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Hey Gang:

I'm gonna try hanger bolts for my next one. Was wondering what size would be most appropriate. 3/16 - 1/4? Just not sure. Anyone else using this method?

-Mark

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#/16" scares me a bit, unless you have a laminate neck with hardwood in the center section. You might consider inserting a hardwood dowel to screw the hanger bolt into if you want a one piece neck. I'd go with the 1/4" either way.

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"An adventure is only an inconvenience rightly considered. An inconvenience is an adventure wrongly considered." G. K. Chesterton.

Thanks Steve.

I am inserting a dowel. Am just not sure of the size hanger bolt. 1/4 sounds right though, but with no experience, hey, how does one know?    This neck does have a rosewood laminate.

Thanks!

-Mark Mark Tripp38975.6916550926

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Pullman, WA

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1/4" works fine for me, but I'd also bet 3/16" would be enough....

in this sort of application it isn't the size of bolt per se which is of importance but rather the depth of the thread which provides the grip. i would go along with mario and say use the 1/4".

I do not know for sure about wood. I do know about metal.   In metal the strength is much more about the thread height than the depth of the screw. In metal, after you have 4 complete threads in, there is little to no strength gained by going deeper. In other words, if the screw is in 4 revolutions, it is just as strong as if it were in 25 revolutions. The failure is in shear, that is why it is true.

I used to design dental implants so I had to do these calculations. That was for stainless steel, but I suspect wood isn't much different.

For screws, the important features for strength are the thread height and ensuring enough depth for the screws. If the hole is drilled with too large a diameter for these hanger bolts, strength will be significantly reduced - be carefull. In wood I would never recommend only 4 revolutions for maximum strength. The whole thread and wood combination is not as consistent in material or tolerances as metal screws.

3/16" would probably work, but the threads are not as tall as 1/4". Unless space is limited, I'd go with 1/4".

_________________
"An adventure is only an inconvenience rightly considered. An inconvenience is an adventure wrongly considered." G. K. Chesterton.

Great post Steve. Thanks for the insight.

Excellent input folks! Thanks very much.

I'm going with 1/4"

-Mark

_________________
Pullman, WA

The more I know, the more I know I don't know.

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OR
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