Which is better, the nail or the screw?

[aerontg]

I'm wanting to get into some carpentry projects, would like to know which is better to use: nails or screws? Besides that, I'm going bonkers over trying to figure out why my circular saw won't cut to measurement. Do I need a table saw instead? The two projects I want to do are a trash can shed (to keep the dogs out of the cans and water from filling mucking up the area) and a chicken coop.

[bee_pipes]

Mind you, I'm no carpenter, but I have had a little experience. Nails are faster for construction - you drive a nail and move on. Nails are generally cheaper too.

We have hard wood that we mill ourselves, so we have had to use screws on many construction projects. After bending a hand full of nails without driving a single one through the board, I switched to screws. That requires a drill for pilot holes and a good screwdriver. My smart wife got me a makita last christmas and it is a wonderful tool - much better than those underpowered black-n-decker screwdrivers. If we use store bought lumber, nails are my choice because the job goes so much faster.

It takes more gear for working with screws - drill, bits, screwdriver, etc. and costs more, but does a better job for dealing with warpage, etc for stuff exposed to the weather. Nails make a faster job of it, and maybe an experienced fellow could get the same results I need screws for.

Regards,
Pat

[rAcErRicK]

Yea, the screw v/s nails is a quandry. I tend to use screws because they seem to hold better, plus I do not like blue thumbnails ! Drilling a hole in them to let the high pressure blood out somehow tends to ruin my day.
But I can remember my Grandfather (old school carpenter) trying to teach me the "art" of driving a nail. He would carefully study each peice of wood as if it had it's own personality, and drive the nails accordingly, at carefully and properly angled and placed nails. If he thought a board would tend to warp, he could nail it so you could not possibly tear it off. Each joint had it's own specific nailing patern. A science maybe, Some of it "took" and some did not, but the "art", and his knowlege of it, is a pleasant memory.

I've noticed that most folks just think a nail in a joint, is just a nail in a joint. The real difference is the "nail art". You either got it, or you don't. I think this is probably the biggest difference between the two, as far as holding power, splitting, and so on. I've seen him strike the point of a nail to blunt it, if he suspected the board might split, the blunt seems to tear a hole while going through, rather than a wedge effect, which tends to split the wood. The memories always bring a smile, and I always ask myself, now, how would Pa do this ?

[Shamrock1121]

I'd take the time to drill pilot holes and use the correct type and size of screw FOR the job. It will last longer and you'll get more stability and less potential for spliting the wood than driving a nail. If you use a nail I'd also suggest you glue the joint and clamp it.

- (handy-gal) Karen

[MooseToo]

there are those who nail very hard woods by also using a pilot hole - plus, $50 worth of nails will build a lot bigger thingie than $50 worth of screws -

[tufhelp]

True, but if you need to make a "correction" in your effort, screws sure come out easier and allow for a lot more finagling... Especially v.s. nail guns, where you tend to over nail, then you have a real problem for a correction...

[tufhelp]

Improving your circular saw's accuracy is relatively easy with a couple of shop made jigs know as cutting guides.

These plans are for long or rip cutting guides, you can also make a shorter version for cross cuts:

http://wayneofthewoods.com/circular-saw-cutting-guide.html

This circular saw cutting guide is so easy to make and so easy and accurate to use, you will be kicking yourself for not thinking of doing this sooner!

http://wayneofthewoods.com/circul3.jpg



Step 1 - Obtain a 12-inch wide (or as needed) piece of plywood (1/4" to 1/2" ) that is the desired length of the type of cuts you will make. If you are ripping 8-foot plywood, then make the guide 8-feet long. You may wish to construct several guides of different lengths.


http://wayneofthewoods.com/sawguide1.GIF



Step 2 - Obtain another 2-inch wide board or strip of plywood that is thin enough so that when your circular saw rests up against it the body of the saw will clear over it. This board will be the guide. Fasten the strip onto the plywood so that the blade is about 1 inch in from the edge when the saw rests up against this guide board.


http://wayneofthewoods.com/sawguide2.GIF


Step 3 - Rip down your plywood with the saw resting against the guide board.


http://wayneofthewoods.com/sawguide3a.GIF


To use your guide, simply draw a line on the board you are cutting. Clamp the guide on with the edge of the guide lined up with the drawn line. By default, your cut will match the line since the saw will always cut flush with the edge. Make sure to use the same type replacement blade since different blades have slightly different cuts. No measuring to place the guide, just to draw the line and clamp!


Crosscut version:


http://i134.photobucket.com/albums/q82/willyallen/CCSAWSLED-1.jpg


Just as above, make the base for the saws plate a little bigger and then cut the extra off giving you measurment "A"

[chrisser]

The nail vs screw question, to me, comes down to the application.

For something like a corner joint where two pieces of wood come together and there is nothing supporting the joint, then I view nails as simply a permanent clamp to hold the wood together, and use glue.

But if you really don't want it to come apart, then screws can't be beat, and screws and glue is about as close as you can get to perfect without joinery.


Now, for framing a house, where in a lot of cases gravity is holding things together and the fasteners are basically keeping things from moving around until you get the sheathing up, nails are fine.


Other thing to consider is the forces acting on the pieces. If the expected force is going to be pushing the piece with the nails away from the other, then nails aren't going to hold and screws are a way better option. Example of this would be floor boards on a wood deck - eventually the nails are going to pop out as the wood moves around and a screw would be a better option.

When the forces are perpendicular to the fastener, then nails do OK and sometimes a large diameter nail is cheaper than a screw with equivalent shear strength.


I have found, though, that in most cases, its worth spending the extra time and money on screws and glue or, better, decent joinery and glue. Depends on the application, but even if nails hold, you still have to worry about squeaks, wood twisting, etc. I like to do the job once and have it last for years so spending a little bit more up front is worth it for me. I have too much to do to do the same jobs twice. I've also lately been using a lot of construction adhesive, along with nails or screws, for even routine house jobs. Takes care of any squeaking and makes everything more rigid. Gotta make sure everything is accurate though because once its all bonded, its permanent.


Regarding the circular saw, I find that a table saw or power miter saw is always easier to use with accuracy. However, circular saws are a better option for cutting things like plywood sheets where its far too difficult to feed something that large through a table saw. You can make jigs to address that, but they end up taking a lot of materials. I do something similar to the circular saw jig above, but I just use an eight-foot aluminum level that I picked up pretty inexpensively from Lowe's or Home Depot. Its exactly as long as 4 x 8 sheet. Takes some careful measuring, but as long as the sheet you're cutting is supported along the cut length (if it bows, your saw guide can slip under the level guid), you just clamp the rigid level on both ends, set the saw against it, and get a nice accurate cut.


Above is just my experience. As they say, your mileage may vary.

[knucklehead]

chrisser said something I think needs to emphasized. Generally nails are tough and screws are brittle - try to bend a screw in half. Screws are designed for use in tension or where forces will be along the length of the screw. Nails are used where shear forces are found; that word pretty much defines itself as the forces would tend to shear the nail in half.

You can get in trouble if you use screws in a shear situation and they are not tough enough. However, building a garden cart or small shed is different than putting rafters on your home. I believe there are construction screws available that are tough but I have never used them.

Understanding for what use your fasteners are intended is important.

[knucklehead]

tufhelp's post might lead to me changing the way I do things, but here's what I do when sawing panels:

First a good thing to remember: All saws should do the cutting and not be pushed through the cut too strongly; use a firm grip but lighter pressure on the saw.

I find a straightedge or thin piece of straight wood (1x4 or 1x6) and clamp it on the panel with a couple of those large spring clamps

http://www.aircraftspruce.com/catalog/graphics/83-262.jpg

Then I measure the distance across the platen or base of the saw to the blade (best done unplugged) and set the straightedge that far from the line. You have to remember to add a little more for the blade thickness if the piece you are cutting free is the one you want as opposed to piece on which you clamped the straightedge.

If you set up on a piece with your straightedge, clamps, and saw and look things over, it will become clear. You could even write what the measurements are on the top side of the platen.

[HockeyFan]

I generally shy away from a "one size fits all" mentality. The reality, as I see it, is that nails will be better for some work, and screws will be better for others.
Consider that a good screw gun can be a life saver. A good nail gun can be a life saver.

Consider that nails pull out with expansion and contraction a little more than screws do. I tend to prefer screws, but I've used nails to, depending upon the job.
What I tend to do though, is make sure that the screws I use are the cheapo ones you buy from Home Depot or Lowes. I tend to head down to the Fastenal store or the Hilti store and buy the stuff that builders use. The screws from Lowe's often break off when being put into hard wood. And as far as I'm concerned, they're not inexpensive. Lowe's and Home Depot and those places tend to sell in quantities of 25 or 50 at a time, and they charge way more than they're worth. Buying from the builder stores (like Fastenal) tend to get more for the money, and you get a better product too.

I can't comment too much on nail guns, because I've only had mine for a limited time and haven't used it much (yet). I'm planning to use it for finish work inside the house. Most of my framing will be with screws, as a lot of the framing will be with metal studs, rather than wood. I can carry this stuff a lot easier than wood, and it doesn't warp (not to mention that the termites wont eat the stuff).

In summary, I'll repeat that I use both screws and nails, and shy away from suggesting that one is better than the other. You know what you're tasks are and how you work, and that dictates what you should use more than what other people tell you (in my opinion).

[JAK]

There is an old boatbuilder saying...

Nail it.
If a nail won't hold, screw it.
If a screw won't hold, bolt it.

Of course there are non-metalic options, like pegs and such...
They usually require considerably more skill.

[flatwater]

I have always figured that a good screw beats getting nailed any day ;D :D :-*.
Flatwater

[High_Desert]

A friend of mine worked in a private wood testing lab here in the Northwest. They did all different types of testing from exposure to strength. One of the interesting things he passed on to me is that a screw driven in with a hammer had better holding strength than a screw driven with a driver. It had to do with the way the wood fibers shredded and regrouped under the threads. It may not be practical, but I thought it was interesting.

HD

[Av8rTx]

Regarding accurate cuts: this may seem so obvious to be considered insulting, at isn't meant to be. I recently had to educate a Home Depot employee who I had make several cuts for me from a large sheet of ply wood that they had to eat about this; Blade thickness! have the edge of the blade sitting on the waste side of the cut, if not it will be approximately 1/8" short. If you are making a series of cuts like that the cumulative effect can be pretty dramatic.