Hey, so I need some longer bolts than what came with my installation kit. What's an easy reliable source for mail ordering one-off orders of bolts, washers, and lock nuts? I only need a handful. obviously, they need to be of an appropriate grade for outdoor use. Usually I lean towards stainless.

Mail order? Don't you have a hardware store nearby? My nearby ACE carries metric stainless......just a thought.

My local hardware store does too so that's your first possibility. Also, many auto parts stores carry metric fasteners in various configurations and if there is a Fastenal shop near you they have nearly everything.

Finally, if there is nothing local, Bike Tools Etc. and Loose Screws carry metric stainless steel bolts and nuts in typical bicycle sizes.

My local True Value (bless their hearts!) has most of the metric stainless hardware I have needed
McMaster-Carr www.mcmaster.com have a large selection of EVERYTHING and ship fast.
Fastener Express www.fastener-express.com
Bolt Depot www.boltdepot.com
Fastenal www.fastenal.com

motorcycle shop, bike shop, marine shop.

Fastnall, industrial hardware , NAPA auto.

Thanks for the suggestions, folks. I already tried the local auto parts & hardware stores...some metric parts, but not in the right grade. Some stainless, but in english units. Lots of self-tapping hardware, which isn't what I happen to need at the moment. I need metric machine thread kind of stuff at the moment. I'll try mcmasters & graingers...forgot about them.

Why not get them from whoever sold you the bike/component?

I've found that most stores that ARE NOT selling fasteners outright have a VERY POOR idea of what is needed for any sort of job. SOmetimes there are surprises in some of the chain stores that you actually find what you want.

Add Grainger to the list of vendors for hardware and fasteners. Old time local hardware stores are the best for most hardware but some suffer badly at stocking metric anything.

Sockethead bolts are typically of high quality so that isnt a worry like many hex head fasteners. Watch out for the finish. Common black oxide finish rusts the worst. I always paint them if I have to use them.

-SP

Stainless is actually fairly weak material. You're not going to be able to find grade-8 hardware in stainless. Here's a good source of metric hardware that I use: https://www.mrmetric.com

What are you mounting to what kind of bike that thje supplied hardware will not work? Maybe you should not be doing that.

What grade are you looking for? Most cycling applications do not require aerospace grade hardware. I would think if it is good enough for a car or motorcycle it is good enough for bikes.

The guys at my local True Value are great but they get bewildered when I say I need a bolt. They ask what size and I say I am not sure. Ten minutes of pulling their drawers I have what I need. They think its odd I know what I want by sight and feel rather knowing I need a 3/39" x 55TPI T7 alloy cheese head stovebolt.

Some grades of stainless steel are fairly weak. The "300-series" alloys (304, 316, etc.) are extremely corrosion resistant but can't be heat treated and have modest mechanical properties. The "400-series" stainless steels are the "tool-steel" grades used for tools, cutlery, bearing balls, etc. and are fully heat treatable and can be very strong and/or hard. They sacrifice some corrosion resistance to get their superior mechanical properties.

Then again, very few bicycle components need the equivalent of Grade 8 bolt strength.

I got it the thing from REI. They don't sell bolts.

If it's good enough for car or motorcycle, it'd definitely be good enough for me, which is why I checked out the car parts stores. They didn't stock an m5 threaded bolt of sufficient length.


Graingers is definitely the easiest for me. I totally forgot about them, and I live a few towns over from one. It's been years since I thought about them.

It's just that what they supplied me with would work w/o considering other accessories, but doesn't work once you add in other crap going into the same installation. So, my bolt needs to be twice as long as the one they supplied.

I can calculate the combined shear and torque and tension loads, if need be. However I mostly don't bother. If it is graded at all, it is probably sufficient for the need. Occassionally, you run across stuff that is just not graded at all...that I generally try to avoid, just because I don't know what the hell it is. It could be tin for all I know.

Mostly what I care about on a bike is corrosion resistance, so it behaves well with mixed metals.