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davebrown
05-04-2012, 01:26 AM
I'm at the last stage of my coquina build. Seats are going in Sunday. Next week will be paint and varnish this and that, and sail and rigging next weekend.

These aren't mine but this is what I am after:

http://static.flickr.com/217/498627727_e1a20b9838_d.jpg (http://www.flickr.com/photos/34043585@N00/498627727/)

The half dimension would be 3/4"x 3/4" tapering to about 2" max. I need to bend just the narrow pitchfork end, like the above. Is this accomplished by steam or by an angled cut in a block of wood? Would it be better to laminate? I have some ash, walnut, and locust laying around...the walnut comes in some crooked branch crotches and hardly even needs to be cut, much less steamed, for the right shape. But it has been down only one year...too green I think.

Bob Smalser
05-04-2012, 08:23 AM
Ash generally bends like a noodle when the core reaches around 190 degrees. Failures are usually because of insufficient heat as a result of leaky, uninsulated steam boxes combined with too little steam.

But on your gaff jaws, I wouldn't bother firing up the steam box at all. I'd use heat lamps and hot peanut oil. The cheesecloth wrap is merely to protect the varnish on this walnut gun stock. For your thickness, when the meat thermometer reaches 190-200 degrees and remains there for around 20 minutes, you should be able to tie those jaws in a knot if you want to.

http://pic20.picturetrail.com/VOL12/1104763/21637099/356506370.jpg

This particular job was for a physically-handicapped sportsman, and is a good example of what can be done without ruining the wood's finish:

http://pic20.picturetrail.com/VOL12/1104763/21637099/356506887.jpg

Further, unlike steambending, the hot oil method can be used to bend the same wood repeatedly if you don't get the bends right the first time or you experience too much springback.

wizbang 13
05-04-2012, 08:56 AM
Is that Dick Cheneys shotgun?

Dave Diefenderfer
05-04-2012, 08:58 AM
Bob, tell me more.... when you say hot peanut oil, are you talking like a turkey fryer? Put the stock in a plastic bag and into the big pot? Always curious how bending for stock fitting was done? I am trying to learn to be a better trap shooter, but struggle with proper firearm choices. I have several shotguns, but they are all specific hunting guns, and not ideal trap guns. My current efforts are to install a trap (raised cheek) stock, and a longer barrel on one of my shotguns. Will likely use the Morgan adjustable recoil pad for a better alignment, but that is about all I can swing out of by boat budget.

Dave

Skegemog
05-04-2012, 09:13 AM
I want to do something similar with gaff jaws in English Yew, any info on it's properties in terms of steaming etc.?



Ash generally bends like a noodle when the core reaches around 190 degrees. Failures are usually because of insufficient heat as a result of leaky, uninsulated steam boxes combined with too little steam.

But on your gaff jaws, I wouldn't bother firing up the steam box at all. I'd use heat lamps and hot peanut oil. The cheesecloth wrap is merely to protect the varnish on this walnut gun stock. For your thickness, when the meat thermometer reaches 190-200 degrees and remains there for around 20 minutes, you should be able to tie those jaws in a knot if you want to.

http://pic20.picturetrail.com/VOL12/1104763/21637099/356506370.jpg

This particular job was for a physically-handicapped sportsman, and is a good example of what can be done without ruining the wood's finish:

http://pic20.picturetrail.com/VOL12/1104763/21637099/356506887.jpg

Further, unlike steambending, the hot oil method can be used to bend the same wood repeatedly if you don't get the bends right the first time or you experience too much springback.

davebrown
05-04-2012, 09:14 AM
WB should publish a book just of Bob's posts alone. The conclusion I am making is it is the heat, primarily, that allows the bend with steaming, and, like the peanut oil suggestion, the steam keeps the wood from turning into a saltine cracker.

Bob Cleek
05-04-2012, 11:58 AM
WB should publish a book just of Bob's posts alone. The conclusion I am making is it is the heat, primarily, that allows the bend with steaming, and, like the peanut oil suggestion, the steam keeps the wood from turning into a saltine cracker.

It's been done! Bob has a couple of URLs in his tag line at the bottom of his posts. You'll find there quite a number of fascinating and beautifully illustrated articles Bob has written for WoodCentral and Fine Tools magazine. You could spend a weekend reading all of them and never get bored. Highly recommended.

The master at work:

http://www.wkfinetools.com/contrib/bSmalser/0_img/bobSmalser-220.jpg

Canoez
05-04-2012, 12:14 PM
This particular job was for a physically-handicapped sportsman, and is a good example of what can be done without ruining the wood's finish:

http://pic20.picturetrail.com/VOL12/1104763/21637099/356506887.jpg

Further, unlike steambending, the hot oil method can be used to bend the same wood repeatedly if you don't get the bends right the first time or you experience too much springback.

Nice work, as usual.

Don't you find that the lignin in the wood achieves a "set" after the first heating which makes it a bit more difficult to move a second time? Is the lower temperature in the hot oil method that you're using the secret here to being able to do this repeatedly?

Bob Smalser
05-04-2012, 02:00 PM
Don't you find that the lignin in the wood achieves a "set" after the first heating which makes it a bit more difficult to move a second time? Is the lower temperature in the hot oil method that you're using the secret here to being able to do this repeatedly?

Dunno. But I suspect that walnut bends repeatedly more because, compared to a boat frame, these gunstock wrists aren't being bent very far or very severely. Walnut is also well known as one of the easiest woods to bend. For example, it took several fitting and bending sessions to get the bends right on the doublegun I picture. And when guns are sold or pass from father to son, even hundred-year-old walnut already bent a couple times will bend again without incident. This technique originated in Great Britain, where it's been done this way for a couple hundred years. The only gotcha is evaluating whether highly-figured wood will bend without cracking. Mistakes can cost a $grand out of pocket real quick.

Heating is simple. Common peanut oil from Safeway is heated to near boiling in an old teakettle and dribbled over the cheesecloth. The cheesecloth is firmly tied with string to the wood so there are no air pockets to overheat and scorch the varnish. Under the heat lamps, the cheesecloth also serves to hold the hot oil in place for more-rapid heating. The entire job usually takes less than half an hour. The jig has a hole in the bottom and is cantilevered off the bench so excess oil can drip into a pan beneath.

The job was traditionally done using linseed oil. But I find linseed smokes and burns too easily and choose oils with higher flash points instead. Peanut is only one of the high-flash-point oils that can be used.

You don't hear about this method much because although it's an old technique, it was proprietary to various gunmakers and guilds and an attendant secret-voodoo cult was built up around it, not dissimilar to boatbuilding. Hence the smoking, flashing linseed oil to impress the customers. But it's really simple. Just use a thermometer, high-flash-point oil and lots of cheesecloth and you won't have any trouble doing it.

Would I try to bend Yew this way? Sure. It's the heat that bends wood, not the steam. All high-moisture content wood does is transmit that heat internally a bit quicker than dry wood. But these hundred-year-old sticks of walnut are as dry as you can get it, yet don't have any trouble bending once they reach the right temperature at the core.

http://pic20.picturetrail.com/VOL12/1104763/21637099/356506549.jpg

davebrown
05-04-2012, 06:49 PM
Amazing. I truly learn something everyday doing this. I initially started out with walnut gaff jaws, but then cut some more out of ash, thinking it would bend easier. Even better, the walnut is air dried and the ash is kilned. I'll try them both. I'd love to have the walnut work. It is figured and stunning. Because of the figure it might not bend as well. If you're still following, Bob, is it possible to do this basting in an oven? I mean the gaff jaws, not me. I wouldn't be in the oven.

Bob Smalser
05-04-2012, 07:11 PM
... is it possible to do this basting in an oven? I mean the gaff jaws, not me.

I guess so. But fumbling around in tight, indoor spaces with a pint or more of boiling oil next to either a pilot flame or a red-hot electrode isn't my cup of tea. Plus you have to be able to handle it while it's hot to get it into a vise for bending. And my vise and my oven are a half mile apart.