03-06-2017, 12:13 PM
(This post was last modified: 03-06-2017, 12:25 PM by Paul-in-Plymouth.
Edit Reason: misspelling
)
A week ago I described making a pair of wooden wedges from fresh-cut red oak with my scrub plane ("Scrubbed Gluts"). My conclusion was that despite the putziness - the “Wedge by a Thousand Cuts” thing - the scrub plane was a surprisingly quick and fun way to do this. So much fun that I made another pair this week.
![[Image: IMG_2664%201_zpsljb8hzb3.jpg]](http://i1379.photobucket.com/albums/ah146/paul-in-plymouth/oak%20wedge2/IMG_2664%201_zpsljb8hzb3.jpg)
The situation is that I am not able to make them with the axe or draw knife because my dominant hand is somewhat impaired. I also don’t have a ripsaw I’m willing to use on green wood, and I didn’t feel like making a sled, etc. to do it safely on the bandsaw. That left the scrub plane.
I said I would make more wedges and experiment a little. I had coated the entire surface of the first pair with Highland’s End-Grain Sealer to prevent checking by slowing moisture loss. I wondered if I could allow faster moisture loss without damage by using only a partial coating on the tapers.
So, for the second pair I coated only selected areas I thought would be high-stress, basically all the cut edges, especially the apex. I left most of the tapers and the big ends uncoated. All the wedges then sat in my shop at 65F and ~32% RH.
Results were swift and dramatic. Within two days both of the partially coated wedges began to split. The splits initiated at existing flaws in the pith near the centerlines, but in the uncoated region adjacent to the coated apex, just where you might expect stress to become tensile.
![[Image: IMG_2669%201_zpsacxbuwrw.jpg]](http://i1379.photobucket.com/albums/ah146/paul-in-plymouth/oak%20wedge2/IMG_2669%201_zpsacxbuwrw.jpg)
Weight loss for the fully coated pair was a constant 1% per day for the week. For the partially coated wedges, the loss averaged 3% per day for two days until I terminated the experiment and coated them like the others. They should still be useful if they don’t crack more, just half as wide and twice as many. All the wedges still max out on the Timber Check meter at >25% moisture content.
One conclusion I draw is that the Highland’s End-Grain Sealer does work to slow moisture loss. Another is that I see more headache than opportunity in partially coating the tapers.
This week’s log was significantly larger and more irregular than the first. It looked like one branch of a fudge had broken off and the scar grew over to complicate the grain in this piece. (The other one was so simple.) My work-holding had to evolve to accommodate the extra effort needed.
![[Image: IMG_2633_zpsncxzuz89.jpg]](http://i1379.photobucket.com/albums/ah146/paul-in-plymouth/oak%20wedge2/IMG_2633_zpsncxzuz89.jpg)
I dug out some heavy-duty 8” C-clamps to help immobilize the log while I planed. The winner had 4” extensions welded into the top and bottom of the “C” for a reach of almost 8”. This 7-pound clamp sometimes served as anchor by itself, or it could be clamped to the benchtop using one of the 4-pounders.
![[Image: IMG_2642_zpsvufgqafl.jpg]](http://i1379.photobucket.com/albums/ah146/paul-in-plymouth/oak%20wedge2/IMG_2642_zpsvufgqafl.jpg)
gMike’s suggestion to saw partial cross-cuts was helpful. This shortened the chips and reduced resistance, important especially when squaring a bigger log like this and getting it down to size and also once the tapers got long.
I have the wedges I need now. If I find by some suitable wood that’s less splitty than red oak, I may make some more. Otherwise, we’ll see how these work.
![[Image: IMG_2664%201_zpsljb8hzb3.jpg]](http://s1379.photobucket.com/user/paul-in-plymouth/media/oak%20wedge2/IMG_2664%201_zpsljb8hzb3.jpg.html)
The situation is that I am not able to make them with the axe or draw knife because my dominant hand is somewhat impaired. I also don’t have a ripsaw I’m willing to use on green wood, and I didn’t feel like making a sled, etc. to do it safely on the bandsaw. That left the scrub plane.
I said I would make more wedges and experiment a little. I had coated the entire surface of the first pair with Highland’s End-Grain Sealer to prevent checking by slowing moisture loss. I wondered if I could allow faster moisture loss without damage by using only a partial coating on the tapers.
So, for the second pair I coated only selected areas I thought would be high-stress, basically all the cut edges, especially the apex. I left most of the tapers and the big ends uncoated. All the wedges then sat in my shop at 65F and ~32% RH.
Results were swift and dramatic. Within two days both of the partially coated wedges began to split. The splits initiated at existing flaws in the pith near the centerlines, but in the uncoated region adjacent to the coated apex, just where you might expect stress to become tensile.
![[Image: IMG_2669%201_zpsacxbuwrw.jpg]](http://s1379.photobucket.com/user/paul-in-plymouth/media/oak%20wedge2/IMG_2669%201_zpsacxbuwrw.jpg.html)
Weight loss for the fully coated pair was a constant 1% per day for the week. For the partially coated wedges, the loss averaged 3% per day for two days until I terminated the experiment and coated them like the others. They should still be useful if they don’t crack more, just half as wide and twice as many. All the wedges still max out on the Timber Check meter at >25% moisture content.
One conclusion I draw is that the Highland’s End-Grain Sealer does work to slow moisture loss. Another is that I see more headache than opportunity in partially coating the tapers.
This week’s log was significantly larger and more irregular than the first. It looked like one branch of a fudge had broken off and the scar grew over to complicate the grain in this piece. (The other one was so simple.) My work-holding had to evolve to accommodate the extra effort needed.
![[Image: IMG_2633_zpsncxzuz89.jpg]](http://s1379.photobucket.com/user/paul-in-plymouth/media/oak%20wedge2/IMG_2633_zpsncxzuz89.jpg.html)
I dug out some heavy-duty 8” C-clamps to help immobilize the log while I planed. The winner had 4” extensions welded into the top and bottom of the “C” for a reach of almost 8”. This 7-pound clamp sometimes served as anchor by itself, or it could be clamped to the benchtop using one of the 4-pounders.
![[Image: IMG_2642_zpsvufgqafl.jpg]](http://s1379.photobucket.com/user/paul-in-plymouth/media/oak%20wedge2/IMG_2642_zpsvufgqafl.jpg.html)
gMike’s suggestion to saw partial cross-cuts was helpful. This shortened the chips and reduced resistance, important especially when squaring a bigger log like this and getting it down to size and also once the tapers got long.
I have the wedges I need now. If I find by some suitable wood that’s less splitty than red oak, I may make some more. Otherwise, we’ll see how these work.