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Grinding Valve Seats


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Thanks

 

Professionals learn it at some point.

 

Looking for advice from someone with experience.

Buy good tools.

Take your time. Study the manual so you know what you are trying to do. But know that the stock seat configuration is not optimal for stainless valves. They will work, but there are better set ups.

Use Dychem bluing to accurately measure the surfaces.

The professionals know some tricks...gained from experience, to make the stainless valves work better with the OEM seats. These secrets are usually not shared.

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The other nice thing that a professional can provide that the everyday joe cant, or shouldn't is the good tools mentioned by CRF DOC. Bigborethumpers.com uses a serdi valve seat cutter. This machine was over $100,000 The advantage to this cutter is that there are formed cutters that skip the 3 or 5 angle cuts, and put a full radius on the seat so that it looks like a velocity stack. We can also check the guides to see if they are warn. If they are and you do a valve job and run the bike, you will end up eating a set of valves up soon.  

The everyday Joe can get stones and grind them in himself, but it can be expensive and very time consuming, and has potential to become a big pain in the butt if you don't do your homework. 

Valve job from bigborethumpers.com is $79. 

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I had heard some where the  Beryllium copper seats can be very toxic when ground if you are not careful, any truth to that?

 

Here is what I turned up on a quick Google search, another reason to let professionals with fluid lubricated cutting machines do the work. 

 

http://cr4.globalspec.com/thread/30093

 

Yes...Beryllium is toxic, worse when machined.

Some manufacturers still use Beryllium for NASCAR or Formula One seats.

Most of the alloys used in valve seat are NBC, (non-beryllium copper) such as NBC One. It is an alloy where Nickel and Silicone have replaced the Beryllium to create a hard wearing, highly heat conductive copper alloy material. This is also non toxic so it can be machined without extraordinary safety measures in place.

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Yes...Beryllium is toxic, worse when machined.

Some manufacturers still use Beryllium for NASCAR or Formula One seats.

Most of the alloys used in valve seat are NBC, (non-beryllium copper) such as NBC One. It is an alloy where Nickel and Silicone have replaced the Beryllium to create a hard wearing, highly heat conductive copper alloy material. This is also non toxic so it can be machined without extraordinary safety measures in place.

 

 

...and NBC is what is in the 05+ 450x's?  Not CuBe?

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...and NBC is what is in the 05+ 450x's?  Not CuBe?

 

No Sir...all Honda seats are Nodular Iron. Made using a powder Metallurgy process. It is a ductile seat but then hardened to Rc 32-38 and doesn't conduct heat as well as the Cu alloys.

If they were hardened to a lower Rc, the Titanium valves would last longer. In 2006, Honda refined the grain size and lowered the Rc slightly, and since then we have seen better valve wear from CRF's.

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A great seat material that we here at APE have used for ever is a Bronze blend. Great valve life. And great heat trans.

Not to mention its none toxic.

Yup...those are considered NBC materials. Bronze is mostly copper (usually 90%) with some Tin and other alloying elements. They often will replace the Tin with Manganese and Phosphorus and even a little Arsenic for good measure, to achieve the properties desired for seats and guides.

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Yes...Beryllium is toxic, worse when machined.

Some manufacturers still use Beryllium for NASCAR or Formula One seats.

Most of the alloys used in valve seat are NBC, (non-beryllium copper) such as NBC One. It is an alloy where Nickel and Silicone have replaced the Beryllium to create a hard wearing, highly heat conductive copper alloy material. This is also non toxic so it can be machined without extraordinary safety measures in place.

Beryllium copper is not toxic and not worse when machined.  It is considered a carcinigen.  You want to avoid dry grinding Beryllium copper.  Basically you don't want to inhale the dust.  There is no concerns with machining it.  And I hear now days it may be considered much less of a carcinigen than it has in the past.

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Beryllium copper is not toxic and not worse when machined.  It is considered a carcinigen.  You want to avoid dry grinding Beryllium copper.  Basically you don't want to inhale the dust.  There is no concerns with machining it.  And I hear now days it may be considered much less of a carcinigen than it has in the past.

 Wrong.

Here's from the MSDS:

Acute Effects:

Inhalation:  May cause irritation to the respiratory tract, sneezing, nausea, weakness, fever, rhinitis, nasopharyngitis, nosebleeds, bronchitis, pneumonitis, and rales.

Ingestion:  May cause nausea, vomiting, diarrhea, dyspnea and substernal pain.

Skin:  May cause irritation, dermatitis and chronic skin ulcers.

Eye:  May cause irritation.

Chronic Effects:

Inhalation:  May cause degeneration of mucous membrane, discoloration of skin and hair, ulceration and perforation of the nasal septum, coughing, shortness of breath, loss of appetite, weight loss, fatigue, cyanosis and cardiac or respiratory failure.

Ingestion:  May cause irritation to the gastrointestinal tract, chronic copper toxicity, damage to the nervous system, kidneys and liver.

Skin:  May cause dermatitis.

Eye:  No chronic effects recorded.

Medical Conditions Generally Aggravated by Exposure:  Pre-existing respiratory, gastric and pulmonary disorders and an increased risk for individuals with Wilson’s disease.

Target Organs:  Skin, lungs, nervous and circulatory systems, blood and kidneys.

CarcinogenicityBerylliumNTP:  Yes        IARC:  Yes         ACGIH:  Yes

 

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 Wrong.

Here's from the MSDS:

Acute Effects:

Inhalation:  May cause irritation to the respiratory tract, sneezing, nausea, weakness, fever, rhinitis, nasopharyngitis, nosebleeds, bronchitis, pneumonitis, and rales.

Ingestion:  May cause nausea, vomiting, diarrhea, dyspnea and substernal pain.

Skin:  May cause irritation, dermatitis and chronic skin ulcers.

Eye:  May cause irritation.

Chronic Effects:

Inhalation:  May cause degeneration of mucous membrane, discoloration of skin and hair, ulceration and perforation of the nasal septum, coughing, shortness of breath, loss of appetite, weight loss, fatigue, cyanosis and cardiac or respiratory failure.

Ingestion:  May cause irritation to the gastrointestinal tract, chronic copper toxicity, damage to the nervous system, kidneys and liver.

Skin:  May cause dermatitis.

Eye:  No chronic effects recorded.

Medical Conditions Generally Aggravated by Exposure:  Pre-existing respiratory, gastric and pulmonary disorders and an increased risk for individuals with Wilson’s disease.

Target Organs:  Skin, lungs, nervous and circulatory systems, blood and kidneys.

CarcinogenicityBerylliumNTP:  Yes        IARC:  Yes         ACGIH:  Yes

Is that for pure beryllium or beryllium copper?  I work in a large factory with 40 plus swiss type turning centers, mills, and laser cutters machining and cutting beryllium copper.  We have regular air monitoring and health inspection checks.  The only restiriction is no dry sanding.

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 Wrong.

Here's from the MSDS:

Acute Effects:

Inhalation:  May cause irritation to the respiratory tract, sneezing, nausea, weakness, fever, rhinitis, nasopharyngitis, nosebleeds, bronchitis, pneumonitis, and rales.

Ingestion:  May cause nausea, vomiting, diarrhea, dyspnea and substernal pain.

Skin:  May cause irritation, dermatitis and chronic skin ulcers.

Eye:  May cause irritation.

Chronic Effects:

Inhalation:  May cause degeneration of mucous membrane, discoloration of skin and hair, ulceration and perforation of the nasal septum, coughing, shortness of breath, loss of appetite, weight loss, fatigue, cyanosis and cardiac or respiratory failure.

Ingestion:  May cause irritation to the gastrointestinal tract, chronic copper toxicity, damage to the nervous system, kidneys and liver.

Skin:  May cause dermatitis.

Eye:  No chronic effects recorded.

Medical Conditions Generally Aggravated by Exposure:  Pre-existing respiratory, gastric and pulmonary disorders and an increased risk for individuals with Wilson’s disease.

Target Organs:  Skin, lungs, nervous and circulatory systems, blood and kidneys.

CarcinogenicityBerylliumNTP:  Yes        IARC:  Yes         ACGIH:  Yes

From MSDS:

 

M-25 and M-65 Alloys MSDS No. A01 March 21, 2014

Beryllium: The beryllium in this product is not known to cause acute health effects. Inhaling particulate containing beryllium may cause a serious, chronic lung disease called Chronic Beryllium Disease (CBD) in some individuals. See Section 2.2.5 Chronic (long-term health effects).

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Thanks

Professionals learn it at some point.

Looking for advice from someone with experience.

I did it for 10 years in an automotive machine shop. I ran a $150k Serdi 100. 3, 5, 7 angles, blends, radiuses (radii for the nerds) - it did it all. As stated above, it needs to be sent out. If not it will never be right, and if you're not gonna do it right why even bother taking it apart to replace the valves?

Or you could take the advice of someone who's never done it and try lapping the valves. Or try an old stone grinder. LMAO! Buy good tools - that's the best. You couldn't buy the carbide bits that a Serdi uses for what a valve job would cost.

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Is that for pure beryllium or beryllium copper?  I work in a large factory with 40 plus swiss type turning centers, mills, and laser cutters machining and cutting beryllium copper.  We have regular air monitoring and health inspection checks.  The only restiriction is no dry sanding.

 

That is for Beryllium Copper Alloys like UNS C17200 and UNS C17500. In it's solid form, the risks are minimal...unless you lick it 😛 .

It is the machining operations that make it more dangerous, anything that produces dust or particles.

I'm sure you have safety practices in place for disposing of shavings, millings, chips and fines. Even rags used to clean the machines must be labeled as Hazardous containing Beryllium. The Cooling/lubricating fluid must either be dedicated to only Be machining operations or be changed out prior to machining other alloys.

If these practices are not followed, I'd be seriously concerned for your long term health. These are OSHA practices...

 

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