Stripped screw head - Help

I've got a Table Saw that need some maintenance, problem is I can't get the screws out. There are four steel phillips screws holding the aluminum arbor guide. I managed to get two of the four screws out by doing some serious pushing while turning. The two screws that came out made a popping sound when they broke free. The other two heads started to strip, so I left them until I could find a better solution. I managed to get one more screw out with an impact screwdriver. The fourth screw is pretty much a round hole now and will not budge. I can't get vice grips on this screw, as the head is recessed.

Should I try heat next, a left hand taper or carefully expoxy something to the screw head? I understand the screw outs are pretty much useless on a tight screw. Suggestions appreciated.

Reply to
Bill Stock
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(my first post here)

You could grind the top flat, then carefully file a deep slot in it, and try to turn it with an appropriately sized flat blade screwdriver. I've done this a few times with sheared bolts in cars. Heat might help break it loose, too, as may tapping around it with a mallet.

Consider not replacing it with a new phillips head screw; perhaps something less trouble-prone, such as capscrews?

Cheers,

j.

Reply to
indigoid

(Snip)

Got a welder?

Set the wayback machine to the left upper coast of the U.S. on October the fifth in the year 2000, at about seventeen minutes before noon, Sherman:

From: Glen ( snipped-for-privacy@spamdeleteoregoncoast.com) Subject: Re: How to remove stuck exhaust header bolt? View: Complete Thread (9 articles) Original Format Newsgroups: rec.crafts.metalworking Date: 2000-10-05 11:43:02 PST

One standard technique here is welding a nut on the stud so the nut is down on the casting, while it's cooling squirt WD 40 or Croil on it, rap it with a hammer while it's cooling if it looks really bad, then with axial torque (no one sided pressure) turn it out. That works well for us and has for many years. We use a MIG welder for that, I'm not sure I'd try it with a stick welder. I call easy-outs "hard-outs" because after the thing breaks off in the hole you have even more of a challenge, and they almost never work as advertised in my experience. A torch can be used to anneal the hard-out (they come into my shop complete with broken off hard-outs) and then the hard-out is drilled out, then one or two drill sizes under tap size, and pick the left over thread pieces out, sometimes tap them out. If a stud or screw is broken off flush or a bit below we build up a weld "spire" to weld the oversize nut to, set the nut over the spire and weld up good, spray WD, cool and remove Anyone who brings a part in with a broken off hard-out in the hole gets a free lecture. Glen

--Winston

Reply to
Winston

Measure the diameter of the other screws. Find a drill bit that is the Minor diameter of the screw (look in the book).

Carefuly drill down the center of the screw..which is simple with a phillips head, all the way through the screw. Fish out any bits of metal that are left over. Clean up the hole with a proper size tap.

If you can find a Left Handed drill bit, its even better as it is likely to unscrew the screw after a certain point.

I had to do exactly this on the recessed blade guard "oval" on my old Wards cast iron 10" table saw. Took all of about 3 minutes with a drill motor.

Gunner

Insert new screw. "In my humble opinion, the petty carping levied against Bush by the Democrats proves again, it is better to have your eye plucked out by an eagle than to be nibbled to death by ducks." - Norman Liebmann

Reply to
Gunner

Chances are if you drill down into the stripped Phillips head, the head will fall off, allowing you to disassemble the arbor guide, leaving the screw sticking up. With the tension relieved, it will probably unscrew easily. If it is more than finger tight, use vise grips, or saw in a slot.

Reply to
Leo Lichtman

You could try a centre punch on the circumference of the screw head, and tapping it with a hammer. That's worked for me on a few occasions.

Leon

Reply to
Leon Heller

"Bill Stock" wrote in news:JCN4d.1353$ snipped-for-privacy@news04.bloor.is.net.cable.rogers.com:

Amongst the wise answers and some not so wise for this particular situation, there is another alternative. Using an appropriate sized Torx bit. This method works for rounded out phillips heads, as well as smaller socket head cap screws. Just drive the Torx bit into the rounded out portion of the head. With torx, you have 8 straight contact points to help hold the screw. If you cannot get a bite, use a drill the minor diameter of the next size up Torx bit, and drill partially through the head, then drive in the torx bit.

Reply to
Anthony

With a Dremel tool and an abrasive cutting wheel, cut a nice square slot across the head of the screw. Use your best quality flat screwdriver to break the screw loose. Works for me 90% of the time.

Vaughn

Reply to
Vaughn

Before you try anything, use a good penetrating oil like Kroil. Let it soak overnight.

Reply to
Nick Hull

Gunner and I many have substantial political disagreements but we are of a single mind when it comes to the stuck fastener conundrum. This is the way to go. As mentioned elsewhere, because this is the last fastener holding it together, it will come adrift once you drill the head off. At this point a good pair of needlenose pliers might extract the remaining stub from the casting.

Jim

Reply to
jim rozen

Nick Hull wrote: tight screw. Suggestions appreciated.

I've done something similar with frozen nuts which were rounded off, or large nuts for which I didn't have a big enough wrench handy.

Use a flat chisel and a BFH to make an impression near one end of one of the flats, Then tilt the chisel and use it to drive the nut in the loosening direction. Reverse the procedure for tightening.

I actually learned this one from a 60s book which was titled something like "How to fix your own Volkswagen, a guide for the complete idiot." It was a precursor to todays "xxxx For Dummies" books. The author recommended using that hack technique to remove and replace some large nut (flywheel maybe?) instead of spending money on the right sized wrench.

Whatever woikes....

Jeff (Who believes that desperate times take desperate measures....)

Reply to
Jeff Wisnia

And before using that screwdriver take a couple of seconds to file across both sides of the tip of the blade with strokes at right angles to the shank.

That will put a "non-skid tread" of scratches in the right direction for them to dig into the aluminum and help prevent the blade from camming out of the slot.

A gunsmith tought me that one, and like my Uncle Schlomo used to say, "It might not help, but it couldn't hoit either."

HTH,

Jeff

Reply to
Jeff Wisnia

Kroil is truly amazing stuff. I heard all the hype for years, but didn't get around to buying a can until recently. I had to disassemble some rusted bolts a few weeks ago and tried the Kroil. After a few hours, I came back and they came apart so easy it was as if they had not been stuck.

Alan

Reply to
Alan Frisbie

Sears sells a set of extractors that are basically left-handed drills. You start drilling, and with an increase in pressure the bit snags and pops the screw loose. Sometimes, before the screw head is stripped out, I can get it loose by turning it tighter first, then loosen it. I don't know why this works. Perhaps the original tightening forms small barbs between the head and surface, all pointing in the direction of tight, and with a stuck thread it's too much? Tigtening further maybe loosens the threads and then the head friction can be managed. Just a theory...

Dan

Reply to
Dan Thomas

Alan Frisbie wrote in news: snipped-for-privacy@Flying-Disk.com:

There is a very good reason Kroil is stocked in the majority of your manufacturing plants.

Reply to
Anthony

Thanks for the advice guys. I finally got it out.

The original screw was a combo phillips/flat, so there was a partial groove left from the flat part of the slot. The screw was in a hole about 1/2" deep on one side and about a 1/4" on the other, so it was a bitch to get at. I heated it up with the propane torch and let it cool. Then tried to get some pressure on the remaining slot, without success. I was finally able to get a hefty center punch caught in the remaining slot and beat the hell out of it at a 45 degree angle. Once the head started to turn I was home free. I doubt the heat helped, but who knows.

Reply to
Bill Stock

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