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I used to use the hillman. I now use these https://www.mcmaster.com/catalog/126/3508. No issues since. I also use the associated install bit.

Still, it just seemed to make sense to me to add some strength

I use to have the same problems with screw inserts. I went to the new Cumpiano M&T joint, where you make the tenon about 1/4" narrower than the size of the mortise, then line the tenon with a hardwood with the grain going straight up and down. I use structural epoxy to glue the strips in (I use African blackood when I have it)
https://www.cumpiano.com/an-improved-neck-body-joint

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Joe Beaver
Maker of Sawdust

^^ that is what I am talking about. (sort of). But that is the idea.

I'm a fan of these inserts as well and use them on any customer necks where they request threaded inserts installed. What I like in particular about these is the very coarse thread and small minor thread diameter. This means than you use a very small pilot drill and there's a lot of meat between the wood fibers cut by the thread.

I've also started flooding with thin CA glue to harden up the grain in the hole.

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

the insert you posted from McMaster carr don't have the same thead and are prone to failure. I just thew out 100 of them

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Scrolling down on the page Mike linked to are the softwood broken thread zinc inserts I use. The thread bites deeper and holds better than any of the hardwood continuous thread inserts I have tried. I think the broken thread also allows the thin CA to saturate the wood around the insert body better.

https://www.mcmaster.com/catalog/126/3508

so are hillman, especially on install. (aka big box store products). not had a failure with MM Carr

hillmans crack at the top where u screw them in. MM Carr has a special insert tool to avoid this (sized for the insert). Once they are in the wood safely, they are all pretty much the same. But getting to that point is the issue.

You can find hillman at lowes

I've been using these end grain inserts for over a decade now. They all work if you install them correctly. After the install, flood with CA glue and you're fine. If for some reason, you mess up with one of them - you could always drill and glue in a dowel - and then reinstall the insert. Or you can just drill a hole the size of the threads and just glue in with a good quality epoxy.

It is important that you use the right drill bit and get them in straight - trying to straighten them after you've begun the installation will cause problems. My suggestion is drill about 20 holes in some spare end-grain Mahogany - and practice. After that, you'll have the process down and won't ever struggle again.

Other suggestions for installation that I had to learn the hard way:

1. After drilling of the pilot hole, but before you try to screw in the insert, clamp something on both sides of the tenon or heel or whatever you are screwing into. Even just the threads to an insert can be a wedge that can make wood separate, if there is no support on the outside of the wood.

2. I have found the best way to install threaded inserts and keep them straight is with a bolt that has had its head sawed off, and at least two nuts screwed onto it and jammed together tightly, and then the bolt chucked up in the drill press. DON'T TURN ON THE DRILL PRESS!!! Just turn it by hand. Inserts go in like butter, and are 100% vertical.

Agree with both points in that post, Don.

They both come from pain and regret, Barry. I could offer some cringe-worthy posts in the "oops what a dum-dum" thread when it comes to messing up threaded inserts. It's funny, because now that I have a decent idea of how to deal with inserts, I'm building with a dovetail joint.

Well Don that made me laugh because I've done the exact same thing

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Steve Smith
"Music is what feelings sound like"

But our jigs have the cleanest threaded inserts, Steve! Always look on the bright side of life (whistle).

I've built with both, probably equally. But lately, I've been moving towards using a mortise and tenon with a cantilevered neck/floating fingerboard and using the adjustable neck joint I've used on banjos for years. Much more banjo like approach to necks, so I guess it gets me more into my comfort zone.

If you're careful with inserts, they work great. I have found that on mahogany necks in particular, sometimes flooding the inserts with thin CA (which I do) can wick through the heel and show up as spots on the outside of the heel. Not good, but using medium CA instead seems to take care of that.

The drill press method that Don posted has been probably the best of what I've used on banjos. Trying to do it freehand with the "proper" tool for setting inserts has led to some difficulties for me here and there. Getting the things in straight is the key.

Dave