Laminating a frame

[Todd D]

When I ripped the interior out of my boat last summer I found eight broken frames in a row. All the breaks were at the turn of the bilge. I am reframing the hull below the waterline, but I decided to beef up the framing where the breaks are by putting in laminated sister frames along side the new laminated frames.

As I have said in previous posts, I laminate wood all the time, but have only steam bent a few small bits for model yachts. Consequently, I find the lamination process familiar and easy. I thought I would do a little photo essay about the lamination process as I do it.

The following pictures and captions describe the proces.

I start the process by either removing the old frame and using that as a pattern of making a pattern from cardboard. I then use the pattern to set up the dogs on my jig. The jig consists of a set of 2x10s lag bolted to 2x4s. The dogs are through bolted to the frame with 1/4" bolts. This first picture shows the stack of oak strips that will be laminated together to make the farme. I have the strips arranged in the stack so the the grain orientation changes from strip to strip. Before anyone asks, yes that is red oak. You can see the clamps and other tools I will use in the background.

http://www.todddunnmicroyachts.com/tortuga/frame_lamination-1a.JPG

The first step is to wet out both sides of each oak strip with unthickened epoxy. I use West Systems 105/205.

http://www.todddunnmicroyachts.com/tortuga/frame_lamination-2a.JPG

Once all the strips have been wetted out, I thicken the epoxy with West 403 microfibers and spread the thickened epoxy onto one side of each oak strip.

http://www.todddunnmicroyachts.com/tortuga/frame_lamination-3a.JPG

You don't need a lot of thickened epoxy on each strip, but I do try to make the layer fairly uniform.

http://www.todddunnmicroyachts.com/tortuga/frame_lamination-4a.JPG

[Todd D]

Once all the oak strips have been coated with thickened epoxy, I put the stack of strips onto the jig and clamp it at the center dog. The first clamp is at the center because the strips won't move relative to one another at that point as the clamping proceeds.

http://www.todddunnmicroyachts.com/tortuga/frame_lamination-5a.JPG

The next step is to move to the ends. I start by putting a clamp on one end and then bending the stack of strips at the other end of the stack as much as can by hand. At that point I put a clamp on that end and tighten it a couple of turns. Because the ends generally have to move more than the screw length on the bar clamps I use, I then add a second clamp and tighten the two clamps simultaneously. Doing the clamping this way, the first clamp reaches its travel limit before the second clamp does. I can then give the second clamp a few turns and then back off and reset the first clamp. At this point there are no clamps between the middle and the ends so that the oaks strips can slip past each other as clamping procedes.

http://www.todddunnmicroyachts.com/tortuga/frame_lamination-6a.JPG

Once I have drawn the ends of the stack of oak strips down the the end dogs, I go back and add clamps at all the other dogs and between the dogs. During this clamping I periodically whack the set of strips with my hammer to keep them all aligned. I also smooth the epoxy that squeezed out from between the strips with a putty knife. The picture below shows the frame with all the clamps in place. These sisters are 3' long and I have used ten clamps. I have laminated frames up to 12' long this way using about 40 clamps. I am working outside in approximately 50 degree temperatures right now, so I will leave the clamps in place for about 24 hours.

http://www.todddunnmicroyachts.com/tortuga/frame_lamination-8a.JPG

This picture shows the frame I just clamped up as well as one I laminated yesterday.

http://www.todddunnmicroyachts.com/tortuga/frame_lamination-7a.JPG

When I have a few frames laminated, I will run them through my thickness plane to remove the excess epoxy. After that I will paint all surfaces of each frame with three coats of Interlux BilgeKote.

[EastCoastChris]

Todd,

Thanks for taking the time to do this, I for one find step by step threads really helpful. Looking forward to the next installment :D

Chris

[Todd D]

Forgot to mention how long this takes. Laminating a frame this way typically takes 20-30 minutes from the time I start mixing the epoxy. This one took a bit longer because I stopped periodically to take pictures. That slowed me down because I had to remove the glove on my camera hand to avoid coating my camera with epoxy. Actually the planing and painting of the laminated frames takes longer than the actual lamination. Another chunk of time is spend in rewawing the oak from the 8/4x6 pieces I start with into the strips. I am making my frames 1-15/32" thick using five strips, so each strip is a bit under 5/16" thick.

[pcford]

You do understand that it is generally agreed that epoxy will not reliably glue white oak. Some specialty epoxies do claim that they can; however, that is not what you used.

There are any number of discussions on this topic on this forum.

[Todd D]

Mr Ford,

Indeed I am aware that glueing white oak with West 105/205 is considered by some to be unacceptable, while others claim not to have had any problems. However, near the top of my post I said "Before anyone asks, yes that is red oak." The epoxy I am using seems to glue it very well. Now many people will say I shouldn't have used red oak, but I am sticking with what the local wooden boat people told me - it is good for 30+ years around here.

[Bill Griffin]

Thanks, Todd, for starting this thread. I've found that I'm looking at replacing 20 or so frames, maybe more but I hope not. I don't plan on using either red or white oak though. The step tutorial will be a helpful addition to our hosts book on the subject. It's easier for me, at least, to see a bending table in use, to understand how to set it all up.

[Todd D]

Bill

I replaced 30 frames this summer. I found that removing the old frames and repairing the planking was most of the work. My boat was originally iron fastened and then sometime later refastened with bronze. The result was that the iron boat nails totally disintigrated and took the frames with them. The damage was limited to below the waterline, so I am replacing all the frames below the waterline by scarfing in new laminated frames. In the process I removed all the iron fasteners and repaired the planks where they were damaged by the iron. I also bunged all the holes where the bronze fasteners were.

When I started, 20 frames would have seemed like a big job, but now that I am well into the job (seven frames to go), 20 frames doesn't seem like much. It is rewarding work though.

What is your boat?

[Bill Griffin]

Todd,
She's S&S design #81, a 30' fractional sloop. I have started a thread below titled "Oh My" as a humorous reference to the "Oh Joy" thread, and as what I foolishly thought was going to be just replacing the cockpit sole has turned into a bit more.
The builders plate tells me Allegro was built by Kretzer Boat Works, on City Island, in 1935. I'll be replacing the entire frame on the broken ones, and some floors, and some refastening, and replacing the fuel tank, all just for starters. Oh yes, it looks like the engine will have to come out to manage some of these repairs, as well as the cabin interior. I'm wondering what else I'll find!
I haven't had a chance to do much more that get the soggy bits out.
I have some time off coming up, and hopefully can get at it again.

[RFNK]

Thanks for this Todd! I'll be replacing around 12 pairs of frames soon in my Twister (see Restoration of a Twister thread). I'm also hoping that for many frames I'll be able to use the old one as a pattern but I suspect that they'll sping out a little as they're removed as the turn into the bilge is quite tight, so I'll have to set up a spiling board instead. Also, I'll be using thinner strips because of the tight turn and will have to plane the underside quite a bit to pick up the planking angle. For this reason I'll keep the lower strips at least with the grain running in the same direction. I'll also post some pictures when I do it, if I don't stuff it up too much of course! Rick

[George Roberts]

I would expect that one would use the hull side of the frames as a bending reference.

Also for those working in warmer temps, get your work done before the epoxy gets too far along.

[shamus]

Interested to see you wetting out with the foam brush. When I was doing quite a lot of epoxy work at one time I tried foam brushes and found that they started leaving blobs of the foam in the glue very quickly. They must vary in quality I expect- wish I could find some here that would work.

[Rich VanValkenburg]

Looks like a good, well thought out job. I won't criticize because you're getting good results. I'll just offer some suggestions that may save you some time.

I used dogs for my latest thing, a fireplace surround for an arched door, but not for Sonja's 27 pairs of frames. What worked best was 3/4 ply as a form. This allowed me to buy one sheet of ply and have some left over. I made the frames that had the most bend first, and then band-sawed the form down to the next frame pattern. It lets you use the same pattern stock over and over again with the slight variation. Deflection after unclamping was minimal. Big frames were clamped to a form that was cut from two or three pieces and screwed together with drywall screws. Using ply as a form also lets you use as many clamps as you need, not just where the dogs are located.

The glue looks a bit thick, you want it looking and acting like Honey. Add the 403 a little at a time to get to that consistency.

I used foamies at first, but found I could use a cheap 1" chip brush and then clean it with denatured alcohol. One brush got out several frames. I had a whole box of these that I ordered from Jamestown but still had over half a box left when the frames job was finished.

Like you, I used the thickness planer and router with a 1/4 round over to make 'em look nice.

The Red Oak is fine. I encapsulated with a couple coats of unthickened epoxy and a couple coats of urethane varnish but paint works just as well. Make sure the ends are well sealed or they'll delaminate. (ask me how I know):rolleyes:

http://i115.photobucket.com/albums/n287/falcon5a/rib3.jpg

http://i115.photobucket.com/albums/n287/falcon5a/rib5.jpg

[Todd D]

Rich thanks for the comments. As far as the thickened epoxy goes, yes it is a bit thick, but that is intentional. I put quite a liberal coat of unthickened epoxy on the strips, which then mises with the thickened epoxy to make the right consistency. The plywood pattern/jib looks like a good idea, but I think your frames are a bit less beefy than mine (1.5"x2"). Consequently, I think a ply jig would have to be quite thick to take the strain without deforming.

I am not a fan of chip brushes. Everytime I have used them I find that I get bristles in the work that I feel obligated to pick out. I also don't really like to use and then dispose of the solvents needed to clean brushes I use the JEM foam brushes and find that they hold up quite well. I use a lot of them and get quite good prices.

George, I do use the outside of the frames as the reference. However, after clamping a few up on the other side of the dogs, I have found that is is much easier to do the clamp up on the outside. Furthermore, these frames have to be beveled on their outsides, so a bit of error at this stage doesn't matter.

[chuckt]

This is probably a dumb question: When you bend wood without steaming it, doesn't it retain a strong desire to spring back? I know the epoxy is really strong. Do things like this stay in shape? Are there some rules of thumb on how far you can just bend wood w/o steaming? I know it will vary by specie and thickness

[Mrleft8]

Laminated bends (Frames in this case) do not want to spring back, unless you use too few lams. I generally try to use 5 lams minimum, and if possible, always an odd number.

[Rich VanValkenburg]

Laminated bends (Frames in this case) do not want to spring back, unless you use too few lams. I generally try to use 5 lams minimum, and if possible, always an odd number.

I'd never heard of the odd number of lams. Is there more strength with that technique? That's something to remember.

I didn't have any springback with the frames but I did have 3/4" springback with the mantel surround. I steamed the frames and let them dry in place a coupled days but not the mantel. I've got no explanation. Maybe it's the glue. I used ordinary carpenter's glue for the mantel and either Weldwood or epoxy for the frames, depending on my mood.
http://i115.photobucket.com/albums/n287/falcon5a/Misc%20non%20boat/Mantel002.jpg

[Mrleft8]

An odd number of lams equalizes the forces on either side of the central lam. I use yellow carpenter's glue for 90% of my laminations, including veneering. When I laminate boat parts, I use epoxy. (I know, I know....."White Oak blah blah blah"...:rolleyes:) I'm not sure why it's best to equalize the forces on either side of a central lam, as the glue holds the lams from sliding along eachother's length anyway, but it does seem to make a difference.

[willmarsh3]

I've laminated frames in this manner using douglas fir and southern yellow pine. There was always minimal to undetectable spring back. My laminates were about 3/16" thick and I used 7 to 14 laminates.
The Gougeon Bros book on WEST system has a formula for strength of these laminates based on the thickness and number. IIRC the evenness or oddness of the laminate count doesn't enter into it at all.

[Rich VanValkenburg]

(I know, I know....."White Oak blah blah blah"...:rolleyes:)

Something I just learned at the Detroit EBS (yep, we did more than just eat and drink) is that White Oak is ok with epoxy as long as you don't plane the lams smooth. Bad memory means I can't credit that info. Rough cut lams have more tooth area for the epoxy to grab onto. White Oak is so dense that you don't get the absorption that you need so you have to give it some tooth. That came from the Gougeons I think. I've always planed and high-pressure clamped them with Weldwood, something you don't want to do with epoxy. I guess I goofed.

[Todd D]

I took the frame I showed being laminated off the jig this morning after 23.5 hours. There was no springback at all.

I also use the strips as they come off the table saw. Again, that is intentional so that there will be lots of tooth for the epoxy to grab.

I am going to run a couple of frames through the plane later today and then put the first coat of paint on them. Pictures will be added to this thread this evening.

[Todd D]

After the epoxy is cured I clean the frames up by running them through the surface plane to get rid of excess epoxy. This picture shows the two frames I am working on right now ready to go through the plane. You can see the excess epoxy on the surfaces.

http://www.todddunnmicroyachts.com/tortuga/frame_lamination-9a.JPG

Here are the two frames after the excess epoxy has been planed off.

http://www.todddunnmicroyachts.com/tortuga/frame_lamination-10a.JPG

And here are the two frames after the first coat of Interlux BilgeKote. I will put three coats of paint on them before I install them.

http://www.todddunnmicroyachts.com/tortuga/frame_lamination-11a.JPG

[pcford]

Something I just learned at the Detroit EBS (yep, we did more than just eat and drink) is that White Oak is ok with epoxy as long as you don't plane the lams smooth. Bad memory means I can't credit that info. Rough cut lams have more tooth area for the epoxy to grab onto. White Oak is so dense that you don't get the absorption that you need so you have to give it some tooth. That came from the Gougeons I think. I've always planed and high-pressure clamped them with Weldwood, something you don't want to do with epoxy. I guess I goofed.

I'm in a crappy mood today and I might as well take advantage of it:

One of life's little annoyances is reading this theory about planer glaze being the source of problems with white oak. And one sees it fairly regularly.

Professionals have been aware of this problem with gluing white oak with epoxy for about...oh, thirty years. Why do people insist on thinking that they have made some breakthrough when they advance the theory that all will be well if the white is sanded before gluing?! Do they think that those that are reporting the problems are so lame that this would not have occurred to them?! jeebus.

A West salesmen went on at length about improper prep being the problem, not something else like the high acid content. The salesmen was sporting a mullet 'do...a sure indication of sub-par intelligence...while he raved about boatswrights being the bane of his existence. He later sent me test results from the West lab that....confirmed that there is a problem with white oak and epoxy.

I think the problem is the acid content of the wood...just my theory. But it is certainly not planer glaze and the lack of a suitable surface.

There have been epoxies formulated for white oak...one might presume therefore that there is indeed a problem.

The original poster wrote: "Now many people will say I shouldn't have used red oak, but I am sticking with what the local wooden boat people told me - it is good for 30+ years around here."

My god, you can blow through a length of red oak a few inches long!! Can you think of a better environment for rot? Your advice from your "local wooden boat people" notwithstanding, I think red oak will rot in Maine as well as it does elsewhere.

And other thing...I'm on a roll now....

I think laminated frame are fine in small boats which are kept out of the weather. I have seen guideboats built with laminated frames instead of the original crooks. But for larger boats which have to endure moisture cycling...I cannot see the advantage. Just put in steamed frames.

There might be some applications where you might have to put in laminated frames in a larger boat, but these are mighty rare, in my humble opinion.

Finally, doing laminated frames is nasty work. (Yes, I have done them.) Steamed frames are so much neater and faster. And I believe a recent post demonstrated that there is not a strength advantage to laminated frames over well produced steamed frames.

So...to return to the original poster...it seems like he has taken the long way around to get an inferior result.

Your mileage may vary.

[George Roberts]

If I was having a bad day, I would agree with pcford.

[Vinny&Shawn]

I also have to agree with pcford on all accounts,maybe 30 years with red oak is not a long time in wooden boat life. Therefore our boat at 26 would be nearing a rebuild. While there are turn of the century boats still alive and ready!

[pcford]

I also have to agree with pcford on all accounts,maybe 30 years with red oak is not a long time in wooden boat life. Therefore our boat at 26 would be nearing a rebuild. While there are turn of the century boats still alive and ready!

Look, it's basic that red oak is inferior for this use. In WoodenBoat issue 2 or 3, John Gardner addressed this problem. He suggested that you could use red oak's porosity to your favor by soaking in preservative. For laminated frames this is not a good possibility.

But why use red oak anyway? At least here there are both the same price. It is entirely possible that red oak may have lasted a generation in your boat. Would I bet on that occurring for the next guy? Nope.

Again, it's the long way around to get a substandard result.

[Bill Griffin]

OK, I'm not disagreeing with anyone here, but I can't help note that a couple threads above this Luke is building a 72ft. schooner with laminated frames. Are we just talking materials--i.e. red vs. white oak, or what? If the repair lasts decades, does it really matter if it's steamed or laminated? And I understand there may be a difference in strength, but just how much of a difference? I notice Paladin states he used laminated for a circ, or two.
Ducking out now!

[Tom Robb]

I think I'd be seriously disapointed if I put in the effort to build, or rebuild, a 72' boat and got a 30yr lifespan. But that's just me.
Reading through this thread, the old saw, "you can lead a horse to water, but...." kept wandering through my head.

[Todd D]

Well I for one am willing to live with a repair that holds up for 30+ years. If the boat lasts that long I will be over 90 and I suspect that I won't really care if the boat falls apart then.

Incidentally, I looked for whire oak in the local lumber yards and just didn't find it. I asked if I could order it in. When the answer was yes, which was infrequent, the minimum quantity was a LOT more than I needed. So I went to the local wooden boat builders and asked for their advice. The people I asked are very well thought of and have been in the qooden boat business for 40+ years in one case and 50+ years in the other. I was told that laminated red oak would do just fine. That is why I am using the wood I am. I can get it at places where I can select each piece myself.

It would be nice to live in a big city where everything is readily available. Unfortunately I don't live in a place like that.

[RFNK]

For goodness' sake! Has pcford never looked at any yachts with steamed frames and a tight turn into the bilge? Has pcford never seen laminated frames over 30 years old? Show me a 30 year old yacht with steamed frames and a tight turn into the bilge and I'll show you all the broken steamed frames. Builders have been successfully laminating frames using a variety of adhesives for a very long time. The suggestion that laminated frames are not a good option for larger yachts is simply ridiculous. Rick

[pcford]

Builders have been successfully laminating frames using a variety of adhesives for a very long time.

Really?

And by the way, we were talking about laminated frames of red oak, a notoriously rot prone wood. White oak can be glue with some success with resorcinol. Other woods, mahogany for example, can be glued with epoxy. And...I have glued frames up with mahogany and epoxy. It is nasty but can be done successfully.

It is possible to do correctly...based on the experience of others over time...that, after all is the basic building block of traditional boatbuilding.

[RFNK]

And other thing...I'm on a roll now....

I think laminated frame are fine in small boats which are kept out of the weather. I have seen guideboats built with laminated frames instead of the original crooks. But for larger boats which have to endure moisture cycling...I cannot see the advantage. Just put in steamed frames.

There might be some applications where you might have to put in laminated frames in a larger boat, but these are mighty rare, in my humble opinion.



Pcford, I assumed you were making a general statement about laminating frames. I have no comment about or knowledge of red oak. Rick

[Rich VanValkenburg]

I also read about the porosity of Red Oak and I think Todd is making an effort at sealing the frames to keep the water out, also the glue will help but not stop same.

I won't argue the point, you sometimes have to use the materials available and do what you can to protect it. Years ago I was surprised to find out that the schooner Heritage was framed in Red Oak after all I'd read in early issues of WB. Maybe the captains of that vessel have something to say about it.

While I'm at it, I'll dig for the comments about non-planed White Oak vs. planed and see where that came from.

[Bob Smalser]

......white oak with West 105/205....while others claim not to have had any problems. However, near the top of my post I said "Before anyone asks, yes that is red oak." The epoxy I am using seems to glue it very well. Now many people will say I shouldn't have used red oak, but I am sticking with what the local wooden boat people told me - it is good for 30+ years around here.


Don't sweat the small stuff.

Red Oak is a different wood entirely from White Oak, few woodshops have had trouble gluing it using any glue, and when they do the problem is usually moisture related.

Plus you aren't talking about replacing a ceiled, poorly-ventilated frame in a large yacht destined for the tropics.....you're talking about the same small boat frames builders have successfully used equally rot-prone ash, spruce and elm for across centuries. Insure air, light and drainage in what you can see, and intact bedding in what you can't, and those woods can enjoy excellent longevity in cold climates.

Other than that I prefer five lams to four. Although should I run out near the end I don't always practice what I preach.

[Todd D]

Hi Bob,

I know it doesn't show well in the pictures, but I am using five laminations.