doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Stock Bending methods?

Hello Builder,

Yes, first foil then oil soaked rags. I have the description somewhere. I'll look it up and post it.

JC

Found it!

"I bend a thru-bolt gun just like any other gun but when I'm done, I take the stock off and gently bend the thru-bolt so that it lines up with the hole in the newly bent stock. I suspect that o/wise the bolt acts as a spring trying to move the stock back to where it was.
My jig is just like Mike's (it's based upon his old jig). However, I don't know what Mike's process is. Mine is that the oil never touches any wood or metal. I wrap the wrist in Saran Wrap for 3 or 4 wraps, then wrap the spot where I want the bend to occur with a shop rag and tie it down.
I then cover everything with alum. foil to prevent the lights from blistering the finish. Nothing is exposed except the shop rag. I turn on the lights and start eye-dropping the oil onto the rag, soaking it thoroughly.
My process usually takes about 30 min., once I turn on the lights. My lights are closer to the wrist than Mike's, though, if his are 11" away. I have a tape measure stapled to the back of the jig, and I tape a pencil or similar to the butt, so that I have a "cold" measurement starting point and I can see exactly how much I have bent the stock at any time. After cool down, I can compare pointer indications to see how much I moved the stock, and thereby know whether I need to heat it back up and bend again. I measure up from the floor of the jig to check for drop change.
The TRICK is to accomplish all this w/o messing up the finish, damaging the gun when you clamp it down, messing up the stock/action joint or changing the stock/trigger (sear) interface. I c-clamp the stock fork to the action (with leather buffers) before I put the gun in the jig. You might have to do a little carving to eliminate a stock/sear contact point afterwards, if you moved the fork at all. You might also have to bend a long trigger-guard tang to make it easy to get the stock on and off.
I'd do a lot of cheap guns to start out with, if I were you.
HTH!
Cush


JC

Reading this makes me think of a couple of things:

1. I was taught to leave the barrels on the gun and remove just the forend. Not sure why, just the way I was taught.

2. Heat lamps can torch a stock with hot oil on it quickly. Do not leave the gun unattended while being heated. Oil soaked rags around the stock will not protect the stock from burning. So, be careful and my experience has been to heat the stock slowly by keeping the lamps about 10"-11" away and not try and rush things. I have toasted or discolored (did not completely burn) one of my own stocks when learning.

3. I was taught to clamp just the action of the gun. I have since experimented by clamping both the action and the head of the stock with a leather covered wood vise and that seem to help lessen the separation between the metal and the stock. Where/what do you guys clamp?

4. I have always ensured the through bolt is tight, but I have not tried to open the hole or bend the bolt. Bending the bolt seems to me to be a problem. First, wouldn't a bent through bolt (even slightly) be difficult to screw in? And second, how would you make sure that the bolt is bent in the right direction? As you tighten the bolt, it could pull the stock in the opposite direction. Enlarging the through bolt hole seems to make more sense, but again could this have some negative effect?

Finally, because of the gap created in the metal to wood fit when bending O/Us, I have been hesitant to try this on my sidelocks. The last thing I want to do is screw up the metal to wood finish on that king of gun.

David,

I also bent a few stocks myself using a similar jig as above.
I also noted a tendency of the wood to pull off the metal on the side where it is supposed to stretch some. I read somewhere that wood bends in fact by compressing the fibers on the side you are bending it towards and there is no significant stretch on the oposite side. I use an oven cooking thermometer that I insert into the rag I wrap around the stock. They say one should reach 200F or higher before bending. It is at that temp that the links between wood fibers come apart allowing permanent modification of the wood. I allow slow heating at a rate of at least 1 hour per each inch of stock thickness. I tighten up the jig to achieve my goals keeping the new dimesnions for a few minutes and then release while the stock is still hot. If it returns past the goals, then I retighten past the initial dimensions until I achieve the goals. I can operate my jig in both cast and drop at the same time.
I apply a clamp with good padding over the stock head to keep that end of the wood together on the metal.
I use the whole gun in the jig as the barrels would give me better alignment on to the jig, but I clamp only the action.
There will be movement of wood around the metal, although minute most of the time.

Slivers, does that mean when the thermometer reaches 200 degrees, you leave it at that temp for an hour per inch before you start bending? Please excuse me but I am trying to learn. Thanks.

I heat up the stock allowing one hour for each inch of stock thickness where I want to bend. The slow heating avoids scorching of the wood. Once the temp reaches 200F I keep it there for another 15 minutes to make sure the heat has penetrated the entire stock thickness, then I start to bend. If the stock springs back easily it's either going to be reluctant to follow your wish or it's not heated completely.

Thanks, I plan on building a jig this winter and am trying to find as much info on this topic as I can.

I have some pictures of my jig, I'll post them when I get home. I would like to thank the contributors of this forum for helping out when I wanted to learn about this.
I have just learned more tips on this matter from above posts.

here are the pictures: