In stead of glue "escape" holes / grooves

Newton

Newton

AzB Silver Member
Silver Member
Using my DRO I'm fond of making stuff ultra tight (not so tight as you split things...) when joining parts and installing pins.
I know some of you use glue releafe (correct spelled?) holes or use a saw to make a escape path along the threads/hole.

I just had a thought, in stead why not use a really small coring drill-like 3-4mm and core either a section of the handle or potentially the whole part?
Glue could escape inside the part and we could make things to tight tolerances.

I'm currently repairing 2 cues which one was broken under the jointcollar and the other has a bullet joint with no threads left in the cue.
Making a new inside tennon, threading and coring with a small drill is my plan.

Stupid idea or is it something obvious which you all do?

K
 
Having a cavity in the bottom of a hole is fine for a reservoir to catch excess glue, but it'll make no difference with internal pressure. With a tight fit, you compress the air inside the cavity. Once compressed enough, it'll blow out the sides of the wood. Even if the air escapes but it's still a tight fit, the liquid glue will not compress, so naturally the wood will split to allow relief. Worst case scenario is the cavity full of compressed air but doesn't crack, and you send the cue out. Every time the cue hits a ball it's like jabbing at a balloon. Eventually, it'll pop.

The glue relief grooves don't reduce tolerances of fit. The component still fits the same. The grooves allows the air and excess glue to escape without causing the compressed air cavity.
 
Good points Qbuilder.
I'm going to core the whole part so air and glue could escape from the cavity. At the moment it's like pulling out a cork from a bottle when test fitting which makes me reluctant to fill the cavity with epoxy and "go for it":-)
Covering up the escape hole with a inlay is something I'm not fund of but I'll have a test run and see how it goes:-)
Thanks for your feedback.
K
 
It's still a similar to what we discussed before. Like Eric said It's still gonna build pressure. Think of It as a Hydraulic system, only that when compared to steel lines or hoses, when wood expands It can split or blow out much easier. Regardless of whether you provide for glue relief or not, and You screw the piece in faster then the pressure can be released, the higher the risk of a blowout. The core is basically a piston only with out the rings, and a much thicker fluid so the compression if very high and somewhat more sustained.

I mentioned to You before that on some pins I can get away with not cutting a groove, by using a slow set epoxy, and screwing the pin in at intervals giving time in between for the pressure to relieve, so never building up pressure to begin with, but that is a different situation then what your about to do here. I would definitely recommend providing for glue relief, because the side walls are gonna be much thinner, and the larger plug will create more compression. The risk of over doing It by accident, or trapping air behind the plug are much higher.


Greg
 
Greg,
We agree for sure on the pin install as discussed earlier.

Now my point is that coring with a small diameter - all the way- would be the "escape" for both glue and air. I was just wondering if this was worth considering in stead of the other ways we do these things.

I was thinking " what if the glue don't fill the core?"
Would this affect the hit?

Regarding pin-how if we got these not just with a center drilled hole but fully cored so glue and air could get out without problems?

Thanks for the feedback
K
 
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Newton said:
Greg,
We agree for sure on the pin install as discussed earlier.

Now my point is that coring with a small diameter - all the way- would be the "escape" for both glue and air. I was just wondering if this was worth considering in stead of the other ways we do these things.

I was thinking " what if the glue don't fill the core?"
Would this affect the hit?

Regarding pin-how if we got these not just with a center drilled hole but fully cored so glue and air could get out without problems?

Thanks for the feedback
K
Click to expand...

I don't know how It would hit, who knows, You may be on to a low deflection joint or something there :thumbup:, but I'm like you. I like tight fits, so I probably would not want the cavity there.

If what You are referring to is drilling all the way through the core where the pin would eventually be, then I don't see where that could not work to relieve pressure too, so yes you should be fine that way. If you were to run into any trouble at all I would think That would only come into play when installing the pin, and that would only depend on several circumstances. Like the hole not being straight and using a less then appropriate drill bit, but If You used the right bit, reamer, or even better yet bore the hole for your pin then There should not even be an issue with that. It would leave you with a cleaner looking joint face in the end,because you would not see the end of the glue grooves. I assume that's the reasoning behind what Your thinking.

Yes, a Hole through the center of the pin may help if large enough to account for the given viscosity of the glue, but I would imagine that the larger the hole is the weaker the pin would be.

Greg
 
glue relief

without filling the relief hole solidly you could risk a ringing sound during play with the cue.there could be the glue come loose in the hole and rattle(seen this in early predators,and it is amplified in a cue).
 
You ever wonder why a balloon won't stay inflated for more than a day or two?
Two days after the party, the balloon is about 1/2 it's original size.
Where did the air go???
Was the knot not tight enough???

The air molecules migrated through the skin of the balloon.
Wood won't confine it for any length of time either.
Wood makes for a lousy inner-tube.
Your concern for the compressed air is only valid while installing the pin.
It quickly dissipates.
You can compress air, you can't compress a liquid.
Food for thought.

KJ
 
KJ Cues said:
You ever wonder why a balloon won't stay inflated for more than a day or two?
Two days after the party, the balloon is about 1/2 it's original size.
Where did the air go???
Was the knot not tight enough???

The air molecules migrated through the skin of the balloon.
Wood won't confine it for any length of time either.
Wood makes for a lousy inner-tube.
Your concern for the compressed air is only valid while installing the pin.
It quickly dissipates.
You can compress air, you can't compress a liquid.
Food for thought.

KJ
Click to expand...


You make a good point, and looking at from that angle I doubt wood alone could trap It, and hold It. What about the epoxy? I mean we have all seen the remnants of air in epoxy in the form of a bubble, Could It work to seal the air in if it cured before escaping, or does It eventually migrate through that like It would the balloon or wood, and all your seeing is an empty cavity left behind?

Greg
 
KJ Cues said:
You ever wonder why a balloon won't stay inflated for more than a day or two?
Two days after the party, the balloon is about 1/2 it's original size.
Where did the air go???
Was the knot not tight enough???

The air molecules migrated through the skin of the balloon.
Wood won't confine it for any length of time either.
Wood makes for a lousy inner-tube.
Your concern for the compressed air is only valid while installing the pin.
It quickly dissipates.
You can compress air, you can't compress a liquid.
Food for thought.

KJ
Click to expand...

Wood may not hold air, but epoxy sure will.
 
Wasn't there a video on plugging escape holes with paper tissue then let the epoxy penetrate that paper tissue ?
Glue channels, straight or spiral work for me.
 
Walid point KJ.
I'm not that concerned about the air-it's just to take your time.
Was just wondering if the idea was any usefull since I feel some times the glue scare me..
Have been in the workshop all day and might shoot some pics of those repairs and show how it goes.
I was afraid that the glue could cause ratling sound after some years-but I'll give it a try since these cues has been considered "write offs" by the owners.

Thought maybe some one had done this but maybe not...

K
 
glue relief

you could also use some spray insulating foam to fill the hole and elimanate any possibilities of some glue getting loose and rattling.
 
Gluing the glue huh? Interesting approach.



Kent,
The concept of a relief-hole that you speak of is already being done by more than one that I know of.
We have a CM up this way in Michigan, east-side of Detroit I believe, by the name of
Mike Pancerny (hope I didn't botch your name too badly) that drills a glue-relief hole
in the side of the forearm near the bottom of the pin. He makes no effort to hide it.
IIRC, he uses it as evidence to the fact that all the air is pushed out of the cavity.
A selling point as well.

As fate would have it, I've been doing some re-wraps on a few new Schons lately.
Guess what??? Glue-relief hole in the under-wrap area. Purpose: evacuating the 'A' jnt.
I've wrapped a lot of Schons and just recently is when I've noticed it.

MORE FOOD
We've all heard that 'Nature abhors a vacuum'(absence of air).
Well, she's not too fond of air being under pressure either.
Both are considered abominations of Nature. Nature seeks balance and equilibrium.
The air molecule is considerably smaller than that of epoxy.
If there's a way out of the cavity, the air will find it and the epoxy won't stop it.
Please consider that this is happening while the epoxy is still in liquid form.
The trapped air will continue to escape until it reaches EQUILIBRIUM with the air
outside the cavity (outside of the cue). Once that happens, the air will stop moving.
Every epoxied joint will contain air. There's air in the epoxy from being mixed.
It's just a matter of degree.

When you split a forearm from hydraulic pressure, it's not the air that caused the split.
It was either too much glue in the hole or from advancing the piston/screw too quickly.
Sometimes it's because you've allowed the epoxy to get too thick.

I mill a glue-relief into the side of my pin and I install my pins by hand.
After you've split a F/A or two you get a sense of just how much pressure/speed you can
get away with.

KJ
 
glue relief

KJ said it best,after a while doing this stuff you get a feel for what works best for yourself,we all have our technics,only time and our customers can tell what's better,thats why the big money is going to the guys that have been doing this for 25 yrs..i'm halfway,still expermenting,still wasting money.
 
Sure, wood isn't air tight, but where is that air going to go? How much will find itself trapped just under the finish causing the finish to lift. I think standard practices ARE standard practices for a reason.
 
KJ Cues said:
Gluing the glue huh? Interesting approach.



Kent,
The concept of a relief-hole that you speak of is already being done by more than one that I know of.
We have a CM up this way in Michigan, east-side of Detroit I believe, by the name of
Mike Pancerny (hope I didn't botch your name too badly) that drills a glue-relief hole
in the side of the forearm near the bottom of the pin. He makes no effort to hide it.
IIRC, he uses it as evidence to the fact that all the air is pushed out of the cavity.
A selling point as well.

As fate would have it, I've been doing some re-wraps on a few new Schons lately.
Guess what??? Glue-relief hole in the under-wrap area. Purpose: evacuating the 'A' jnt.
I've wrapped a lot of Schons and just recently is when I've noticed it.

MORE FOOD
We've all heard that 'Nature abhors a vacuum'(absence of air).
Well, she's not too fond of air being under pressure either.
Both are considered abominations of Nature. Nature seeks balance and equilibrium.
The air molecule is considerably smaller than that of epoxy.
If there's a way out of the cavity, the air will find it and the epoxy won't stop it.
Please consider that this is happening while the epoxy is still in liquid form.
The trapped air will continue to escape until it reaches EQUILIBRIUM with the air
outside the cavity (outside of the cue). Once that happens, the air will stop moving.
Every epoxied joint will contain air. There's air in the epoxy from being mixed.
It's just a matter of degree.

When you split a forearm from hydraulic pressure, it's not the air that caused the split.
It was either too much glue in the hole or from advancing the piston/screw too quickly.
Sometimes it's because you've allowed the epoxy to get too thick.

I mill a glue-relief into the side of my pin and I install my pins by hand.
After you've split a F/A or two you get a sense of just how much pressure/speed you can
get away with.

KJ
Click to expand...

I like your idea of hiding the relief hole under the wrap, that makes it covered all the time.
In case there would be a repair, the hole could be reused and no problems occur.
However hiding this under some inlays or rings is not my thing. A fellow repair man blew a cues rings while installing the pin. I think this was due to using to thick glue and not taking his time - however if the hole was under some inlays or something it would blow that out if he was unlucky.

I think I would try this idea out using a small drill to core the handles/forarm so these things would be taken care of this way. I'm not saying normal practice is not good enough - it was just a new though I had which I just wanted to air for you guys.

Thanks for all the feedbacks and I'll do a test run to see how this work out.
K
 
Newton said:
I like your idea of hiding the relief hole under the wrap, that makes it covered all the time.
In case there would be a repair, the hole could be reused and no problems occur.
However hiding this under some inlays or rings is not my thing. A fellow repair man blew a cues rings while installing the pin. I think this was due to using to thick glue and not taking his time - however if the hole was under some inlays or something it would blow that out if he was unlucky.

I think I would try this idea out using a small drill to core the handles/forarm so these things would be taken care of this way. I'm not saying normal practice is not good enough - it was just a new though I had which I just wanted to air for you guys.

Thanks for all the feedbacks and I'll do a test run to see how this work out.
K
Click to expand...
Fwiw when I want air tight threaded and capped ferrules, I apply super on the glue hole and then put a tape on top. When the epoxy pressure gets too much, that superglue and tape would pop out.
 
Lexicologist71 said:
Sure, wood isn't air tight, but where is that air going to go? How much will find itself trapped just under the finish causing the finish to lift. I think standard practices ARE standard practices for a reason.
Click to expand...

Rather than turning this into a Physics-101 class, let me offer an analogy that should
help you see this concept a little clearer.
I don't know how much experience you've had with auto-clear but anyone who has is aware
of a condition known as 'pinch-down'. This is when the clear will pinch-down or contract
onto the surface it's applied to. It's millage/thickness will be reduced.
What's happening is that the clear is giving-up residual components that were in the clear when it
was a liquid, solvents & such (nasty gases). It does this over an extended period of time.
Well, my point of this is that they are traveling through solid clear to get to the
surface to evaporate. They don't just come from the top surface of the finish, they come
from the bottom as well. Simply stated, it's molecules in motion. Pretty neat huh?

Now to your concern of air being trapped under the finish, there's already air under the finish, moisture too.
Cues breath. They take air & moisture in and let them out given their environment.
Another way to look at is wet air vs dry air.
I'd think it would have to be something pretty extreme to affect the finish.

I just did a quick calc. to see just how much volume of air we're talking about here
and it turns out to be roughly .04 cu. in. Trust me, I was very generous with the numbers.
How much pressure that little 4/100 of a cu.in. is under, I have no way of knowing.
As the cue breathes, the pressure within that cavity will eventually become equal to the air-pressure outside of the cue.

This I don't believe I quite understand:
"I think standard practices ARE standard practices for a reason."
Seriously, if you could now allow me a better understanding of your meaning of this
statement, it would be appreciated.

KJ
 
Drilling a hole into the side of the cue for glue relief has been done by many through the years. A hollow joint pin has also been done. The hollow joint pin works fine on butt/shaft joints, but not so well on handle/forearm-joints. The reason is it only relieves the pressure in the threaded hole and does not relieve the pressure where the tenon is. So slots or looser fits seems to be the best way to go. Covering a pin size hole up in the forearm or handle might not be too hard to inlay over, but those who have done it at the cue joint area have had a much harder time figuring out what to do about it.
The hollow pin and glue relief hole both have another negative I can see. They would let out glue the pressure too soon in the process and may not give full glue contact around the threads. Half glued threads would be begging for noises and buzzes. So I am still convinced a little looser fit with the right thickness of glue or slots or both is the better method.
 
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