Snapping of screw heads

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Just when I think I have a little momentum...
For background, I'm building a bookcase with butt joints (no fancier, stronger joints for this first project). So to reinforce the butts, I decided to use wood screws to help secure things. I am drilling a 3/8" forstener (that I will later plug), #8 countersink pilot, followed by further piloting through the boards with a 3/32" (I think).
Well, I've just snapped off two tops of the screws going into the holes. I even tried running the threads along a candle on the second one (tip I read here). So what is my problem - not a wide enough pilot hole? What size bit should I use for a #8 wood screw?
Thanks
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It is not your holes, probably your screws. If you are snapping screw heads when screwing #8's into a 3/32" hole you need to learn a new lesson. Quit using they style screw you are using and move up to a woodworking screw. Take a look here, http://www.mcfeelys.com/subcat.asp?subcat .1.5.1.2. And if you are still using Phillips head screws that will be a good tome to switch to Square head screws. Most of the screws sold at McFeelys are square drive.
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Well, I am using wood screws vs. a woodworking screw (name on the package). And they are phillips.
I know the experts will cringe. But as a beginner, my sources for now will come from Lowes/Menards. I'm not ready to move up to specialized ordering yet. And I don't recall seeing a special woodworking screw at Lowes.
Any other tips for now besides changing screws? Should I try increasing the pilot hole to 1/8"? Or maybe my pilot hole wasn't deep enough?
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Did you get the screws in a small package and at the local Borg? McFeeleys screw are hardened and seldom break. Yes you are ready to move into specilized ordering... LOL. You broke 2 screws already right? McFeeleys screws are probably cheaper than what you are buying now. Typically you can get 100 screws for about $4-$6. $ to 6 cents each. I pet you paid more than that for the ones you are using now.
Your pilot hole should be the size of the screw sidth less the threads. You really should change screws. If you go to McFeeleys, you will wonder how you got along with out them. They will not let you down.

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With a good screw, the pilot hole and size are OK. The big stores carry cheap screws. In spite of your comment, you are ready for better quality. No, you NEED better quality or you will frustrate yourself to no end. Go to McFeelys, or get Spax screws from Lee Valley.
Also, pay close attention to how you are driving them. Too fast or too much torque on a drill will cause a snap. You want a nice even pressure and medium speed. If you are using a drill with a clutch, be sure to set it properly. If you are screwing in with a corded drill, use caution. If you are driving by hand, just don't go so damned tight.
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In all honesty, they're probably really cheap screws. You don't have to go to specialized ordering, just source out some better quality screws. You've already had some suggestions from others here. And yes, I highly recommend square drive screws ~ easier to drive in, much easier to control. They're called Robertson up here in Canada. Not sure if they have a specialized name in the US.
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<snip>

Corey, Leon gives you good advice, although you'll have to wait for the McFeeley's order to arrive in the mail.
Jim has one of the great deals in woodworking for the beginner. $10 gets you a wide assortment of the types of screws woodworkers use, plus his catalog. It may even come with a coupon, for reordering. I don't remember. But the quality of the product, and the quality of the assortment makes it really worth the $10. Jim doesn't likely make a bunch of money on these - probably loses some. But he makes a bunch of converts.
If you can't wait, then put a couple of the screws you've been using in your pocket, and go find a hardware store that says something like True Value, or Ace, or Do It Best on the side, along with an owner's name. Go find someone who looks like they remember the 50's, and ask them for some screws like these, only not made of cheap crap. While you're there, find some furniture or flooring paste wax (Johnson's, TreWax, Butcher's or similar) Not only will you use it for screw lubrication, but it's a good last step in the finishing process for your project.
Congratulations on getting this far in the learning process. Solving these problems is just part of the fun, and one reason we hang out here.
Patriarch
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Much as you don't like the answer, Leon is correct -- the screws you are using are the problem. You *might* be able to use Borg-supplied screws if you do not seat them very tight (kind of defeats the purpose though). I found that I could not use screws supplied from Home Depot for any purpose without the heads snapping. I think they are able to get away with this because most people purchasing the screws are drilling them into the soft, wet, white wood that the Borg also sells. They definitely won't work in hardwood *at all* -- DAMHIKT. You are only going to cause yourself much more work all for the sake of saving a couple of dollars.

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Lubricating your screws with a little parrafin or just having a bar of soap handy to rub on your threads before driving them may help .
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While Soap works, it is a poor choice for long term effects on the screw. Sop generally has lots of moisture and will cause the screw to prematurely rust.

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Agree with Leon, use McFeelys square drive screws and most of your problems with screws will be gone. However, regardless of the screws you are using and the wood involved if you proceed as follows you will avoid trouble: 1. Use scraps of the wood involved to first try out drill sizes...same principle as using scraps to try out a new finishing technique...if you don't first use scraps them your project boards become an experiment. 2. First determine the hole size needed in the first board so the unthreaded portion of the screw will go in with little or no force required. You need a set of drill bits between 1/16 and 1/4 that increase in size by 1/64 increments. Just keep using larger bits until you get the right sized hole. 3. Next determine the size of hole needed in the second board. Start with a bit about 3/32 smaller than the bit you ended up with in step 2. Try to screw one of your screws into this hole using a hand driver so you can feel the amount of torque required. If it is too tight try the next size larger bit, if too loose try the next size smaller. 4. Once you have the bit sizes, if you intend to drive the screws with a power driver you need to practice screwing two pieces of scrap together and get your clutch adjusted so it just barely drives the screws home. If your power driver does not have a clutch then be sure to stop before the screw bottoms out. Even with a clutch I like to use a hand driver on that last turn or two so I can feel when they are tight. Earl Creel

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wrote:

on scrap of the wood your project is made of.. gotta remember that one!
What Earl's post reminded me of is that buying a $5 drill index really helped me in choosing/sizing drills/dowels, etc... for example, using Earls' advice, try different screws & drill sizes... but also run your screw through the drill index and see what "drill size" the shank is...
I just had to do that with my plug project.. I had the plugs cut but wasn't sure what hole size they plugged... lol I used the drill index to find that the "small" end of the plug was 21/64, and drilled my holes to that size.. YMMV
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What kind of wood? What is the country of origin of the screws? #8 might be a bit small.

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Red Oak for the wood.
No idea on the country origin of the screws. Someone recommended 1.5" #8s a while back for 3/4" red oak when I was first inquiring about what screws to use.
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#8 is fine for furniture. Generally speaking you want the screw to be 3 times in length as the thickness of the material that you are attaching.
3/4" would normally need a 2.25" long screw.
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ranted:

Oak is quite hard, especially on brass screws. Wood screws have a tapered shank and threaded area, so you need a tapered bit.
Find the proper #8 wood screw boring bit and use that. They're tapered and many also have a countersink/bore built in.
One example is this set www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumberv08
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Corey,
In my opinion you should invest in a good countersink set for wood screws like Fuller. I had the same problem until I bought my set. Works like a dream with any type of wood screw from any source. For #6, #8, #10, and #12.
Philly

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Are you using coarse thread screws? Red Oak is hard and should be screwed with fine thread screws. The coarse threads are for softer material. -dave

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I suspect that you don't have a large enough clearance hole in the first board. You should be able to drop the screw through the first board to rest in the countersink with no tools.
Are you using the old tapered wood screws? In very hard woods, they require a tapered lead hole.
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that I think that one can get decent screws at the local hardware store and even at a Borg.
Fasterner quality, substandard products, and counterfeiting is something I know something about. Commercial and military airplanes have crashed because of bad quality fasteners -- and those buyers are supposedly on top of things and willing to pay. The Borgs may have fastener standards for the buyers and this time a bad shipment came through. Maybe they have no quality standards. Don't know.
IME, I've had my biggest quality problems with lag bolts over the years. But I have very rarely had a problem with screws heads snapping -- screws I bought at local hardware store or a Borg. Now head stripping, as well as but stripping -- phillips and square -- is another matter, and that also is a quality issue.
Depending on your time and level of interest, I'd suggest you tell the place you bought the screws that they got a bad batch and ask for a refund. I'd get new screws at the local hardware store for now -- with due, honest respect for McFeeleys.
As for coarse versus fine threads and proper hole size and shape, I defer to others here.
YMMV. -- Igor
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