Cliff Stamp
BANNED
- Joined
- Oct 5, 1998
- Messages
- 17,562
First was some small wood, and relatively clear, with no significant knots. A small piece of alder was used as a baton, about a pound, heavy elbow swings were used (~25 ft.lbs calibrated from lead weight drops) enough energy to damage most heavy folders quickly and light ones immediately. Three rounds were split with each knife :
http://i7.photobucket.com/albums/y269/CliffStamp/swamp rat/ratweiler/rat_rounds_r1_split.jpg
No effect on either blade. They were similar in terms of ability, no real difference noted. The baton was way too light for this size of knife, it was really inefficient, like washing a floor with a toothbrush. Twenty nine and thirty one impacts for the Heafner bowie and 31 for the Ratweiler through the sticks.
Four more rounds were chosen for each, either more dense wood, or a few small knots. The splits were still done with maximum efficiency, meaning use of breaks in the wood and avoiding chisel cutting knots. The baton was moved up to a sensible size, still alder but now three pounds. Impacts were from the shoulder (~50 ft.lbs) these tend to break folders pretty much instantly.
http://i7.photobucket.com/albums/y269/CliffStamp/swamp rat/ratweiler/rat_rounds_r2_split.jpg
The black stuff on the wood is the coating of the Ratweiler coming off. Again no real difference noted, 59 and 60 impacts for the Heafner and Ratweiler respectively. Heavy down force was used on the handles of both knives. Both had decent feedback, but nothing serious, no gloves were used and there were no problems controlling the knives during the splitting.
Finally three problematic pieces were noted, significant knots, one for each which was even cross knotted and large. The first two split similar to previous, just a few more hits required. The last two were different. Full force hits made about 1/4" progress through the problematic areas and after 1-2 hits I almost knocked my index knuckle out of joint, I had to wrap the handles of the blades :
http://i7.photobucket.com/albums/y269/CliffStamp/swamp rat/ratweiler/rat_rounds_r3_split.jpg
It took 47 and 57 impacts for the Heafner and Ratweiler respectively, with the majority of each being on the last round. The Heafner chipped in two places clearing through the knots, it was impossible to keep the blade stable, there was no way to put enough pressure on the handle. The chipping was minor, a small fraction of a mm, it was removed with about 100 passes on a coarse SiC stone.
This was mainily a quick check to see if the primary hollow grind on the Heafner would blow on a knot. The edge is 0.031" thick and ground at 18.0 (5) degrees per side, this is pretty close to optimal for a heavy wood working blade. The Ratweiler is 0.035" thick and ground at 22.2 (2) degrees per side. The Heafner has been used a lot, so the chipping may have been an accumulation issue, or it may have just been a bad twist.
The Ratweiler was reprofiled to 18 degrees per side and the above will be rechecked. The blades were also compared in chopping, the Heafner is significantly heavier (660 vs 540 g) and more forward balanced and it shows in the penetration and it was more fluid in some alder (cut both batons earlier). Both can be shifted to rear grips to increase power. The cutting ability seemed similar, with the Heafner having a slight advantage carving the handles, but both would chop the handles out faster than they could be carved.
-Cliff
http://i7.photobucket.com/albums/y269/CliffStamp/swamp rat/ratweiler/rat_rounds_r1_split.jpg
No effect on either blade. They were similar in terms of ability, no real difference noted. The baton was way too light for this size of knife, it was really inefficient, like washing a floor with a toothbrush. Twenty nine and thirty one impacts for the Heafner bowie and 31 for the Ratweiler through the sticks.
Four more rounds were chosen for each, either more dense wood, or a few small knots. The splits were still done with maximum efficiency, meaning use of breaks in the wood and avoiding chisel cutting knots. The baton was moved up to a sensible size, still alder but now three pounds. Impacts were from the shoulder (~50 ft.lbs) these tend to break folders pretty much instantly.
http://i7.photobucket.com/albums/y269/CliffStamp/swamp rat/ratweiler/rat_rounds_r2_split.jpg
The black stuff on the wood is the coating of the Ratweiler coming off. Again no real difference noted, 59 and 60 impacts for the Heafner and Ratweiler respectively. Heavy down force was used on the handles of both knives. Both had decent feedback, but nothing serious, no gloves were used and there were no problems controlling the knives during the splitting.
Finally three problematic pieces were noted, significant knots, one for each which was even cross knotted and large. The first two split similar to previous, just a few more hits required. The last two were different. Full force hits made about 1/4" progress through the problematic areas and after 1-2 hits I almost knocked my index knuckle out of joint, I had to wrap the handles of the blades :
http://i7.photobucket.com/albums/y269/CliffStamp/swamp rat/ratweiler/rat_rounds_r3_split.jpg
It took 47 and 57 impacts for the Heafner and Ratweiler respectively, with the majority of each being on the last round. The Heafner chipped in two places clearing through the knots, it was impossible to keep the blade stable, there was no way to put enough pressure on the handle. The chipping was minor, a small fraction of a mm, it was removed with about 100 passes on a coarse SiC stone.
This was mainily a quick check to see if the primary hollow grind on the Heafner would blow on a knot. The edge is 0.031" thick and ground at 18.0 (5) degrees per side, this is pretty close to optimal for a heavy wood working blade. The Ratweiler is 0.035" thick and ground at 22.2 (2) degrees per side. The Heafner has been used a lot, so the chipping may have been an accumulation issue, or it may have just been a bad twist.
The Ratweiler was reprofiled to 18 degrees per side and the above will be rechecked. The blades were also compared in chopping, the Heafner is significantly heavier (660 vs 540 g) and more forward balanced and it shows in the penetration and it was more fluid in some alder (cut both batons earlier). Both can be shifted to rear grips to increase power. The cutting ability seemed similar, with the Heafner having a slight advantage carving the handles, but both would chop the handles out faster than they could be carved.
-Cliff
