# Guitar string posts



## craig bumgarner (Mar 31, 2017)

Hi,

I'm a guitar builder, wood is my thing.   Metal, no so much, just don't have the tools.  Hoping some one who reads this forum might be able to make these for me or point me in the direction of someone who can.  Willing to pay of course.  I need brass or nickel silver string posts like this:  







Quite small as you can see.   I need six per guitar, so 2-3 dozen would be enough to get started but could buy more if that makes the job more attractive.  They need to be consistent in shape and size.   Hoping there is way of making a tool bit that can cut the shape consistently and quickly in one go, cut it off, do another.   Can supply a more detailed drawing.   You can email me direct at craig.bumgarner "AT" gmail.com if you like.     

If no one wants to take this on, does anyone have comments on how to make a tool bit that would make the shape in one shot?   I have access to a metal lathe and have used it some, not an expert.


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## JohnnyTK (Mar 31, 2017)

https://www.xometry.com/cnc/cnc-man...3CjHrpPGlPLiGgtl0ZzGt7nZbPqAMhjc-4RoCxOvw_wcB  Many other companies like this one on the web, first one that popped up for me.


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## T Bredehoft (Mar 31, 2017)

CNC's your best bet, a manual lathe will probably not be consistent enough. You're talking 1/4 in long, less than that in diameter. Holding it in a lathe and using a form tool might just pull it out of the lathe, rather than forming it.


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## craig bumgarner (Mar 31, 2017)

Thanks Tom,    I had not considered CNC.   How does CNC address a part like this?   Please excuse my ignorance, but I assumed it would be lathe work.


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## Tony Wells (Mar 31, 2017)

CNC is just the control method, used for many different machine types, one of which is a lathe. In a case of a contour like this, a tool is manipulated in both the X and Z axes to cut the desired profile. It would be the best method for making this part. Manually a form tool would likely be used, but creating the tool would be a bit (pardon the pun) tedious and not everyone is set up to grind it. A combination of different form tools would be a more practical approach from a manual standpoint.


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## craig bumgarner (Mar 31, 2017)

Okay, I see, thanks.


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## T Bredehoft (Mar 31, 2017)

craig bumgarner said:


> How does CNC address a part like this?



The machine does all the work, it may use different tools for different parts of the item, but it will spit them out 2 to the minute, too.


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## craig bumgarner (Mar 31, 2017)

Okay, thanks.    Any recommendations for free/inexpensive CAD app for submitting to CNC machinists.   I have Draftsight 2D and have used AutoCad, but h 2D CAD but nothing in the 3D realm.


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## RJSakowski (Mar 31, 2017)

CNC work on the lathe is not normal 3D.  You are basically cutting a 2D profile as the part turns.  At least, on your part.  I would think that anyone with CNC lathe capability could work from your Draftsight drawing.


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## Frank Ford (Mar 31, 2017)

I only have experience in manual lathe work, so I'd see this job as an ideal one for form tooling.   I reckon I'd stick a 5mm rod in the ol' collet, and turn the little end feature, then hit the rod with a form tool to make the concave profile.  Parting off with another form tool would provide the upper convex rounded shape.   If I were trying to make a big bunch of them, a little turret lathe might be just the thing.    Could take some hand work to get a good surface finish, of course - maybe by chucking the little end into a collet and spinning up to high rpms and using abrasive paper.   A simple fixture could hold the part for drilling accurately.

For sure, I'd want to know how this "string post" is to be mounted and used. . .


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## markba633csi (Mar 31, 2017)

Yes how does it attach to the gear mechanism? Or is there one? 
Mark S.


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## Frank Ford (Mar 31, 2017)

Frank Ford said:


> For sure, I'd want to know how this "string post" is to be mounted and used. . .



Ah, of course, I forgot the Selmer style tailpiece.   Any reason not to use a commercial one since they're relatively cheap?


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