strip-planked hulls

[Puzzled]

a boat im considering becoming involved with has a strip-planked hull .my previous boats were carvel planked which im familiar with . this vessel is 47ft and most of the construction method i understand, however what i dont is the entire lenght of the bottom from the chines to the keel there is a grid of screws facing outward installed at the build time; can anyone shed some light on this for me as to the purpose, and how it effects future repairs if needed.

[Oyster]

I am not sure if I understand you. But normally in strip plank construction fasteners are placed from one strip to the other in this manner. Fasteners are also run into the framing, too.

[Puzzled]

thank you for the reply Oyster, what i do understand is up to point that you showed in the photos, however after that level of the bottom construction another phase was introduced to the build. this is what im curious about. the grid i spoke of is set up in about 5" squares with the fasteners facing from inside the bottom outward as if it was holding another layer of bottom material in place ,the boat was built by bob sherbert in 1962 so its obvious its one of his methods and i would like to understand it before i proceed with a possible purchase. hull looks extremely sound, but i havent pulled the boat out to look a underside yet till im a little more familiar with the construction

[Oyster]

Is the the boat?



http://www.fishunclebuddy.com/

I think that what you are viewing is called butt blocks. I would be interested in knowing if the bottom planks are really strips that are about 1" or 1 1/2" pieces or wider. It would make more sense that the boat has wider planks with five inch blocks exposed. Do you know if the hull has an outer layer of wood, skinning it and glass over?


"Butt Block - A short longitudinal piece of wood used to back up the connection of two plank ends"

Check out this thread. There is a guy that worked with him in Daytona. I do not know if he still posts now. But send him a mail.
http://boatdesign.net/forums/showthr...?t=9612&page=5


Another thing that you could be viewing is blocks that back up plugs that filled what used to be thru hulls if the hull has some age on it.

[catmando2]

any strip plank hulls i've had anything to do with have no fasteners at all.

temorary screws to hold to temporary chip board frames yes, but once glue has dried,sand and glass inside and outside using epoxy resin

[Puzzled]

we're making some progress oyster, i sent an e-mail to wdnboatbuilder i believe thats who you were talking about in your last post. its not the butt-blocks that you mentioned these fastenings are on the bottom layer thats fastened to the frames and theres atleast 4000 of them because they cover the entire bottom from the inboard side facing outboard

[Puzzled]

yes oyster thats the boat but its not the uncle-buddy its a sister

[Oyster]

Are you able to take any digital pictures and post them? Oh quick question, lightbulb moment, does the interior bottom planks have fiberglass on it?

[DGreenwood]

I have seen some boats (some by Derecktor) where marine ply was bedded onto the interior of the planking between the frames and many screws driven from inside. Is this possibly what you are seeing? These were on glued seam construction---not strip plank, but carvel without caulk seams.
On the two boats that I am familiar with it was an effective method. Some of it had to be replaced but it turned out to be no big problem. We relaminated with epoxy and thinner layers of marine ply.
I will see if I can find the pictures but I fear I lost them in a harddrive crash.

[Oyster]

Batten seamed construction on planked hulls are normally notched into the frames and run continuously and not normally pieces between the frames fastened between the frames. Normally fasteners are from the outside. I can't imagaine that someone added pieces after the fact screwing them from the inside. A common practice with some builders of strip plank hulls is adding plywood between the frames and glassing in place. Also some people staple fiberglass with the mindset that it keeps it from delaminating but this is done normally upward or on vertical surfaces and really serve no use after the resin dries under most cases. Hum..

[DGreenwood]

Oyster
I was surprised by it myself. But since I first saw Figaro (Bill Snaiths Famous Transat Winner) I have actually seen others. It seemed really durable and was not an after thought. It was installed from new.
Bob Derecktor did quite a few like that.

[Oyster]

Well I am not sure of the benefits versus some of the downsides of batten seam only between frames, IMHO. I take it that they run the length of the seam from one frame to the other? If so the mindset for me stems from the many crevices that are created on each ends and basically waterstops for both "crud" and dampness to gather. If the boat has a glass bottom, this maybe minimized. Butt blocks rarely extend much more than two to three inches or so from the butts, which is on wider planks and not normally on stripplanks that are only 1" to 2" wide. We alway cut mitres or long angles on the ends and continue on the strips with another one. BUt from the maintainance end of it, I would consider this to be a downside for me. oh well..........

[DGreenwood]

I guess I have not described it very well. The panels covered the entire space between the frames. They were not battens.
To get back to the original question I think we need some pics to have any idea what we are talking about here.

[Oyster]

Most of my thoughts are just from what I have experienced. I have no experience with this particular hull. But over time, different eras of boat building, even with different builders goes through some phases that are common across the board. At this time I am going to bow out until I can see the application. Most of what I have conveyed is all hypothetical and thread filling. I did not find any real detailed information on the building specifics for the actual boat. Later

[Puzzled]

okay gentlemen i thank you for your replies , on saturday the 18th i'm taking the boat for a little sea trial so i'll take some pictures of the hull bottom and look for some of the other things that have been brought up like the plywood between the frames or glass over the bottom on the inside , the hull is painted on the inside from the factory and considering the age of the boat its in extremely good condition . get back to you on saturday evening . till then keep the slimy-side down