Tenons for shafts help Please

JTs cuerepair

AzB Silver Member
Silver Member
I'm sure most of you guys don't repair to many broken tenons in shafts as you mostly make new shafts. Here is my question, I have been looking for a good place to buy tenons. Do you guys buy them or make them. Do you thread them in or not. If you do buy them can you tell me where to get good tenons for cue use? If you do make then can you share some spec's.

Thanks...
 
I make them from left over maple coring wood or broken shafts.....
I also have some maple dowels in my traveling tournament box
 
I am not a cuemaker but anyway maybe I can give you an answer.

Unique sells fluted tenons (but I am not sure if this are maple tenons).

I make my tenons by myself of maple and screw them in (5/16-18 thread) 25 - 30 mm deep. Tenon dia sligthly less than 7.9 mm; thread depth ca. 0.87 mm.

Here is a video:

http://www.youtube.com/watch?v=t9ldnWNKJjo

regards
Olaf
 
I make them from maple shafts. I turn them to 5/16 or 1/4 depending on shaft dia. File a few glue rings and glue it in a drilled hole with 5 min.. Turn it to fit the hole in ferrule. File a few glue rings on it and glue on a slip fit ferrule with 5 min.

Never had one break, crack, or come loose.

I used to thread both ends of the new tenon but learned that it was not necessary. I believe that the threading actually weakens the tenon. 90% of the ferrules that I have replaced have been threaded.

just my personal opinion

Kim
 
http://www.rockler.com/product.cfm?page=2503&site=ROCKLER
21113-01-200.jpg

3/8 by 2 inches will serve you well.
 
Pretty much the same as Kim.

I will hold the edge of a file to the tenon and make small v groove threads.
This is for the part of the tenon that will fit in the shaft and the ferrule.

I do tap the shaft. I use Tite Bond on the tenon. I to feel this is more than adequate and have never experienced a problem from doing it this way.

Altho I do like watching Cue Tips videos and would love to have a lathe like his.
 
I believe that the threading actually weakens the tenon. 90% of the ferrules that I have replaced have been threaded.

just my personal opinion

Kim

Astute observation.
I've never seen a minor diameter add strength.
So if the above statement is true, why the grooves?
Going into a blind hole, one might want a means of pressure relief
but a tenon intended for a thru-ferrule doesn't need threads.
You know how epoxy has that nasty habit of wicking into wood?
The tenon doesn't need threads so why weaken it?
This is also an instance where bigger is better.

50 yrs ago when LBM wasn't yet available for ferrules and cotton-fibre ferrules were the norm,
you wanted as much wall thickness of the ferrule as you could get, within reason.
That and epoxy hadn't been invented yet either.
Today we have LBM, Aegis, Ivorine, etc. & etc. which are 'wound' around the center, rod or tube.
This is some incredibly strong mtrl., take advantage of that fact.
All plastics considered for this application weigh more than wood but today, you can use much less of it.
Put the strength back in the wood/tenon where it belongs.
L/D isn't my intent here, it's just a welcome side-effect.

Another opinion, KJ
 
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Astute observation.
I've never seen a minor diameter add strength.
So if the above statement is true, why the grooves?
Going into a blind hole, one might want a means of pressure relief
but a tenon intended for a thru-ferrule doesn't need threads.
You know how epoxy has that nasty habit of wicking into wood?
The tenon doesn't need threads so why weaken it?
This is also an instance where bigger is better.



Another opinion, KJ

Epoxy wicking into wood ? There's another good reason to use a slow-set epoxy. Barrier coat, recoat ? But, if you gotta do it in 30 minutes b/c customer is waiting ?
Epoxy also has a bad habit of shrinking. Wood has a nasty habit of shrinking and expanding. How many McDermott ferrules have you seen break on top b/c of the threads as opposed to the bottom showing a nasty gap b/c it has moved ( McD used a long-pot life glue ) ?
If one can find a ferrule material strong enough to have 5/16 as through hole and 15 thou or so a side for threads, threads got a place there imho.

Somewhere between 5/16 UNC and 3/8 UNF might be a sweet spot. :grin-square:

ps
I hate the smell of lacq sanding sealer. It should be gone after this coffee. :grin:
 

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Before I started actually doing tournament repairs,I preferred to actually take the time to just fabricate the tenon and ferrule on the spot,rather than just pull a tenon and ferrule out of the drawer and have them ready to go.

I keep things like this on hand now.

Until now,I just drilled the hole out. I'll be boring them out with live tooling in the next couple weeks.

Because I was drilling them,I filed the bottom to match the 118 degree included angle at the tip of the drill bit,trying to really get it to touch at the bottom,and get it to solidify with the help of the glue,rather than leave empty space.

I know that hydraulic effect when pushing the tenon into the hole can wreck the shaft if used improperly,and haven't had to deal with that.

My experience with this has been the exact opposite. The right amount of certain glues and epoxies I've tried and a snug fit inside the hole actually PULLS the tenon down into the hole,rather than having it pushed back out.

I've never questioned it,it just happens and you don't have to have it in the lathe and hold the tenon with tailstock pressure.

With the front threaded with a modified compression die,I leave the rest of the tenon at .325 or so,which leaves a locating diameter,and counterbore the ferrule,leaving the slight undercut about .200 or so into the ferrule,rather than the very bottom.

Before I kept prepped tenons,I'd take a couple truing passes after the glue set good,then thread it.

I also try to get the tip of the tenon as close as I can to the bottom of the tapped hole inside the ferrule,to avoid space being left that has to be filled by glue that might get hot and break loose because the customer left the cue in his car in 100 degree heat. I've seen this cause a buzz a couple times.

All this is based on using a 5/16-18 threaded ferrule,void if the tenon is meant to maintain the thin-walled Meucci ferrule the customer wants,LOL. Tommy D.
 
Epoxy wicking into wood ? There's another good reason to use a slow-set epoxy. Barrier coat, recoat ? But, if you gotta do it in 30 minutes b/c customer is waiting ?
Epoxy also has a bad habit of shrinking. Wood has a nasty habit of shrinking and expanding. How many McDermott ferrules have you seen break on top b/c of the threads as opposed to the bottom showing a nasty gap b/c it has moved ( McD used a long-pot life glue ) ?
If one can find a ferrule material strong enough to have 5/16 as through hole and 15 thou or so a side for threads, threads got a place there imho.

Somewhere between 5/16 UNC and 3/8 UNF might be a sweet spot. :grin-square:

ps
I hate the smell of lacq sanding sealer. It should be gone after this coffee. :grin:

For years, when McDermott had problems with ferrules coming loose, they, along with most house cues, used fiber ferrules. Fiber ferrules are/were extremely strong. They were impossible to break. Their drawback however is that they were made from cotton and they absorbed moisture like a sponge. In so doing they would shrink in length and swell in width. This is what caused the tenon to stick out of the end knocking the tip off, developing a large gap behind the ferrule, the ferrule becoming larger than the shaft and, once the dimensions had changed enough, glue failure.

Dick
 
Epoxy wicking into wood ? There's another good reason to use a slow-set epoxy. Barrier coat, recoat ? But, if you gotta do it in 30 minutes b/c customer is waiting ?
Epoxy also has a bad habit of shrinking. Wood has a nasty habit of shrinking and expanding. How many McDermott ferrules have you seen break on top b/c of the threads as opposed to the bottom showing a nasty gap b/c it has moved ( McD used a long-pot life glue ) ?
If one can find a ferrule material strong enough to have 5/16 as through hole and 15 thou or so a side for threads, threads got a place there imho.

Somewhere between 5/16 UNC and 3/8 UNF might be a sweet spot. :grin-square:

I don't do ferrule installs on the spot.
If the client wants me to do the task, his new ferrule will be ready tomorrow.
I use slow-cure on everything.

The ferrules that you refer to that were known for expanding/contracting were cotton-fibre.
Since the company that made them no longer exists (their building burned down), their ferrules aren't used anymore.

As to the happy-medium btwn 5/16 & 3/8, I've been using it the last couple of yrs; 9mm (.354").
Even though I don't thread my ferrules ON, I do run a 9mm tap thru the ferrule.
The tap is always oversize to the drill-size leaving about a .002" deep thrd. on the interior wall.
The reason for that is because the epoxy wicks into the wood better than it does into LBM.

At the end of the day, I don't care how anyone else builds their cues.
They don't build mine and I don't build theirs.
To each his own.

KJ
 
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I dig these threads. Thanks guys!

Oh...and the video is awesome, obviously! :grin:




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