Non-corrosive wood screws

[doe4rae]

I want to add some screws to my outwales and CanoeCraft says to use #8 1 1/4" non-corrosive wood screws. I will countersink and plug so they won't show. This is probably a really stupid question, but is this a specialized screw? I am looking at the screws online at Jamestown Distributors for example and they say "Choose from non-corrosive marine grade Stainless Steel, Silicon Bronze, Brass, Galvanized." I can get stainless steel wood screws right here in town. The reason I'm second guessing myself is I don't know if they are "marine grade" and they don't say "non-corrosive" on them anywhere. The guy at Ace assures me they are but I don't trust him. I already bought one box of screws from a guy at Menards that I can't use. I specifically said " #8 1 1/4" NON-CORROSIVE wood screws." I told him I was using them on a boat and they would be exposed to water even though I'm pretty sure they will be sealed away from the water for the most part. When I got home I looked at the box again and it says "not for use where surface rust or staining may be a problem." This guy obviously didn't take me seriously.

Can I use the stainless steel screws from Ace Hardware or do I need to order them online from a marine supply dealer?

[willo]

Use the stainless from ace , they will be fine, I get screws from the local hardware all the time. There is no need to get anything specified as for marine use. Generally stainless and brass make good choices, but I use brass only for screwws that are left exposed.

[Rod Tait]

If you ever think that you might need to take a screw out even if it is countersunk and plugged, I would go with silicone bronze. It will come out 40 years from now. Brass is too soft and will likely break off the head if tightening too tight.

[BWB]

Use stainless, especially if they won't show. The alloys commonly used are almost completely passive (will not corrode in any normal conditions), and are considerably stronger than either brass or bronze. The only compelling reason to use brass or bronze would be for cosmetic considerations. With any of them I'd be sure to get my clearance holes correct, and with yellow metal use an identical steel screw in the hole first, then remove it and seat your brass or bronze. This might be overkill with short lengths in very soft wood, but..............

[doe4rae]

I can't believe how complicated buying a box of screws is! Before lunch I had asked a guy about the stainless steel screws at Ace. He pulled some out of a drawer and told me they were the right ones for my project. Skeptical, I came back here and posed my question and looked at some other places online. After lunch I went back to Ace to get those stainless steel screws and there was a different guy working. Had to go through the whole story again. I showed him the screws that the first guy showed me and he said "no those are for metal or steel" (STILL THE WRONG SCREWS) and he hooked me up with a completely different kind of screw. This time not from a drawer (I like being able to read the descriptions on the box) and it was definately "non corrosive". I was worried the "star shaped" head on them was going to be an issue but there was a special drill bit in the box for them too. Any wonder at my lack of trust with hardware employees when I go in three different times and I am given three different kinds of screws?

I had ordered a #8 fuller bit from Merton's when I ordered the silicon bronze carriage bolts so I played around with the new screws and the fuller bit in a 3/4" piece of scrap maple (I have a lot since ruining my first set of inwales.) I got the depth set right to sink the screw head 1/4" into the outwale and the screws grab about 1/2" into the inwale. With the bevel on the outwale, the hole that the Fuller bit made was right at the edges... maybe a little too big but I think after I plug the holes and sand/plane it down a little it will look just right.
Thanks again for the advice.

[BWB]

I would caution you to verify that the screws you got are actually stainless steel. "Non corrosive" is a very imprecise term that could be applied to just about anything with some sort of coating on it. If they are indeed stainless steel the box will say so. If it doesn't, they probably aren't, and you could be disappointed over the long term.
I suggest you look over a Leigh Valley catalog or their website (or other internet sources) for good information on fasteners, and the differences between wood screws and other types, regardless of material. Lots of good info out there, and it's an important part of the journey.

[Denis]

I was advised last year on a project that most stainless screws were intended for sheet metal work which is why they are threaded to the head as opposed to wood screws which have a partially smooth shank.

Where I ran into trouble was not sizing the hole properly and I had several screw heads break off just as I was seating the screw. Not going to happen this year lol

Your project is coming along nicely, Very good work



Denis

[doe4rae]

Thanks BWB... I will double check that before I plug the screw holes. I am almost positive that they are stainless steel. The first box I got were wood screws and the thread and shank were entirely different than the second screw I was given (stainless steel but for metal.) That one was as Denis described; the threads were all the way to the head. Not only that, but compared to the first screw it had a thicker shank and tighter and finer threads. Both were #8 1 1/4" screws but they were NOT the same size. I had both in my hand and told the hardware guy they were not the same size. He insisted they were, but when he took them both and put them through the little plastic template they have that says what size your screws are, his #8 fit snugly and the #8 I got from Menards was very loose. I showed him the difference in threads and the shank size and he then directed me to the screws that I purchased which were specifically for wood. Very different thread and finer shank with -- how do I describe it -- kind of a sprial groove around the shank of the screw (not the threads).
Anyway. I hope they are right because I am tired of fussing over screws. :rolling eyes

[Rod Tait]

I find differences between different suppliers as well, depending on whether it is north american or off shore. The other thing is whether the thread is a cut thread (cut onto the stock) or a twist thread (twisted rod to create a thread). I find cut threads to be better. That is why I always go with bronze s stated earlier. If your screw corrodes even a little, you will get black marks and eventually the wood will rot around the hole. You have no idea of how many screws I have pulled on repairs in which the so called "stainless" was pretty much gone inside the wood.

[doe4rae]

I want to be able to sleep at night, so I went ahead and ordered the silicon bronze screws from Jamestown Distributors. I hope there will not be an issue with removing the stainless I already put in (as far as how the threads already cut the wood) and re-inserting the sb screws. I had to buy lubricant for the screws and a frearson driver bit too. If this keeps up I'll have so many nickles and dimes into screws and bits that it will end up costing as much as the lumber for the boat!

http://www.jamestowndistributors.com/us ... +Flat+Head

[Denis]

If you can get a steel screw similar to the ones you are buying insert it first then back it out and insert the silicon bronze screw if you are concerned with them breaking.

Denis

[WiJerry]

I built my stripper about 10 years ago and used Silicon Bronze screws for the gunnels and silicon bronze bolts and washers and nuts for attaching the seats and thwarts. They went in fine and have held up well. They came from Jamestown. I like silicon bronze much better than the brass or stainless steel screws I have used for making other boats.