Metric Thread callout

[rchipper]

Greetings,

Lets say you have a blueprint that calls out a M10-6h thread. What pitch would this be? How do you know this?

Okay what about M6-6h, M12-6h?

There is a reason for my questions. I shall share after I get some feedback.

 

Thank you in advance for sharing your knowledge.

[crazy^millman]

When in doubt always go back to the customer. Make them give you what they want in writing. Make it to that and if it is wrong you don't take on the responsibility for scrapping parts and having to eat the cost. They don't want to supply you with the pitch then get in writing they will accept the parts as is with regards to the thread pitch.

Never cut a thread without knowing the pitch doing so is a recipe for failure.

[Werktuigbouwer]

Living in Europe, this is all standard for me.

M10 has a standard pitch of 1.5 mm, M6 has a pitch of 1 mm and M12 has a pitch of 1.75 mm.

If a customer wants a fine pitch thread (standard is coarse) then he or she should define it as M10x1

The x1 defines the pich. 

With you're call out M10-6h, the 6h defines the thread class. (6h is the standard thread class)

The link below, gives some information on the metric threads.

https://media.bossard.com/es-en/-/media/bossard-group/website/documents/technical-resources/en/f_079_en.pdf

Greetz, Jan

[crazy^millman]

11 minutes ago, Werktuigbouwer said:

Living in Europe, this is all standard for me.

M10 has a standard pitch of 1.5 mm, M6 has a pitch of 1 mm and M12 has a pitch of 1.75 mm.

If a customer wants a fine pitch thread (standard is coarse) then he or she should define it as M10x1

The x1 defines the pich. 

With you're call out M10-6h, the 6h defines the thread class. (6h is the standard thread class)

The link below, gives some information on the metric threads.

https://media.bossard.com/es-en/-/media/bossard-group/website/documents/technical-resources/en/f_079_en.pdf

Greetz, Jan

Yes we just had a customer want Fine and we refused to finish the programming until it was clarified. They told us Course and would deal with any issues with the customer. I said give me that in writing and we will proceed. They wanted me to take their word at it. I said nope update the PO with this listed and we will provide the programming. They fought me on it since they were late, but the customer said thank you for asking since so many assumed course and they wanted fine. Then they looked good for asking the hard question and the customer gave them more time to get the job done.

Goes back to Aaron's example of the Brown M&M's that David Lee Roth of Van Helen had in his contracts. People were not willing to take the time to separate the brown M&M's out of the candy dish they didn't read everything or care to do it right. Sometimes customers are testing the vendor are you caring to do it right or make assumptions? Do it right the first time then there is no worry about fixing it later.

[mwc815]

If you have cad data, you can measure the pilot hole size.

[crazy^millman]

54 minutes ago, mwc815 said:

If you have cad data, you can measure the pilot hole size.

Yes you can if the CAD is the controlling inspection data for anything missing on the print as a defense if they wanted something different than what you made. Seen that not help in some situations either where again a simple email or phone call takes the doubt out of the situation. Know what you know and prove what you know. You cannot be 100% sure what they want then stop and ask a question. Not that hard to do, but the problem is most people are scared to do it.

[Matthew Hajicek - Singularity]

Course is standard for metric, I believe it's part of the ISO spec.  If they want fine they need to specify; if they don't and you made it course it's to print.

[crazy^millman]

13 hours ago, Matthew Hajicek - Conventus said:

Course is standard for metric, I believe it's part of the ISO spec.  If they want fine they need to specify; if they don't and you made it course it's to print.

Now we are talking about provable stuff. Pull the spec and then use it to sell the part to the customer if they ever come back and ask why it is not what they wanted. Still say easier to get it confirmed than guess, but if you have the ISO Spec in your hand then you have all the proof you need. However if the customer doesn't feel the parts are correct or care about what spec you pull out still may not get paid for the work. So why risk it if you have any doubt? I am still waiting for the back story here that brought on this question.

[Newbeeee™]

On 5/20/2021 at 6:35 PM, Werktuigbouwer said:

Living in Europe, this is all standard for me.

M10 has a standard pitch of 1.5 mm, M6 has a pitch of 1 mm and M12 has a pitch of 1.75 mm.

If a customer wants a fine pitch thread (standard is coarse) then he or she should define it as M10x1

The x1 defines the pich. 

With you're call out M10-6h, the 6h defines the thread class. (6h is the standard thread class)

The link below, gives some information on the metric threads.

https://media.bossard.com/es-en/-/media/bossard-group/website/documents/technical-resources/en/f_079_en.pdf

Greetz, Jan

Yes - 100%.

[rchipper]

On 5/20/2021 at 9:35 AM, Werktuigbouwer said:

Living in Europe, this is all standard for me.

M10 has a standard pitch of 1.5 mm, M6 has a pitch of 1 mm and M12 has a pitch of 1.75 mm.

If a customer wants a fine pitch thread (standard is coarse) then he or she should define it as M10x1

The x1 defines the pich. 

With you're call out M10-6h, the 6h defines the thread class. (6h is the standard thread class)

The link below, gives some information on the metric threads.

https://media.bossard.com/es-en/-/media/bossard-group/website/documents/technical-resources/en/f_079_en.pdf

Greetz, Jan

Thank you. That is my understanding as well. 

[rchipper]

Thank you all for the replies.

I do agree that if the pitch is not called out on a metric thread it shall be a course pitch. If other than course is required it shall be called out with the intended pitch.

I was told by my QA department, (after I had programmed the threads in question), that if a metric thread does not call out the pitch it shall be "1. (across the board)". Whaaaat?

I tried to explain otherwise to no avail. So, I did reach out to the customer, (QA was afraid to do it), and they returned with, " no pitch call out designates course pitch and sent a clip of a course pitch chart similar to the one I showed QA.

Hens, 1.5, 1. and 1.75.

If there is something that we all agree to disagree on yes, ask the customer. But I was correct this time. Okay, so maybe I just wanted vindication.

Thanks again everyone!!!!!

[Leon82]

Years ago my place had a guy forget to put a threaded hole in a part.

 

So he told the boss to call the customer and see if they need it.

[Thad]

16 hours ago, rchipper said:

I was told by my QA department, (after I had programmed the threads in question), that if a metric thread does not call out the pitch it shall be "1. (across the board)".