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Bought the Dewalt DWS780 miter saw a couple of weeks ago. Was really enjoying it until a couple of days ago. Was cutting a piece of pine 5 inch trim, on the saw in a north south orientation, up against the fence. Had it mitered 45 degrees to my left. Half way thru the cut, there was a huge noise and the saw came to a dead halt. The trim in my hand exploded. My hand was bleeding badly, pointer finger mangled up. The saw blade was warped and had cut its way into the cast housing that wraps around the top of the blade. No idea what I did wrong. Any ideas?
 

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Close call Yank, ouch. :banghead::banghead:

No clue, don't know anything about miter saws, but I'll be following this thread.
 

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Wow! That’s pretty serious. Have you contacted Dewalt and shared the pics?

Did you go too fast with the blade?

Perhaps the blade failed. It looks like the blade started cutting into the casting right where the blade had a relief cut into it. Those are for noise and vibration reduction as well as to deal with expansion as the blade heats up. Do you have pics of the wood?
 

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Close call Yank, ouch. :banghead::banghead:

No clue, don't know anything about miter saws, but I'll be following this thread.
X2. Just glad you have a finger to wrap.
 

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It looks like the blade came loose. I spent the better part of 30 years using those professionally without so much as a scratch and then got nailed twice in 6 months both from being less than focused. I've only seen 1 12 inch miter blade come loose in my career and it had similar results. We determined it wasn't tightened properly when it was changed.
 

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Let me answer some questions here. Blade was tight, still on the bolt with nut tightened down. The blade warped that much to cut into the cast metal. Quite incredible. No pics of the wood because it looked like toothpicks. Literally exploded. My finger never touched the blade. The wood exploding in my hand is what cut me. No nails or metal in the wood. It was brand new trim. I have no idea what happened.
 

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Diesel, blade failure could be the answer. Took the saw back to Lowe’s. They are sending it back to Dewalt and a representative is going to be contacting me.
 

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I would like to see the whole blade and some closeups of the failure point. Make sure to take lots of pics (for yourself) when and if you take it apart.

I’d definitely be contacting Dewalt and letting them know.

*Edit* we were posting at the same time.

Make sure to document everything. Lots of pics. Now that the saw is gone, you only have what you documented. I’d like to see them take care of you and the the potentially dangerous blade/saw.
 

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X2. Just glad you have a finger to wrap.
The first thing I did was thank the Good Lord I still had a finger. I have to admit, it scared me. Shook me up badly.
 

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It looks like the blade came loose. I spent the better part of 30 years using those professionally without so much as a scratch and then got nailed twice in 6 months both from being less than focused. I've only seen 1 12 inch miter blade come loose in my career and it had similar results. We determined it wasn't tightened properly when it was changed.
^^^ I"d have to agree with this. There is usually a good sized gap between the blade and that housing/shield. You'd have to have some SERIOUS warping to bend a blade that much and it would be something you'd notice. Your kerfs would be 1/4" wide. But if a blade starts coming loose... then you can get a lot of wobble and I can see that sort of thing happening.
 

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Let me answer some questions here. Blade was tight, still on the bolt with nut tightened down. The blade warped that much to cut into the cast metal. Quite incredible. No pics of the wood because it looked like toothpicks. Literally exploded. My finger never touched the blade. The wood exploding in my hand is what cut me. No nails or metal in the wood. It was brand new trim. I have no idea what happened.
Hitachi makes very good products but none are fool proof. I've honestly never seen a sawblade we use fail like that in hundreds if not thousands of them.. They do warp from heat cycles and get curvy when they cut at the end of their life but material failure? I never seen it. I'm glad you weren't seriously hurt. Those saws have little forgiveness and zero sense of humor.

Um, please correct me if I'm wrong but that saw didn't come with a Hitachi blade. If DeWalt determines the blade failed, it won't be on them. Ill be very interested in the outcome of this, if there is indeed one. If you don't mind me asking, how did you determine the blade was tight with the blade jammed in there like that? For what it's worth, because of the way the blades are secured, it it possible for the tension washer to be out of alignment and seem tight until the blade spins up and makes contact, similar to a mower blade. Both use similar systems to secure the blades.
 

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Glad to hear you're OK. well no loss of any fingers.

With my Hitachi miter saw, if I cut on a angle or slope cut (wrong wording) , I have to move the back bracket on the miter bench..

Just wondering did the blade hit the back of the miter bench before warping the blade and stopping the blade.
:dunno:
 

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That's scary as hell Yank!!

Glad you came thru it with apparently a minor injury from what could have happened.

Let us know DeWalt's finding.
 

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I did notice from your picture it was not a Dewalt blade. What brand was it? Just curious.
I saw that also. It looks like blade was not tight.


I have used many power saw and I some time think I over tighten the blades.
 
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