I have attached thin G10 and Carbon-fiber scales to stainless-handled Spyderco and Byrd knives with great results. Start by making a paper pattern and transfer it onto the thin scale material. Make the pattern slightly bigger than the scale so you can bevel it down to fit. Keep in mind that some of the newer stainless Spyderco knives have multiple clip screw mounting holes. Start with the older knives that take a scale on one side only until you get a feel for drilling the scales to match.
IMPORTANT! Remember that you need to take precautions with any of the synthetic materials, (and some hardwoods), because of their toxic/irritating nature. This means proper masks, goggles, ventilation, and dust control. Do not breath any of the dust. I also wear a snug-fitting nitrile/poly type gloves to protect my skin. I also use a hepa filter vacuum with the hose placed next to the work area when I use the Dremel because of the dust.
After cutting to shape with a small saw/scissors/Dremel, I test fit the piece. Then the stainless surface and scale should be cleaned with alcohol and set aside to dry. Some like to rough up the surface which is your choice. Using an quick-setting epoxy I apply a thin amount to the scale taking care to not go to the edge as it will squeeze out as you clamp it together. I use a credit card type piece of flat plastic to drag the epoxy evenly across the scale. When clamping make sure that you use a piece of wood under the clamp to apply pressure evenly across the surface. At this time make sure that you clean off excess epoxy making sure it does not get into the mechanism which would make your knife a fixed-blade. After it sets completely unclamp it and sand the edge of the scale down to the edge of the stainless at an angle matching the bevel that is already present. Finish to your desired texture and enjoy.
Final thoughts: Don't rush it. Make sure you take your time to ensure the best results. Also I would highly recommend starting on a less expensive knife like a Byrd to perfect your technique. Finally, please take care with the dust from the scale material. A nice knife scale is not worth lung, skin, or eye damage. Have fun.
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