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chris dub
07-03-2008, 8:26 PM
I was trying to change the blade on my Miter saw and snapped the head off the arbor bolt. So now I have a bolt shaft stuck in the arbor.
Does anyone know how I can get the shaft out? It is a dewalt DW703 if that makes a difference. I'd prefer not to have to take it to a repair center.

Dustin Thompson
07-03-2008, 8:31 PM
Crapsman makes screw extractors-they sell them at Sears.

Good luck,

Dustin

Chris Kennedy
07-03-2008, 8:50 PM
I am not familiar with the DeWalt, so this may not be physically possible. If you can easily access the top of the bolt, using a punch you can strike and rotate the bolt. If you can break the bolt free, you may be able to spin it out either by hand or with a pair of pliers.

Hope this works and good luck.

Cheers,

Chris

Gary Lange
07-03-2008, 9:07 PM
With a center punch mark a whole in the very center of the broken bolt. The drill a small hole in it to make sure it is centered fairly well. Now drill a larger hole nearly the size of the bolt and with an easyout remove the bolt. Be very careful ti get it centered properly.

chris dub
07-03-2008, 9:10 PM
Are arbor bolts typically repalceable with bolts that you find at the local BORG or Hardware store?

Gary Lange
07-03-2008, 9:27 PM
Chris, perhaps these people have the part you need. It looks to be part Number 21 and costs .92 cents but also looks like any other bolt with a built in washer. I would look at a Auto Parts Store maybe. You could just order this if you can't find one around you town.

http://www.ereplacementparts.com/dewalt-dw703-type-inch-compound-miter-saw-parts-c-1009_1163_2579.html?osCsid=e33d71d01f90772de9f10f7 edafb5152

Bob Wingard
07-03-2008, 9:33 PM
You ARE aware that the 703 is a left-hand thread ??

chris dub
07-03-2008, 9:52 PM
I wasn't aware that is a left thread. I will be calling Dewalt for a replacement part. I would hate to break the saw or worse have spinning blade fly off at me.

Steven DeMars
07-03-2008, 10:03 PM
You ARE aware that the 703 is a left-hand thread ??

If it is a left handed thread, I would center punch it and drill a 3/16" hole in it . . . drill very slow with steady pressure & I'll bet the bolt comes spinning out before you finish . .

Mitchell Andrus
07-03-2008, 10:37 PM
Drill, tap and insert a NORMAL bolt. It's left handed, no easy-out needed.

chris dub
07-03-2008, 10:58 PM
What's the signifigance of the left thread? And by tapping do you mean tap it with a center punch? Or does tapping mean something else?

Thanks for all of the advice so far.

Mike Henderson
07-03-2008, 11:12 PM
What's the signifigance of the left thread? And by tapping do you mean tap it with a center punch? Or does tapping mean something else?

Thanks for all of the advice so far.
In this case I believe he means take a tap (which cuts threads in a hole) and thread the hole. Then put a right hand bolt in (same size as the tap). When you tighten a right hand bolt, it will tend to unscrew a left hand bolt - the one that's stuck.

BTW, the reason they're called "right hand" and "left hand" is as folllows. Assume a right hand bolt - take your right hand and point your thumb in the direction you want the bolt or nut to move. The direction of your fingers will tell you which way to turn the bolt or nut.

When you have a left hand bolt or nut, use your left hand the same way - point your thumb in the direction you want the bolt or nut to move and your fingers will tell you which way to turn.

Mike

[The reason you have a left hand bolt on that saw is that the bolt tends to tighten when you start up the saw. If you had a right hand bolt it would tend to untighten. I would purchase a replacement from DeWalt. Those bolts are heat treated and you want the same kind, and strength, bolt to replace it. I would not recommend a cheap Borg bolt for that - if you could find a left hand bolt at the Borg.]

chris dub
07-03-2008, 11:37 PM
Steven was right. I used a metal drill bit and the notch on the tip of the bit and it provided enough surface to move the bolt and spin it out. I broke the bolt using an impact wrench to get the bolt off that was on way too tight. I couldn't get it off by hand or with my 18V drill. But the impact wrench losened it up. Jut a little to strong I guess. I should have stoppped as soon as I got it to budge. I'll order the replacement bolt.

Guess I'll have to wait to try the new blade. Too bad I was anxious to check it out.

Thanks all.

Johnny Pearce
07-04-2008, 12:50 AM
Chris, If you live in or near a town of 50K or more, there will probably be a bolt and screw store. Take your 2 pieces of the bolt in and I bet they can provide you with an exact replacement. Johnny Pearce

Roy Harding
07-04-2008, 12:57 AM
Steven was right. I used a metal drill bit and the notch on the tip of the bit and it provided enough surface to move the bolt and spin it out. I broke the bolt using an impact wrench to get the bolt off that was on way too tight. I couldn't get it off by hand or with my 18V drill. But the impact wrench losened it up. Jut a little to strong I guess. I should have stoppped as soon as I got it to budge. I'll order the replacement bolt.

Guess I'll have to wait to try the new blade. Too bad I was anxious to check it out.

Thanks all.

Don't over tighten your arbour bolts. "Snug and a bit" (with a hand wrench, NOT a power tool) is more than enough. For the reasons outlined by Mr. Henderson above, these bolts will "self - tighten".

Happy to read that you got the sheared bolt out - just don't over tighten them in the future.

Bruce Barker
07-04-2008, 1:29 AM
Slightly OT, but recently I changed blades on my miter saw, and "snugged" it (not "snug and a bit" as recommended above) since I am paranoid of breaking bolts.

The new blade, a Freud, completely changed the sound of the saw. Was the strangest sounding thing. Would whistle as it started much more slowly than before, then would sing as the blade spun down more slowly than before. I was thinking, how could a blade make the saw sound and run so differently!

I bet you have guessed what I did wrong by now...

Steven DeMars
07-04-2008, 2:39 AM
Steven was right. I used a metal drill bit and the notch on the tip of the bit and it provided enough surface to move the bolt and spin it out. I broke the bolt using an impact wrench to get the bolt off that was on way too tight. I couldn't get it off by hand or with my 18V drill. But the impact wrench losened it up. Jut a little to strong I guess. I should have stoppped as soon as I got it to budge. I'll order the replacement bolt.

Guess I'll have to wait to try the new blade. Too bad I was anxious to check it out.

Thanks all.

I keep some left handed drill bits to do the same for right handed bolts.

Johnny Pearce
07-04-2008, 9:54 AM
Backwards rotation ?????

Bruce Barker
07-04-2008, 11:19 AM
No, but just as dumb. Didn't tighten the arbor bolt enough. The blade was freely spinning on the bolt. Rather sobering when you consider what would have taken place if the bolt had fallen out. Thank goodness they are reverse threaded.

Steve Clardy
07-04-2008, 11:34 AM
I keep some left handed drill bits to do the same for right handed bolts.


Yep. I have a set also. Sure are handy at times.


No, but just as dumb. Didn't tighten the arbor bolt enough. The blade was freely spinning on the bolt. Rather sobering when you consider what would have taken place if the bolt had fallen out. Thank goodness they are reverse threaded.


Oops. :D

Gene O. Carpenter
07-04-2008, 2:46 PM
The action of the threads binding against one another, DUE to the bolt head/flange coming in contact with the flange washer, is what secures that blade firmly to the shaft. Some have a type of Thrust Washer to apply holding grip to the blade and still allow slippage in case of a serious bind. When the blade and the locking washer are in position the end of the saw mandrel is ever so slightly below their outer edge, to give "take up room"!
If you turn it in the wrong direction you're creating a strain on the bolt head and quite naturally applying too much strain the head will snap off! Now the "binding action" is no more! So the bolt remnant should turn easily out..Just have to turn in the right direction!
If you try to drill or tap it out by any means you could possibly mess the shafts threads up or even swedge the bolt in tighter..Been there done that! I was into motors and mechanics before I got into amateurish woodworking..Those years of mechanicing have helped me tremendously with my WW machinery.

The easiest way would be If you have a Dremel or other rotary tool, use one of those "fine" grinding cut off wheels put on a pair of safety glasses and very carefully cut yourself a slot in the bolt. If it broke off flush you should still be able to get a deep enough slot to get a bite with a screwdriver but even if the end is slightly below the shaft's end go ahead and cut a little deeper..AGAIN, determine the correct removal direction and using a smaller screw driver turn it out. The 2 little slots will have no effect on the saw's operation..

Just remember, "if the blade is on the Right side of the saw the Arbor Bolt will be a Left hand thread and if the blade is on the Left side it will be a Right hand thread"..

Zack Monroe
07-15-2023, 8:20 PM
I'm in a similar situation with the same model saw. But the bolt head didn't shear off, it's still attached. It spins but doesn't come off.

Any thoughts appreciated.

Bill Dufour
07-15-2023, 9:44 PM
5/58 bolt torque is recommended about 120-180 foot pounds for max shear. I would say that is as tight as it is safe to go before thread failure. I would not go over 50% of those numbers on a bolt that should come out at some time.
For myself about double spark plug torque should be enough. Oil filter torque would be about right.
Torque is not transmitted through the bolt. It is friction between the arbor flange and the blade that transmits the torque. The bolt just keeps things aligned and touching so they do not slip.
Bill D.

Zack Monroe
07-15-2023, 10:40 PM
Bill, thanks for the quick reply but I'm confused.

The bolt was overtightened while turning it CCW to take it out. Left hand thread was unknown at the time.

Something snapped but the bolt is still attached somewhere and does not pull out.

I suppose I can grind off the head, remove the blade and see what's going on underneath.

Jerry Bruette
07-15-2023, 11:26 PM
Sounds like you may have stripped the threads. You've either pulled them off the bolt or out of the arbor and they're still bound up together. For your convenience I hope the bolt is stripped.

Lamar Keeney
07-21-2023, 10:29 AM
My Dewalt miter saw has a left handed bolt.

Rod Sheridan
07-21-2023, 3:27 PM
Drill, tap and insert a NORMAL bolt. It's left handed, no easy-out needed.

I certainly wouldn’t do that on a bolt that secures a saw blade, there’s a reason the manufacturer put a left hand bolt in.

Regards, Rod

Steve Clardy
07-21-2023, 4:50 PM
I certainly wouldn’t do that on a bolt that secures a saw blade, there’s a reason the manufacturer put a left hand bolt in.

Regards, Rod

Agree. Not a good idea.

Dave Zellers
07-21-2023, 10:06 PM
This is a misunderstanding. He was talking about tapping threads inside the broken bolt to aid in removing it, not changing the thread rotation of the arbor itself.