Shaft plug materials?

Kim Bye

Kim Bye

AzB Silver Member
Silver Member
I have a few shafts that I need to change the threads on, so I need to plug the shafts.
I know phenolic is common to use, but I have a few McDermott i2/3 shafts and they seem to have a plastic plug of some sort and they screw on real nice.
Any one know what kind of plastic they use? I`m guessing some sort of ABS?
I know Acetal is a b***h to glue is ABS any better?
 
Plug it with a 2 inch long piece of 1/2 inch diameter phenolic rod ..... drill and tap it

Kim
 
One reason I think wood may not be the best choice as an insert is that it is mated with a metal pin. That metal pin is not going to change size with changes in humidity where as the wood insert will. So that perfect fit which was achieved when the cue was built will change every time your humidity goes up or down. Metal or plastic is much more stable and therefore won't change your fit between the pin and the insert. The other factor is durability, over years of use what materiel will wear out faster, wood or a synthetic material like phenolic?
 
WOOD WOOD and WOOD

If a properly administered maple plug is used it will out last you and me both if not abused.
disclaimer: used with 8-10-11-14 tpi....although I have 18 tpi pieces of maple that are just as good today as they were almost 20 years ago and used in my shop all the time.
IMO...ill techniques used are why people devise other methods to do a simple job.
 
Ned Morris use to love using olivewood....wonder if he still does for his shaft inserts (plugs).
 
BarenbruggeCues said:
If a properly administered maple plug is used it will out last you and me both if not abused.
disclaimer: used with 8-10-11-14 tpi....although I have 18 tpi pieces of maple that are just as good today as they were almost 20 years ago and used in my shop all the time.
IMO...ill techniques used are why people devise other methods to do a simple job.
Click to expand...

So how do you account for the change in dimensions of you your plug with change in humidity? If you have a tight fit at the time your insert was installed and a few months later the humidity spikes and the thread tightens up. The customer still screws his cue together like usual but now he has to use excessive force and consequentially is causing undue wear on the screw threads. A few months later the humidity changes to where it was when the insert was installed, and now your perfect fit is no longer perfect, it is sloppy. The only way around this as far as I know would be to treat your wooden insert with something to prevent it from changing with humidity, but doing so would plasticize your wood making it more like plastic than wood.
 
Yes I know that wood plugs can be used and I have some nice maple for that purpose, but I was looking for a plastic insert of some kind as I like the way it threads.
I wonder if plugs of different materials can be a way to adjust the feel of the hit?
 
Kim Bye said:
Yes I know that wood plugs can be used and I have some nice maple for that purpose, but I was looking for a plastic insert of some kind as I like the way it threads.
I wonder if plugs of different materials can be a way to adjust the feel of the hit?
Click to expand...

Kevlar is about the best synthetic I have tried.
Downsides are they are expensive and you can't tap them easily .
Acetal will work but you have to thread them on the outside and create a flat at the bottom so they won't slip out .
Regular nylon is just way too soft for my liking.
Phenolic dulls the crap out of taps .
Life will be a lot simpler if you have a live threader .
 
Canadian cue said:
So how do you account for the change in dimensions of you your plug with change in humidity? If you have a tight fit at the time your insert was installed and a few months later the humidity spikes and the thread tightens up. The customer still screws his cue together like usual but now he has to use excessive force and consequentially is causing undue wear on the screw threads. A few months later the humidity changes to where it was when the insert was installed, and now your perfect fit is no longer perfect, it is sloppy. The only way around this as far as I know would be to treat your wooden insert with something to prevent it from changing with humidity, but doing so would plasticize your wood making it more like plastic than wood.
Click to expand...

I guess all us cue makers have been doing it all wrong for all these years. McDermot, SouthWest, and almost everyone that uses a big pin.

Yes sometimes they do change with moisture but this is usually when it is exposed to moisture. Keep you cues in a case and don't leave it in the car all the time. Also good for keeping them straight too. I have been playing with the same shafts for 25 years and have had no problems.

Have found a coat of wax in the threads works wonders in sealing the threads and helps keep moisture out and acts as a lubricant.

I think someone mentioned nylon threads. The only problem is that you have to thread them in as epoxy will not hold by itself.

Phenolic inserts work well but you have to tap several times or it is very tight and difficult to tap.
 
Brickcues said:
I guess all us cue makers have been doing it all wrong for all these years. McDermot, SouthWest, and almost everyone that uses a big pin.

Yes sometimes they do change with moisture but this is usually when it is exposed to moisture. Keep you cues in a case and don't leave it in the car all the time. Also good for keeping them straight too. I have been playing with the same shafts for 25 years and have had no problems.

Have found a coat of wax in the threads works wonders in sealing the threads and helps keep moisture out and acts as a lubricant.

I think someone mentioned nylon threads. The only problem is that you have to thread them in as epoxy will not hold by itself.

Phenolic inserts work well but you have to tap several times or it is very tight and difficult to tap.
Click to expand...

I never said it was wrong.. I am simply saying it is not ideal. I use the big pin in my cues as well and have experimented with both. I have yet to come across a wood threaded cue that maintains an intimate fit between the pin and insert for many years. Will the cue still thread together and function? Of course it wont fail..but if you want to have a close tolerance fit between your pin and insert I believe wood may not be the best choice of material. It is not stable enough to maintain dimensional stability year round. I don't care how well you think you protect the wood, wood moves. So if you are satisfied with a fit which has some tolerance to account for the wood movement, then yes wood is fine.
 
JoeyInCali said:
Kevlar is about the best synthetic I have tried.
Downsides are they are expensive and you can't tap them easily .
Acetal will work but you have to thread them on the outside and create a flat at the bottom so they won't slip out .
Regular nylon is just way too soft for my liking.
Phenolic dulls the crap out of taps .
Life will be a lot simpler if you have a live threader .
Click to expand...

Thanks, some great observations there.
I totally see the value of the ability to do live tooling and I have a new lathe in the works, so I can do live tooling in a couple of months. The biggest I could fit now is a Weiss 290V-F, it`s only 700mm between the centers, but does all kinds of threads, has a 38mm spindle bore and 50-2000 rpm motor and it`s a lot more accurate than my Basic repair lathe.
So I`ll use the weiss for all tooling and detail machine work and the Basic for house cues and other stuff I need full length ability.
Not a perfect solution, but the cheapest and most practical compromise for now...
 
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