Repairing carbon fiber - adhesive recommendations?

On Friday, December 6, 2019 at 12:37:41 PM UTC-5, Neil wrote:
On 12/6/2019 9:10 AM, Alan Browne wrote:
On 2019-12-04 14:41, Neil wrote:
On 12/4/2019 11:22 AM, -hh wrote:
On Wednesday, December 4, 2019 at 11:09:44 AM UTC-5, Davoud wrote:
hh:

Just back from a trip where I had the unplanned experience of my
Gitzo carbon fiber tripod come apart on me.

You wouldn’t consider contacting Gitzo for a repair before gumming
it up to the point where they won’t even look at it?

Not really.Â* Its an older model (no warranty) and Gitzo repair
services doesn't have a particularly good reputation:Â* I'd rather
not be without the tripod for ~6 months.

FYI, the recommended cleaner appears to be denatured alcohol and
if one goes with 2-part epoxy, the recommendation is to avoid
the fast-set stuff because of heat generated; go with 24hr.

I agree with the 2-part epoxy. It will adhere to most materials and
provide good strength once it has set.

I don't know how important it would be to remove the existing residue,
since the epoxy may dissolve the residue while it sets.

Epoxy doesn't dissolve much, if anything.Â* It's always best to have
surfaces that are as clean as possible.Â* If they are very smooth, you
can 'rough' them up to improve bonding.Â* With carbon fibre breaks it's
usually more than rough enough.

As a read the OP's message, it didn't come across as a break, but a
disassembly of the leg and head mount. -hh wrote:

"The failure location is near the top of the tripod, between the top
interface plate and the top of the center column tube.

"The (now revealed) bottom of the interface plate is like a plug that
slides down inside the ID of the center column tube. Looks like it was
a glue failure. FYI these two parts are also both keyed. This is
intended to carry the torsion forces of screwing down a ball head so as
to minimize forces being imparted on the glue joint itself."

Correct: there was no break of a CF tube, but was that the metal
assembly which slips into the ID of the tube had its glue joint failure.


If so, the likely adhesive is epoxy, and the application of
2-part epoxy would probably dissolve the original. If it didn't
it wouldn't matter because the parts would bond anyway.

I've appreciated the comments.

My plan is to clean everything with a suitable solvent - It looks
like Methyl Hydrate (wood alcohol) is slightly favored?; not
sure if I happen to already have some in stock (if its
the same product as "Denatured Alcohol", then yes), with the
backup choices being Acetone and Isopropyl Alcohol.

I might try a few solvents (sequentially) to see about
removing (most of) the existing glue's residue, because bonding
strength often depends on getting the bond thickness correct.

From there, I'll be using a 24 2-part epoxy, and clamp it all
down for 24-48 hours while in a warm, dry space for curing.

FYI, I found an interesting list he
https://dragonplate.com/adhesives-applicators

Which has some interesting products; thinking the 3M Scotch-Weld
Epoxy 2216, unless a metal-filled such as the DP420 is merited.



-hh

On 06/12/2019 00:44, RichA wrote:


Acetone will dissolve the surface even more. Methyl Hydrate (100% wood alcohol) is the best cleaner. You can buy it in a hardware store.

I'm not sure which "surface" you are referring to. Acetone attacks a
number of polymers, but even in those cases *wiping* with acetone is a
good way to get a clean surface that epoxy or cyanoacrylate will bond to.

It may damage the finish of something that originally looked nice.

Carbon fiber is held together with epoxy. Acetone will dissolve it, thought it likely wouldn't do more than mar the surface if used as a wipe. Just don't use it long.

Agreed. It doesn't attack it all that quickly and I was only talking
about a wipe over the bit to be glued.

On 12/6/2019 1:31 PM, -hh wrote:
On Friday, December 6, 2019 at 12:37:41 PM UTC-5, Neil wrote:
On 12/6/2019 9:10 AM, Alan Browne wrote:
On 2019-12-04 14:41, Neil wrote:
On 12/4/2019 11:22 AM, -hh wrote:
On Wednesday, December 4, 2019 at 11:09:44 AM UTC-5, Davoud wrote:
hh:

Just back from a trip where I had the unplanned experience of my
Gitzo carbon fiber tripod come apart on me.

You wouldn’t consider contacting Gitzo for a repair before gumming
it up to the point where they won’t even look at it?

Not really.Â* Its an older model (no warranty) and Gitzo repair
services doesn't have a particularly good reputation:Â* I'd rather
not be without the tripod for ~6 months.

FYI, the recommended cleaner appears to be denatured alcohol and
if one goes with 2-part epoxy, the recommendation is to avoid
the fast-set stuff because of heat generated; go with 24hr.

I agree with the 2-part epoxy. It will adhere to most materials and
provide good strength once it has set.

I don't know how important it would be to remove the existing residue,
since the epoxy may dissolve the residue while it sets.

Epoxy doesn't dissolve much, if anything.Â* It's always best to have
surfaces that are as clean as possible.Â* If they are very smooth, you
can 'rough' them up to improve bonding.Â* With carbon fibre breaks it's
usually more than rough enough.

As a read the OP's message, it didn't come across as a break, but a
disassembly of the leg and head mount. -hh wrote:

"The failure location is near the top of the tripod, between the top
interface plate and the top of the center column tube.

"The (now revealed) bottom of the interface plate is like a plug that
slides down inside the ID of the center column tube. Looks like it was
a glue failure. FYI these two parts are also both keyed. This is
intended to carry the torsion forces of screwing down a ball head so as
to minimize forces being imparted on the glue joint itself."

Correct: there was no break of a CF tube, but was that the metal
assembly which slips into the ID of the tube had its glue joint failure.


If so, the likely adhesive is epoxy, and the application of
2-part epoxy would probably dissolve the original. If it didn't
it wouldn't matter because the parts would bond anyway.

I've appreciated the comments.

My plan is to clean everything with a suitable solvent - It looks
like Methyl Hydrate (wood alcohol) is slightly favored?; not
sure if I happen to already have some in stock (if its
the same product as "Denatured Alcohol", then yes), with the
backup choices being Acetone and Isopropyl Alcohol.

I might try a few solvents (sequentially) to see about
removing (most of) the existing glue's residue, because bonding
strength often depends on getting the bond thickness correct.

From there, I'll be using a 24 2-part epoxy, and clamp it all
down for 24-48 hours while in a warm, dry space for curing.

FYI, I found an interesting list he
https://dragonplate.com/adhesives-applicators

Which has some interesting products; thinking the 3M Scotch-Weld
Epoxy 2216, unless a metal-filled such as the DP420 is merited.

Much of this may be overkill. You won't need a lot of epoxy to fix this,
and a product like JB Weld is easy to use, inexpensive (under $5.00US at
the hardware store I purchased it from), and has strength of over 3,000
lbs PSI.

https://www.jbweld.com/product/clearweld-syringe

If the parts fit together with the residue, I'd glue it and move on.

--
best regards,

Neil

Davoud:
I was unaware of Gitzo's bad reputation in repairs. Can you
cite a source for this information?

-hh
Noticed the pattern in some basic internet searches:

"After trying to get parts from the US Gitzo source, only to be
told of long delays, I found an alternative that actually stocks
most things."

https://www.fredmiranda.com/forum/topic/1036151

"Gitzo repair 1-1/2 months?"

"Sent it in for service under warranty in March....Received it
back fixed in August."

https://www.dpreview.com/forums/thread/4017780

-hh

OK, noted, though two instances don’t make a pattern. My take-away is,
don’t beat up your tripod. I have Gitzos that are many years old—older
than I can remember—and I’ve never had a problem.

On Friday, December 6, 2019 at 7:15:08 PM UTC-5, Davoud wrote:
Davoud:
I was unaware of Gitzo's bad reputation in repairs. Can you
cite a source for this information?

-hh
Noticed the pattern in some basic internet searches:

"After trying to get parts from the US Gitzo source, only to be
told of long delays, I found an alternative that actually stocks
most things."

https://www.fredmiranda.com/forum/topic/1036151

"Gitzo repair 1-1/2 months?"

"Sent it in for service under warranty in March....Received it
back fixed in August."

https://www.dpreview.com/forums/thread/4017780

-hh

OK, noted, though two instances don’t make a pattern.

I only bothered to cite two examples...but believe what you want.


My take-away is, don’t beat up your tripod.

Thanks for the malicious insinuation; it really helps your reputation.


I have Gitzos that are many years old—older
than I can remember—and I’ve never had a problem.

Other than this glue joint separation, this particular tripod is
still in EX+ shape, as it has never been "abused".


-hh

On 2019-12-06 12:37, Neil wrote:

If so, the likely adhesive is epoxy, and the application of 2-part epoxy
would probably dissolve the original. If it didn't it wouldn't matter
because the parts would bond anyway.

Epoxy is not a solvent. If you mean it would encapsulate residue, then
fine, but that's just shoddy workmanship.

On 12/7/2019 9:58 AM, Alan Browne wrote:
On 2019-12-06 12:37, Neil wrote:

If so, the likely adhesive is epoxy, and the application of 2-part
epoxy would probably dissolve the original. If it didn't it wouldn't
matter because the parts would bond anyway.

Epoxy is not a solvent.Â* If you mean it would encapsulate residue, then
fine, but that's just shoddy workmanship.

The shoddy workmanship of Gitzo is why this discussion exists. Waste as
much of your time as you wish correcting their poor construction.
Perhaps disassemble the entire tripod and make it as it should have been
in the first place. Shouldn't take you more than a week or so.

The repair I suggested will be permanent, so I'd rather spend my time
using the tripod than rebuilding it.

--
best regards,

Neil

On 2019-12-07 15:17, Neil wrote:
On 12/7/2019 9:58 AM, Alan Browne wrote:
On 2019-12-06 12:37, Neil wrote:

If so, the likely adhesive is epoxy, and the application of 2-part
epoxy would probably dissolve the original. If it didn't it wouldn't
matter because the parts would bond anyway.

Epoxy is not a solvent.Â* If you mean it would encapsulate residue,
then fine, but that's just shoddy workmanship.

The shoddy workmanship of Gitzo is why this discussion exists. Waste as
much of your time as you


.... not following the thread very well, huh?