Steam bent frame repair

[Tangusso]

I recently purchased a 1935 Richardson Cruisabout, 32'. She is in very good condition structurally, mechanically, and even cosmetically, with a few exceptions. Per the usual standard of the day, she was framed in white oak and planked with what appears to be mahogany. Fastenings are silicon bronze in excellent condition. Despite the fact that the ribs and floor timbers appear to be rock hard and rot free right down to the keel pockets, there are several fractured ribs.

In reading Jim Trefethen's "Wooden Boat Renovation", I see there is an acceptable practice of repairing sawn frames by graving in a piece of wood, ensuring proper grain orientation, and using thickened epoxy to join the rib pieces into one member. My question is this......Is there a reason I cannot do the same thing with steam bent ribs? I propose to bend a 24" - 36" section of new rib right next to the old and temporarily fasten it in place to allow it to set (with a bit of shim at each end to compensate for spring back). Once the new piece is cooled, I intend to cut out the damaged rib section and shiplap the remaining ends. I will then shiplap the new rib ends to mate with the existing, epoxy the rib sections together, and screw planking back to the repair as it originally was.

Can an experienced member please comment? I need to know if this will be a safe repair.

[J.Madison]

I believe new frame heads/heels are commonly scarfed into place when only part of a frame is rotten. If I am understanding what you are saying the sketchiest part sounds like the shiplap. Use a proper scarf joint. It might be better to just replace the entire frame. Smarter people will help you soon.

[Tangusso]

Unfortunately I am unable to replace entire ribs in most cases, given that the boat is completely assembled and in sound condition. The covering boards are in great condition and are covered in canvas. I can remove tanks and other equipment to gain decent access, but most of the breaks are at the turn of the bilge, and if there is a proper method to repair this section I would prefer to do that.

I have been told that epoxy and white oak may have some potential issues. Can anyone comment on this??

[J.L.L.]

Leaving the broken frames as they are and adding long sister frames between the existing frames may be an option. It would eliminate glue joints and potential weak spots in your frames.

[floatingkiwi]

Sistering frames adds weight, leaves bad stuff behind that WILL transpose its weak point to the sister and break it in the same spot. And a few other things. Steaming frames will always weaken them and they will break one day. All of them.
If I was building new, I would laminate frames all the way.
I do't see why you would want to add a steamed frame section alongside the break/repair temporarily. WHy would you want to do this? Are you worried about spring in the existing frame. Trust me, there is none, or very little anyway, and nothing that wouldn't be taken care of by neighbouring members.
Don't be too elaborate.
Just take a disc grinder, yeah a handheld grinder, and grind out the break and a smooth curve up and away from the break area in each direction along the frames line..
Imagine a big flat dish shape with the place where it was cracked, at its bottom.
Then laminate pieces into it so there is material filling the space where the frame will exist,( and did),and when it is dry, plane, grind, spokeshave, gnaw off all the excess, sand it smooth with a block of wood with paper wrapped around it, and she is good to go mate.
If you warm the strips first and soak unthickened epoxy into the surfaces before thickened, tenacious, gap filling wonderful stuff epoxy is, I reckon it'll hold. It did for me. Others may disagree with the oak epoxy thing. If you are unsure there is a product by West called G-flex and it is epoxy formulated for difficult to glue wood, like oak, for example.
I found some pics I took straight out of a book by people all around us.

http://dl.dropbox.com/u/35691595/P3100001.JPG

http://dl.dropbox.com/u/35691595/P3100002.JPG

http://dl.dropbox.com/u/35691595/P3100003.JPG

http://dl.dropbox.com/u/35691595/P3100004.JPG

http://dl.dropbox.com/u/35691595/P3100005.JPG

[blegh]

This is really interesting! Do you have to change the direction of the grain in the strips you are laminating, or no big deal??
thanks

[floatingkiwi]

Alternating grains would only do nothing but good, but I don't worry about it. If I tried to do so, I would probably end up with all the strips lying exactly as they grew anyway.

[wizbang 13]

That is about what I would do too.
A sawzall with a bayonet blade cuts 90% of the frame in10% of the time and mess, IF you can get at it.
If you can laminate the trouble spot a bit thicker, and overlap and taper out the last lams, better. Usually the interior or bilge stringer is in the way.
I would not use oak for the new wood, but Alaska Yellow Cedar, sliced thin that it does not need any wetting /steam. You do not need to wack them in all at once, thin lams, monel staples, easy does it.
I employ LOTS of tooth, (rough the old, freshly exposed oak with a sawzall blade), and use 403 microfibers, not sawdust. That said, I have never used G flex.But I stay away from oak.

[blegh]

All really good to know. Thanks

[BrianM]

Unfortunately I am unable to replace entire ribs in most cases, given that the boat is completely assembled and in sound condition. The covering boards are in great condition and are covered in canvas. I can remove tanks and other equipment to gain decent access, but most of the breaks are at the turn of the bilge, and if there is a proper method to repair this section I would prefer to do that.

I have been told that epoxy and white oak may have some potential issues. Can anyone comment on this??

Facing the same problem, I took a route that satisfied my goals.
Getting access to the frames to sister or replace them requires removal of planks, covering boards, interior, or some combination of all three.
If you don't have good access, the ability to work efficiently drops and the time you have to put in just to repair/replace frames goes way up.
The quality of the job may or may not be your first priority. That depends on the value of the boat, and how safe you feel you and your passengers will be once the fixes are done.

If you fasten laminations which has no glue in them at all with bronze screws, through the planks from the outside, how much strength would that structure have?
I have white oak full length sister frames that are laminated with West System Epoxy and Cabosil (thickener). After 8 years, there is no sign of delamination in any of the 18 sets.
Some people have experienced delaminations in white oak and epoxy. The Gougeon Brothers have information on how to address it.

[Tangusso]

Sounds like a good question. Does anyone have the answer???

[floatingkiwi]

I am not sure what the question is, but not trying to argue with Wizbang, who is more experienced than I, and knows a lot of good stuff, I , and well, we, all have our thoughts on wood and glues etc.
In My experience, epoxy and oak,(oak being the best boatwood available for many reasons) , stick together just fine. I have restored a folkboat from death condition, and I have used WO and epoxy,( Marine 2 to 1 epoxy from TAP plastics, the stuff is good), together in every place where wood and glue members were repaired or replaced. Hell, the entire forefoot is comprised of 10 pieces of WO and maybe 20 percent epoxy, all the frames are laminated the with the same as well as floors all replaced and/or repaired using the combination that if it fails, my boat will come apart at every seam and I shall be swimmingkiwi until such time as somebody comes and saves my Kiwi ass. Most of these repairs are 2 to 3 years old and are good. Although the boat is painfully close to splashing, it hasn't been in the water but extremes of hot and cold and humidity in the air, with effects of such quite apparent, has been considerable where I am and nothing is, nor looks like it wants to ever, come apart.
That is how I see it.
Bruce is right about the grinder taking a long time too. If you do use one there are sanding discs that go onto a grinder with many leaves of sandpaper stacked over each other with their edges exposed in one direction,.I find those extremely effective and they remove wood FAST. Look out.

[blegh]

If you fasten laminations which has no glue in them at all with bronze screws, through the planks from the outside, how much strength would that structure have?
I have white oak full length sister frames that are laminated with West System Epoxy and Cabosil (thickener). After 8 years, there is no sign of delamination in any of the 18 sets.
Some people have experienced delaminations in white oak and epoxy. The Gougeon Brothers have information on how to address it.

I think perhaps you may have misunderstood him. I believe he meant to epoxy the laminates together and to use microfibers in the mix. When it has all cured, then grind/sand/chew it back to the shape of the original frame. Please correct me if I am out of line here crew,

B.

[JoshuaIII]

White oak and epoxy does not go along... Follow Wizbang advice.

Sorry Kiwi but you can’t judge and suggest it while your boat was not even use and your join never stressed over real condition. Gluing it and leaving it in the shed sure will make it hold.

[BrianM]

I think perhaps you may have misunderstood him. I believe he meant to epoxy the laminates together and to use microfibers in the mix. When it has all cured, then grind/sand/chew it back to the shape of the original frame. Please correct me if I am out of line here crew,

B.

Sorry, I wasn't being clear. I meant to say, if the glue fails, then you have laminates that are still clamped together with screws or rivets through the planks and frames. The laminates can't go anywhere with just the mechanical fasteners alone. Gluing certainly improves the strength of the structure dramatically, but losing a bond here and there is academic if you have fasteners in place.

If I were gluing up white oak for something like deadwood, I would not feel comfortable with reliance upon the fasteners alone (assuming glue failed) since the number of parts involved would be high, and deadwood has relatively few fasteners compared to planks on frames.

[LakeErieSailor]

Wizbang, I'm facing the same problem in my Folkboat, and I have also read about the laminating method in Frame, Stem & Keel Repair from our host. What interests me is your comment about using a Sawzall to cut out the broken part of the frame; do you think that I could do the same with a Fein Multimaster?

Regarding epoxy and white oak, at the risk of further fueling the controversy, I have to agree with Kerry, a.k.a. "Floating Kiwi. I built Reuel Parker's Maryland Crabbing Skiff six years ago, and laminated the stem, sternpost, and other components also, all of white oak, with epoxy, and have experienced no delamination. Having said that, I must admit that I also used mechanical fasteners. However, the oak has not delaminated at any point, and the boat is exposed to the weather year-round.

I suspect that the durability of the white oar - epoxy lamination is a function of the moisture content of the oak. Mine had been stored in a barn for 30 years.

[wizbang 13]

I don't know, I have never used a multimaster.
Gluing oak is not a controversy for me. I do not like it for other reasons as well. Poor rot resistance, instability,"blackness". Maybe it is all the dead oak frames I have chopped out of boats, begins to cloud my judgement?
I have glued to it just fine.

[Jay Greer]

As I have mentioned in other posts on white oak West System 650-8 Gflex epoxy is designed to remain a bit flexible and is also designed to deal with oily and difficult woods to glue. This makes it an excelent glue for laminating white oak frames and spars. Whether you decide to scarf in a section into the existing frame or to or along side, riveting the laminated frame is the best approach, when possible, as it adds positive holding power where screws can have a tendancy to separate laminants. When sistering, it is a good idea to taper the head of a frame that does not travel the full distance from keel to sheer in order to lessen the enevitable hard spot it creates.
Jay

[floatingkiwi]

White oak and epoxy does not go along... Follow Wizbang advice.

Sorry Kiwi but you can’t judge and suggest it while your boat was not even use and your join never stressed over real condition. Gluing it and leaving it in the shed sure will make it hold.
I am not judging anyone. I am not saying I am right and anyone else is wrong. I am merely saying it is as I see it, with the factors at hand, displayed proudly and unashamedly, for all ye to peruse at thy leisure, and maketh up thine own mind, yeself.
Are you telling me my boat is going to work itself apart in a seaway?

Inside WO are tiny waxy clumps, called tyloses, that fill out and block up all the miniature corridors of passage in the woods structure, and it is not only water that these phenomena,( found in WO always and only and never in Red Oak)repel, but also are a hindrance to the influx of glues.
If one heats the wood, a dilating and loosening of the fibres allows better intrusion of epoxy , which is furthermore bonded into the matrix by the wood cooling and clamping around setting glue.
If the surface is lacerated and scored deeply,with sandpaper and rasps etc, this also adds beneficial attribute to woods glueing capabilities.
FWIW, This is how I see it..with no rigtht or wrong, just a few thoughts to share with anyone who might possibly be remotely interested. I do hope it works as it is my life on the line..

[LakeErieSailor]

I respectfully beg to differ with wizbang regarding the rot resistance of WHITE oak. From all I've read in the literature, including Dr. Jagels in WB mag, its rot resistance is very high. Rot resistance of red oak, conversely, is not. And there are various grades of white oak also.