Oak ribs..Steam vs Laminating?

[Ralphw]

well, I have come this far and was going to put off replacing about 10 ribs on my 17.5' 1961 Grady white until winter so I could finish the boat and get some "in the water time" this year, then thought better of it and I feel I can do this quick..sooooo...

I doubt very much I can find green oak in a timely manner to steam so I plan on laminating them. I have done both laminating curves and steam bending but never for a boat. it was for curved railings and moldings etc.

any pros or cons on doing it this way. I know it will not be exactly as original but no one will ever notice.

I plan on removing a few ribs at a time(maybe every other one) and making a glue up jig, slicing some white oak into 1 1/8 x 1/8 strips..6 strips each and either useing gorrila glue or epoxy.

I dont see any reason why laminated would be inferior... am I wrong?

can I steam oak right from the lumber yard?

See picture here (http://ralphw.net/ribs.jpg)

[ 08-29-2005, 09:29 PM: Message edited by: Ralphw ]

[ssor]

With six strips you have five long glue joints, if anyone of them is defective then you frame is that much thinner, from a structrual point of view. I should think that Donn knows of a sawmill on the island that could supply you with green white oak. You only need a couple of planks.

[Ralphw]

that would be great....I would definatly prefer to go that route if I can find it

[Domesticated_Mr. Know It All]

Try this website.

http://www.woodfinder.com/

good luck. ;)

http://ralphw.net/ribs.jpg

[ 08-29-2005, 10:14 PM: Message edited by: Mr. Know It All ]

[Ralphw]

while I'm here on this topic ... the ply directly under and limited to this area(one plank right at the tight bend of the rib) has shed 1 layer of ply... the wood under it is very sound. I am carefully removing this flaky layer and laminating a fresh skin of mohagony cut to fit and using epoxy to glue it down then refasten it with the machine screws and nuts.
sound right?

when I got the boat it sat on the trailer kind of cocked to one side ... I asume rain got on the flor and ran in this direction... of the edge of the floor and on this one plank which spread to the ribs on this side other side seems ok for now, not great but ok.

If this goes how I hope it does I may do the other side before last coats of paint go on

[Ralphw]

Mr. Know It All
thank you for that link. it seems that my regular supplier has green wood will call tomorrow and see TY

[ 08-29-2005, 10:25 PM: Message edited by: Ralphw ]

[Ralphw]

assuming I'm able to get the green oak....can I steam and just force the rib against the hull and screw it?

[pcford]

'Round Seattle at least, bending white oak is usually not available in the summer.

[George Ray]

Google:
(1) steam bending oak
(2) steam bending oak boat
The results seemed rather rich with info.

I have had good luck just soaking thin oak and surprizingly, maple(not for bilge frames).

I think steam=>bend=>clamp=>fasten as quick as it can happen would be fine. I have been around steam bending but have mostly an arm chair association with it.

[Bruce Hooke]

Originally posted by pcford:
'Round Seattle at least, bending white oak is usually not available in the summer.This is a point worth considering...if the oak you buy has been drying for more than 6-8 weeks then it will no longer be "green" and it will likely be getting close to "air-dried." Wood, even white oak, dries more quickly in the summer than it does in cooler months. I would not consider this an issue if it were not for the fact that you are trying to achieve some relatively tight bends (based on the picture*). Still, if I were you I would be inclined to go ahead and get a board or two and give it a try. I was able to achieve bends about as tight as yours with some white oak I bought in late October (an even worse time than now). I milled out the pieces I needed and soaked them in water until I was ready to bend them. To soak the wood I made a "tank" out of PVC pipe with an end-cap glued on one end and another free end cap on the other end with a hole in it to use as a handle. The second end cap was necessary to force the wood down into the water.

*If the frames you are replacing are not tightly curved like the ones in the foreground of the picture, but are instead up near the bow, then you could almost certainly get away with kiln-dried lumber straight from the lumber yard. Some of those ones near the bow look almost straight, however, those are rarely the frame that break!

[holzbt]

Harned Brothers Sawmill- Commack

Suburban Mills- Huntington Station

They are both in the phone book. Good white oak is a crapshoot around here. Sometimes they have it and sometimes they don't.

[Chadd Hamilton]

Ralph, for what it's worth. I've just finished a complete re-ribbing job on my 1953 Lyman 15 (similar to the boat mr know it all posted above). There were some some pretty tight bends especially near the stern. I used kiln dried white oak that I purchased from a local Woodcraft store and only broke one rib in the entire process(about 20 in all).

Bottom line, if you can find green oak, then use it. If you can't, as was my situation, then use what's available. Just make sure it's up to bending temperature and go to it.

Chadd

[Mrleft8]

"Green" isn't as important as "Air dried". The White Oak I used for the frames (ribs) on My Cats paw dinghy was air dried for at least 10 years. It's MC was about 11%. The deal is.... Air dried lumber will absorb moisture better than Kiln dried lumber. Kiln drying has a tendency to collapse the cell structure of the wood.

[Ralphw]

Thanks everyone. I will try those places now... wood-ply has white oak but could not tell me if it was air or kiln dried.

PS the boat in the pic is mine and yes the ribs in the forground are the ones that need to come out more so on the other side.

[ 08-30-2005, 01:58 PM: Message edited by: Ralphw ]

[holzbt]

The chances of Woodply having air dried oak are slim. I'd put my money on it being kiln dried. You'd be better off buying air dried from Condon in White plains if you want to pay lumberyard prices. The mills will be less $ if they have what you need.

[Jim Budde]

And use Ken's "steam-in-a-bag" procedure .. gives you lots of extra work time for hard to get at bends. Once wood is secured in place, puncture the bag, let the steam escape and you be done

[Bruce Hooke]

Originally posted by Ralphw:
Thanks everyone. I will try those places now... wood-ply has white oak but could not tell me if it was air or kiln dried.As a general rule, I'd say that any place that does not know is selling kiln-dried wood. In my experience you usually have to go straight to a sawmill to get air-dried stock, or a VERY FEW special places that specialize in supplying wood to boatbuilders. According to one knowledgable lumber dealer I talked to, it just does not pay for the average hardwoods dealer to mess around with air-dried stock.

[Ralphw]

got it! smile.gif found it at suburban mill in Huntington setting right next to the saw

I removed one rib to see what kind of a job it would be and I didn't think of this but the ribs are screwed to the stringers and keel before the planking goes on :confused:

[David W Pratt]

My experience with oak is that epoxy does not glue it very well. Maybe the acid inthe wood.
Good luck.

[Ralphw]

going out now to rip the ribs and maybe steam a rib or 2 tonight, I guess I will just screw through the hull and rib into the stringer and keel where it was originally done before the planking went on

[ 08-31-2005, 11:40 PM: Message edited by: Ralphw ]

[Domesticated_Mr. Know It All]

That appears to be a clinker-built style boat.
The screws could be bronze. The ribs are first clamped while hot,then drilled and rescrewed from the outside of the planking. Then the screw heads are filled or bunged. You can use all the goop necessary to help but remember the fasteners are what really hold the boat together.

Ain't this fun? :D

http://www.imagestation.com/picture/sraid138/pd74029479a133494292ba987a902f285/f713fe29.jpg

[ 08-31-2005, 09:43 PM: Message edited by: Mr. Know It All ]

[Ralphw]

Yes its a lapstake boat ,,, very similar to the one in your pic

yes all bronze fasteners keeping it that way with any new ones

I had some success tonight...
built steam box with teakettle and hotplate

cut a piece of oak and chamfered the edges just llike the originals
and managed to steam it and what do you know..... it went in right where the old one was and looks great. I would love to do em all but...hmmmm where does it end?

BTW I forgot the gloves... i wont do that again

[ 08-31-2005, 11:39 PM: Message edited by: Ralphw ]

[Ralphw]

well 2 went in smooth as silk from one board...have 3 of those left..

3 from the big board I had all split right away have about 16 of those left :(

the grain looks nice and straight..oh well

back to the saw mill if I can get out of work early enough

i'm going to bed

[ 09-01-2005, 09:54 PM: Message edited by: Ralphw ]

[JimD]

I don't know if the oak board used here was air dried or kiln dried but it's at least a few years old and kept in a very dry climate. This morning I cut a strip with the table saw from the board I have kept handy, did not steam bend or even pre-soak. Just wrapped it in an old bath towel, poured a kettle of boiling water over it, and bent it around the plywood jig for a kayak combing. I will epoxy laminate another strip to it later. It's amazing how oak will bend like almost no other wood

http://www.imagestation.com/picture/sraid184/p915de2dd14bfc69f70266e72b1d0b2ec/f27afa5a.jpg

[Ralphw]

ok.....

got about thirty done....all of the bad ones are gone.

they just broke apart in my hands as I took em out

http://ralphw.net/ribs2.jpg

the rest seem pretty good, but I would like to put some "helpers" at the bottom of the ones that are left. I put some pieces in there so you can see what I mean....is this done? will this be ok?

the ribs or pretty solid but the bottoms are slightly punky and this seems to be a way the lessen the stress on them... or should I just continue with the bent ribs?
http://ralphw.net/ribs3.jpg
thanks for everyones help on this project.
I really appreciate it.

[pcford]

Looks good! Congrats on a nice job.

[pipefitter]

Yeah,no doubt.Looks great.