JoeyInCali said:
The undersized tap might be the solution. I haven't tried boring the hole under 5/16 b/c I don't want to force the tap's pilot in and risk making the threads crooked.
The key I think is to make sure the first thread is full-depth. Force the tap in with tailstock until it's snug, then that's when you start hand-cranking the chuck.
3/8 10 and 3/8 11 lossen up after a while too .. I believe since we are dealing with wood here, an undersized tap with a smaller major might be the ticket. If you grind the threads, then you have to make the minor about 2 thou undersized to get a tight fit. But, I dunno if that pin would be dead straight. With an undersized tap, at least you know the minor of the pin and bored hole are dead nuts.
I think madagascar rosewood makes for nicer inserts. Oily and threads great.
That's one nice thing about inserts, You can sometimes turn the od between centers after tapping, and really true them up. I've turned It off a mandrel also, but it really needs to run dns, and having a good face on the insert during tapping is important to that, something that may be hard if the tap does'nt go in perfectly. I do a slight counter bore, so that may help, not sure, all I know is it's worked out for me in the end. I aggree though if the pin is'nt true, and the fit is snug it might fight against the faces. That's another problem with loose fits, they may need to be that way to utilize the faces for alignment if the pin is'nt perfect.
There is a downside If you just turn the od, and don't have mechanical bond there for the shaft, then your depending on the glue. I have used a few epoxies that would'nt hold the duration, but the polyurethane glues such as gorrilla or ultimate I have yet to see break down. I have also reglued a few mechanical inserts brought to me for repair with those type glues, and they seem to hold very well. I thought the expansion may cause issues, but so far they went in straight. I try not to glob the glue though. Alittle seems to go along way. I had a problem ferrule one time that would'nt hold tips no matter what glue I used, and that stuff did the trick. For me It's a nice last resort, but I don't use it unless I feel I need to.
I aggree undersized tap would be the way to go for snug threads in this case, afterall that's what it's for. just mentioning what I've seen, and how those 2 materials stack up, but in this case I would probably core with maple or maybe something that held better threads and was close in weight. I hate to change the feel very much because for some people even small changes can be hard for them to ajust to when they're use to a cue. The thing with the linen Is that It's lighter then brass inserts, so I suppose It's better suited when making ajustments in areas such as weight reduction or balance. It has an alright feel also once you get use to It, but it would be alittle harder then wood possibly. I have 2 shafts matched to My personal cue one brass and one linen. Then linen is lighter feeling in the joint, but as far as hit, they're pretty close. Delrin on the other hand Has a mushy hit like a springboard. I tell you what though I've used that gorilla glue on those too when they came in, and it stuck. I have'nt found another that would, but I have'nt tried the atlas stuff yet. I hope not to either, cause I would'nt care if I never see another delrin insert

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Guess you can tell I'm not a big fan of delrin Myself

Shame too cause It machines very easily. The pins I've seen those on were 3/8, possibly 10tpi If I remember corectly. I had a 3/8 pin cue that I made 2 shafts for, made the mistake of using It for one of the inserts. It totally changed the hit & feel. It may be alright for someone that likes that soft hit, but I can't stand It, It's like being trapped in a small room, My arsonal of strokes are restricted, and I've come to the conclusion that adapting to what little it does offer is a joke for My style of of play. Not even good for breaking IMO, but I know atleast 2 people with them in their cues, and they loved them, so to each his/her own I suppose.

I guess it's the same thing as people that like some deflection in their cue, or softer poly materials used in a cue, as where others don't. I like a cue that wants to go through the cueball Myself.

, But I understand different people have different needs in a cue.