Bent throat plate

[gwyneth]

Well, I celebrated the third week anniversary of setting up my new 21829 by bending the throat plate.

I was crosscutting about 1/2-1 inch off oak boards and I thought I heard a thunk, but with the earmuffs on it sounded like the dog had knocked over one of the many pieces of wood arrayed on my kitchen floor.

When I got back to the saw and turned it on for the next cut, something stopped the SMT. I looked at the right side of the throat plate was turned up about 1/4-3/8".

I unplugged everything, took the throat plate off, then the blade and guard/pawl/knife unit. The blade appears to be flat. It seems to make a very slight brushing sound when I turn it by hand--I don't know if it sounded like that before and I can't figure out where it's coming from.

I had to look back through more than two years of forum posts about ZCTPs and throat plates to find somebody else who's done this--somebody answering Loren's classic post about "Five things newbies can break". Unfortunately, he didn't say how he'd done it or what the ultimate affect, if any were.

Yesterday when I was in town, I stopped by the Sears dealer with the bent plate to see about ordering another. Sears dealers aren't regular stores--just a few actual products, franchised, and mostly an order/pickup service.

The guy who handles this stuff is gone until Wednesday, and the woman who was running things had me leave the bent plate (I had the part number and everything but she wanted the plate).

So, my questions are: assuming the cutoff got under the throat plate how could a small piece of oak get enough leverage to bend that metal all the way up front? Have I ruined anything besides the throat plate, and how can I tell? If not, should I just get a ZCTP and put it on?

Thank you, everyone.

[Popeye]

That's a new one on me, I don't have a clue how you could have done it.
I'd clear the area around the blade and turn the saw on, if it sounds fine then I'd install an ZCTP and keep on truckin. I was never fond of the factory TP's anyway. I made mine from 1/2" good plywood using a procedure on the site.
I rarely have anything on my saw but a ZCTP. Pat

[LCHIEN]

...

I had to look back through more than two years of forum posts about ZCTPs and throat plates to find somebody else who's done this--somebody answering Loren's classic post about "Five things newbies can break". Unfortunately, he didn't say how he'd done it or what the ultimate affect, if any were.

...
Thank you, everyone.

I looked - that was Final_t, he's still on here frequently,

Final_t?

Har to imagine how it could bend the plate up at that corner, but I imagine its ricocheting around inside the blade shroud at close to 100 mph it could have wedged itself anywhere.

[gwyneth]

It turned on fine...it wasn't until the upturned corner stopped the workpiece that I noticed.

I could see how a thin ripped piece might kick back, shoot under the plate and push/bend it. What probably happened is that the small cross-cut trim split--otherwise the discard would have been too big to get under the plate. But if it split (the end of old, dry but weathered oak) when it met the blade, one half must have been small enough to get partially under the plate, but not big enough to go through, and the force bent the metal enough to accomodate it.

That's just a theory. Since the blade didn't bend I'm hoping nothing else did, but the very faint brushing sound when I turned the blade by hand was making me wonder (it's very faint and may have been there before.)

I also hope the person who did it two years ago is reading and tells us how he did it.

Thankfully, the BT/Craftsman throat plate is rectangular and not curved--must make it infinitely easier to make at home.

[gwyneth]

Loren posted while I was writing my reply, so I didn't see it.

I was about to search again to find out who'd bent his, but, as always, you've saved time and effort. Thanks. Now to the FAQ to research making a ZCTP--then I'll ask about making an almost-ZCTP (can't use the saw without a plate and I don't think the raise-through-material would be a really good first thing to cut after such an incident.)

[cgallery]

The bent corner is at the front of the plate? I can't think of what would cause that, other than a cutoff being slammed down on TOP of the plate by the blade. But in that case the plate would also be caved in a little.

I know someone here will be along shortly and have a better idea of what happened.

[gwyneth]

The bent corner is at the front of the plate? I can't think of what would cause that, other than a cutoff being slammed down on TOP of the plate by the blade. But in that case the plate would also be caved in a little.

I know someone here will be along shortly and have a better idea of what happened.

Well, that whole side of the plate seemed convex or concave (can't remember which and the plate is sitting on some desk at the Sears dealer) but I didn't really notice that distortion until I took it off. The right front corner, however, is definitely bent up enough to halt the SMT.

[Popeye]

If this is the original factory steel plate then take a heavy hammer to it on as flat a hard surface as you can find. Should be able to make it flat enough to get you by while you're making a new one. Pat

[gwyneth]

If this is the original factory steel plate then take a heavy hammer to it on as flat a hard surface as you can find. Should be able to make it flat enough to get you by while you're making a new one. Pat

It was, but it being somewhere in the Sears system now, I'm going to use the circular saw/All-in-one clamp on what, by nice coincidence, is a scruffed old UMWH cutting board that is 1/2" thick, 15" long, and has a cutout handle that leaves--ta dah!--3" clear on each side.

This will allow two pieces 3" x 15". But I think I will cut the slot first with the circular saw/All-in one clamp and then cut the whole thing (couldn't fit the saw on with the all-in-one clamp on a 3" wide strip).

And finally a use for the cutesy Dremel plunge router attachment or router table accessory and the miniature router bits-- I can rout teensy rabbets on the end.

[steve-norrell]

It is a mystery how the steel throat plate could get bent. With all due respect to the speed and force of the saw blade, it would still take a tremendous force to bend the plate. Even more mysterious since you determined that the blade was not bent. Its also VERY scary!

Were there any teeth missing from the blade? Could the throat plate have moved while you were sawing? (Although I assume not since you probably had it screwed down.)

I attached a photo of the throat plate I made and use. They are also out of 1/2 UHMW. It was made with a router, using the saw only to cut it to size and make the slot for the blade.

Please keep us posted on possible solutions to the "Great Bent Throat Plate Mystery."

Regards, Steve

[gwyneth]

I agree on the very scary part, which is why I pulled it all apart.

The Freud LU86 showed no light when laid on a flat surface. But thank you, Steve, because I just typed "--and all the teeth are there" and then, just to be sure, went and looked.

A small amount is missing off one of the teeth. (Depending on blade terms, it might even be considered the tooth, if that makes sense.)

Now I'm really bummed out--wonder if this is a Sears warranty issue, a Freud/Amazon warranty issue, both or neither.

[steve-norrell]

I agree on the very scary part, which is why I pulled it all apart.

The Freud LU86 showed no light when laid on a flat surface. But thank you, Steve, because I just typed "--and all the teeth are there" and then, just to be sure, went and looked.

A small amount is missing off one of the teeth. (Depending on blade terms, it might even be considered the tooth, if that makes sense.)

Now I'm really bummed out--wonder if this is a Sears warranty issue, a Freud/Amazon warranty issue, both or neither.

Gwyneth,
You can look at picture or diagram of a blade to decide whether the carbide tooth is chipped or completely missing. The carbide tooth is soldered on to the blade body and could be a point of weakness. Fortunately, failure of the solder joint is a very rare event, but not unknown.

I don't know who would be resposible for the warranty, but I would try Sears first since that is where you bought it.

I would also be concerned about the "brushing" noise you hear when you hand turn the blade. Check it out carefully, then try to run the saw. Make sure there is no debris in the saw well.

Good luck! Regards, Steve

[gwyneth]

Thanks, Steve.

The blade came from Amazon and is also three weeks old. The Freud web site had this diagram of 'the pieces of a saw blade" and I've circled the part that's missing.

I don't know what caused what and how to explain this to the respective customer service departments...or whether this is actually a saw warranty issue or customer abuse (i.e., putting a defective blade on it).

Clearly the saw blade is covered under Freud's warranty but if it was all the blade's fault, saw damage probably not covered unless Wisconsin has one of the 'other provisions in some states' that the Freud warranty mentions.

I haven't really talked to Sears--just told the woman there I wanted another throat plate. So I've got to figure out what to say to the local guy tomorrow and perhaps central customer service.

I've poured through the saw dust on the floor, cleaned the saw well, and am about to look through the shop vac to see if I can find the errant tooth, because it just occured to me that it may have flown into some place in the motor assembly and is causing the slight 'rubbing' sound.

[steve-norrell]

G:

"I looked at the right side of the throat plate was turned up about 1/4-3/8"." . . . and . . . "So, my questions are: assuming the cutoff got under the throat plate how could a small piece of oak get enough leverage to bend that metal all the way up front? Have I ruined anything besides the throat plate, and how can I tell? If not, should I just get a ZCTP and put it on?"

Based on your statements it looks as if the TP could also have been hit from above -- the right side could appear to be "turned up" by something pushing down from above. Since the front half of the blade is moving down (at least over the front half) it becomes a suspect.

Another possibility is that something resembling a kick-back occurred because of the missing tooth -- either by the tooth itself or by the part of the blade that it was missing from (see comment by cgallery). If it was the tooth, I can't imagine that there would not be visible evidence (chip, gouge, etc) in the TP.

A third issue is that if you were using the original equipment throat plate, the space between the blade and the edges of the TP are too large for the blade to hit unless there is obvious and tremendous blade wobble -- something you seem to have eliminated. That leaves some kind of really heavy-duty kickback as the likely culprit.

If it were me, I would try to determine if the saw itself was in good shape and follow Popeye's suggestion (after getting the plate back). If I had any reservations about the saw (couldn't resolve the "brushing" sound) I would ask Sears to take it back and replace it with a new one.

Good luck, Steve

[crokett]

just occured to me that it may have flown into some place in the motor assembly and is causing the slight 'rubbing' sound.

Turn the motor with the blade off the saw. If the blade is causing the rubbing then you won't hear it with the blade off.