Stainless bolts seize up

[Andrew Troup]

For completeness, in case any future search throws this up for someone faced with a serious galling risk, or looking at designing high spec hardware:

Nitronic 50 is a great choice for nuts to run against 316 SS in crucial applications (but you'll probably have to make them from scratch or get them made)

ON EDIT: typo: should have read "Nitronic 60"

[Dennis.G]

One recommendation I had heard (in addition to anti-seize lub) is to never use an impact wrench to tighten SS bolts. Idea being heat is built up too fast. Tighten manually and SLOWLY.

As I don't own an impact wrench that part is easy for me. The SLOWLY makes more sense per comments in this tread.

[St. Elsewhere]

Hopefully some one with more expertise than me can expound on this, but I have been told never to use a mild steel wire wheel to clean up SS. It will imbed tiny bits of mild steel into the SS and cause pitting or surface rust. In the case of a bolt, it would probably go un noticed since it would most likely be out of sight. It seems to make sense to me, but may or may not be true. Does anybody know? _____Grant.

It is indeed true. I learned it "by doing". It was not a nut & bolt, but a SS fitting that I "cleaned up" with a wire brush, and made it worse because then it appeared to be rusting.

[delmarrey]

Originally Posted by gjordan

Hopefully some one with more expertise than me can expound on this, but I have been told never to use a mild steel wire wheel to clean up SS. It will imbed tiny bits of mild steel into the SS and cause pitting or surface rust. In the case of a bolt, it would probably go un noticed since it would most likely be out of sight. It seems to make sense to me, but may or may not be true. Does anybody know? _____Grant.

Yes! Iron transfers on to SS. Also any time one machines SS, like drilling, there is a transfer of iron. Even heating SS can cause iron to expel out of SS. This is why pacifying SS is important. >> http://www.euro-inox.org/pdf/map/Pas...ickling_EN.pdf

[hellosailor]

Cheechako-
If you consider that the carbon steel rollers, used for pipe bending, leave behind so much steel debris that they make stanchions and pulpits rust-speckled after just the bending operations, you may appreciate how much more micro debris a wire wheel leaves behind. You don't want any "silver" wire wheels near anything that can show rust.

As to using an impact wrench to tighten stainless bolts, or anything else?
No come on, really guys. Isn't that like sending someone out to buy polka-dot paint? The impact function is to break things free. Who applies impacts to torque down bolts? Besides the grease monkey at a muffler shop?

[St. Elsewhere]

Originally Posted by hellosailor

Cheechako-
As to using an impact wrench to tighten stainless bolts, or anything else?
No come on, really guys. Isn't that like sending someone out to buy polka-dot paint? The impact function is to break things free. Who applies impacts to torque down bolts? Besides the grease monkey at a muffler shop?

Actually, they are quite effective for installing large lag screws in heavy timbers. And, no, it was not done on a boat.

[hellosailor]

St.E-
No, really? You've had stainless lag screws seize up when installed in timber? Overheat when installed in timber?

[St. Elsewhere]

Originally Posted by hellosailor

St.E-

As to using an impact wrench to tighten stainless bolts, or anything else?

You've had stainless lag screws seize up when installed in timber?

My point was simply that the impact wrench is quite useful for driving and tightening galvanized lag screws in timbers, as opposed to only being used to break things loose. And though they do not seize up they do require a lot of cranking with a wrench. And, sorry for a bit of thread drift here.

[evm1024]

Just thought to drop a photo on the thread.

I received a new rail clamp from Seaview which included some stainless bolts. I lubed up all but one with lanocote (missed it somehow) and it galled up.

I was not turning fast but this bolt was used to hold the clamp tight to the rail so there was some torque involved to snug it up. When I felt the galling start I stopped and took stock.

PB Blaster and a lot of patience to the rescue.

The threads on the fitting are fine but as you can see the threads on the bolt are toast. One has to wonder as to the quality of the stainless steel and machining used to make this bolt. Dead on the first turns.

The lanocote coated bolts had zero problems.


Regards

[Cheechako]

Originally Posted by hellosailor

Cheechako-
If you consider that the carbon steel rollers, used for pipe bending, leave behind so much steel debris that they make stanchions and pulpits rust-speckled after just the bending operations, you may appreciate how much more micro debris a wire wheel leaves behind. You don't want any "silver" wire wheels near anything that can show rust.

As to using an impact wrench to tighten stainless bolts, or anything else?
No come on, really guys. Isn't that like sending someone out to buy polka-dot paint? The impact function is to break things free. Who applies impacts to torque down bolts? Besides the grease monkey at a muffler shop?

Oh , I agree totally, use a brass wire wheel if anything, but as I said earlier BUY NEW BOLTS! It seem s most of the galling problems I've had were in smaller screws like #10 or 3/16. I think any small ding on the threads can cause galling to start.... especially if you drive them tight with a hand drill like I do. What I like about non nylok nuts is you can snug them by hand quickly and will feel any resistance about to cause galling as you do.

[Andrew Troup]

Originally Posted by evm1024

.... I lubed up all but one with lanocote (missed it somehow) and it galled up.

... One has to wonder as to the quality of the stainless steel and machining used to make this bolt. Dead on the first turns.

The lanocote coated bolts had zero problems.

I think you might be being a little unfair on this specific point:

Although poor thread quality brings the problem to a head more quickly, galling is a characteristic behaviour of most stainless steel wherever clean and unlubricated surfaces are moved against each other in intimate contact, regardless of quality of material, or surface quality of threads.

[evm1024]

Originally Posted by Andrew Troup

I think you might be being a little unfair on this specific point:

Although poor thread quality brings the problem to a head more quickly, galling is a characteristic behaviour of most stainless steel wherever clean and unlubricated surfaces are moved against each other in intimate contact, regardless of quality of material, or surface quality of threads.

Likely you are right.

[Reefmagnet]

Originally Posted by hellosailor

Cheechako-
If you consider that the carbon steel rollers, used for pipe bending, leave behind so much steel debris that they make stanchions and pulpits rust-speckled after just the bending operations, you may appreciate how much more micro debris a wire wheel leaves behind. You don't want any "silver" wire wheels near anything that can show rust.

As to using an impact wrench to tighten stainless bolts, or anything else?
No come on, really guys. Isn't that like sending someone out to buy polka-dot paint? The impact function is to break things free. Who applies impacts to torque down bolts? Besides the grease monkey at a muffler shop?

Oops guilty as charged. Definitely wouldn't use one the tyre guys use, but my 10.8 V cordless impact wrench is the best thing ever for doing up stainless bolts on a boat. Never have a problem and I've used it hundreds of times. In fact it is the best tool I have used for philip head bolts and screws as it never damages the head of the screw (think about the tool used for removing cheese hard motorbike screws!). It also can undo stuff without breaking a sweat that might otherwise shear if done with hand tools. Best of all, it is fast and can get into tighter spaces than many hand tools.

[Cheechako]

Originally Posted by Andrew Troup

I think you might be being a little unfair on this specific point:

Although poor thread quality brings the problem to a head more quickly, galling is a characteristic behaviour of most stainless steel wherever clean and unlubricated surfaces are moved against each other in intimate contact, regardless of quality of material, or surface quality of threads.

I dont know guys, I think thread quality has a lot to do with it. Look at a thread under a microscope sometime. How sharp the cutter was, how the cutting was done (at best feed and speed, or simply as fast as they can?) makes a difference. How the thread is subsequently finished makes a difference too. (passivation takes away all the fuzzy/hairy/sharp material left on the tips of the threads). In addition, a nut cut to one side of the tolerance, and a bolt cut to the other side of the tolerance can make a big difference. Why is an aircraft SS bolt/ screw/threaded item so expensive? One reason is tolerances as well as finish and material control that machines better. There are a lot of reasons.
The high end turnbuckles on my Passport 47 were all 316 stainless, most are a combo of bronze and stainless to avoid galling. Why didnt these gall? Because the thread tolerances were held tight. The threads also looked like they may have been rolled. Not sure.[/

[brutb]

Use a SS wire brush or a SS wire brush with a shank for a hand drill. Works great. Available at Home Depot and Ace Hardware or for a more expensive version try West Marine...