Started the 17' Chinook today!  I began with the stem.  Plans call out a
2x4 on edge, but I thought it would finish much nicer with a 1x4 on the
back edge facing he rower.  Check out the pics and feel free to
comment!

JD

Views: 542

Attachments:

Reply to This

Replies to This Discussion

Thank you very much Ihedrick! That means a bunch! Hopefully I will make some more progress and get some more pics up and running. It has been slow going. Sometimes I just require too much of myself and getting the chines to fit PERFECTLY is really taking some patience. Sometimes I wish I had never seen a drift boat. That way as I follow the plans I would take my time as the outcome would be only known by the plans and the absolute beauty would show itself as the boat was built...BUT...since I have seen everyone's awesome work here, I tend to want to push past the point of letting well enough alone. Oh well, tis wood working!
If moisture is completely kept out to begin with, how would stainless corrode? I am not a chemist, and obviously not good with metals (I'm building a wood boat). I am curious though, as to how something like you're explaining happens? I by no means mean any disrespect to your point, but I am always up for advice, teaching, and correction to better my own techniques! Thank you for your input!
Jordan, I think what Eric is talking about is called crevice corrosion. Stainless, when in an air free/anoxic environment, will basically become un-oxidized (or reduced) thus losing what is its usual defense against corrosion. Though, I always understood this to be more of a saltwater problem. Either way, for this to occur, the screw or the wood where the screw is bedded also needs to be consistently soaked.
So, for a boat like mine which is not in the water for long periods, is garage kept, and used for freshwater (plus all the screws are coated over by multiple coats of fiberglass, paint and epoxy), I wouldn't think it to be much of a problem (probably more than offset by other properties such as the strength of the metal). The use of 316 stainless also helps. I've always been curious about this phenomena as well - if there are any experts, please chime in..
This isn't an easy argument for all boat building (read the wiki info listed by Mr Newman) but the bottom line is that for boats that are usually trailered there is no problem plugging a screw. The decision should be based on the shape of the screw you are using.

I'm going to start with the ending: The combination of a wood screw counter sink and the flat head all purpose stainless screw used without a plug is the worst possible combination of our choices available The wood screw countersink will drill out an area for the throat of the wood screw. The SS all purpose screw has no throat; therefore, the wood area around the all purpose screw threads is not tight and will allow water to track up the threads. This will cause rot in the surrounding wood.

I spent quite a bit of time talking with the boat yards and suppliers in the Seattle area as I was living on ( which means working on) a 40 ft cabin cruiser. While doing this I did my best to sort out the practical use of the screws in the boat yards vs the theory that we see on the web information sites. Here's what I came up with.

1. Water is the boogyman, always.
2. Galvanic corrosion is the cause of screws to fail. The worst galvanic corrosion is below the waterline on salt water boats. Freshwater boats have a much lower risk of galvanic corrosion.
2. Silicon Bronze wood screws with a barrel throat and cut threads are the best if not plugged.
3. Stainless Steel wood screws with a barrel throat and cut threads are second best if not plugged.
4. Stainless Steel all purpose screws (which almost everyone uses because of cost ) have no throat and should be buried with a counter sink and plugged. Without the wide throat fitting tight against the counter sink this screw will allow water to enter the wood by following the threads. Water rotting the wood is going to happen much faster than the screw giving out. This is the most common use of stainless steel fasteners because of the high quality look and the lower cost.

So, here is my conclusion again. The combination of a wood screw counter sink and the flat head all purpose stainless screw used without a plug is the worst possible combination. Unfortunately the knowledge of the surface film not being able to form if a ss screw is plugged lead many to use this combo of wood screw counter sink and the less expensive all purpose SS screw with no throat which will allow the wood to rot out around their fasteners.

Larry and guys, there is lots of info in the/on Wikipedia about this. Probably more than you wanted to know.

Rick Newman
Randy, your reply is exactly what these pages are all about. I don't know of another body of knowledge that allows or covers the subject of constructing framed wooden drift boats so well.

How many years of knowledge are shared by the members here? Perhaps uncountable, and anyway the quantity doesn't matter. What matters is this is a great place to find lots of information and opinions. What works on a trailered boat in Washington may not work well for a boat kept in or near the water in Maine.

If someone wants to know how to build a working boat there is lots of answers and recently we have seen what a fine furniture builder can accomplish, also how to accomplish repairs on beautiful boat that hits a rock.

Both the quality and quantity of information presented lately has been great. My hat is off to all the members that contribute their knowledge.

However if you hadn't started the site we wouldn't have this wonderful repository of knowledge. I know that the administration of the site takes time and money. Thanks for all you have done for Wooden framed Drift Boats.

There, my Thanksgiving chores is done! I am very thankful for all the work everyone has done.

Rick Newman
"Amen" brother!! Thanks Randy, I too, really appreciate everything you are doing for the wooden boat community... awesome!! And Jordon - you are doing an outstanding job on your boat... very well done, man. Can't wait to see the finished product out on the water. GH
It must be the season! November 19, 2008 there was a thread on the Montana-Riverboats forum - plugging countersunk holes. Ray Heater advised against plugging countersunk stainless steel for the reasons discussed here. That was the source of my understanding. Seems the issue is complicated, and if a boat is not immersed continuously in salt water the benefits of plugging might outweigh the risk of corrosion.

If I stand on my roof I can see the Pacific - everything corrodes - aluminum gunnels on canoes, aluminum drift boats, mailboxes on covered porches - so it might be a problem where salt is in the atmosphere.

The points provided by Randy are helpful to all of us amateurs.
Wow, finally got half of the frames done! Sorry there aren't any pictures yet, but priority #1 was getting frames built and notched for the chine. I will keep you posted and get some pics up pronto!

RSS

© 2024   Created by Randy Dersham.   Powered by

Badges  |  Report an Issue  |  Terms of Service