I have a Gitzo G1327 camera tripod with carbon fibre (CF) legs.

The thread at the top of one of the legs where it screws into the
platform(?) head of the tripod has partially stripped and cannot be
tightened. The effect of this is that loosening the twist clamps for
the lower sections of the leg in question turns the leg at the head
end.

Wasting time with Google I have found that most people seem to use
variants of epoxy resin to glue CF to all manner of other stuff
including metal. Is this the case or should I search out some
frightfully expensive specialist adhesive?

The leg can be fully removed from the socket which would allow for
roughening of the mating surfaces of leg and socket.

I do have some JB Weld if that would do a better job that Araldite.

Any tips or solutions would be gratefully received.

Richard

On 17 Oct, 12:22, RJS wrote:

Wasting time with Google I have found that most people seem to use
variants of epoxy resin to glue CF to all manner of other stuff
including metal. * Is this the case or should I search out some
frightfully expensive specialist adhesive?

Epoxy is fine. It's worth seeking out better grades than Araldite
though. West System etc. (try Axminster) sell a thin epoxy that you
thicken as needed with powder or fibre fillers. Mixing before filling
also gives a more reliable mixture. Even model shop epoxies are
better than Araldite, although you pay a hefty premium for small
packages.

Avoid rapid epoxies.

On 17 Oct, 12:36, Andy Dingley wrote:
On 17 Oct, 12:22, RJS wrote:

Wasting time with Google I have found that most people seem to use
variants of epoxy resin to glue CF to all manner of other stuff
including metal. * Is this the case or should I search out some
frightfully expensive specialist adhesive?

Epoxy is fine. *It's worth seeking out better grades than Araldite
though. West System etc. (try Axminster) sell a thin epoxy that you
thicken as needed with powder or fibre fillers. Mixing before filling
also gives a more reliable mixture. *Even model shop epoxies are
better than Araldite, although you pay a hefty premium for small
packages.

Avoid rapid epoxies.

Ta!

RJS wrote:
On 17 Oct, 12:36, Andy wrote:
On 17 Oct, 12:22, wrote:

Wasting time with Google I have found that most people seem to use
variants of epoxy resin to glue CF to all manner of other stuff
including metal. Is this the case or should I search out some
frightfully expensive specialist adhesive?

Epoxy is fine. It's worth seeking out better grades than Araldite
though. West System etc. (try Axminster) sell a thin epoxy that you
thicken as needed with powder or fibre fillers. Mixing before filling
also gives a more reliable mixture. Even model shop epoxies are
better than Araldite, although you pay a hefty premium for small
packages.

Avoid rapid epoxies.

Ta!

Once the glue has set, investigate the possibility of fitting a pin
across the diameter of the tube to add more strength.
A pin such as a section of a nail shank or a broken drill with the end
filed/ground flush would be ideal.

Bob

RJS wrote:
I have a Gitzo G1327 camera tripod with carbon fibre (CF) legs.

The thread at the top of one of the legs where it screws into the
platform(?) head of the tripod has partially stripped and cannot be
tightened. The effect of this is that loosening the twist clamps for
the lower sections of the leg in question turns the leg at the head
end.

Wasting time with Google I have found that most people seem to use
variants of epoxy resin to glue CF to all manner of other stuff
including metal. Is this the case or should I search out some
frightfully expensive specialist adhesive?

The leg can be fully removed from the socket which would allow for
roughening of the mating surfaces of leg and socket.

I do have some JB Weld if that would do a better job that Araldite.


that tends to stick better than epoxy. With epoxy you need to load it a
bit with a filler, clean degrease and scuff the ally, and use moderated
heat to get the epoxy well mixed and runny enough to get into the
aluminium scratches.


Any tips or solutions would be gratefully received.

Richard

On 17 Oct, 13:24, Bob Minchin
wrote:
RJS wrote:
On 17 Oct, 12:36, Andy *wrote:
On 17 Oct, 12:22, *wrote:

Wasting time with Google I have found that most people seem to use
variants of epoxy resin to glue CF to all manner of other stuff
including metal. * Is this the case or should I search out some
frightfully expensive specialist adhesive?

Epoxy is fine. *It's worth seeking out better grades than Araldite
though. West System etc. (try Axminster) sell a thin epoxy that you
thicken as needed with powder or fibre fillers. Mixing before filling
also gives a more reliable mixture. *Even model shop epoxies are
better than Araldite, although you pay a hefty premium for small
packages.

Avoid rapid epoxies.

Ta!

Once the glue has set, investigate the possibility of fitting a pin
across the diameter of the tube to add more strength.
A pin such as a section of a nail shank or a broken drill with the end
filed/ground flush would be ideal.

Bob

Thanks Bob

A pin would be good. Unfortunately the lower sections (2) of the leg
go right to the top of the outer leg when they are collapsed - if that
poor description makes any sense!

Richard

On 17 Oct, 13:39, The Natural Philosopher
wrote:


that tends to stick better than epoxy. With epoxy you need to load it a
bit with a filler, clean degrease and scuff the ally, and use moderated
heat to get the epoxy well mixed and runny enough to get into the
aluminium scratches.

Any tips or solutions would be gratefully received.

Richard

Thanks

I've found that JB Weld is generally better than Araldite - but I've
never used a decent epoxy only ever Araldite.

I've found that JB Weld is very difficult to find.

Richard

On 17 Oct, 12:22, RJS wrote:
I have a Gitzo G1327 camera tripod with carbon fibre (CF) legs.

The thread at the top of one of the legs where it screws into the
platform(?) head of the tripod has partially stripped and cannot be
tightened. The effect of this is that loosening the twist clamps for
the lower sections of the leg in question turns the leg at the head
end.

Wasting time with Google I have found that most people seem to use
variants of epoxy resin to glue CF to all manner of other stuff
including metal. Is this the case or should I search out some
frightfully expensive specialist adhesive?

The leg can be fully removed from the socket which would allow for
roughening of the mating surfaces of leg and socket.

I do have some JB Weld if that would do a better job that Araldite.

Any tips or solutions would be gratefully received.

Richard

gorilla glue?

On 17 Oct, 13:47, RJS wrote:

I've found that JB Weld is very difficult to find.

I've noticed that recently too. I wanted some for its visual
appearance (filling in the buffers on this: http://quercus.livejournal.com/300504.html
) but couldn't find it anywhere across two towns and two cities. Ended
up using silver Milliput instead.

On 17 Oct, 15:21, Andy Dingley wrote:
On 17 Oct, 13:47, RJS wrote:

I've found that JB Weld is very difficult to find.

I've noticed that recently too. I wanted some for its visual
appearance (filling in the buffers on this:http://quercus.livejournal.com/300504.html
) but couldn't find it anywhere across two towns and two cities. Ended
up using silver Milliput instead.

Excellent! However, I've always believed - and tried to ensure it is
so - that the role of an uncle is to enable the nephew/niece to
experience all those things that their parents believe inappropriate
or unsuitable. ;-) Consequently, I'm in fairly high demand with the
small people who all seem undamaged by things such as gruesomely
realistic dinosaur books or stomach-churning fun fairs!

Richard

In message
, RJS
writes
On 17 Oct, 13:39, The Natural Philosopher
wrote:


that tends to stick better than epoxy. With epoxy you need to load it a
bit with a filler, clean degrease and scuff the ally, and use moderated
heat to get the epoxy well mixed and runny enough to get into the
aluminium scratches.

Any tips or solutions would be gratefully received.

Richard

Thanks

I've found that JB Weld is generally better than Araldite - but I've
never used a decent epoxy only ever Araldite.

I've found that JB Weld is very difficult to find.

Does your local car accessory shop not stock it ?

CPC just down the road from you has it

--
geoff

On 17 Oct, 18:35, geoff wrote:
In message
, RJS
writes

On 17 Oct, 13:39, The Natural Philosopher
wrote:

that tends to stick better than epoxy. With epoxy you need to load it a
bit with a filler, clean degrease and scuff the ally, and use moderated
heat to get the epoxy well mixed and runny enough to get into the
aluminium scratches.

Any tips or solutions would be gratefully received.

Richard

Thanks

I've found that JB Weld is generally better than Araldite - but I've
never used a decent epoxy only ever Araldite.

I've found that JB Weld is very difficult to find.

Does your local car accessory shop not stock it ?

CPC just down the road from you has it

--
geoff

Hi Geoff

What did you search the CPC site for? I've plugged 'JB Weld' in and
found nothing. It would be great if I could find a supplier.

By the way, pictures of the tripod can be seen he
http://richard2808.fotopic.net/c1907473.html

Cheers

Richard

On 17 Oct, 12:22, RJS wrote:
I have a Gitzo G1327 camera tripod with carbon fibre (CF) legs.

The thread at the top of one of the legs where it screws into the
platform(?) head of the tripod has partially stripped and cannot be
tightened. *The effect of this is that loosening the twist clamps for
the lower sections of the leg in question turns the leg at the head
end.

Wasting time with Google I have found that most people seem to use
variants of epoxy resin to glue CF to all manner of other stuff
including metal. * Is this the case or should I search out some
frightfully expensive specialist adhesive?

The leg can be fully removed from the socket which would allow for
roughening of the mating surfaces of leg and socket.

I do have some JB Weld if that would do a better job that Araldite.

Any tips or solutions would be gratefully received.

Richard

Carbon fibre is in fact laid up in either epoxy or polyesther resin in
a mould. Ideally would be to use a similar resin as a glue. Epoxy is
the commonest.
The problem with adhesion arises when the finished product has been
polished or has release agents from the mould still on the surface.
If any form of silicone polish/release agent/lubricant has been used
(as is common) repairs are difficult because a bond cannot be
achieved. The silicone gets right into the resin which is in fact
quite porous.
You need to abrade the surface and try. If it fails it's probably for
this reason.

In message
, RJS
writes
On 17 Oct, 18:35, geoff wrote:
In message
, RJS
writes

On 17 Oct, 13:39, The Natural Philosopher
wrote:

that tends to stick better than epoxy. With epoxy you need to load it a
bit with a filler, clean degrease and scuff the ally, and use moderated
heat to get the epoxy well mixed and runny enough to get into the
aluminium scratches.

Any tips or solutions would be gratefully received.

Richard

Thanks

I've found that JB Weld is generally better than Araldite - but I've
never used a decent epoxy only ever Araldite.

I've found that JB Weld is very difficult to find.

Does your local car accessory shop not stock it ?

CPC just down the road from you has it

--
geoff

Hi Geoff

What did you search the CPC site for? I've plugged 'JB Weld' in and
found nothing. It would be great if I could find a supplier.

I didn't search, I've ordered it from there in the past

I was assuming they would still have it

else, I expect I've got some at work, I normally order half a dozen at a
time (JB Quick, though) - I'll check tomorrow


By the way, pictures of the tripod can be seen he
http://richard2808.fotopic.net/c1907473.html

Cheers

Richard

--
geoff

On Sun, 17 Oct 2010 12:10:33 -0700 (PDT), harry
wrote:

Carbon fibre is in fact laid up in either epoxy or polyesther resin in
a mould. Ideally would be to use a similar resin as a glue. Epoxy is
the commonest.
The problem with adhesion arises when the finished product has been
polished or has release agents from the mould still on the surface.
If any form of silicone polish/release agent/lubricant has been used
(as is common) repairs are difficult because a bond cannot be
achieved. The silicone gets right into the resin which is in fact
quite porous.

If the correct release agents have been used then bonding shouldn't
ever be a problem if the joint is correctly cleaned.

Silicones in liquid, wax or spray form, simply aren't used by those
who lay up composites professionally. Semi rigid silicones can very
occasionally be used, these are similar to baking trays / cake / jelly
moulds used in the kitchen.

This is for the simple reason that uncured silicones are really bad
news as their presence can seriously compromise the integrity of the
entire manufacturing process not only in composite sub-assembly but
also when applying paint finishes.

You need to abrade the surface and try. If it fails it's probably for
this reason.

What remains adhered to the composite needs examining. Ideally it
needs removing back to the original finished surface but no further.
flap wheels work quite well for this task. Then a simple degrease is
sufficient.

Aluminium when exposed to the atmosphere almost instantly forms an
oxide surface that reduces the effectiveness of the bonding.

Abrading should therefore be done in an inert atmosphere, for all
practical purposes when working on a repair, a fine scotchbrite pad
should be used for surface preparation. Initially in the air, then
again when below the surface of a suitable solvent degreaser, then
quickly remove the component from the degreaser and wipe with a clean
lint free cloth, then immediately place in a container of catalysed
epoxy and wipe again with a piece of clean scotchbrite pad keeping the
newly abraded surface below the epoxy at all times. Remove and bring
the two parts to be bonded together, maintaining an epoxy covering all
over the bond surface, wiping any excess that exudes from the joint.
Then maintain the parts in alignment, keeping a precise gap between
the parts until the epoxy fully cures.

Of course you could just bang the bits together and forget the
preparation, some 'experts' do just that, and members of the public,
particularly those with more money than sense, experience the failings
of just such an approach every day.


--

In message
, RJS
writes
On 17 Oct, 13:39, The Natural Philosopher
wrote:


that tends to stick better than epoxy. With epoxy you need to load it a
bit with a filler, clean degrease and scuff the ally, and use moderated
heat to get the epoxy well mixed and runny enough to get into the
aluminium scratches.

Any tips or solutions would be gratefully received.

Richard

Thanks

I've found that JB Weld is generally better than Araldite - but I've
never used a decent epoxy only ever Araldite.

I've found that JB Weld is very difficult to find.

I asked my local supplier (car accessory shop) today, he didn't think
that there was any problem getting JB Weld.

If you just want a bit to repair this tripod, I can prolly find a
partially used set

--
geoff

On 18 Oct, 22:51, The Other Mike
wrote:


If the correct release agents have been used then bonding shouldn't
ever be a problem if the joint is correctly cleaned.

Silicones in liquid, wax or spray form, simply aren't used by those
who lay up composites professionally. *Semi rigid silicones can very
occasionally be used, these are similar to baking trays / cake / jelly
moulds used in the kitchen.

This is for the simple reason that uncured silicones are really bad
news as their presence can seriously compromise the integrity of the
entire manufacturing process not only in composite sub-assembly but
also when applying paint finishes.

You need to abrade the surface and try. *If it fails it's probably for
this reason.

What remains adhered to the composite needs examining. Ideally it
needs removing back to the original finished surface but no further.
flap wheels work quite well for this task. *Then a simple degrease is
sufficient.

Aluminium when exposed to the atmosphere almost instantly forms an
oxide surface that reduces the effectiveness of the bonding.

Abrading should therefore be done in an inert atmosphere, for all
practical purposes when working on a repair, a fine scotchbrite pad
should be used for surface preparation. *Initially in the air, then
again when below the surface of a suitable solvent degreaser, then
quickly remove the component from the degreaser and wipe with a clean
lint free cloth, then immediately place in a container of catalysed
epoxy and wipe again with a piece of clean scotchbrite pad keeping the
newly abraded surface below the epoxy at all times. *Remove and bring
the two parts to be bonded together, maintaining an epoxy covering all
over the bond surface, wiping any excess that exudes from the joint.
Then maintain the parts in alignment, keeping a precise gap between
the parts until the epoxy fully cures.

Of course you could just bang the bits together and forget the
preparation, some 'experts' do just that, and members of the public,
particularly those with more money than sense, experience the failings
of just such an approach every day.

--


Can I say 'er blimey'.

But thanks for the in depth solution.

Richard ;-)

On 18 Oct, 22:59, geoff wrote:
In message
, RJS
writes

On 17 Oct, 13:39, The Natural Philosopher
wrote:

that tends to stick better than epoxy. With epoxy you need to load it a
bit with a filler, clean degrease and scuff the ally, and use moderated
heat to get the epoxy well mixed and runny enough to get into the
aluminium scratches.

Any tips or solutions would be gratefully received.

Richard

Thanks

I've found that JB Weld is generally better than Araldite - but I've
never used a decent epoxy only ever Araldite.

I've found that JB Weld is very difficult to find.

I asked my local supplier (car accessory shop) today, he didn't think
that there was any problem getting JB Weld.

If you just want a bit to repair this tripod, I can prolly find a
partially used set

--
geoff

Thanks Geoff

That's very kind. However, I do have some JB Weld and make a point of
buying it whenever I see it - which hasn't been for a couple of years.

Regards

Richard

On 19 Oct, 20:56, RJS wrote:
On 18 Oct, 22:51, The Other Mike
wrote:











If the correct release agents have been used then bonding shouldn't
ever be a problem if the joint is correctly cleaned.

Silicones in liquid, wax or spray form, simply aren't used by those
who lay up composites professionally. *Semi rigid silicones can very
occasionally be used, these are similar to baking trays / cake / jelly
moulds used in the kitchen.

This is for the simple reason that uncured silicones are really bad
news as their presence can seriously compromise the integrity of the
entire manufacturing process not only in composite sub-assembly but
also when applying paint finishes.

You need to abrade the surface and try. *If it fails it's probably for
this reason.

What remains adhered to the composite needs examining. Ideally it
needs removing back to the original finished surface but no further.
flap wheels work quite well for this task. *Then a simple degrease is
sufficient.

Aluminium when exposed to the atmosphere almost instantly forms an
oxide surface that reduces the effectiveness of the bonding.

Abrading should therefore be done in an inert atmosphere, for all
practical purposes when working on a repair, a fine scotchbrite pad
should be used for surface preparation. *Initially in the air, then
again when below the surface of a suitable solvent degreaser, then
quickly remove the component from the degreaser and wipe with a clean
lint free cloth, then immediately place in a container of catalysed
epoxy and wipe again with a piece of clean scotchbrite pad keeping the
newly abraded surface below the epoxy at all times. *Remove and bring
the two parts to be bonded together, maintaining an epoxy covering all
over the bond surface, wiping any excess that exudes from the joint.
Then maintain the parts in alignment, keeping a precise gap between
the parts until the epoxy fully cures.

Of course you could just bang the bits together and forget the
preparation, some 'experts' do just that, and members of the public,
particularly those with more money than sense, experience the failings
of just such an approach every day.

--

Can I say 'er blimey'.

But thanks for the in depth solution.

Richard *;-)

Ditto - and it does explain why I've had Al joints fail despite
cleaning, abrading, etc. Interestingly I have not had a failure with
PU glue on Al joints, admittedly in low stress situations.

What does a 'precise gap' mean; do it take it that firm clamping is
also not recommended ? Are you suggesting that the bond layer should
have minimum thickness and not a minimal thickness ?

Rob

On Wed, 20 Oct 2010 12:34:28 -0700 (PDT), robgraham
wrote:

Ditto - and it does explain why I've had Al joints fail despite
cleaning, abrading, etc. Interestingly I have not had a failure with
PU glue on Al joints, admittedly in low stress situations.

What does a 'precise gap' mean; do it take it that firm clamping is
also not recommended ? Are you suggesting that the bond layer should
have minimum thickness and not a minimal thickness ?

Clamping is good but you need to maintain a certain thickness in the
glue line whilst keeping the parts concentric or spaced by a certain
distance depending on the adhesive used. This ought to be engineered
into the design of the joint but often isn't.

A typical epoxy, and indeed some polyurethanes ideally require a joint
gap of around 0.05 - 0.2 mm or about 2 - 8 thousandths of an inch.
With some consumer products, and with repairs you'll often have much
bigger gaps than that and hence more reliance on the gap filling
properties and thus a greater tendency for joint failure.

When joining two flat surfaces thin shims would be fixed in a grid
pattern to the surface with appropriately distributed clamping in
order that a consistent glue line is maintained.

On circular parts you would ideally have a recess in one or both of
the parts such that there was almost full annular contact between the
two parts you were joining (and thus almost no glue) whilst in the
recess would be the glue that joined the two parts together. Vent
paths for air and glue are then needed when assembling these tightly
fitting joints.

Fitting pins across the joint to lock the two parts together is a
bodge that really isn't needed unless required for fail safe purposes.



--