White Oak

[Leon m]

I know you guys have probably covered this
topic till your blue in the face.Here goes
anyway!

What is the best glue/epoxy to use on white
oak? Im looking for both strength at the joint
and water protecion.

If your answer is epoxy...does west system
207 hardener and 105 work well for gluing joints etc.

Thanks! Leon

[George Roberts]

I am partial to epoxy with cab-o-sil.

But good joint design goes hand in hand with the choice of glue.

Paint over epoxy protects from water better than varnish over epoxy.

[B. Darrah Thomas]

I use 207/105 faithfully. For White Oak joints, I add some micro-fiber. Time & experience will tell you how much for a given application. Check with Gougeon Bros. for their literature, they have great detail on ratios for their products use.

[Leon m]

What kind of micro fiber do you use?

[Allen Foote]

Well Leon....I'll be the messanger of bad news...so, don't take this personal. White Oak has an acid in it that will cause the failure of glues and epoxies. A year or 2 ago there was this thread on gluing oak and a seasoned boatbuilder chimed in and told how they had glued up white oak back bones for naval mine sweepers. They used resourceinal glue and heated the pieces before assembly and cured at 170 degrees. White oak also does not have the open grain needed for the absorbtion of glues and epoxies. I hope what you are gluing is decrative.

[B. Darrah Thomas]

West 403 mostly. Reasonably consistent results. Look to offer the joint some "glue space". Epoxy works with what is between the joint rather than a glue starved, over-clamped union. I'm not saying show bad joinery, instead back chisel, gouge, drill, etc where you can hide it to allow for some glue. You need to be smarter than the wood you're working with. :cool:

[Concordia..41]

We are laminating white oak frames on Sarah. Some are whole frames and some are partial that are scarified to the old frame. The first whole frames were two pieces of oak that we first steamed and wedged in place to cool and dry before we laminated them with West System epoxy. The last two partial frames we did were three pieces since Margo read in one of the posts that an odd number of laminates are better. They also were steamed and wedged in place before laminating.

After I cut the oak I run it through the surface planer to get the exact size. I then rough up the gluing surface with 36-grit sandpaper. We then steam them in place and allow them to dry to 12% or less moisture. Wash – not just wipe the gluing surface with alcohol. Other people use acetone, MEK or lacquer thinner. We then laminate using West 105/206 epoxy on both gluing surfaces to wet out the joint. We then mix West 105/206 with 406-coloidal silica to thicken the epoxy and wedge or clamp in place. We make sure that we do not force out too much epoxy and end up with a dry glue joint. Unlike Resorcinol that requires a very tight fit, epoxy does not like a tight fit and if you force too much out you will have a dry or starved joint that will fail.

The only oak joints using epoxy that I have know to fail were because of too smooth of a finish on the gluing surfaces and a dry glue joint.

Concordia’s were bad about breaking frames. This they attributed to the steamed frames and the tight planking. In 1956 they did a recall and installed what were refer to as baby frames between the whole frames to correct this problem. The baby frames were laminated using very thin oak. I do not know what they used for glue but it appears to be some sort of epoxy with a filler. We have found a few of the baby frames have de-laminated at the two or three inside laminates but not close to the planking. I am thinking that this is because the fasteners are helping to keep them from de-laminating. None are in bad enough condition to replace so we are just cleaning the joint and injecting thickened epoxy to glue to laminates back in place. They have held up for 46 years so why change them now.

I did contact one person that had a bunch of laminated frames fail. He told me that when he built the frames that he did not rough up the surface and that he clamped the joints too tight. He also said that to save money he used shorter screws than would be normally required as he thought that the laminated frames were stronger. He saved 10 cents a screw when he built the boat. After 10 years he gets to put that savings to work buying new screws and building new frames. Hope he invested that $600.00 in Microsoft!

There are two different views on this subject. Just go through the search on the old posts and decide for yourself what you are comfortable with.

Dave

[George Roberts]

I might mention that the standard shear test performed on epoxy and white oak shows a strength of about 3000psi.

A well designed joint for that brand of epoxy and white oak will limit the shear load to below 3000psi at the shear line.

Different brands of epoxy and different fillers will result in different shear strengths.

[Leon m]

Thanks for the good advice everyone!

Concordia..41 Thanks for the details!

[Frank Wentzel]

Regarding the comment about oak's acid content - If you want to play it very safe: brush a little baking soda (sodium bicarbonate solution ~ 1 ounce per quart of water) on the joint. Rinse and dry before using the epoxy.

/// Frank ///

[ahp]

Would red oak or live oak be better?

[Bruce Hooke]

I've never used Live Oak but there is certainly a long tradition of it being used for boatbuilding. However, others will have to speak up on it's glueability. See a letter in the most recent issue of WoodenBoat for some insight into its hardness. Red Oak glues well but it unfortunately rots quite readily.

[B. Darrah Thomas]

I live in the land of Live Oaks. They are considered a white oak.

[DougC]

There's been a lot of discussion on this one! I had good luck with epoxy and white oak. I roughed up the surfaces and used CPES as a primer. There was a convincing explanation of why this works in one of the many white oak & epoxy threads. Do a search for oak and CPES.

[Andreas Jordahl Rhude]

Allen Foote, I am the one with the experience in gluing white oak with phenol resorcinol adhesive for US Navy minesweepers and for other marine applications. We are in fact, at the present time gluing white oak members for the USS Constitution "Old Ironsides" and a vessel called the Virginia.

We do not heat up the individual laminations (boards) prior to applying the adhesive. The laminations are at room temperature, say 65 degrees F, prior to applying adhesive. The laminations with adhesive spread on them are assembled into the package and clamped into the form. After clamping, the entire gluing form is covered and heat with proper moisture added is introduced into the chamber. The glueline temperature must be at 150 degrees F for six hours according to US Navy specifications. These specifications have been formulated after years of exhaustive research and development by the US Navy, adhesive manufacturers, and the laminating industry.

I am not a ship or boat builder. I work for a manufacturer of structural glued laminated timber. Some of our markets are for marine applications such as minesweepers and new ship construction and renovation of old ships.

[Jeff Evans]

I recently glued my two piece white oak dory transom with 3M 5200 and screwed and glued (with 5200 as well) a white oak cross cleat to its inner face for mechanical strenth. It has some other mechanical fasteners holding the two halves together as well. Thoughts on this glue and application?

[Allen Foote]

Thankyou Andreas for clearing that up. :D Would that be the keel for the schooner "VIRGINA"? I've been reading about it. Sounds like Lane Briggs is all set to race her as soon as she gets built. :D

[bromleigh]

Sorry, have to further muddy the waters...Is Larry Pardey right???Are 2-part epoxies starting to delaminate now that there are enough years in the bank to get a feel for them???He (Pardey) advocates resorcinol for ultimate strength and epoxies only for a cover, if at all.
Roger McNeil

[pcford]

bromleigh wrote: Sorry, have to further muddy the waters...Is Larry Pardey right???Are 2-part epoxies starting to delaminate now that there are enough years in the bank to get a feel for them???He (Pardey) advocates resorcinol for ultimate strength and epoxies only for a cover, if at all.
Roger McNeil I thought that horse was dead! Epoxy is cetainly not appropriate for white oak. "Theories" that it is the lack of surface preparation that causes failure are not correct. There are hard, slick woods that glue successfully with epoxy. Sometimes white oak will glue well with epoxy, but usually not.
I won't go further. This has been covered before. Many times. Use the search function of this bulletin board to review past discussions.

Those that ignore others' experience are in for a rude suprise.