Ceramic Screws

[bkcooler]

Anyone tried or researched ceramic screws?
I had some rust around the screws due to electrolysis from differing metals (aluminum and SS).
Just wondering if it is feasible.

Thanks.

[conchydong]

Ceramics might be a little brittle, I know the knives are. Perhaps some of the new plastics like Delrin may have potential in the future. At least thinking out of the box is good.

[Dominick]

Here is some thinking outside of the box.  I know absolutely nothing about metallurgy but I would think (notice I did not say assume) that an alloy of aluminum and stainless steel is a possibility.  If that is possible do you think the alloy would corrode anyhow?  Just thinking out loud and outside the box.  Dominick

[aus bass]

If your using the screws in an Aluminium boat try dipping your screws in Lanolin grease, it provides a protective coating and prevents the metals from coming into direct contact and hence prevents galvanic corrosion (falsely called electrolosis).

[whalebreath]

If ....using the screws in an Aluminium boat try dipping your screws in Lanolin grease..

Like this stuff  http://www.fluid-film.com/

it provides a protective coating and prevents the metals from coming into direct contact and hence prevents galvanic corrosion (falsely called electrolosis)

Roger that.

[Mike La Franchie]

Here is some thinking outside of the box.  I know absolutely nothing about metallurgy but I would think (notice I did not say assume) that an alloy of aluminum and stainless steel is a possibility.  If that is possible do you think the alloy would corrode anyhow?  Just thinking out loud and outside the box.  Dominick

I'm pretty sure aluminuim and steel will not alloy. Aluminuim forms a microstructure called hexagonal close packed, steel (inc stainless steel) microstructure is either face centred cubic or body centred cubic depending on its heat treatment. I believe the microstructure needs to be the same to mix well I.e. form an alloy.

Of interest is that only the FCC microstructure is magnetic. The stainless steels which are not magnetic have a bcc structure.

I am not a meturallegest and know only enough to get myself into trouble.

Ceramic is very hard i.e a plate does not scratch but your stainless benchtop does. but ceramics downside is that it is very brittle I.e dropped plate breaks rather than dent.

Forming a thread on on a ceramic screw would be difficult.
They would need to be cast, I.e formed then fired like pottery.
The advantage to metals is that the thread can be cut into a length of round bar stock, making them easy to manufacture.

Plastics can be hard and brittle or soft and bendy, depending on their recipie.

I can see coarse thread screws like these in graphite body sideplates could be replaced by an appropriate plastic. Perhaps nylon would be strong enough, nylon screws are already readily available.

Fine thread screws thread into metal components, are more difficult. The thread is so small that the material needs to be very machinable to cut the thread into the screw, yet needs to be hard enough to retain enough strength when each individual thread is very thin.

I think there is probably a plastic out there that could do this.

However the problem is mostly galvanic corrosion between dissimilar metals.  A grease barrier between he different metals is a good solution.

[Ron Jones]

If I had all the money in the world I would use Monel for every fastener in every reel.

Ron

[Fullstrike]

I own a plate alloy boat (Black Lab). Any stainless screw is coated with Tef Gel before installing in the aluminum. If you don't it will become  "welded" to the plate in short order.

[Dominick]

If I had all the money in the world I would use Monel for every fastener in every reel. Ron

Noyb72:  I had never heard of Monel so I Googled it.  As far as the information on Monel it is highly corrosive in saltwater and reacts galvanically to aluminum.  Dominick

[Irish Jigger]

Monel is regarded as the best material for propeller shafts in inboard engined sea going boats. Very expensive though.

[conchydong]

We use monel for our wire line trolling rigs. It is expensive but more pliable than the stainless steel wire line. Good stuff.

[Alto Mare]

Conchydong, what type of reels do you use for wire trolling, just a curiosity.
Sal.

[conchydong]

Sal, I used to use a Penn 6/0 chrome spool but have switched over to a 9/0 chrome spool. If we are high speeding for Wahoo, we attach a trolling weight ,  heavy shock leader and a high speed lure. If it is for King fish, I will switch to a planer, a  lighter shock leader and a bonito or mullet strip bait or a rigged ballyhoo behind a sea witch either pink or chartreuse. I was interested in one of the Accuframes for the 9/0 but it is not cost effective. I could almost buy a used International for the cost of the frame.

[Alto Mare]

Thanks for the answer Conchy, I forgot that you're a Penn buddy .
Sal

[Ron Jones]

We use monel in the engine room on nuclear submarines. It will corrode only with funky chemicals added to the water. Boats run for forty years and when they are finally taken apart most of the monel looks brand new.
Ron