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Starter brush holders - what is the metal?
Posted: Mon Feb 19, 2024 12:33 pm
by AdminJeff
Does anyone know what material the starter & generator brush holders are made from?
It sure acts and feels like Aluminum to me, but I'm not sure which alloy. It appears different suppliers used different metals.
One of them seems MUCH better made and sturdier and heavier than all the others but I cant quite make out the Vendor name.
I'm investigating having a high-quality reproduction made. My initial supplier feedback looks quite promising using both casting as well as precision CNC processes.
This one is obviously Stewart Warner and is also very well made:
I'm not looking for opinions on why or why not, just on what the best alloy to use might be.
AdminJeff
Re: Starter brush holders - what is the metal?
Posted: Mon Feb 19, 2024 12:39 pm
by speedytinc
Cuts, grinds & drills like aluminum. Does not deteriorate like pot metal.
Consider 6061-t6. Cuts fast & well for CNC machining.
Re: Starter brush holders - what is the metal?
Posted: Mon Feb 19, 2024 1:16 pm
by Kevin Pharis
Modern alloys will easily mechanically outperform any original casting material. Consult with your potential manufacturer as to their most common materials. Most likely billet machined will be 6061 and casting A356
Re: Starter brush holders - what is the metal?
Posted: Mon Feb 19, 2024 1:22 pm
by Ken Buhler
Send some to a metallurgist for assay. They will tell you the exact percentages of all contents.
Re: Starter brush holders - what is the metal?
Posted: Mon Feb 19, 2024 2:01 pm
by Jerry VanOoteghem
Originals are most likely die cast from Zamak, or similar.
https://en.wikipedia.org/wiki/Zamak
https://decoprod.com/design-support/zamak/
You might want to look at lost wax investment casting for new ones.
Re: Starter brush holders - what is the metal?
Posted: Mon Feb 19, 2024 2:12 pm
by TRDxB2
AdminJeff wrote: ↑Mon Feb 19, 2024 12:33 pm
Does anyone know what material the starter & generator brush holders are made from?
It sure acts and feels like Aluminum to me, but I'm not sure which alloy. It appears different suppliers used different metals.
One of them seems MUCH better made and sturdier and heavier than all the others but I cant quite make out the Vendor name.
I'm investigating having a high-quality reproduction made. My initial supplier feedback looks quite promising using both casting as well as precision CNC processes.
This one is obviously Stewart Warner and is also very well made:
brushholder Stewart Warner.jpg
I'm not looking for opinions on why or why not, just on what the best alloy to use might be.
AdminJeff
You might try to trace the manufacturers name with a piece of paper over the letters & rubbing over the letters gently with a lead pencil. Also might this be an old brush & the manufacturer is no longer in business?
https://en.wikipedia.org/wiki/Brush_(electric)
Carbon brushes are available in four main grade categories: carbon graphite, electrographitic, graphite, and metal graphite.
Exact composition of the brush depends on the application. Graphite/carbon powder is commonly used. Copper is used for better conductance (rare for AC applications). In order to maximize electrical conductivity and green strength, highly dendritic (electrolytic) copper powder is used.[5] Binders, mostly phenol or other resins or pitch, are mixed in so the powder holds its shape when compacted. Other additives include metal powders, and solid lubricants like MoS2, WS2. Much know-how and research is needed in order to define a brush grade mixture for each application or motor
This link describes several compositions of brushes & uses
https://www.repcoinc.com/about/blog/Wha ... sh-bd.html
Metal graphite carbon brushes for electrical motors are often made from natural graphite and fine metal powders. Copper is the most common, but silver, tin and lead are sometimes used. Metal graphite brushes are ideal for many applications due to low resistivity.
Re: Starter brush holders - what is the metal?
Posted: Mon Feb 19, 2024 2:29 pm
by Jerry VanOoteghem
TRDxB2 wrote: ↑Mon Feb 19, 2024 2:12 pm
AdminJeff wrote: ↑Mon Feb 19, 2024 12:33 pm
Does anyone know what material the starter & generator brush holders are made from?
It sure acts and feels like Aluminum to me, but I'm not sure which alloy. It appears different suppliers used different metals.
One of them seems MUCH better made and sturdier and heavier than all the others but I cant quite make out the Vendor name.
I'm investigating having a high-quality reproduction made. My initial supplier feedback looks quite promising using both casting as well as precision CNC processes.
This one is obviously Stewart Warner and is also very well made:
brushholder Stewart Warner.jpg
I'm not looking for opinions on why or why not, just on what the best alloy to use might be.
AdminJeff
You might try to trace the manufacturers name with a piece of paper over the letters & rubbing over the letters gently with a lead pencil. Also might this be an old brush & the manufacturer is no longer in business?
https://en.wikipedia.org/wiki/Brush_(electric)
Carbon brushes are available in four main grade categories: carbon graphite, electrographitic, graphite, and metal graphite.
Exact composition of the brush depends on the application. Graphite/carbon powder is commonly used. Copper is used for better conductance (rare for AC applications). In order to maximize electrical conductivity and green strength, highly dendritic (electrolytic) copper powder is used.[5] Binders, mostly phenol or other resins or pitch, are mixed in so the powder holds its shape when compacted. Other additives include metal powders, and solid lubricants like MoS2, WS2. Much know-how and research is needed in order to define a brush grade mixture for each application or motor
This link describes several compositions of brushes & uses
https://www.repcoinc.com/about/blog/Wha ... sh-bd.html
Metal graphite carbon brushes for electrical motors are often made from natural graphite and fine metal powders. Copper is the most common, but silver, tin and lead are sometimes used. Metal graphite brushes are ideal for many applications due to low resistivity.
Brush HOLDERS. Not the brushes.
Re: Starter brush holders - what is the metal?
Posted: Mon Feb 19, 2024 2:40 pm
by Dan McEachern
Jeff- take one to a scrap dealer/ scrap yard and have them shoot it with an ZRF gun. That will tell you the alloy rather than sending one to a testing lab. Even if you have to pay them some $$$ to do it. My guess is aluminum, similar to the magnet support spools for the flywheel.
Re: Starter brush holders - what is the metal?
Posted: Mon Feb 19, 2024 5:21 pm
by AdminJeff
Dan McEachern wrote: ↑Mon Feb 19, 2024 2:40 pm
Jeff- take one to a scrap dealer/ scrap yard and have them shoot it with an ZRF gun. That will tell you the alloy rather than sending one to a testing lab. Even if you have to pay them some $$$ to do it. My guess is aluminum, similar to the magnet support spools for the flywheel.
that is an interesting idea!
Re: Starter brush holders - what is the metal?
Posted: Mon Feb 19, 2024 5:24 pm
by AdminJeff
Jerry VanOoteghem wrote: ↑Mon Feb 19, 2024 2:01 pm
You might want to look at lost wax investment casting for new ones.
I had a lead on this as well! Its pretty interesting. The molds are expensive ($1000's) no matter which casting process is used. The CNC process doesn't incur that...
Re: Starter brush holders - what is the metal?
Posted: Mon Feb 19, 2024 6:23 pm
by Jerry VanOoteghem
AdminJeff wrote: ↑Mon Feb 19, 2024 5:24 pm
Jerry VanOoteghem wrote: ↑Mon Feb 19, 2024 2:01 pm
You might want to look at lost wax investment casting for new ones.
I had a lead on this as well! Its pretty interesting. The molds are expensive ($1000's) no matter which casting process is used. The CNC process doesn't incur that...
I think the wax can be 3D printed now, cutting down on mold costs.
Re: Starter brush holders - what is the metal?
Posted: Mon Feb 19, 2024 10:08 pm
by Allan
If wax molds can be printed in multiples, that should bring costs way down. Previously, a wax mold was cast using an original part as a pattern. This wax casting is destroyed in the metal casting process, so the whole pattern making process has to be gone through to make subsequent castings.
Allan from down under.
Re: Starter brush holders - what is the metal?
Posted: Mon Mar 18, 2024 11:17 am
by AdminJeff
Mystery solved - at least for this particular one!! I'm sure its whatever scrap metal they could find 100 years ago, all melted down.