Advice on this toerail joint

[Tatheelrod22]

The pictures tell a better story than words so take a look at the joint I'm trying to make. The wood is teak, and it is 1.5 inches tall, and is 3/4 inches thick. This is my first experience with creating a joint like this. There is a bit more "bend" than the pics show, but one of them shows how wide the gap is in "spring back or natural position"

I have 3M 5200 fast cure, as well as 3M G Flex that I can use, but will obtain something else if it is a better product. When I use a clamp there doesn't seem to have a ton of resistance to it so hopefully it will hold.

So my two questions are as I ALSO welcome any other advice are:
1. Which of these two or what other product is best suited for the joint?
2. Although at only 3/4 " thick I think the size/angle of the joint is fine, but should I have gone at a more shallow angle giving the actual joint more surface area.

Thanks in advance to all of you!

[Kalinka1]

It's a scarf joint that I think is not long enough as it is on the curve of the hull. Teak is awful wood to get glue to adhere to because of the oil in it. What I had to finally do on our boat with teak toe rails was a mechanical clamp through bolted. I used two pieces of stainless steel that were longer then the joint.

[Tatheelrod22]

It's interesting you say that because I'm already thinking in my mind how to do something like what you described with the stainless steel. I also am going to try putting a few half inch stainless screws in there , doing so from the inside surface. They will not be very visible at all and wont go through on the other side. The decks are very narrow on this 25 footer.

[atmartin]

Joint needs to be longer, 8 to 1 minimum, preferably more.

For teak, epoxy is your best bet. Mix an un-thickened batch and wet out the joint with a brush, let it soak in as you mix a micro-spheres (or fibers)/sawdust mixture to be your glue. Use the sawdust to adjust the color. I usually use dust from a lighter wood. It darkens a lot when wet out.

Before you do your glue up, do a dry fit to make sure all your clamps/bolt holes fit and you can get everything in position without a fuss. You don't want to figure out your clamping procedure during a glue up.

Mask off/plastic over surfaces you don't want epoxy on, vinegar or mineral spirits (more toxic, but cleaner) for clean up.

[Tatheelrod22]

I have some of the West Epoxy silicon thickener to create the paste. I've also been keeping the teak dust I sweep up from under my table saw in quart containers. Any reason to not use that?

[atmartin]

Originally Posted by Tatheelrod22

I have some of the West Epoxy silicon thickener to create the paste. I've also been keeping the teak dust I sweep up from under my table saw in quart containers. Any reason to not use that?

406 Colloidal Silica? That's a good choice. Only reason to use a lighter wood than teak is aesthetics, but the 406 will lighten it up anyway. How fine is the dust? Table saw dust might be too big and make your slurry chunky. You could try a test batch. I usually use 60 or 80 grit belt sander dust.

[Lepke]

I do a 3' splice, but I was taught in the olden days. The best stuff I found for gluing teak or any wood is epoxy. I wipe down the joint in teak with epoxy thinner well in advance of joining.
I use a notched splice like below so I don't end up with a thin area and more more glue surface at the ends. Clamping until cured has always been enough no matter the curve of the piece.

[Tatheelrod22]

Yes. The 406 is what I have so I think I'll follow that advice. I'm pretty new at this stuff and ruined a 10" table saw blade ripping something that had a screw in it. I noticed the shavings were much finer with this new blade.I'll save them because I'll wish I had them at some point.

[GordMay]

Originally Posted by atmartin

Joint needs to be longer, 8 to 1 minimum, preferably more.

For teak, epoxy is your best bet. Mix an un-thickened batch and wet out the joint with a brush, let it soak in as you mix a micro-spheres (or fibers)/sawdust mixture to be your glue. Use the sawdust to adjust the color. I usually use dust from a lighter wood. It darkens a lot when wet out.

Before you do your glue up, do a dry fit to make sure all your clamps/bolt holes fit and you can get everything in position without a fuss. You don't want to figure out your clamping procedure during a glue up.

Mask off/plastic over surfaces you don't want epoxy on, vinegar or mineral spirits (more toxic, but cleaner) for clean up.

Indeed.

Scarf joint tapers are generally cut at an angle between 1:8* to 1:10.
*That is, for every inch of thickness in the stock eight inches (or 10") of scarf length is cut. This longer scarf joint will provide more surface area for the epoxy glue up of the rails, making for an even stronger joint.

See also ➥ http://www.cruisersforum.com/forums/...il-184306.html

[davil]

the more likely answer to your project is on a book I highly recommend,"Practical yacht joinery" by Fred P.Bingham.
If you do not have this book will suggest you get it,over the years I have used it not only for my boats projects but also carpentry home projects.
Any ways on pages 242 and 243 he describes with illustrations rails,rails scarfs toerail at bow with techniques including the use of scarfing as well as steam to bend the wood.
David

[keepondancin]

If there isn't a lot of pressure required to bring the joint back together, I would work with what you have. I would use West Epoxy, you can purchase one of their small repair kits that has a few squeeze tubes of resin and hardener, plus some filler, mixing sticks and nitrile gloves.Use the gloves, many people get reaction to epoxy resin. Pretest that the fit is good. Use packing tape on the deck under the joint, and over a larger area of the deck to protect it from epoxy getting on it. Using the packing tape will stop the toerail from being glued to the deck. Make sure you wipe the ends of the scarf joint with Acetone to remove the natural oil that is in teak. That is critical to good adhesion. Properly mix a batch of epoxy, use a little unthickened epoxy to wet the joint surfaces. In the remaining epoxy, add a little colloidal silica, the white stuff in the kit, not the red stuff, micro balloons, as it is very weak. Apply some thickened epoxy on the joint and put it together. When you clamp it, don't over tighten the clamp, you don't want to squeeze all the epoxy out of the joint, but you do want a thin joint. You can use vinegar to clean up the excess epoxy, just don't flood the joint. After 24 hours, remove the clamp, use a razor or utility knife to trim the packing tape next to the toe rail, and remove the packing tape from the deck. You may want to use packing tape on the face of the clamp also, so it doesn't stick to the teak. You may have to do a little sanding to remove epoxy that squeezed out and got on the teak.

[Terra Nova]

Originally Posted by atmartin

Joint needs to be longer, 8 to 1 minimum, preferably more.

For teak, epoxy is your best bet...

This, for sure.

[Greg Mason]

Looking at the picture and your explanation, I would probably have reversed the scarf joint so the spring back was against the joint, not away from it. But if there seems to be little pressure in the spring back, you'll probably be ok with epoxy.

[lolly08]

Whenever I have a project that requires glue, resin, etc I will use 3M -3350 foil tape. It's amazing. Strong, straight lines, and cuts with a razor blade like a hot knife thru butter. Plus, it is super thin.

[GordMay]

Originally Posted by Greg Mason

Looking at the picture and your explanation, I would probably have reversed the scarf joint so the spring back was against the joint, not away from it...

Good catch!