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View Full Version : Black Locust sampson post finish?



Greg Stoll
11-15-2010, 06:07 PM
Hi all,

I'm very near the end of my Brockway Build:

http://forum.woodenboat.com/showthread.php?119481-Building-a-Brockway

I'm planning on using some Black Locust supplied by David G to build three sampson posts with 1/4" stainless steel crossbars. A couple questions:

1. What kind of finish should I put on the posts? Do I even need a finish? Is this wood hard enough and with enough rot resistance that I can just leave it be?

2. How do I secure the stainless crossbars? I bought some 6" x 1/4" stainless bolts, the threads are only on the distal 1" which leaves me slightly less than 5" of crossbar. I plan on drilling the hole and tapping the bolts in, then cutting off the thread and head. Does that sound reasonable? Will it stay in with just a friction fit?

Thanks for your help,

Greg

Tom Lathrop
11-15-2010, 07:39 PM
You can drill a small hole in the side through the 1/4" pin and tap in a small pin. I did this once with the pin from a stainless pop rivet. The hole in the rod can be drilled first and the small pin sharpened so it can find the hole when driven in. Worked ok. Another time, I cut some grooves in the center of the pin and set the thing in epoxy. That worked ok too. Maybe you could get away with just forcing the 1/4" pin in and hoping for the best but that seemed iffy to me. Maybe there is some time honored way to do it.

gibetheridge
11-15-2010, 09:23 PM
The post must have end grain on the top, I would get as much thinned epoxy as possible to soak into the top, then seal the whole unit with epoxy, then varnish or paint to protect the epoxy from UV.

For the pins I would drill a 3/16 hole all the way through then twist in a bolt from each side until they meet in the middle, then cut off the heads. I would consider coating the inside of the hole with epoxy as well, maybe with a Qtip, or maybe just fill it up and let it soak in for a while, then screw in the bolts while it is still wet, the idea being to eliminate voids and to seal the end grain in the hole.

Spokaloo
11-15-2010, 09:34 PM
Greg, seems like the perfect piece to do an old school boat soup coating of linseed and turps. Or (this is my furniture buddy's favorite) just go to town with shellac and keep recoating until you get that nice thick layer on the outside. Both are easy to maintain and tough.

E

Peacefuljourney
11-16-2010, 09:09 AM
Black locust is one of the wood resisting the most to rot, so forget the epoxy over it it's pretty much useless.
You can buried black locust in dirt, and get it out exactly the same years later.

The post will stick out at the sun with nothing to help to don'T dry too much. So you got to protect it from the sun the most, you got for choice oiling it, or varnishing it.

Oiling ask for more repetive work, but I prefer this one as lines will chafe varnish or anything coating you gonna put on that. Soaking the pieces a few days in oil (Find yourself a nice recipes of oil there is plenty, I am a raw linseed (70%) & kerosene fan (35% I know it doesn't give 100% but I mix by eyes most of the time!))

JimConlin
11-16-2010, 10:30 AM
I'd consider tacking a bit of copper over the endgrain. Bed it well.

If the holes for the pins are bored a bit undersize, the pins won't move around. The load on them is not axial.

I'd cut the threads off and round the ends before driving the pins. They'll drive more easily. A bit of soap in the hole won't hurt.

Draketail
11-16-2010, 11:09 AM
Here's the samson post treatment on the Pld Point at the Chesapeake Bay Maritime Museum. I imagine the lead is bedded in Dolfinite or something similar.

http://inlinethumb35.webshots.com/37410/2803279270102980561S500x500Q85.jpg (http://community.webshots.com/photo/2803279270102980561QMsOuc)

Greg Stoll
11-16-2010, 11:18 AM
Thanks for the replies guys. I think what I'll do is notch the crossbar in the center, the drill a hole in the wood from the top down to one side of the crossbar hole. I can then thread in a stainless machine screw to lock everything in place. Then maybe a small Black Locust cap over the top?

Greg

Greg Stoll
11-26-2010, 11:48 AM
Don't know how or why this thread got closed, but here are the sampson posts I ended up with.

I started with the black locust sticks, roughly 2 1/4" x 1 1/4". I planed them smoothish and drilled a 1/4" hole across each one, then drove a 1/4" x 6" stainless steel bolt through. It stayed in remarkable well:

http://i245.photobucket.com/albums/gg58/Gregstoll80/Brockway%20Build/CIMG0355-30.jpg

I then cut the head and threads off:

http://i245.photobucket.com/albums/gg58/Gregstoll80/Brockway%20Build/CIMG0356-30.jpg

The cutting marks were filed off and the edged rounded. And here we have a sampson post:

http://i245.photobucket.com/albums/gg58/Gregstoll80/Brockway%20Build/CIMG0357-30.jpg

I've installed them on the boat with 1/4" stainless bolts and large fender washers. Launching is tomorrow, hopefully they'll hold up!

Greg