Stock bent!

[Jerry V Lape]

 Finally tackled my problem curly sugar maple stock.  It had twisted as it finished drying out here in the Arizona desert after migrating from Pennsylvania.  First photo shows the setup with two heat guns, a hot plate with oil heating pan, and the bracing copied pretty much from several others which I had seen on various websites.  The 2d photo shows the toe of the stock with about 1/2" of cast ON.  The third show the stock as clamped after heating with the toe a little over 1/4" of cast off.  Released from the bracing the toe currently has 1/8" approx of cast  OFF.  Still have to final shape the butt.  However won't be too long now until it will be all assembled.  The hot oil did attach itself to the bare wood.  I am  hopeful the final shaping will remove enough of the surface oil to allow the Ferric Nitrate to stain the stock well.  Planning to TSP wash it next if the stock stays put.  I did leave it in the bracing for 24 hours after having maintained the wrist at 300 degrees for an hours before the wood felt willing to move.             

[PPatch]

Jerry; Nice setup and clear pictures, thank you.

Question: Why oil instead of water?

dave

[sweed]

+1 PPatch. Steam or hot water and tow sacks bent many things when I was building wagon/buggy wheels.  ?

[Jerry V Lape]

I did not think I could get water/steam hot enough to bend the sugar maple. I had tried steam on a hickory ramrod blank earlier without success.  (Probably didn't heat it long enough but lost confidence in steam none the less)   Plus,  prior experience having walnut shotgun stocks bent had been done by professionals using hot oil, and in these cases there was not any damage to even the finish on them.   I was able to maintain 300 degrees on the wrist with the oil and heat guns.  Steam doesn't get to higher than 212 degrees unless it is in a pressurized container.  I can tell you that even at 270 degrees this maple was not bendable.  It was only after an hour at 300 degrees that I finally felt some yield in the maple.  I heated the oil to 350 degrees in the pan and applied heat guns to the cotton cloth wrappings of the wrist to keep the oil hot.  As the cloths dried more hot oil was spooned on .  The excess was caught in a shallow pan and recycled to the heating pan.   I have observed the oil bending of walnut but this was my first effort at bending any wood and sugar maple is at the hardest to do end of the wood bending  spectrum.  So I choose the successful system I had observed. 

[PPatch]

Just wondering Jerry, thank you for the explanation. I would be afraid I couldn't remove that oil and thereby mess up any finish I attempted. It worked, so now you've a gun to finish, all good.

dp

[Dphariss]

Walnut can be bent with heat lamps and a jig to move it into place. Don't know about maple.

Dan

[Jerry V Lape]

Dphariss, 

I would have used heat lamps except the cost of setting them up was pretty high for a one time use.   Further, I already had a heat source with the heat guns.  And now you know that sugar maple can be bent but it isn't near as compliant as walnut. Some English gunsmiths have a permanent setup which pumps heated oil over the wrist until the wood is warm enough.  There is a You tube video of this method and there is a Midway USA video of Jack Brooks bending walnut stock with oil heated over his torch and moved by hand.  But there are none showing steam bent stocks.  I wasn't sure I could bend the maple at all but needed to try as the piece of wood was pretty expensive and I had already put a lot of work into the gun. 

[Scott Bumpus]

What kind of oil was used?

[Jerry V Lape]

Canola