Solenoid Contact metal

[M35A2-AZ]

Is the copper looking disk in the Solenoid made of copper or is it a contact type of copper alloy?
I need to make a new one that is why I am asking.

Thanks!!!

 

[Capt.Marion]

Which solenoid? The starter solenoid?

 

[cranetruck]

Here is one that failed on me a few years ago. How did the mating contact(s) survive?
IMHO, it's an alloy, pure copper would be too soft.
Seems like a new solenoid would be in order...

 

[glcaines]

I believe the starter solenoid disks are made from a tempered beryllium-copper alloy. If it is a BeCu alloy, be careful and not breathe the dust or cut yourself because anything containing beryllium is toxic.

 

[M35A2-AZ]

glcaines & cranetruck, Thanks for the info. I will try to find some beryllium-copper alloy or my just resurface the old one for now.

Capt.Marion, It is the starter solenoid.

Thanks again!!

 

[Economist]

I don't know how to link a post, but a couple of months ago, I had a long series of posts on how I did exactly that. I pulled the disk, resurfaced it on my lathe (now I know not to breathe the dust in!) and reinstalled. It works like a charm. I resurfaced both sides so that I can just flip it over next time. Good Luck!

 

[M35A2-AZ]

Economist, I think I read your post about your rebuild.
Thanks!!!

 

[texasjake]

Great job!!!

 

[Oldfart]

I doubt it is a Beryllium alloy. Beryllium is not a widely distributed ore and must be mined in what can best be described as pot hole operations. A little here and a little there. Beryllium is used in nuclear control rod manufacture and that demand makes its cost fairly high. When I was hot and heavy in the electric car business back in the late 70's the contact buttons were copper, nickel and silver and then silver soldered to the back plate. The most damage to the contacts takes place when breaking apart under a current load. On a starter, the current draw will drop when the engine starts and the starter can spin freely, thusly making it easier for the contacts to separate without arcing. On the other hand, getting off the starter before the engine starts will cause increased arcing when the contacts separate. Once significant pitting has occurred, arcing can become more severe.
.

 

[glcaines]

I doubt it is a Beryllium alloy. Beryllium is not a widely distributed ore and must be mined in what can best be described as pot hole operations. A little here and a little there. Beryllium is used in nuclear control rod manufacture and that demand makes its cost fairly high. When I was hot and heavy in the electric car business back in the late 70's the contact buttons were copper, nickel and silver and then silver soldered to the back plate. The most damage to the contacts takes place when breaking apart under a current load. On a starter, the current draw will drop when the engine starts and the starter can spin freely, thusly making it easier for the contacts to separate without arcing. On the other hand, getting off the starter before the engine starts will cause increased arcing when the contacts separate. Once significant pitting has occurred, arcing can become more severe.
.

Beryllium is a very common alloy of copper for many uses, not just electrical connectors. Most BeCu alloys range from about 0.25 - 3% beryllium. A small amount of beryllium will greatly change the properties of Cu. BeCu alloys have magnetic properties near unity. They machine easily without galling, they are significantly harder and have greater physical strength. They are also used to make springs. For electrical contacts, they have good physical strength, but their main benefit is the non-sparking, which is good for a connector to have. A good reference on BeCu alloys can be found at http://www.busbymetals.com/pdf/guide_to_be_cu.pdf .

 

[Oldfart]

Beryllium is a very common alloy of copper for many uses, not just electrical connectors. Most BeCu alloys range from about 0.25 - 3% beryllium. A small amount of beryllium will greatly change the properties of Cu. BeCu alloys have magnetic properties near unity. They machine easily without galling, they are significantly harder and have greater physical strength. They are also used to make springs. For electrical contacts, they have good physical strength, but their main benefit is the non-sparking, which is good for a connector to have. A good reference on BeCu alloys can be found at http://www.busbymetals.com/pdf/guide_to_be_cu.pdf .

Interesting information. My doubt is removed and I have saved the link. Clearly, a low percent of Beryllium may well be used in current day contactors. The low arcing properties should greatly extend the contactor life. When I was rebuilding EV contactors, the nickel and silver mixes were attempting to achieve the same end. Harden the contact and reduce arcing. ~~~ Back in the dark ages, my first job as a chemist was to analyze Beryllium Oxide for the contaminate Boron. As I recall, the major health concern was breathing the dust of Beryllium. Beryllioses was the illness and it was frequently discovered as many as 30 years after the exposure. Much the same as Asbestoses. I guess I am OK now since that was more than 50 years ago.

 

[glcaines]

Interesting information. My doubt is removed and I have saved the link. Clearly, a low percent of Beryllium may well be used in current day contactors. The low arcing properties should greatly extend the contactor life. When I was rebuilding EV contactors, the nickel and silver mixes were attempting to achieve the same end. Harden the contact and reduce arcing. ~~~ Back in the dark ages, my first job as a chemist was to analyze Beryllium Oxide for the contaminate Boron. As I recall, the major health concern was breathing the dust of Beryllium. Beryllioses was the illness and it was frequently discovered as many as 30 years after the exposure. Much the same as Asbestoses. I guess I am OK now since that was more than 50 years ago.

You are correct, breating the dust is very bad. Also, cuts from beryllium don't heal and sometimes the doctor will have to cut a lot of tissue away from the wound before it will heal. I didn't know you were a chemist. Another use for beryllium that you might find interesting is that it is almost transparent to radiation. For that reason, almost all windows on X-ray tubes are made from beryllium. In addition many windows on ion chambers are also made of beryllium for the same reason. Many gyroscope internals are also constructed of beryllium. The European Union is trying to totally ban the use of beryllium in the near future due to the toxicity. It is in so many products that I don't know how they will pull it off.

 

[Oldfart]

You are correct, breating the dust is very bad. Also, cuts from beryllium don't heal and sometimes the doctor will have to cut a lot of tissue away from the wound before it will heal. I didn't know you were a chemist. Another use for beryllium that you might find interesting is that it is almost transparent to radiation. For that reason, almost all windows on X-ray tubes are made from beryllium. In addition many windows on ion chambers are also made of beryllium for the same reason. Many gyroscope internals are also constructed of beryllium. The European Union is trying to totally ban the use of beryllium in the near future due to the toxicity. It is in so many products that I don't know how they will pull it off.

As I mentioned, my work was for a firm that supplied Beryllium for use in nuclear control rods. Because of the transparency to radiation, it could be used as a part of the rod without having any impact to the control process. ~~ The first step was to mine Beryl deposits which occurred in relativity small amounts. These were usually pretty hexagonal rocks that were found along the Colorado/Wyoming/New Mexico Front Range in deposits not much larger than the size of a semi trailer. The firms hope was to locate larger deposits that could avoid some of the mobilizations costs associated smaller deposits. The Beryllium was converted to the oxide as a means of purifying and for convenience in transportation prior to being made into the pure element. I have not kept up with any of that, but sources other than Beryl deposits must have come into use or it would remain a relatively scarce metal.
I am struck with the hazard phobia's that increasingly take place. I watched a Has/Mat team arrive at a rolled over semi last year. They all had disposable coveralls and breathing filters. The truck's fuel tank had leaked probably less than 5 gallons of diesel on the shoulder of the road. They spread high dollar adsorbent on everything and then shoveled the whole mess into about twenty 40 to 50 gallon drums which were sealed and hauled away. I later learned those drums were placed in slightly larger drums and then buried at the local land fill. The next thing you know we will be banning diesel fuel because of its toxicity. (check out http://www.lhup.edu/~dsimanek/dhmo.htm to see what I mean.)

 

[stumps]

Beryllium copper is commonly use for springs in electrical contacts. It is fairly low resistance, like copper, but unlike copper, it is springy when properly heat treated, and can withstand a near infinite number of flex relax cycles.

...But...

It is only occasionally used, by itself, as a contact material. It presents no special characteristics to that task. More commonly, a more suitable contact material is fused, or riveted to the beryllium copper spring, to form the contact assembly of a relay, or solenoid.

When it is talked of beryllium copper being non-sparking, what is being discussed is the lack of a glowing hot metal particle being dislodged when the metal is rapidly mechanically cut.... unlike steels. This property makes beryllium copper a valuable material for making hammers, chisels, and other tools used in explosive atmospheres... like around a leaking gasoline pipeline.

I am certain that most cheap starter solenoids are using a nearly pure, but work hardened, copper alloy for their contacts, Premium starter solenoids use a copper nickel silver alloy for their contacts because of its low welding and material transfer characteristics.

If you do a quick google search, you will find that virtually all starter solenoid parts, needed to rebuild your solenoid, are readily available.

-Chuck

 

[deuceaid]

I believe the starter solenoid disks are made from a tempered beryllium-copper alloy. If it is a BeCu alloy, be careful and not breathe the dust or cut yourself because anything containing beryllium is toxic.

and a carcinogen it WILL give you cancer


You could always work harden the copper with a hammer, but its gonna take time, and deform and thin out..

 

[Oldfart]

***, Premium starter solenoids use a copper nickel silver alloy for their contacts because of its low welding and material transfer characteristics.


-Chuck

I was a franchised electric car dealer back in the late 70's and the contacts used were heavy duty. We usually had failures in the contact points or buttons rather than anything else. My rebuilds involved the replacement of those components. Others would sell new solenoids, while we would actually repair the old ones. One of my vehicles used all Lucas electrical components (you know, Lucas, the Prince of Darkness). A constant failure was the emergency shut off switch. People on test drives sometimes would two foot the brake and accelerator causing the salesman to have to pull the switch. Breaking 300 to 700 amps DC at 96 volts causes quite an arc.

 

[kastein]

I believe the starter solenoid disks are made from a tempered beryllium-copper alloy. If it is a BeCu alloy, be careful and not breathe the dust or cut yourself because anything containing beryllium is toxic.

I'd bet on this or possibly a bit of phosphor included in the alloy? I forget, I know phosphor was included in bronze for some purposes and I seem to recall it being in copper alloys for various electronic uses also.

As for beryllium toxicity... yep... it is bad news. As a kid I broke open a couple of magnetrons out of old microwave ovens (beryllia insulators between the anode and the case!) without knowing that the purple ceramic was dangerous, I'm probably screwed in a couple decades. Oh well, too late now, do as I say not as I do!

 

[glcaines]

One of my vehicles used all Lucas electrical components (you know, Lucas, the Prince of Darkness). .

Not to get off-topic, but do you know why the English drink warm beer? They own Lucas refrigerators.

 

[Oldfart]

Not to get off-topic, but do you know why the English drink warm beer? They own Lucas refrigerators.

I don't care where your from, that's funny!!!Ghostdriver had several Jaguars and still has a cabriolet. I Know she will find this almost as funny as when she discovered her fuel was being run through the air conditioner to cool it down to avoid vapor lock.

 

[glcaines]

A friend of mine from Wales had a t-shirt with that on it. The question was on the front and the answer on the back.