How do these species rate for epoxy adhesion?

[Dooder]

Hello all,
I am planning to build a Gary Dierking Wa'apa and I had a look at the big box store for stringer wood.
Considering I plan to cover everything in epoxy later, which species are good for that?
I've heard that some woods have oil and the epoxy doesn't stick as well as to other species...

Here are my options:

Redwood (Only available in certain thicknesses, might not work for me...)
Maple
Select Pine (no knots)
Poplar (some small knots)
Walnut
Birch
Red Oak

[sp_clark]

Re: How do these species rate for epoxy adhesion?

1.) Redwood – pretty good but structurally not so much, but maybe in CA what you can source locally is better than what I can get where I am;

2.) Maple – hard, heavy, strong enough but doesn't bend well & being so hard doesn't accept epoxy as well as some other hard woods, and rots fast once wet;

3.) Select Pine (no knots) – probably the best of your list;

4.) Poplar (some small knots) – better than maple but also tends to rot quickly once wet, may tend to split when. being bent;

5.) Walnut – great for epoxy, open grain makes for a strong bond; fairly rot-resistant as well but can be heavy;

6.) Birch– heavy, and like maple and poplar can rot pretty quickly once wet. Too, tends to have tight grain that may resist epoxy;

7.) Red Oak – great for open grain penetration, not so much if water gets to it then remains. Fairly heavy as well.

I'd rank them thus for both practicality as well as epoxy bonding: 3, 1, 5, 6, 5, 7, 2

[wizbang 13]

Re: How do these species rate for epoxy adhesion?

You're not just asking about epoxy adhesion, you need to figure out which timber is best for this application. that is more important, they all can be epoxied.
This wap'aha ...its a proa/outrigger.? sixteen feet?
so it may not be the same answer for a balasted monomaran.

[Dooder]

Re: How do these species rate for epoxy adhesion?

Thanks folks for your responses!
sp_clark: that was exactly the kind of info I was looking for.
This will be my first foray in to this kind of thing so I hadn't even considered weight, splitting, rot resistance, etc.

wizbang13: yes, proa/outrigger, 16 feet. 2 pieces.

I have my 1/8" and 1/4" marine ply and now need to buy the timber for the chines, stringers, gunwales, and the bulkhead perimeters...
In the book, Gary mentions Douglas Fir as being good for some of the pieces. I thinking I can use the select pine...

[nrs5000]

Re: How do these species rate for epoxy adhesion?

A quick google search suggests there are a couple of proper lumber yards in your neck of the woods. I’d bet they can supply you with some proper Doug fir. It glued well, is reasonably rot resistant, and has good strength to weight characteristics for the applications you mention.

[sp_clark]

Re: How do these species rate for epoxy adhesion?

...Gary mentions Douglas Fir as being good for some of the pieces. I thinking I can use the select pine...

DF would be a better choice if it's available where you're at. Look for Select Structural dimensional lumber, preferably vertical grained planks with few to no knots and straight in length.

You'll have some sawing to do to 'get out' stock of appropriate dimensions so hopefully you either have your own power tools or know someone who can assist in that endeavor.

Pine is fine for some things but for structural stuff the DF is a better choice for the reasons described in others' posts and it takes epoxy very well. Likely as not it will be less costly than pine, easier on your budget.

[Dooder]

Re: How do these species rate for epoxy adhesion?

My buddy is a cabinet maker and has a full shop so, tools (and knowledge of how to use them) are available.
I will look for douglas fir then.
Thanks for the help!

[Dooder]

Re: How do these species rate for epoxy adhesion?

Ok so I found some really nice douglas fir locally that has no knots and was really straight and clean and dry...
It's $9 per foot for 1x8.
Is that a reasonable price or should I keep looking?

[sp_clark]

Re: How do these species rate for epoxy adhesion?

Ok so I found some really nice douglas fir locally that has no knots and was really straight and clean and dry...
It's $9 per foot for 1x8.
Is that a reasonable price or should I keep looking?

Hmmm... sounds like nice stuff, maybe trim quality if there's truly no knots. That S2S stock, or full 1" x 8" rough-sawn, or planed S4S to 3/4" x 7-1/4' dimension?

@ $9 per foot that's about what I'd expect to pay for trim stock in DF where I am yet that's a little steep if that price is per lineal foot rather than per board foot.

If your budget can stand the hit and your skills are up to making the best of what you decide is 'good enough' perhaps you can end your searching.

I can buy ponderosa pine 1x8's locally for $2/ lineal foot & it's fine for trim or shelving, even building a boat if you don't mind some small, tight knots. Same source has graded 2x DF stock for around $3/ lineal foot; a 2x10 14' long sells for $40, reasonable for construction graded lumber. For a boat I'd expect to have to do some scarfing once I'd gotten out enough material by re-sawing to the dimensions needed.

You raised the question with your cabinetmaker buddy yet? Maybe he can give you some insights as to where you can find proper stock for a better price.

[wizbang 13]

Re: How do these species rate for epoxy adhesion?

9 bux a foot for a 1x8 of fir. ?..bite me hardebr /> bud, get a few 2 x 12's, long ones. re mill them.


or drive to Tacoma and get a load of AYC

[Dusty Yevsky]

Re: How do these species rate for epoxy adhesion?

9 bux a foot for a 1x8 of fir. ?..bite me hardebr />

or drive to Tacoma and get a load of AYC

This. Check the local big box store for construction grade DF. The stacks of 2x's very often have nearly clear vertical grain heartwood. Wider boards can be cut up to yield perfect stock. For some reason I've have very good luck searching the stack of 4x4's at Home Depot. Occasionally I've found perfect clear vertical and tight grained stock.

[sp_clark]

Re: How do these species rate for epoxy adhesion?

9 bux a foot for a 1x8 of fir. ?..bite me hardebr />
or drive to Tacoma and get a load of AYC

S'truth!

(I certainly would if it were a practical choice, but that drive – for me – is a 3,600 mile loop! Maybe the OP's 2,000 mile (out & back) road trip'd be something manageable?)

There's a SS 2x10x16' DF I just signed for at my local yard. Vertical grained & straight, maybe four or five small, tight knots in the whole plank.

5 minute drive w/ trailer over, another 5 to bring home, cost $45 tax included: $1.69/bd.ft., $2.81/ft.

Be enuf + for stringers for the Shenandoah Whitehall I'm planning for.