My knife needs a handle

[Ridgeway Forge Studio]

I will be the first to admit that I am not a bladesmith. I am a blacksmith, but I wanted to make a vegetable knife for a travel kit.

now, having never made a knife, I come upon the question of finishing the handle. I have searched without luck to understand precisely how to cut handle scales from raw seasoned lumber, and once cut, how to pin and finish without epoxy.

i would like to do this all without “modern” adhesives, if possible. 
 

my thought is simply to take a length of seasoned locust, cut it into rectangles, then drill and use a small diameter copper rod/rivet to attach the scales together, then sand and shape and finish with mineral oil. 
is this a recipe for splitting/cracking?

 

here is the knife:

 

the tang is about 4 inches or so

[Latticino]

Nice job forging the profile of your travel kit knife.

Your general strategy should work fine, and is a fairly traditional method for handling a "patch knife".  A few things to consider:

1. Drill pin holes in the tang before heat treatment
2. Don't forget to anneal your rivet material.
3. Make tang as flat as possible to mate up cleanly with the wood scales (sand those flat on a surface plate or piece of tempered glass as well)
4. Consider use of a period adhesive if possible (i.e. rabbit skin or horse hide glue).  If you do a nice sequence is:  drill pin holes in tang (I like three 1/8" diameter, but you go with your preference), glue one side scale on and drill through the scale using the tang holes as a template, glue the other side on and drill holes through the second side from the holes already drilled in the first side
5. Take care riveting the pins in place to avoid too much stress on the wood from expansion.  If you go the period glue route, you might be able to shape the scales in place first, then rivet.  If you do that a nice enhancement that is very period is to add a washer (brass or copper) on each side of the rivet which can be hammered to a slight dome shape.

[Ridgeway Forge Studio]

Latticino, 

Thank you for this: this is the guide I needed. Most that I was finding were for 'bladesmiths' already familiar with the process of making handles. 

As far as wood goes, I have some well seasoned locust: I was planning on cutting it down to 1/2" thick or so for each of the scales, trying to use the best grain I can find. 

Is there anything I should do to the wood before I follow those steps? 

[JHCC]

As long as the wood is well-seasoned, you should be okay. I would only add two suggestions to Latticino's:

1. Another period-correct adhesive would be cutler's pitch, which is a mixture of pine resin and filler. This is applied hot to the two pieces, which are then put together and allowed to cool. Two old recipes are:
   1. One part resin to one part brick dust.
   2. Four parts resin to one part beeswax to one part brick dust.
2. Don't use mineral oil; it doesn't dry. Use linseed oil instead.

[Ridgeway Forge Studio]

JHCC - You made me think for a moment; I don't think I wrote the right thing. I assumed [incorrectly] that cutting board oil was mineral oil; I was planning to treat the wood like a cutting board, since this will be for food use. 

I suppose I will have to find me some resin or some hide glue! 

 

[JHCC]

Another option for food-safe wooden surfaces is walnut oil. Unlike most other edible oils, it does dry, and unlike most commercial finishes, it doesn't contain any metallic dryers or the like. It's not cheap, but it works.

[Buzzkill]

You probably already know this, but I wouldn't recommend ever putting a knife with that type of construction and handle material in a dishwasher.

As long as you don't use anything known to be toxic it shouldn't be a problem on the handle.  Once dried/stablilized there shouldn't be much of a chance of transferring anything dangerous to the food.

Another thing to keep in mind for your slabs for scales:  Straight perfect grain is boring.  I did this with some walnut on my property for one of my early knives.  It looks decent, but because there is no variation in the grain, or knots, or anything else eye-catching it's just kinda "blah."  If that's what you're after then don't let me dissuade you.  If you want something with a little character then maybe find a spot with a knot or small branch.  If it's honey locust you might even be able to find a spot with an ingrown thorn.

[Ridgeway Forge Studio]

Buzzkill - I despise dishwashers all around. They make the dishes taste funny. [I don't know, I may just be weird. But I claim they leave a soap residue.]

Is there any problem, after impregnating the scales with cutting board oil [or walnut] sticking it in my toaster oven on low heat, lower than the temper, for a while to cure? I am torn - I can envision it either drying and splitting the scales, or curing the oil inside of the wood. 

Perhaps I will try with a wood test coupon before committing to the process. 

[JHCC]

We need to distinguish between finishing and stabilizing the wood. Stabilizing is when you completely fill all of the pores of the wood with a rigid material, often using a vacuum chamber to get the stuff all the way in. (For example, "Cactus Juice" is a popular brand of polyester resin that is cured in an oven; there are also low-viscosity epoxies that cure by chemical reaction.) Finishing, on the other hand, is applied only to the surface, and while it does inhibit changes in the moisture content of the wood, it doesn't stop it entirely. Some finishes do penetrate some way into the piece, but they don't fill up the pores all the way through. Thus, a stabilized piece will be dimensionally stable and unaffected by moisture, while a finished piece can still expand and contract with changes in atmospheric humidity or through getting wet while washing.

Also, oil finishes cure by oxidation, not by heat. Soaking a piece of wood in oil and baking it might speed up the oxidation slightly, but only on the surface.

In short, unless you are willing to invest in a vacuum rig and the appropriate resins, your best bet is to make sure the scales are thoroughly seasoned and properly finished, and then take good care to keep the knife clean and dry when not in use. Either that, or invest in some pre-stabilized knife scales from a knifemaker's supply house or use a more stable material such as bone.

[Buzzkill]

What he said. 

I do have a vacuum system and use the aforementioned Cactus Juice to stabilize some of my knife scales.   I've also used stains to get the color I want and then followed up with Tru Oil or something similar and have been pleased with the results.  Stuff that is made for the beautification of wood gun stocks tends to also make wood knife scales really pop.  Just follow the recommendations for the product as if you were treating a gun stock and it should turn out well.

But yes, using a test coupon for just about anything you haven't tried before is a good idea.

[Latticino]

I have grown to like using Danish oil for a finish on my wooden knife handles.  I used to use tung oil, but it takes forever to dry.  The Danish oil is quick and gives a nice finish.  A top coat of furniture wax, polished out gives a very useful finish that can be easily restored.

[Ridgeway Forge Studio]

Latticino - Tung oil is what I was thinking of all this time! Not mineral oil... 

My brother is a woodworker, so I borrow some of his techniques from time to time. 

JHCC, You're right - I often use my toaster oven to help cure the oil faster, and I should add that I think I am confusing curing with polymerizing. I stick my oiled metal in the oven to polymerize the oil, not to cure it. it works well, and I can attain a straw temper under the linseed oil if I do it right, making a nice durable gilding effect. 

I'm curious about the effect of polymerizing oil-soaked wood. Most wood's flash point is 475 F [or thereabouts], so as long as I set it to 350, I shouldn't get charring, per se, but perhaps a nice Maillard Reaction from any sugars still in the wood. 

I still have to make some adjustments to the knife and anneal it today, so I suppose I will perform some of these tests while I do that. Its like science but with more fire...