Making A Wood Knife Handle
The handle of your new Custom Knife will likely be the first thing people notice and touch. They might comment on the shape of the blade, how "shiny" it is, or how sharp. But the handle will capture them. They'll turn it in their hands a few times as if they're memorizing the grain and contours.
The first four pictures attached here show different pieces of Flame Box Elder, from a raw green log, to a kiln dried and stabilized wood block, then that same block sawn and book matched as knife "scales", and finally that block again as a finished knife handle. I chose Flame Box Elder for this because the bright red streaks help keep our eyes oriented to the block as it goes through the different processes. This has both nothing and everything to do with putting an attractive handle on a Custom Kitchen Knife. If the wood isn't properly dried, professionally stabilized, sawn in the correct orientation to the grain or color, book matched, glued, pinned, and finished, a beautiful piece of wood is ruined, and we get to start over.
I'm going to try below to describe what happens at Keith Nix Knives. I have no idea what other people do. So let's get started!
1- Why use stabilized wood? What is stabilized wood and how do you do it?-
Wood that is stabilized has undergone both vacuum and pressure to force a liquid resin completely through a block of wood, into every pore and crevice. It is then heated to a specific temperature and held there until the liquid "polymerizes", or becomes solid. At this point the wood is no longer porous, and becomes impervious to the shrinking and swelling associated with changes in humidity. It won't absorb the sometimes yucky stuff it comes in contact with when working in the kitchen or field dressing fish or game. There's a more in depth article on STABILIZED WOOD PRODUCTION right here at Keith Nix Knives. To follow up on it, CLICK HERE!
2- Sawing the block-
I usually send my wood to K&G as 2x2x12" blocks. When they come back, I can saw that block into four wood knife handle blocks of 1x2x5". At this point in time it is VERY important to look at your blocks, study the grain, and determine which of those 2" flats you want to be the faces of your handles. Nearly always the grain on one side will be curlier, burlier, more twisted, or have some attractive color variation that what you see on the adjacent sides. Make sure you saw your block so the pretty sides are OUT on your knife!
I like to start out with two knife scales or sides that are about .450", or just over 7/16 thick. I use a bandsaw so I can split a 1" block in half and have a little wood to spare for sanding, flattening, and such. Afterward, we will have two blocks that are .450" thick, 2" tall, and 5" long. Plenty of wood for the handle we're about to make!
3- Flattening the Scales-
After sawing and book matching the two scales of the handle, it is necessary to make each scale flat and parallel, so it will attach to the tang of the knife without gaps and voids. This also helps with drilling the pin holes perpendicular, straight, and to the proper size.
I use the 2x72 belt sander and a 9" disc sander for this operation, and check for flat and parallel on a granite surface plate and with digital calipers or micrometer. I can't stress enough the necessity that the side of the scales that will be glued to the tang be FLAT. If not, there will be gaps in your scale/tang joints.
I always use liners made from G10 or Micarta between the wood and tang of the knives I make. It is an aesthetic feature and serves no practical or structural purpose. Liners add a bit of color or contrast to the handle as a whole. To me, liners bring the whole handle together as a unit, and offer some color contrast to the wood and steel.
I use primarily G10 for liners, in the .045-.060" range. There are several colors in stock in the shop but I lean toward black or a deep cherry red for nearly all knives. The material only needs to be roughed up with 100 grit sandpaper for better glue adhesion and its ready to go.
I use a small benchtop drill press for drilling pin holes. I clamp one scale half, liner, and tang together and transfer drill the handle holes right through the tang holes in the blade. This ensures good line up, and saves the need for a mill and digital readout. I use 1/8 pins, so I drill with a #32 drill (.116), and follow that with a .1250 reamer. This makes for a snug hole for the pins.
6- Rough Sanding-
Once the pin holes are reamed, I dry fit the handle to the knife tang and belt sand a rough finish, making sure to get a good start on the contours of the handle, breaking all sharp corners down to gentle contours. After this, I disassemble the knife handle and put it back together without the knife, This step is to shape, sand, and finish the front of the scales where they actually meet the steel of the knife at the ricasso. Once glued it would be impossible to finish this part of the handle without scratching the already polished blade itself with sandpaper.
7- The Glue Up-
Once the holes are drilled and reamed, we're ready to glue the handle to the tang of the knife. I use West Systems "G-Flex" epoxy glue, because it retains some flexibility even after it sets and cures. I apply a thin coating to all mating surfaces, the scale, liner, pins, and tang. The pins are dipped in epoxy and worked back and forth through the pin holes to assure a good coating of epoxy inside the holes. It's important at this time to have already finish sanded the front of the handle scales. (See #6 above) Don't forget this step!
Once the handle is glued and assembled, I use two or three quick clamps to LIGHTLY squeeze the handle scales to the tang of the knife and secure them until cured. An important note here is to not clamp too tightly. Doing so creates the possibility of squeezing too much glue out of the joints, and causing a GLUE STARVED JOINT. Just don't do it.
After clamping, there will be glue seeping out of all your joints. gently rub all this away, especially from the FRONT of the handle where you've already finished the wood. At this point isopropyl alcohol is a good solvent for the wet epoxy. Be sure not to rub too much on the front as the alcohol can erode the epoxy from under the front of your scales, leaving an empty joint!
8- Finish Sanding-
G-Flex epoxy is a 24 hour cure glue, so give it time to do the work of setting and curing fully. After that its back to the belt sander for some final shaping and removal of "squeeze out", or the excess glue leaked out of the joints due to clamping. After this I use a half sheet hand held orbital flat pad power sander. I start with 120 grit and smooth the handle to its final shape. It's pretty quick work if you apply a little pressure! Be careful here to not create any deep gouges by oversanding in one spot.
After the 120 grit, I usually jump to 400, then 800, 1000, 1500, 2000, and finally 2500 grit for a final finish. Once to 2500, the professionally stabilized wood will take on a lustre and shine like it already has a coat of satin or semi-gloss finish on it. Because the wood is stabilized, there is no need for any other finish at this point. a coat of paste wax and a good buffing is all it needs!
9- The Finish-
If the customer does want a high gloss knife handle finish I apply two to three for a Tru-Oil finish, a blend of boiled linseed oil, varnishes, and hardeners that dries faster than pure linseed oil. Tru-Oil makes a very durable waterproof finish that is EXTREMELY glossy. A 4 ounce bottle will do dozens of knives if you apply it with a gloved finger, rubbing vigorously to make sure the oil is worked down into the pores.
This is a quick and dirty list of the steps required to attach a handle to the tang of your kitchen knife and then make the grain and wood color stand out in a beautiful and satisfying way! Or you can choose an "All Synthetic Handle".
More FREE Learning:
Learn About Stabilizing Wood HERE!
Thanks for reading,