut-off that's about 15 years old.

First, there is one difference you notice right away:  Inertia.  The diamond blade is a lot heavier and the inertia when starting the saw makes things really jump.  When stopping, the inertia keeps the blade spinning quite a bit longer than the standard abrasive blade.  That inertia is enough to make your heart jump a beat but probably something one would get used to quickly.

For cut tests, I used 2 x 3/16 HRS flat bar and 1-1/4" 430 round bar.  I did some rough timing of the cuts, trying to keep things as similar as possible but that part is pretty subjective.

A few photos:

Diamond cut (left or top...it moves when actually posted) and Abrasive cut (right or bottom) in 4130.  Bar got darned hot with the abrasive wheel so showed some coloring as it cooled.  No big deal except in comparison

Round bar discs that were cut off.  Abrasive on left, Diamond on right.  Abrasive took 43 seconds, diamond 44 so it's a tie.  Diamond had a lot more smearing and rougher cut. The color on the diamond cut seems to be an artifact of the first abrasive cut--where the bar on that first abrasive cut got coloration, the slug didn't.

 

Flat bar cuts, Diamond on the left and abrasive on the right.  Very similar results but the diamond was a rougher cut and left more of a lip on the bottom.  Because the first diamond cut heated the bar enough to color, I did a second and on that one it didn't.  Cut time on diamond, 21 and 16 seconds..Abrasive 13 seconds.

Some conclusions:

Cuts are definitely more rough with the diamond blade.  You don't use this kind of saw for precision cuts anyway so maybe that's not a problem but it would require a bit more clean-up.  Speed is roughly the same between the two with diamond actually taking a hair longer.  The difference is not enough to attribute to the blades rather than the tests/operator.

Noise:  The diamond is a bit louder in my opinion.  Not a huge difference but with even a single cut you don't want to forget ear protection.  With abrasive, it's just enough quieter that I'd only normally grab ear protection for long or repeated cuts and might let a single cut slide (bad on me).

Sparks:  Diamond did throw less but it still throws enough hot stuff that you need similar precautions to that of abrasive.  I assume with the wheel not degrading as you go, there is less "dust" (as the literature claims) but I didn't run enough to compare.  Less of that abrasive crud flying around might be a huge benefit to those with smaller shops..it seems to get everywhere.

In my opinion, the only significant benefit to diamond would be in blade life.  That might benefit a production shop that does cuts all day long but for the average guy, it wouldn't be a huge deal.  By the advertising numbers ("lasts 30 times longer"), over the life of the blade the diamond would cost you about half as much but who does that many cuts in the situations amateur smiths normally see?

The real cost to diamond is in more ragged cuts.  In many situations this may require a lot more time dressing the parts after the cut. 

As an aside, there are some notions that you could cut stuff like bricks once in a while which might benefit smiths on the rare occasions.

I'll leave it on the machine...but I'm not particularly thrilled with the results and don't think I could recommend one.  There is no significant benefit over the cheap abrasive blades. I didn't have any really hard material to try (couldn't find my stellite) and there may be some benefits to those running really hard stuff.  I have a diamond wet saw for that so it's not of benefit to me.

The horizontal band saw still gets my vote for 99% of metal cut-off.

 

[Buzzkill]

I have only used the 4.5 cutoff disks of the same brand.  My conclusions are similar to yours as far as speed and roughness goes.  However, in a hand-held tool the chance of the disk turning into flying shrapnel being pretty much eliminated is a big deal to me.  I also appreciate that the disk isn't decreasing (not enough to notice anyway) with use which can be really annoying when you're almost done and have to change to a new one.  On balance I lean more towards the diamond edge cutoff for hand-held angle grinders, but as you indicated there is still the issue of slightly more time and rougher cuts.

1 hour ago, Kozzy said:

The horizontal band saw still gets my vote for 99% of metal cut-off.

Agree 100% .  If it will fit in the horizontal bandsaw and the blade will cut through it I'll choose it every time.  It's the only power tool I own that I am comfortable walking away from while it's in operation.  The cuts are fairly smooth, square, and only slightly warm even without fluid. That tool was one of those "where have you been all my life" acquisitions.

[Anachronist58]

Excellent Review, Kozzy, and I believe that I am in complete concurrence with your assessment. The noise for me is terrible, and I am not thrilled by the raggedy cut. That rough cut was also throwing out chunks, which was not particularly pleasant.

I will see how my 4-½" Lennox works on brick - I think that I will do that right now.......

Passes through hard fire brick like butter, cuts cool and easy through high-iron gabbro, no heating of the blade.

For twelve bucks, I think I have found myself a new stone disc.

I would be surprised if the Freud Diablo did not perform equally as well as the Lennox.....

Buzzkill, how is your blade life so far?

As far as band-sawing goes, my portaband is the go-to for me.

Robert Taylor

[BIGGUNDOCTOR]

Staying the same diameter is a plus for the diamond.

At work for flat I found cutting it on edge went a lot faster and the diamond blade did not wander side to side.