Steaming Oregon

[AussieBarney]

:pHello Every body, I have some questions about steaming timber. I am using old oregon, Known as douglas fir in the U.S.?? to make inwales on my garvey. I'm using this because I have it and I am working with virtually no funds. I have followed several threads on how to steam, how to set up the steamer and so forth. I am thinking of steaming 75x25mm (3x1in) pieces 12 feet long. My questions are:

how long a time do I steam for?
When I get the timber clamped into place, do I glue it then or do I wait for it to dry and then take it off, apply glue and reposition?

I am sure that someone can help Please!!!!
Please remember Peter from Canada calls himself Ten Thumbs. I call myself "No thumbs Barney":o:confused::D
Regards Barney

[Wild Dingo]

Just a wee bump Barnie :cool: ...rather let the hexamasperts comment ;)

[Bob Smalser]

how long a time do I steam for?

When I get the timber clamped into place, do I glue it then or do I wait for it to dry and then take it off, apply glue and reposition?



DF will only bend to a radius of 18" with steam. It's very stiff.

For 1" thick I'd start with 20-30 minutes of good steam then try it. Then use increments of 10-15 minutes for any further steaming. But wales should go in with only light steaming. Insure they don't have grain runout in either surface.

If the pieces are to be glued, after steaming clamp them into place overnight so they take a set then remove them to glue. If you steam correctly, keeping your stock off the condensation on the bottom of your box, they won't be any wetter than when you started.

[JimD]

You could do a lot worse than having old doug fir to build a boat with - marvelous wood and wish I had more laying around. But like Bob says it doesn't bend all that well. Choose your grain carefully. It doesn't take much grain runnout to create a weak spot where it will break. As long as you're going to glue it consider thinner strips that will bend easier and laminate very well with epoxy if you don't have great luck steaming it.

[Yeadon]

I'd be tempted to first bury it in water and soak it for a couple days, then try to bend it inside the curve of your sheer. If that doesn't work, then I'd just steam the end where the harshest turn is located.

The formula for steaming ... a half hour for every inch of thickness? Anybody? If the stuff is dry then I'd be very conservative.

You have a photo of your garvey? How wild is this sheer?

[Bob Smalser]

It's heat that makes lignin pliable, not water. Plus you don't have very far to bend. Soaking will do nothing for you except make your wood too wet to glue.

Soaking is often used because moisture in the wood transmits heat well, not because the wood needs more water to bend. That can be important bending 3"-thick oak frames. It's not at all in thin fir.

[Thad]

My experience bending fir includes multiple occasions when pieces seemed to bend in fine (cold and steamed) but later, sometimes within hours and sometimes days, there would be a bang and the piece would have broken. It is possible that there was runout in each case but if so the runout was very minimal. Stiff he says.

[pcford]

It's heat that makes lignin pliable, not water. Plus you don't have very far to bend. Soaking will do nothing for you except make your wood too wet to glue.

Soaking is often used because moisture in the wood transmits heat well, not because the wood needs more water to bend. That can be important bending 3"-thick oak frames. It's not at all in thin fir.

Have any actual experience you could cite? If the stick is dry or KD I prefer to toss in the lake for a few days.

[Rick Tyler]

A friend and I blew out three pieces of 1x2 (roughly 25x50mm) CVG doug fir putting the gunwale strips on a drift boat. We then soaked two new sticks for a week in a PVC pipe full of water, clamped them on the sheer to dry for a week, and then permanently mounted them. It took two weeks, but neither of the soaked strips blew out. I would NEVER pretend to know more about working with Northwest woods than Bob does (really), but in this case soaking worked well. We didn't try steam.

[5.5 Meter]

It’s the heat not the water, water transfers the heat.

To all…whatever happened to experimenting? Plus always cook more then you can eat….I mean steam more than you need. Said another way, run out may be an issue, but you may be surprised.

I’ve done a lot of steaming. From 2”x 3”x 18’ oak frames to 1” x 3” oak for a cockpit coming that was bent to a radius of about 8” to 1”x1” ash for frames for a 5.5 meter over a hundred for a 30 foot boat (6-inch centers).

Started out with the mantra that you hear. “Have to use green lumber” and I will currently steam anything including kiln dried. If it’s dry you just keep it in longer. How do you know if it is cooked? Pull it out and give it a try. Snap…opps needs to cook more.

I used to try and really watch the grain run out but often found that the ones that I thought would be the best broke and the ones that I did not thing were gong to last are now on the boat. I will watch the run out to some extent with respect to curve, on a tight curve, if I have a mild curve at the bilge stringer and a tight curve going into the bilge/keel, I’ll have the area with more run out at the less curve area.

Typically I’ll steam 8 blanks for 6 good ones. Don’t be afraid to experiment! Just watch the steam it is hot and can burn…you’ll learn remember that after you reach in to the box without a glove on…it only takes once to forget.

So if I was gluing I would not soak and would love to start with kiln.

[5.5 Meter]

A friend and I blew out three pieces of 1x2 (roughly 25x50mm) CVG doug fir putting the gunwale strips on a drift boat. We then soaked two new sticks for a week in a PVC pipe full of water, clamped them on the sheer to dry for a week, and then permanently mounted them. It took two weeks, but neither of the soaked strips blew out. I would NEVER pretend to know more about working with Northwest woods than Bob does (really), but in this case soaking worked well. We didn't try steam.

You did not cook them long engough...you should see how limber a 2 x 3 piece of oak can get :)

[Bob Smalser]

Have any actual experience you could cite?

Oh, I have a passing familiarity with using Douglas Fir in boats. As Thad points out, it is sufficiently stiff that even laminations are best steamed and clamped in place overnight before gluing.

http://pic20.picturetrail.com/VOL12/1104763/8408305/113221960.jpg

http://pic20.picturetrail.com/VOL12/1104763/8408305/329355471.jpg

http://pic20.picturetrail.com/VOL12/1104763/8408305/310983859.jpg

I won't bother to cite the dozen or so texts and WBM articles that have gone to great length to demonstrate that it's the heat, not the water, that causes wood to plasticize. Water is only one means of many to facilitate getting the heat to the center of the stock. Sometimes soaking is useful, other times it's a waste of time and effort. If gluing's not a factor you won't get into trouble soaking. Just remember that like steaming, because Norm and the furniture crowd rarely deal with it, few out there really understand that gluing wood above 10% MC becomes problematic. And your soaked DF may be much higher than that.

And if then there's any doubt, then peruse these references for bending walnut gunstocks mounted to expensive shotguns without ruining the finish:

http://www.helstongunsmiths.com/stockjig.gif

The entire gun is placed in a special-made jig, the stock's wrist is wrapped in linseed-soaked rags and heat lamps are applied until the stock bends under pressure from the jig. No water is used, and the stocks are left at their usual 6% MC. Soaking instead would be disastrous.

http://www.sportingclays.net/forums/thread.cfm?threadid=1828&messages=6
http://www.trapshooters.com/cfpages/thread.cfm?threadid=138134&messages=5
http://www.briley.com/index.asp?PageAction=Custom&ID=17#11
http://www.allemsguncraft.com/repairs.htm
http://www.helstongunsmiths.com/tr_tools.html

Last, the subject of the thread is a 12' wale with perhaps 12" of bend across 1" of thickness on a radius of several feet, little or no twist, and 2-4" of sny across 3" of width and another large radius. The only reason to steam the stock at all is the sny. Soak it for a week ahead of time and all you've accomplished is wasting a second week until it dries out sufficiently for gluing.

http://pic20.picturetrail.com/VOL12/1104763/9745605/322118700.jpg

Here's a 1X2 DF inwale on a similar, 12' boat. No steam was required, but I recall regretting not firing up the box as I had to apply boiling water to bring the last bit of sny home with serious clamps.

And I sure bet those DF stringers and the heavy DF chines behind them required some steam, eh?

http://pic20.picturetrail.com/VOL12/1104763/9745605/138774735.jpg

[AussieBarney]

Thanks heaps lads, I dont know what I would do without the genorous sharing of experience on this forum. The oregon I am using came out of some 2x8 beams that came out of a house that was about 70 years old. I have already offered up the peices to the boat dry and I can spring it into shape with a fair bit of effort. I just want to be able to do it easily so that I dont introduce a stress into the sheer. With a bit of steaming I thought it might go in easier. I will post a picture of the hull when my teenage son rises from his sleeping swamp.:o:eek: He knows how to post pics, I dont
Again, thank you for sharing your knowledge. I appreciate it. Barney

[boatbear]

I haven't steamed oregon (DF), but have steamed a fair bit of kiln dried hardwood (Vic Ash). Something I found by experiment is that steaming for too long can be detrimental. Now I test after 10-15 minutes to see how rubbery it is. For a 25x25mm stick, 15 mins is about perfect and it seems to go stiff again if left for 30 mins. Dunno why.

Guitar and violin sides, and violin bows are all bent using dry heat. They go rubbery very quickly and set their shape very quickly on cooling.

[Bob Smalser]

So, did Wes and I get lucky with those last two DF sticks that didn't break when we bent them on the drift boat? After a week's soaking and a week clamped on the sheer, when we took them off they remained bent (although there was some spring-back). We screwed-and-glued them back on and they're still there today. Just trying to figure out what happened...

Thanks,

Rick

Airdried wood in equilibrium with local humidity steambends just fine without soaking. For DF that means around 12% MC. Rarely much lower, often higher. "Kilned" wood in DF is usually kilned to only 19% as framing stock, and is actually wetter than airdried. Wood destined for cabinets is kilned to 7-8% and may benefit from some soaking, and wood destined for floors is kilned to 4% and definitely requires rehydrating. Wood converted for cabinet and flooring use is not common in DF....most is converted for framing stock.

http://pic20.picturetrail.com/VOL12/1104763/3075040/53116512.jpg

If your success is hit or miss, the problem is most likely grain runout. Mills do a good job preventing grain runout in one dimension (edge or face) but a lesser one in the other if there is any taper to the log. You have to evaluate bending stock for grain runout and correct for it. When you can't see the grain easily, an awl of felt tip pen can often find the true grain rather than the wood's figure.

http://pic20.picturetrail.com/VOL12/1104763/4518261/56509953.jpg

[onobleboat]

The last Douglas Fir I bought for a deadwood piece was excellent quality but had 100 splinters in my fingers from unloading it. Red Florida Cypress is almost the same quality, if you can find it and will take a nice curve in the sheer without steam. Just a thought.

[pipefitter]

I bent 1x3' (3/4"x 2-3/4") clear DF on the inwales/coaming of my skiff. I bent it dry and it was kiln dried. I wanted the tension for prestressing a monocoque structural component, with a pronounced sheer profile as well as generous flare so it was a compound curve and the shape was out of fair overall by design. It is also glued and cross fastened so it can be done. I had to alternately fasten and sneak up on it with the screws and bar clamps.

[AussieBarney]

Yeadon,http://i298.photobucket.com/albums/mm246/AussieBarney/boats048.jpg Here is the photo of the sheer on my garvey. As you can see it is not too wild, I am just trying to relieve the stress the inwale has. maybe I shouldn't? Ideas anybody? I have got a little further down the line than this pic shows I'm going to post a progress thread when i get the next job finished. regards Barney

[Clencher]

I have to agree with Boatbear here;

"Something I found by experiment is that steaming for too long can be detrimental. Now I test after 10-15 minutes to see how rubbery it is. For a 25x25mm stick, 15 mins is about perfect and it seems to go stiff again if left for 30 mins. Dunno why."

I've had exactly the same experience steaming European oak, and Iroko. Steam or boil it too long and it seems to go back to its brittle state. I dunno why either - would be interested if Bob S has a comment on this.

[Mrleft8]

The last Douglas Fir I bought for a deadwood piece was excellent quality but had 100 splinters in my fingers from unloading it. Red Florida Cypress is almost the same quality, if you can find it and will take a nice curve in the sheer without steam. Just a thought.
I sure wish I could bend wood with the power of my mind, but I haven't even been able to move a salt shaker by telekinesis yet... ;)

[paladin]

I cheat....I use a thin kerf blade and make everything slices maybe 1/8th to 3/16ths thick, slather it with epoxy, cover the area to attach to with saran wrap, clamp the epoxy strips to the area and let set.....when the epoxy goes off, remove the clamps and clean up the nice curved piece of wood, then finally fasten it where you wanna....I also have a tendency to build up gun'ls with Philippine mahogany, but then cover the exposed edges with a thin strip of Honduras epoxied in place....

[tonydezoc]

I thought I’d add my 2c worth here, Firstly I usually steam wood for 20 minutes per square inch cross section , make sure the steambox is secure and doesn’t leak too much so the wood gets good and hot. For dry wood I have always soaked it first if possible and always felt that this helped with the exception of oak that was to be varnished as I found the soaking caused too much staining. Most of my boatbuilding has been the traditional sort learned from other older builders and very unscientific so I am in awe of a few of the regular posters here ( Bob Smalser being one, Todd Bradshaw another) because of their technical knowledge. I have never steamed and then glued wood but there are glues that seem to prefer slightly moist wood, don’t know exactly what the name is (polyurethane ?) the ones that foam up as they cure and need high clamping pressure . As for over steaming wood I have always thought that this led to drying out the wood and caused it to be brittle. I shudder to think what the purists might think of this but years ago I worked at a yard where we were re-planking a hull and the wood arrived freshly milled and still moist, we couldn’t just stick the boards and wait for a year so we rough cut planks, steamed the s**t out of them clamped them to the boat and left them for about a week before fitting them the idea being that the oversteaming would essentially kiln dry them, It seemed to work and I don’t recall there being any problems after, the wood was African mahogany.

[Bob Smalser]

Steam or boil it too long and it seems to go back to its brittle state. I dunno why either - would be interested if Bob S has a comment on this.

Notice above I recommended checking 4/4 stock after 20 minutes in the box rather than the longer periods usually recommended, followed by 15 minute increments between further checks. Overcooking it destroys the lignin instead of making it pliable, making the wood both brittle and the first stick in the boat to rot.

A couple other notes based on no practical experience with DF to speak of:

Kerfing the bending stock by resawing through the length of the bend halves your bending problems without reducing strength. One of the smartest ideas in boatbuilding.

Unless you're gonna glue it, prime your bending stock before bending with red lead. Doesn't interfere with steaming and provides better protection to the faying surfaces, especially that bending kerf.

Not being anal about checking and correcting grain runout makes for frames that eventually crack without explanation.

Pulling really tough ones in dry with clamps creates boat members that can crack on you three days or three weeks later. Some woods assimilate to their new stressed environment easily. DF isn't one of them.

[onobleboat]

From the pic I saw posted, there is no need to steam anything, that shear line will take rail easy, cut out the knees from solid wood, if your puting in ribs, saw them out. No need to steam.
You got it backwards here, the sheer will almost never make the fair curve you want, if the inwhale is put in in one piece it will pull the sheer into a fair line, the harder it is to bend the better the sheer line will be, on a scale of one to ten on bending the inwales you have a one, you want to see a ten? Took me two days to get these on, no steam.

http://www.freewebs.com/onobleboat/
http://www.freewebs.com/onobleboat/wherry%20in%20water.jpg

[Yeadon]

I just realized .... days later ... your inwhale is going to be 3"x1" ... that's a hefty inwhale. Hurkin big. That'd be a tough bend along any type of sheer short of a big square punt. If I stuck with a scantling that hefty, I'd probably want to steam it, too. (This is what the plans call for?)

Onobleboats' inwhale is probably something like 3/4 x 5/8, or something rather light. It probably flexed in like a batten.

Just for fun, you should steam one in, and just soak the other in the lake. But I'd mill a third rail and have it standing by, just in case.

[pipefitter]

I suppose I should add that I have plywood sheer decks that were installed beforehand and knees glassed into the hull every 16". The DF was installed under the plywood which was allowed to overhang the knees ends by 11/16ths". The plywood helped capture the stress on the 1x3's on edge and they were straight grained. It also straightened out any warping of the plywood between the knees. It's much of the reason the boat could be built without frames.
http://home.earthlink.net/~tigmaster41/sitebuildercontent/sitebuilderpictures/small22_img.jpg

The coaming strips atop the sheer deck were done as a split lam, creating a sandwich with the ply sheer deck and the 1x3 under it. The 1x2 for the coaming strips were ripped on center on a bandsaw to the angle that makes both outside edges plumb. This allowed 1 rip cut at the set angle and the pieces were then just simply reversed before being reassembled, creating the parallelogram that makes the inner and outer faces plumb with the build designated by the arc of the transom and the sheer deck. The whole structure was then glassed from the interior face, continuous to the bottom edge of the rub rail. If you look closely, you can see the glue line down the center of the coaming strips where the 2 factory edges were glued together.

http://home.earthlink.net/~tigmaster41/sitebuildercontent/sitebuilderpictures/jan29e.jpg


I cheat....I use a thin kerf blade and make everything slices maybe 1/8th to 3/16ths thick, slather it with epoxy, cover the area to attach to with saran wrap, clamp the epoxy strips to the area and let set.....when the epoxy goes off, remove the clamps and clean up the nice curved piece of wood, then finally fasten it where you wanna....I also have a tendency to build up gun'ls with Philippine mahogany, but then cover the exposed edges with a thin strip of Honduras epoxied in place....

If this is a glue build, it is really more cost effective to do as paladin suggests than to experiment with mixing steaming and the learning curve that goes along with that for such limited number of parts. Being you most likely already have epoxy on hand for other parts, it can be easier to laminate the pieces and would be more in step with the other processes in the build. You might even possibly get away with 2 layers of 3/8" or 3 layers of 1/4". DF is an excellent timber for glue lams.

[AussieBarney]

I'm going to post a later pic of my project to give you an idea of what I have done so far. I want this boat to be bullet proof so I am prolly going to over engineer it to hell and gone:rolleyes::o. Give me a couple of hours to work out the prayers and incantations to the gods of the computer and it will appear:D Barney

[5.5 Meter]

Notice above I recommended checking 4/4 stock after 20 minutes in the box rather than the longer periods usually recommended, followed by 15 minute increments between further checks. Overcooking it destroys the lignin instead of making it pliable, making the wood both brittle and the first stick in the boat to rot.

A couple other notes based on no practical experience with DF to speak of:

Kerfing the bending stock by resawing through the length of the bend halves your bending problems without reducing strength. One of the smartest ideas in boatbuilding.

Unless you're gonna glue it, prime your bending stock before bending with red lead. Doesn't interfere with steaming and provides better protection to the faying surfaces, especially that bending kerf.

Not being anal about checking and correcting grain runout makes for frames that eventually crack without explanation.

Pulling really tough ones in dry with clamps creates boat members that can crack on you three days or three weeks later. Some woods assimilate to their new stressed environment easily. DF isn't one of them.

Allow me to clarify.

Unless you are working with Sitka (of which I doubt anyone would use for frames) there is now way you will get away from some run out. You may be fortunate to end up with a piece where the run out ends up being the entire length.

So let me clarify. You will want to look at it within reason, if you have a piece say 10 feet long and the run out is two feet then I would not even bother using it for steaming. But if you have a 10 foot length and the run out is 8-feet then steam it or as we like to say “cook it”. I have spent a lot of time looking for the perfect pieces to steam and more often than not the piece that I thought was the best broke while the one that was of doubt held.

Experience has also shown to me that if it survive the steaming, breakages is usually associated with none run our reasons, ie: fastenings.

[onobleboat]

Went into the spare closet and dusted off the spider webs, found two sets of garvey plans from John Gardener. Are you working from plans? His inwhales on the garvey were 6 x 1 which is not an inwhale but a coming, designed to keep water out of the boat, still no need to steam, will pull in no problem.

[CundysHarbor]

I have been building a boat that required steaming of some of the strips. They are 3/4 x 1 3/8 white cedar. I did this using a long plastic bag (bought a roll of 1300 feet on EBAY) and a wall paper steamer. The strip was clamped to the boat and the bag eased over the strip. In my case, I was just steaming the last 12 feet. I inserted the steam hose a few feet into the bag and started the steamer. It was best to clamp the bag almost shut on the uphill end and let the condensate and steam exit the hose end. In 15 minutes after the first steam entered the bag the strip was noodle-like. I started by clamping the strake and bag to the boat but found that drying took forever. Ultimately, I stripped the bag, clamped the strake and let it dry for 24 hours. After the wait, moisture level was back to 12 and the strake could be epoxied in place.
Dave