Teak bow pulpit assembly pins

[Rikster]

Hi all
I have an 86 Chris Craft scorpion, I removed the bow pulpit to refinish it and found that all but two of the twelve dowel pins holding it together have rotted away. Reassembly shouldn't be a problem but I am wondering about the pins and glue. The pulpit is now in four pieces which I need to re-pin and re-glue. Obviously I need to use marine grade wood glue, any suggestions on that?
As far as the dowel pins should they be made of teak as well or should I just stick with regular hardwood. I found a supplier of teak dowel rods of which I could fashion my own pins but the originals must have lasted a long while. The pulpit looked really beat but was in surprisingly good structural condition except for the rotted pins. Anyone have any experience with this?
Thanks
Rick

 

[Bob_VT]

Re: Teak bow pulpit assembly pins

You can use hardwood or teak. As far as glue....... you can use epoxy and it will never come apart or even consider gorilla glue which is a waterproof glue.

I would go with epoxy and extra support braces.

 

[Rikster]

Re: Teak bow pulpit assembly pins

Thanks Bob

I'm just going to use hardwood pins and expoxy the pieces back together. Hopefully that should keep the moisture at bay for a while
Rick

 

[Paul Moir]

Re: Teak bow pulpit assembly pins

You might want to consider first precoating the dowels with epoxy or thinned epoxy if at all possible to help preserve them. Remember too epoxy works better with a loose fit, as opposed to regular wood glues.

 

[Rikster]

Re: Teak bow pulpit assembly pins

So your saying I should sand or undersize the pins somehow if I use epxoy? What about expoxying the boards together, I envisioned applying epxoy and clamping them tightly together. Is that not recomended ?
BTW the teak has turned out beautiful after a good scrubbing and sanding. I am thinking of using a sealer afterwards to lessen the maintenance a bit, any pros or cons anyone has had would help.

Also I want to seal out any water laying between the teak and the fiberglass base and prevent it from leaking into the boat, would this be an appropiate use of a bedding compound or should I just use a marine type sealant? Someone had tried sealing around the wood with silicone but needless to say it didn't work very well.

 

[Paul Moir]

Re: Teak bow pulpit assembly pins

Bright teak is a blessing and a curse. It looks beautiful but maintaining it is a pain. Oiling with teak oil is the "correct" way, but it needs to be renewed every couple weeks if the boat is left out in the sun.

Second is spar varnish. This contains UV inhibitors which keep the teak bright. The downsides are that the varnish gets used up over time, and that getting anything to adhere to oily teak is tricky. Even if you wash the teak with acetone first and thin out your first layer of varnish, you can plan on yearly maintenance with varnish. And applying varnish is a fair amount of work with many coats, long drying times and required sanding between coats. But the finish is second to none.

Third is a specialty product like Cetol. This stuff does colour the teak and dulls the grain, but it lasts a long time (many years) and maintenance is easy.

I'm leaving out a few options, including epoxy encapsulation followed by spar varnish, since I haven't tried them out yet. That might be worth looking into though, I've heard it looks as good as varnish alone but lasts longer. Since the varnish does break down over time you would still want to sand (not strip though) and recoat your teak. How often you do depends greatly on the quality of the spar varnish as UV inhibitor performance usually goes up with price.

As for the epoxy, yes, it is not the ideal glue for good fits. You really want to be a little sloppy with your fits when working with it. For example you would want about a sliding fit on your pins. Avoid clamping tightly - just enough to get the parts to contact is enough. If you need tight fits, slightly thin your epoxy (with a very small quantity of acetone < 5%, as it reduces strength) or use a naturally thin epoxy like Epiglass.

I would do all you could to avoid having to go to resorcinol or some other adhesive that is more compatible with tight fits. If you do go to another though, I've had good luck with plastic resins. I don't think you can get the stuff I use there (Dural Marine), but it's akin to WeldWood Plastic Resin Glue.

You're definitely going to want to use a sealant for where it joins to the hull. Avoid polyurethanes like 4200/5200 since they are really adhesive sealants that don't lend themselves to later removal. Polysulfide caulk is what you want to use here. It's to be found in any chandlery.

 

[Rikster]

Re: Teak bow pulpit assembly pins

Paul
Thanks first of all for you interest and help in my project, it is greatly appreciated.
I pinned and dry assembled the pulpit to have a look at things and either due to warpage or its original manufacture the wood does not have a real tight fit. Maybe that is why water seeped in and rotted the original pins. That rules out any standard wood glue that would require a tight fitting joint. I am looking into two options one is west marines 105 resin plus hardener and adding their 403 microfibers for a strong bond.
The other is a product I found online which is called oak & teak epoxy glue http://www.glueoakandteak.com/ they claim their product is flexible. Anyone ever heard of it or used it?
One of the major detractions I found online against using epoxy on teak is it is assumed that the teak will be sealed and not subject to expansion and contraction. Being that epoxy is so rigid and oiled teak breathes the dissimilarities would cause the joint to prematurely fail. One thing I have found is that from boat restores to woodworkers everyone has their own method of assembling teak and they are all contradictory to one another.

I haven’t really looked into the finish aspect yet as I am more concerned with getting it back together but the epoxy encapsulation would solve the afore mentioned problem, the oak and teak glue company make a product like that as well.
Thanks for the advise on the deck seal I might have goofed on that one and used 5200.
Thanks again
Rick

 

[Paul Moir]

Re: Teak bow pulpit assembly pins

Fillers make all the difference in the world with epoxy. Normally, I use wood fiber as a thickener when bonding wood parts since a high strength bond is not required (no need to be any stiffer than the wood) and a little flex is good. I imagine it works much like the 403 microfibers which I understand is cotton based. Fortunately, teak's expansion/contraction is inherently minimal compared with other woods. Even unencapsulated, it's very stable.

Note that with any of these "strength" fillers, sandability is a real problem. Try to clean up as much as possible while still flexy but not sticky. At that stage, you can readily remove any squished out stuff with a sharp chisel. If you mush it around while it's still wet, the parts wetted out by the epoxy/filler combo will finish differently than the unwetted area unless you do real extensive sanding.

I think I may have encapsulated teak already with some success. I'm just not certain about the particular variety of wood I was using, and if it truly was teak or a look-alike. Either way it was a very oily wood. It took to epoxy and encapsulation just fine after it was well washed with acetone to remove the oil near the surface.

Stick with what you hear from boatbuilders about teak. Many so called "waterproof" adhesives fail miserably on boats. There's a world of difference between a lovingly cared for piece of furniture and an abused, ignored fitting left out in the sun or submerged in salt water half the time.