Stainless Hardware

[trmcrft]

Stainless screws, nuts, washers, nylon standoffs, T-nuts and more. Button Heads, Socket Cap, Phillips Truss, Phillips Pan, Flat Countersunk. Outstanding prices in 25 piece packages. $2.99 flat rate shipping in the ConUS. You benefit from my 30+ years of stainless knowledge & service.

Trimcraftaviationrc.com

[kyleservicetech]

Originally Posted by trmcrft

Stainless screws, nuts, washers, nylon standoffs, T-nuts and more. Button Heads, Socket Cap, Phillips Truss, Phillips Pan, Flat Countersunk. Outstanding prices in 25 piece packages. $2.99 flat rate shipping in the ConUS. You benefit from my 30+ years of stainless knowledge & service.

Trimcraftaviationrc.com

SE Wisconsin?

As I remember at work, we had quite a bit of a problem with stainless steel nuts and bolts seizing after a period of time. We had to use anti seize compounds on all stainless hardware. One in particular was a 4-40 stainless cap screw into an aluminum die casting. That would seize so bad the screw would snap in half while trying to remove it. After the anti seize, no more problems.

Have you run into this???

[trmcrft]

Genoa City - about 45 mins from you.

I have not had this problem and I've been selling this type of stainless for use in general aviation airplanes for 30 years. Most ALL of the screws go into aluminum or alloy nut plates. Some years back, info was circulating about dis-similar metal corrosion too. Never had an issue with it.
If the 440 screw was threaded deep into the casting, I can see where some kind of issue would arise over time.

[kyleservicetech]

Originally Posted by trmcrft

Genoa City - about 45 mins from you.

I have not had this problem and I've been selling this type of stainless for use in general aviation airplanes for 30 years. Most ALL of the screws go into aluminum or alloy nut plates. Some years back, info was circulating about dis-similar metal corrosion too. Never had an issue with it.
If the 440 screw was threaded deep into the casting, I can see where some kind of issue would arise over time.

Yeah, it was screwed deep into the casting, Engineering made a change in the length of the screw.

Problem we had with some of the bigger 1/2 and 3/4 inch diameter hardware was it was exposed to outdoor weather including salt spray near the oceans.

Out of curiosity, what types of stainless hardware is available? Could be our Engineering department spec'd the wrong type of stainless?

[trmcrft]

Short answer on this one, I'll check my info tomorrow.
I can say most of it is commonly refered to as 18-8, 18% chrome, 8% nickel. It is a relatively soft material that you CAN twist the head off. It ain't no grade 8 bolt and should not be used as such! Tooth lock washers for instance are a harder material because of the job they do. Screws in 18-8 are generally a shiny material, lock washers are not do to a different metal mix. Both are corrosion resistant however. In my general aviation line, I sell some 'special' screws in stainless that are 125,000 PSI tensil strength and are used in stressed wing skins. They are positively ugly cause the color is like a burned charcoal briquet gray, but they Do Not Corrode!

Sorry for my long short answer! I will post more info tomorrow on stainless types in general use.

Gino

[kyleservicetech]

Originally Posted by trmcrft

Short answer on this one, I'll check my info tomorrow.
I can say most of it is commonly refered to as 18-8, 18% chrome, 8% nickel. It is a relatively soft material that you CAN twist the head off. It ain't no grade 8 bolt and should not be used as such! Tooth lock washers for instance are a harder material because of the job they do. Screws in 18-8 are generally a shiny material, lock washers are not do to a different metal mix. Both are corrosion resistant however. In my general aviation line, I sell some 'special' screws in stainless that are 125,000 PSI tensil strength and are used in stressed wing skins. They are positively ugly cause the color is like a burned charcoal briquet gray, but they Do Not Corrode!

Sorry for my long short answer! I will post more info tomorrow on stainless types in general use.

Gino

Good info!

Since you're from SE Wisconsin, you may be aware of http://www.speedymetals.com/.

This place sells all sorts of metal materials such as pipe, flat ware, angle, rounds and so on.

Nice thing about their web site, they describe the specifications and various uses for the metals they sell.

[JetPlaneFlyer]

You have the potential for really serious galvanic (dissimilar metal) corrosion between aluminium and stainless 'if' there is an electrolyte present. If water gets into the threads that's probably all it will take to set the corrosion off. The stainless won’t corrode but the aluminium threads will corrode severely. My day job is engineering piping systems in offshore oil platforms, which use lots of stainless, so trust me on this one. Also experience in my younger days of using stainless fasteners in aluminium motorbike parts confirms. It's especially bad if you are in a marine (salty) atmosphere because that massively accelerates the rate of galvanic corrosion.

To be honest though I don’t think it would be an issue for RC model parts because they are kept dry and as long as there is no electrolyte there is no galvanic corrosion. Also thread locking or anti seize compound prevents water getting into the threads and so reduces or eliminates the problem.

Steve

[trmcrft]

Thank you Steve! Good information is always welcome.

Gino

[trmcrft]

Here is MORE info than you ever wanted to know about types of stainless commonly used.

Now if I could just figure out how to get it to attach -

[kyleservicetech]

Originally Posted by trmcrft

Here is MORE info than you ever wanted to know about types of stainless commonly used.

Now if I could just figure out how to get it to attach -

Is this a hard copy or a web page?

If it's an electronic copy, the file format needs to match what's allowed in www.wattflyer.com. Or if it's a web page, just copy and paste the web page directly into this thread. (Like www.wattflyer.com)

If your data is not in an acceptable format, it can be converted to a PDF file which can be used just about anywhere.

[CNY_Dave]

I do know if you are doing a nut/bolt you are much better off with a stainless bolt and a non-stainless nut if you are not going to use anti-seize...

[trmcrft]

Originally Posted by kyleservicetech

Is this a hard copy or a web page?

If it's an electronic copy, the file format needs to match what's allowed in www.wattflyer.com. Or if it's a web page, just copy and paste the web page directly into this thread. (Like www.wattflyer.com)

If your data is not in an acceptable format, it can be converted to a PDF file which can be used just about anywhere.

I think the file is too large. It's a scan of a catalog page, I'll try to change the format.

[Snowdog1974]

Originally Posted by trmcrft

I think the file is too large. It's a scan of a catalog page, I'll try to change the format.

Here is the document that Gino was trying to upload:

[JetPlaneFlyer]

Originally Posted by CNY_Dave

I do know if you are doing a nut/bolt you are much better off with a stainless bolt and a non-stainless nut if you are not going to use anti-seize...

Well, yes and no. Stainless fasteners are much less prone to corrosion (excluding galvanic issues already mentioned) but they are very prone to galling. Galling is when the surfaces that rub against each other 'pick-up' and effectively weld themselves together: http://www.estainlesssteel.com/gallingofstainless.html

Probably not so much an issue for the tiny fasteners that we use and not a problem when the stainless screw is screwed into a different metal.. but something to watch for. In fact some sort of anti-seize compound/lubricant is more important when using stainless fasteners for this very reason.

Steve

[kyleservicetech]

Originally Posted by JetPlaneFlyer

Well, yes and no. Stainless fasteners are much less prone to corrosion (excluding galvanic issues already mentioned) but they are very prone to galling. Galling is when the surfaces that rub against each other 'pick-up' and effectively weld themselves together: http://www.estainlesssteel.com/gallingofstainless.html


Steve

Yup
Galling, that was the word my feable mind was looking for. We used anti-seize on all stainless fasteners for that reason.

Some of our customers specified all stainless or zinc plated hardware on all of their high voltage circuit breakers. They'd assemble the stuff and not use the included anti-seize compounds, and complain about the 1/2 inch diameter and larger bolts seizing.

[hayofstacks]

Its common for aluminium waterpumps bolts to break off and corrode on cae engines.