Why are my nuts blue?

[bluedog225]

I ordered fancy bolts, washers, and nuts.

The nuts are coated in blue wax. I’ve seen this before, but didn’t think much of it.

Why? Won’t that mess up my torque values?

 

[mike93lx]

First guess is to make them easily identified for inspection and then also as a lubricant/protectant? Although being galv, wax isn't likely protecting much

 

[cgrutt]

Complies with ASTM A563 specification

“Hot-dip and mechanically deposited zinc-coated Grade DH nuts shall be provided with an additional lubricant which shall be clean to the touch”

Waxed Nuts

Why are some hex nuts blue in color?

www.portlandbolt.com

 

[bluedog225]

I thought lubrication and torque values were mutually exclusive. That is, I vaguely recall reading that mating surfaces should be clean and dry.

 

[cgrutt]

I thought, lubrication and torque values were mutually exclusive. That is, I vaguely recall reading that mating surfaces should be clean and dry.

Believe its because the galvanization process adds a thick and sometimes rough coating to threads that can interfere with obtaining proper torque specification and/or cause galling.

 

[Dan in Pasadena]

Believe its because the galvanization process adds a thick and sometimes rough coating to threads that can interfere with obtaining proper torque specification and/or cause galling.

Depends on whether they were electro-plated or hot dip galvanized. I'd ASSUME automotive parts would only be electroplate. Hot dip is used on things like sign and light poles, etc. Maybe(?) that process would be used for heavy machinery?

 

[cgrutt]

Depends on whether they were electro-plated or hot dip galvanized. I'd ASSUME automotive parts would only be electroplate. Hot dip is used on things like sign and light poles, etc. Maybe(?) that process would be used for heavy machinery?

Says on receipt they are hot dipped.

 

[Dan in Pasadena]

Says on receipt they are hot dipped.

Ok, a bit surprising but my experience is that hot dip is a thicker coating. Granted my experience is in decades of heavy civil construction, not automotive parts.

 

[cgrutt]

Ok, a bit surprising but my experience is that hot dip is a thicker coating. Granted my experience is in decades of heavy civil construction, not automotive parts.

I'm just referring to fasteners that OP posted no idea what he's using them for.

 

[jrsulo]

Not gonna say anything !!!!!!!

 

[mike93lx]

Ok, a bit surprising but my experience is that hot dip is a thicker coating. Granted my experience is in decades of heavy civil construction, not automotive parts.

There aren't for an automotive application

 

[MoonRise]

IIRC, the OP is building a building with a 'deck' and stairs hanging off of a masonry structure.

As to the blue nuts, send flowers to the wife/SO and see if that helps.

Torque values for the desired preload and/or bolt tension can vary a LOT with 'dry' fasteners. Like 25% or more. Clean and consistently lubricated fasteners can bring that torque-vs-preload scatter down around 10%, but is more work to do all that.

Waxed hot dipped fasteners can help with more consistent torque-vs-preload values and help minimize galling of the rough zinc on rough zinc also.

And the spec for that grade nuts says that they WILL be lubricated with a visible (often blue) wax lubricant coating. See above paragraph for why.

 

[manwithtools]

For the OP's use any small variation in torque is inconsequential.

 

[brit vet]

Bluedog225 was lying in a hospital bed following a minor operation when a young gorgeous nurse approached his bed and asked how he was doing? “Are my testicles black” he asked struggling to speak while having gas and air. I have no idea said the nurse. Bluedog225 asked again “are my testicles black I need to know?” The nervous nurse said ok I’ll take a look and gently pealed back the bedsheet exposing bluedog225 equipment. She gently moved his willy to check his testicles then placed it back in place. No Mr. bluedog225 your testicles are not black she said. Bluedog225 pulled the Oxygen mask to one side and said “that was very nice nurse thank you for that but what I said was ARE MY TEST RESULTS BACK?”

 

[67King]

Ought to change title from "nuts" to "fasteners," lest suggestions to introduce yourself to Rosy Palmer

 

[Codyboy]

Torque values? Do you plan to actually torque that type of hardware with a torque wrench?

I've built several of these racks over the years that hold the equivalent weight of three VW bugs in the air for years.
Not a single torque wrench ever touched the hardware. About 5 or 6 ratatats or more seem to work great!

 

[In The Doghouse]

Did you by chance get a bowling ball for Christmas?