Drill size for wood screws?

[chopperusa]

I know this is a dumb newbe queation but if i measure the small diamater of the wood screw threads. And i am refering to the minor diamater or the bottom of the threads , do i drill the hole to size or approxamatly 2/3 of this dia.
I am asking this because i am having some problems with the soft maple stripping out. I have used some thin super glue (CA) to harden the wood after threading into the stock and this helps some. While i am on the subject of wood screws i am having some difficulties finding really good high quallity machined non-plated gun screws. Did have some and order replacements from severall suppliers but their just not as well made as i prefer. I may be a little to picky but too many of the wood screws vary wildly on their sizes.

 

[Stumpkiller]

If you drill slightly under the shank diameter for the threadless area and about 1/3 that for the remainder you should be OK. When in doubt, hold the bit and screw up to the light and choose a bit that is the size of the screw at the bottoms of the thread grooves.

Several companies make tapered bits for wood screws. I've had good luck with these. I believe I got mine from Jamestown Distributors.

I get all my unplated wood screws from Brownells of Utah.

 

[GobblerKnob]

You may also try a drill bit gauge. It's a metal plate with holes bored to the exact diameter of the bit. Find the hole your screw fits into then use the next size smaller (or two) drill bit. Once you figure out the best bit for the screw you have, keep a note of it for future reference. This method works well for me. I bought my gauge at Lowe's. Rick

 

[paulvallandigham]

Anytime I am working on putting wood screws in a gun stock, I recommend drilling a pilot hole for the screw with as small as drill bit as you can buy. 1/32" is not too small. Gunstocks are usually made of hardwoods, and that indicates that they do not accept nails, or screws willingly. The last thing a builder wants to happen after spending hours making a gunstock is to see cracks or splits form when he is driving in a screw. A pilot hole will stop that.

However, you do want to use a properly sized drill at least as wide as the shank of the screw, but less than the total diameter of the threaded portion of the screw to make a properly sized hole for the screw. Just be sure to stop the drill short of the bottom of your hole about 1/8" minimum, to leave allowance for the tapered threads at the point of the screw to do some work.

Blow out the chips and dust, and then rub the screw's threads on a bar of soap, or block of wax before running them down into the wood. The soap will lube the threads, and protect the wood where the threads cut it. The soap will also make it easier to remove the screw, and will help hold the wood fibers of the wood that are cut by the thread apart to make it easier to reinsert the screw without cutting new wood. Cutting new wood is the way that screw hole ultimate destroy the wood, and the wood will no longer hold the screw.

 

[DickS]

You can also cut some little notches into the leading edge of the screw's thread, so that the screw tends to cut its way in, like a tap.

 

[chopperusa]

I thank you for your coments. I didnt even realize that there was tapered drills made for wood screws, so that will be a next purchase. I have also been drilling slightly under the minor diamater of the threads thinking this might compress the wood fibers slightly to help make a tighter fit. Will pay more attention to not drill to deep so as to allow the screw point to do more work. The soap does work well as i have been doing that allready. Does any body know of a large woodworking company that might stock the really NICE wood screws, so i can buy in bulk (100-200) screws at a time to maintain some consistency in the screw fits.

 

[paulvallandigham]

Ask at the Commercial desk at your local Ace True Value Hardware store, or home depot, or Lowes, etc. They order such things in bulk for the contractors they serve.

 

[GobblerKnob]

visit[url] www.kennedyhardware.com[/url]. They sell unplated wood screws in large amounts. I don't think you'll find unplated screws at Lowe's or Home Depot. Rick

 

[chopperusa]

I think i might just try some of their scews, and i noticed they stock small cut nails that might come in handy!

 

[Jim-Iowa]

I once picked up a set of Vermont America screw bits at Menards at a very low price.
They looked like spade bits in a screw profile that had been stamped from sheetmetal with the shank bent round to fit the drill chuck.
I did not have great expectations.
But have been using them for 15yrs now and would buy them again if I needed them. :shocked2:

 

[Bon Sauvage]

I think that I would go with beeswax on the screw threads rather then soap. My old woodshop teacher always used to say that the lye in the soap would have long term destructive effects on the screws.


Ogre