Need 3/8" x 12" stainless screws/bolts

[Ljohnsaw]

So, my plans call for stainless screws (Edit: aka Lag Bolts) to hold down my cedar beams for my porch.  I see there are two types of stainless fasteners. Something called 18-8 (IIRC) and 316.  The 316 is twice the price so it must be better :  Anyhow, I will need between 21 and 28 of these things and I see the price is around $8 to $12 EACH.  I can get the price down if I buy 500. :D  Anyone have a favorite online hardware store that they can recommend? TIA  Looks like I might be needing them pretty soon! Yay!

[JohnW]

I think you have the size of it.  Based on my experience with one unusual nut and one strange bolt, there're a few outfits that can get you anything you want, but they're expensive

[Larry]

Why not hot dipped galvanized?

[Ljohnsaw]

Its what the engineer specified and its what is on the approved plans.  So I'm stuck with it.

[Walnut Beast]

The 316 has better corrosion resistance due to the molybdenum in it

[Ianab]

The 316 has better corrosion resistance due to the molybdenum in it

True, but even the cheaper ones will probably still be there after the cedar has rotted away. 
316 is for extreme exterior or marine use, where you expect it to be doused in salt water or spray regularly. 
304 is more general use. Food processing and architectural (interior and exterior) use. Probably what you want for this situation. 
Engineer is likely covering his butt because if the deck fails, it wont be his stainless bolts that rusted out. 
Try nailing up cedar weatherboards with stainless nails. If you drop one, you look for it.  :D

[Ed_K]

 Yrs ago I worked making spray nozzles. The 316 was used for corrosive liquid (like Ianab said) and 303 was for regular water type liquids. 304 for food use and 317 L for really acid type liquids. Maybe see if the 303 would work if the wood doesn't have acid quality's in it.

[Ljohnsaw]

Yrs ago I worked making spray nozzles. The 316 was used for corrosive liquid (like Ianab said) and 303 was for regular water type liquids. 304 for food use and 317 L for really acid type liquids. Maybe see if the 303 would work if the wood doesn't have acid quality's in it.

This is great info.  I learned something new today!  I just searched for 304 and I get "304/18-8" as the specifier of stainless type.  So I guess they are equivalent.  There is a big jump in price from 10" to 12" :-\

[1938farmall]

18-8 stainless hex head 3/8-16 thread, 12"lg $3.68 @ McMaster Carr

[sprucebunny]

BoltDepot. 3/8 x 12. 10 for $56

[Ljohnsaw]

BoltDepot. 3/8 x 12. 10 for $56

Stainless?  How did you get that price?  When I go to their website, I see single for $9.47, qty 25 for $217.03 and qty 250 for $2,036.  Your price is less than the 250 price!  Maybe they do a markup since I am in Cal$fornia :

EDIT:  I found them - those are "bolts" and I need "lag bolts" as in lag screws.  Bummer, thought you were on to a good find...

[Gary_C]

You can also find 304 SS threaded rod for $2-3 per foot.

[Ljohnsaw]

18-8 stainless hex head 3/8-16 thread, 12"lg $3.68 @ McMaster Carr

Thanks, but no - Sorry I wasn't clear in my OP.  I need lag bolts and McMaster only goes up to 10" on the 3/8" lags.  It looks like they would be in the $10 range if they had them.

[btulloh]

Sounds like Timberloks would be the appropriate fastener. Maybe bring that up with the engineer.  

[Ljohnsaw]

Yeah.  I sent him a message and hope to hear back early next week.  Even coated Timberloks are much less expensive.  I also asked if hot dipped could be used as those are pretty cheap as well.

[sprucebunny]

Sorry to get your hopes up, John. Guess I missed a word.

[Larry]

I also asked if hot dipped could be used as those are pretty cheap as well.

When I had a real job working for the phone company in the engineering department, our pole hardware was only designed to last 100 years.  All of our lag bolts were hot dipped and went into all manner of treated and cedar poles.  I never saw a pole attachment fail from corrosion or even come close. 

Having said that, I see your in California where there may be special conditions I don't understand, such as exposure to salt water.  Still, it sounds like an engineer being unreasonably cautious.  I might ask lots of questions or get a second opinion.

[scsmith42]

I also asked if hot dipped could be used as those are pretty cheap as well.

When I had a real job working for the phone company in the engineering department, our pole hardware was only designed to last 100 years.  All of our lag bolts were hot dipped and went into all manner of treated and cedar poles.  I never saw a pole attachment fail from corrosion or even come close.  

Having said that, I see your in California where there may be special conditions I don't understand, such as exposure to salt water.  Still, it sounds like an engineer being unreasonably cautious.  I might ask lots of questions or get a second opinion.

Larry, I'll bet that your company was sourcing hardware from A. B. Chance. They specialized in really high quality hardware for utility companies.

[scsmith42]

So, my plans call for stainless screws (Edit: aka Lag Bolts) to hold down my cedar beams for my porch.  I see there are two types of stainless fasteners. Something called 18-8 (IIRC) and 316.  The 316 is twice the price so it must be better :  Anyhow, I will need between 21 and 28 of these things and I see the price is around $8 to $12 EACH.  I can get the price down if I buy 500. :D  Anyone have a favorite online hardware store that they can recommend? TIA  Looks like I might be needing them pretty soon! Yay!

Around $8.10 each at wholesale bolt.com. That's in 10 bolt lots.