JRG
New Member
I am repairing the wooden center board of a GP14 which has split along a glued joint. It has lasted for 39 years. Any suggestions as to which glue would be the best to use for this purpose?
What glue?
- Thread starter JRG
- Start date
AIDY
Well-Known Member
guernseyman
Well-Known Member
If the board is rigid, Araldite should work. It is waterproof.
pheran
Well-Known Member
39 years ago Cascamite was probably THE adhesive of choice for wooden boat builders. Waterproof and immensely strong, still in use today and has improved even further over the years. Stick the name into Google for a description and list of suppliers.
JRG
New Member
Many thanks all. Cascamite would be my glue of choice which is now called Extramite. I also wondered about Balcotan. I was looking for somewhere which has reviewed marine glues. Does such a site exist?
VicS
Well-Known Member
Cascamite never worked for me. Aeriloite 306 is what I used for all my dinghy building and is I belive still available.
Polyurethane adhesives have appeared since I last did any of that sort of woodwork. You should check them out.
A water proof PVA glue might even be adequate for your needs. Readily available and easy to use.
Polyurethane adhesives have appeared since I last did any of that sort of woodwork. You should check them out.
A water proof PVA glue might even be adequate for your needs. Readily available and easy to use.
NigeCh
Well-Known Member
Cascamite/Extramite failure
Ignore the instructions - 1) Check the batch number/expiry date - Cascamite/Extramite is VERY date sensitive!!! /forums/images/graemlins/frown.gif((( Make sure that the air temp is above 15C; 2) Mix with just enough water till it just goes from thixotropic to liquid ....
BTW, I always thought that Cascamite and Aerolite 306 were the same thing ????
K
Ignore the instructions - 1) Check the batch number/expiry date - Cascamite/Extramite is VERY date sensitive!!! /forums/images/graemlins/frown.gif((( Make sure that the air temp is above 15C; 2) Mix with just enough water till it just goes from thixotropic to liquid ....
BTW, I always thought that Cascamite and Aerolite 306 were the same thing ????
K
VicS
Well-Known Member
Re: Cascamite/Extramite failure
[ QUOTE ]
BTW, I always thought that Cascamite and Aerolite 306 were the same thing ????
[/ QUOTE ] Yes they are both urea formaldehyde glues but Aerolite 306 is a two part one. You apply the hardener (formic acid) to one surface and the adhesive to the other. The mixed adhesive will keep for several days which is useful with on going jobs whereas the single pack Cascamite won't. The shelf life is probably longer as well
I just had better results with the Aerolite than I ever did with Cascamite.
Cascophen, now called Extramite, is a phenol formaldehyde glue with better water resistance than urea formaldehydes.
Another is resorcinol formaldehyde such as Aerodux 500. I think that has even better water resistance and is slower setting.
[ QUOTE ]
BTW, I always thought that Cascamite and Aerolite 306 were the same thing ????
[/ QUOTE ] Yes they are both urea formaldehyde glues but Aerolite 306 is a two part one. You apply the hardener (formic acid) to one surface and the adhesive to the other. The mixed adhesive will keep for several days which is useful with on going jobs whereas the single pack Cascamite won't. The shelf life is probably longer as well
I just had better results with the Aerolite than I ever did with Cascamite.
Cascophen, now called Extramite, is a phenol formaldehyde glue with better water resistance than urea formaldehydes.
Another is resorcinol formaldehyde such as Aerodux 500. I think that has even better water resistance and is slower setting.
old_salt
Well-Known Member
Balcotan is an excellent one part glue just make sure that all the mating surfaces are a close fit with no large gaps. Max gap I would say is about 1 mm = .040 ins.
Give the man a call he is well clued up.
Melco Bonding Supplies
Fiddlers Green, Shop Lane.Conglton. Cheshire.
tel:- 01260-276997
Give the man a call he is well clued up.
Melco Bonding Supplies
Fiddlers Green, Shop Lane.Conglton. Cheshire.
tel:- 01260-276997
misterg
Well-Known Member
Another Cascamite-phobe. Glued up a really difficult job with this, years ago, only for the glue to crystalise like sugar and everything fall apart /forums/images/graemlins/mad.gif
Aerolite 306 was never a problem - kept for years, easy to mix & apply, etc. etc.
I suspect both of these have been replaced by polyurethane (Balcotan, etc.) for this sort of job. Various flavours available from Builder's Merchants. Most will fill gaps and works on slightly damp wood, too. Takes days to get it off your skin, though.
Personally, I wouldn't use PVA, as I've never been convinced that it is properly waterproof, or that it doesn't 'creep' under stress (or maybe my joints just weren't good enough...)
Epoxy if you're rich and the wood is dry??
Andy
Aerolite 306 was never a problem - kept for years, easy to mix & apply, etc. etc.
I suspect both of these have been replaced by polyurethane (Balcotan, etc.) for this sort of job. Various flavours available from Builder's Merchants. Most will fill gaps and works on slightly damp wood, too. Takes days to get it off your skin, though.
Personally, I wouldn't use PVA, as I've never been convinced that it is properly waterproof, or that it doesn't 'creep' under stress (or maybe my joints just weren't good enough...)
Epoxy if you're rich and the wood is dry??
Andy
VicS
Well-Known Member
[ QUOTE ]
Personally, I wouldn't use PVA, as I've never been convinced that it is properly waterproof, or that it doesn't 'creep' under stress
[/ QUOTE ] I think it is best described as "water resistant" so should be Ok for something made wet intermittently. I also assume that the job in question will be screwed or nailed as well.
Personally, I wouldn't use PVA, as I've never been convinced that it is properly waterproof, or that it doesn't 'creep' under stress
[/ QUOTE ] I think it is best described as "water resistant" so should be Ok for something made wet intermittently. I also assume that the job in question will be screwed or nailed as well.
oldsaltoz
Well-Known Member
G'day Clifferd, and welcome to the YBW forums, this being your second post; no doubt many more to come.
To repair the centre board I would use an epoxy resin mixed with some Micro-Fibres, this stuff is very strong, very water resistant and very easy to use.
Just make sure the timber is completely dry first, them mix a very small batch of resin and hardener, then add some methylated spirits (Up to 40% by volume), this will give you a thin penetrating coat that soaks into the timber and adds strength to the bond, just keep dabbing it on till it will take no more, then wait for it to go tacky and mix more resin and hardener then add Micro-Fibres till it's about as thick as toothpaste, apply this to the joint and very lightly clamp it; don't be temped to squeeze out all the resin.
Let it cure for 24 hours, then wipe with a solvent to remove any residue (Acetone is good) then sand to shape, ready to paint or varnish.
Avagoodweekend......
To repair the centre board I would use an epoxy resin mixed with some Micro-Fibres, this stuff is very strong, very water resistant and very easy to use.
Just make sure the timber is completely dry first, them mix a very small batch of resin and hardener, then add some methylated spirits (Up to 40% by volume), this will give you a thin penetrating coat that soaks into the timber and adds strength to the bond, just keep dabbing it on till it will take no more, then wait for it to go tacky and mix more resin and hardener then add Micro-Fibres till it's about as thick as toothpaste, apply this to the joint and very lightly clamp it; don't be temped to squeeze out all the resin.
Let it cure for 24 hours, then wipe with a solvent to remove any residue (Acetone is good) then sand to shape, ready to paint or varnish.
Avagoodweekend......
JRG
New Member
Thanks to all for your comments. At present I am leaning towards aerolite 306. The joint in the board is w shaped and was probably bonded with cascamite as there is evidence of crystalization along the joint which may partly explain why it split open. At the time we were half a mile out to sea and about to enjoy a lively sail.
VicS
Well-Known Member
What ever you use clean off all the old glue or the new joint will be no stronger that that at best. I like to roughen the surfaces to be glued at little. Lightly score across the grain with some coarse-ish sand paper if you can
PuffTheMagicDragon
Well-Known Member
Re: Cascamite/Extramite failure
[ QUOTE ]
Cascophen, now called Extramite, is a phenol formaldehyde glue with better water resistance than urea formaldehydes.
Another is resorcinol formaldehyde such as Aerodux 500. I think that has even better water resistance and is slower setting.
[/ QUOTE ]
I have always used Cascophen with excellent results, e.g. laminated keel on a wooden boat, i.e. continuously immersed in sea water.
Funny thing is that I have always firmly believed that I was using a resorcinol adhesive!
Isn't it the dark <span style="color
urple"> purple </span> syrup that is mixed with a powder hardener in the ratio of 5:1 ?
[ QUOTE ]
Cascophen, now called Extramite, is a phenol formaldehyde glue with better water resistance than urea formaldehydes.
Another is resorcinol formaldehyde such as Aerodux 500. I think that has even better water resistance and is slower setting.
[/ QUOTE ]
I have always used Cascophen with excellent results, e.g. laminated keel on a wooden boat, i.e. continuously immersed in sea water.
Funny thing is that I have always firmly believed that I was using a resorcinol adhesive!
Isn't it the dark <span style="color
urple"> purple </span> syrup that is mixed with a powder hardener in the ratio of 5:1 ?roger
Well-Known Member
The old cascamite was a casein formaldehyde glue I think and not intended for marine use.
Cascophen was the waterproof glue but dark in colour. Aerolite is good but a bit of a fag to coat one surface with the syrup made from the poder and the other with formalin solution which evaporated rapidly and was probably rather bad for the lungs.
Balcotan is very easy to use, is not gap filling but very convenient for difficult jobs like laminating tillers.
The rapid version foams a lot and will at least fill gaps with foam. In my experience the normal hardly foams at all.
Any of the epoxy laminating resins - with apprpriate thickening additives will be satisfactory but need mixing before use with consequent waste.
Cascophen was the waterproof glue but dark in colour. Aerolite is good but a bit of a fag to coat one surface with the syrup made from the poder and the other with formalin solution which evaporated rapidly and was probably rather bad for the lungs.
Balcotan is very easy to use, is not gap filling but very convenient for difficult jobs like laminating tillers.
The rapid version foams a lot and will at least fill gaps with foam. In my experience the normal hardly foams at all.
Any of the epoxy laminating resins - with apprpriate thickening additives will be satisfactory but need mixing before use with consequent waste.
VicS
Well-Known Member
Re: Cascamite/Extramite failure
Resorcinol is a phenol.
The compound normally called "phenol" is the simplest of a whole class of compounds... the phenols. It is also known as carbolic acid and hydroxybenzene. The latter being the accurate description of its molecular stucture, namely a benzene molecule with an OH group substituted for one of the hydrogen atoms, making it C6H5.OH
Resorcinol is a dihydric phenol so called because it has two OH groups making it OH.C6H4.OH
There are two other isomers namely quinol and catechol which differ by having the second OH group attached in different positions relative to the first.
Catechol, resorcinol and quinol should strictly be called 1,2-dihydroxybenzene, 1,3-dihydroxybenzene, and 1,4-dihdroxybenzene but the attraction of retaining common names is obvious!
You did want to know that didn't you!
Resorcinol is a phenol.
The compound normally called "phenol" is the simplest of a whole class of compounds... the phenols. It is also known as carbolic acid and hydroxybenzene. The latter being the accurate description of its molecular stucture, namely a benzene molecule with an OH group substituted for one of the hydrogen atoms, making it C6H5.OH
Resorcinol is a dihydric phenol so called because it has two OH groups making it OH.C6H4.OH
There are two other isomers namely quinol and catechol which differ by having the second OH group attached in different positions relative to the first.
Catechol, resorcinol and quinol should strictly be called 1,2-dihydroxybenzene, 1,3-dihydroxybenzene, and 1,4-dihdroxybenzene but the attraction of retaining common names is obvious!
You did want to know that didn't you!
pheran
Well-Known Member
[ QUOTE ]
The old cascamite was a casein formaldehyde glue I think and not intended for marine use.
[/ QUOTE ] Sorry, I can't keep up with you chemical types and bow to your superior knowledge. However, I can assure you that Cascamite was indeed intended for marine use - it was just about the best available 50 years ago when I was building wooden boats.
Nurse!.....More blankets please
The old cascamite was a casein formaldehyde glue I think and not intended for marine use.
[/ QUOTE ] Sorry, I can't keep up with you chemical types and bow to your superior knowledge. However, I can assure you that Cascamite was indeed intended for marine use - it was just about the best available 50 years ago when I was building wooden boats.
Nurse!.....More blankets please
VicS
Well-Known Member
[ QUOTE ]
I can assure you that Cascamite was indeed intended for marine use - it was just about the best available 50 years ago when I was building wooden boats
[/ QUOTE ] Resorcinol glues, which were invented by a Dr Yarstey, were used in the contruction of the WWII Mosquito fighter-bomber. 40 different versions were built between Sept 1941 and Feb 1951 when the last of 7781 was delivered. So resorcinol glue was around over 50 years ago but not generally available I guess. The Germans failed to produce a similar plywood 'plane because they did not have a good enough glue!
I don't know why we were still building wooden bombers in 1951 but just imagine a plywood A380!
I can assure you that Cascamite was indeed intended for marine use - it was just about the best available 50 years ago when I was building wooden boats
[/ QUOTE ] Resorcinol glues, which were invented by a Dr Yarstey, were used in the contruction of the WWII Mosquito fighter-bomber. 40 different versions were built between Sept 1941 and Feb 1951 when the last of 7781 was delivered. So resorcinol glue was around over 50 years ago but not generally available I guess. The Germans failed to produce a similar plywood 'plane because they did not have a good enough glue!
I don't know why we were still building wooden bombers in 1951 but just imagine a plywood A380!
CliveG
Well-Known Member
I Have just used Balcontan to laminate a new tiller for our 26 footer.
a 4" x 4" curved blank made with alternating ash and mahogany strips 1/4" thick.
It has done a great job and was easy to cut through and to plane up afterwards.
I would second the comment about the chap at Melco.
He couldn't have been more helpful.
You will need to get all to old glue off 1st.
a 4" x 4" curved blank made with alternating ash and mahogany strips 1/4" thick.
It has done a great job and was easy to cut through and to plane up afterwards.
I would second the comment about the chap at Melco.
He couldn't have been more helpful.
You will need to get all to old glue off 1st.
