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Getting ready to put the brass inserts in the end of my neck shaft for a bolt on neck.

I thought I would put a little epoxy in with them to strengthen the wood, and hopefully not glue
the internal threads too.

Does anybody do this?

Also, for those of you that use hanger bolts, what length do you use? So far all the ones I've found
locally look way too long, and would probably go completely thru the heel.

Thanks

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Horton, MI

Kirt,

I did not glue in the brass inserts. However, I did drill into the heel and inserted a wooden dowel so that the inserts weren't biting into end grain (I did a butt joint a la Mario). This is then covered by the heel cap.

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Joe Breault
Merrimack, NH
Perpetual novice

Ah yes, the dowel. I forgot all about that little trick.

Thanks

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Horton, MI

What size dowel? All the way through?

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Time is a great teacher, but unfortunately it kills all its pupils - Louis Hector Berlioz

Chansen / C hansen / C. Hansen / Christian Hansen - not a handle.

Christian

Equal or greater than the depth of the insert

I think it's a 1/2" dowel all the way through.

My inserts are somewhere around .420" diameter (don't have them here with me) so, I guess a 1/2" dowel would be enough.

It would be better than all end grain.

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Horton, MI

Thanks, that makes sense I guess. Anyone have a picture? I think I saw one somewhere but at the time wasn't thinking about my approach. I just read a whole slew of archived posts about using a bolt-on, flush joint. I had no idea so many people actually did this.

_________________
Time is a great teacher, but unfortunately it kills all its pupils - Louis Hector Berlioz

Chansen / C hansen / C. Hansen / Christian Hansen - not a handle.

Christian

You are saying you drill all the way through the heel? Or are you inserting your dowel from the side of the tenon and drill all the way through the tenon.

If I am using 1/4" inserts I drill for a not quite interference fit, 1/4" deeper than the insert then after gluing the dowel in place I drill through the dowel for proper thread engagement. this is in line with the insert not perpendicular to it. though I think I can see the benefit of doing so. The only reason I add the dowel as sacrificial wood to eliminate the chance of the neck splitting when tapping in the insert.

I believe that's what Mario does. Helps reinforce the heal against breaking too.

But what your saying makes sense too Michael.

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Horton, MI

Yeah, here it is.

Thanks Sir Grumpy!

http://www.proulxguitars.com/buildup/build9.htm

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Horton, MI

To answer the original question, I recommend getting as much thread engagement with the wood as possible and gluing them in with epoxy. I don't use a dowel. Threads and epoxy are plenty strong.

Mark

That's what I'm going to do Mark. I wanted to do a butt joint, but it didn't look like I had enough meat in the heel for the inserts. That's probably where the dowel really helps. I left a 1/4" tenon, just so I had a little bit more for thread engagement. Makes it look a little stronger, I think. Then I'll just have a shallow mortise in the headblock.

So here's where they're going. I'm going to screw them down a good 1/8" below the surface.


Thanks for all the help.

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Horton, MI

That looks good to me.

Be careful about how tight they are as you screw them in. It is possible to split the whole heel if they are too tight. If they seem to be turning hard, make the hole a little bigger, the glue will fill it back in.

Also after you glue them, some glue may squeeze up into the threads from the back side of the insert. After the glue is dry, use a 3 /16" drill to remove the glue and then clean up the threads with a tap.

Mark

Great.

Thanks to all.

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Horton, MI

I have wicked in CA after the inserts are seated.

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JJ
Napa, CA
http://www.DonohueGuitars.com

Hi Kirt,
I recently did a tutorial on this subject.Do a search and you should find it.
I use a 1/2" dowel all the way with the grain oriented "sideways".
I use a little ca on the threads.
I am using the course thread steel inserts from Mcfeelys with the hex drive.

If you are going to use the hanger bolts you will need to shorten them with a grinder or sander.

For all of those that wick in thin CA after taping in the insert. You do realize that the thin CA is not penetrating more than maybe a 1/16" to and 1/8" before it sets enough to prevent any deeper penetration. This will probably never be an issue as it will tend to prevent the treads form wanting to back out.

I use slow set medium CA on the inside of the bore and thread in the insert before it sets. This gives me more glued length than wicking.

I use the stainless inserts from McFeely. I use fish glue on the insert and the hole is coated also. I do that more to lubricate the thread cutting than anything else.
I suspect there is value added in having glue coat the entire surface if the wood all along the thread surfaces, but it would be tough to prove that. I don't know if fish glue holds at all to stainless steel. I haven't had to remove one of the inserts yet. I could to a quick test sometime.
I don't do dowels, but I do use 5 piece necks.

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

It's my understanding that fish glue sticks to almost anything. I was reading that it is good for gluing to glass even, so it surely would add some resistance to the inserts or, at least, strengthen the threads in the wood.

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Waddy

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