Glueing Silky Oak

[retep52]

I am about to glue up a Silky oak blanket box top; can anyone help me with which specific glue to use; I also need to know if Silky oak will take a standard Mirotone lacquer ??

retep52

[MajorPanic]

Any usual woodwork glue will do & Silky polishes very well! I've used HEAPS of it with Mirotone 3210/30 lacquer & it's fine. ;) :D

[retep52]

Thanks for the advice MP but I have made several trial joints with PVA (12 hour press time) and all failed on the glue line. However, I also made one with epoxy which I tested this morning and the timber broke away from the glue line, so I may go with the epoxy.

[PAH1]

retep

have you checked the state of your glue- it does go off with time and it may be that rather than the timber. I have glued both Cardwellia and Grevillea silky with PVA and cross linking PVA without issue.

[Don Nethercott]

Don't use your standard PVA glues. You need the waterproof PVA's such as the Triton or Selley's Tradesmans Choice.

Haven't heard of the lacquer you are using, but does it contain Tung Oil. Definately the best ingredient to have in any finish.

Don

[Andy Mac]

The Silky oak rocking dragon I just made was glued together with Araldite (epoxy) and no problems, but I've also used cross linking PVA which works fine. As PAH says, check the use-by date. This stuff doesn't last longer than a year esp. in a shed with temperature extremes...like mine:o !
Watch out for excess glue, as it is hard to remove from open grained timber such as Silky. Wipe up with a damp rag when uncured.

Cheers,

[retep52]

Thanks Pah, but the glue is fine; I think I may stick with the epoxy

[retep52]

Thanks for your input Don

[retep52]

Thanks Andy, I have been making solid timber furnature professionally since 1971, but this is the first time I have ever used Silky Oak; I will post a pic when "she" is finished.

[journeyman Mick]

Retep,
I've glued together quite a lot of silky oak, both Cardwellia Sublimis and Grevillea Robusta and have never had any problems using PVA, X linking PVA, Polyurethane or Epoxy. Use the epoxy by all means, but you may want to test your batch of PVA on some scrap timber of varoius species as it may be off.

Mick

[powderpost]

I agree with Mick. Polishing with lacquer is also no problem, however silky oak (both species) is a very open grain timber and does need quite a bit of grain filler.

Jim

[retep52]

Thanks Mick, I will buy new glue today and test both old and new; hopefully it is the glue batch that is the problem and not the timber.

[retep52]

I have been trying to download pictures of my tests for glueing Silky Oak but so far it seems I do not have permission to do so. What must I do to allow this to happen? The pictures show in great detail the problem I am having with adhesion and I thought perhaps there may be one or 2 out there who would be interested.

[brit_in_oz]

Depending on the type of PVA over time they age and the molecules increase in size. the key to PVA forming agood bond is having enough small molecules that can penetrate into a wood. An old glue, especially if been left at high temperatures will have a far larger molecular size, hence the chance of getting a good bond drops. this is also seen by a viscosity rise, an old PVA will be thicker than a new PVA.

the other thing is that the thickening additive in them is very susectible to fungal / microbe attack, and they can feed on the product which doesnt do the chance of glueing any good.

PVA also has a 'chalk point', this is a temperature under which the PVA willnot form a continous film, andtherefore will not bond. Usually this is between zero and 10 degrees' but if it was warmer than this it should not be a problem.

The only other thing coud be if you have used a stain or oil that is interfering with theglue ine.

[Mike Jefferys.]

Not all PVA's, even if apparently the same generically, are the same. Like so much else in recent times common or garden white PVA's are often re-packs from imported sources where quality maybe suspect and where quality control is also an issue. There are now a range of PVA's from single pack white right through to two pack cross-linking. In the middle are so called yellow glues which have a harder cure, lower creep, machine better and which offer a much stronger glue up. It also glues slightly greasy timbers like silky especially well (it was actually formulated in part to glue MDF which has a waxy feel). We market AV180 as our House brand. It's made by AV Syntec in QLD. We date every bottle with a use by (which BTW is a very conservative time) and a batch code. It can be mailed in the regular post. Final points. You usually get what you pay for. Expect to pay high teens to low twenties for a 1/2 litre.
Apologies if the ad offends
Mike Jefferys
http://www.thewoodworks.com.au/details.html?eqskudata=C0003

[brit_in_oz]

I wish people would stop perpetuating the myth that Yellow glues are somehow better , its a marketing gimmick that has been aroud 40 years. PVA's are defined by the D rating, D1-4 which is a measure (in general terns) of the resisitance to degradation of water. Yellow glues, are in general, D3 PVA's, which are also known as water resistant or cross linking PVA's and they have a yellow dye added. Two part PVA's are D4 which is the top rating and generally require an external hardener / catalyst to cross link them above D3. (That being said my company has the first stable one part D4 on the world market, but i am not here to market anything).We sell white and yellow D3's and their is zero differece between them except the colour.

The strength of ANY PVA will be similar, because PVA works by penetration of the polymer into the woodfibre, even a D2 will give you fibre tear and not adhesive failure. The difference is the water resistance (due to cross linking, and also solid content. D3 and higher have solids around ~50% whereas a lot of D2 have solids around 30% (or even lower), which means you get less effective glue for per ml


QUOTE=Mike Jefferys.]Not all PVA's, even if apparently the same generically, are the same. Like so much else in recent times common or garden white PVA's are often re-packs from imported sources where quality maybe suspect and where quality control is also an issue. There are now a range of PVA's from single pack white right through to two pack cross-linking. In the middle are so called yellow glues which have a harder cure, lower creep, machine better and which offer a much stronger glue up. It also glues slightly greasy timbers like silky especially well (it was actually formulated in part to glue MDF which has a waxy feel). We market AV180 as our House brand. It's made by AV Syntec in QLD. We date every bottle with a use by (which BTW is a very conservative time) and a batch code. It can be mailed in the regular post. Final points. You usually get what you pay for. Expect to pay high teens to low twenties for a 1/2 litre.
Apologies if the ad offends
Mike Jefferys
http://www.thewoodworks.com.au/details.html?eqskudata=C0003[/QUOTE]