Advice on my first G10 handle please!

[SkagSig40]

Hey guys,
I'm a new maker and have ground a few 1084 blades that have come out half decent and deserve a nice G10 handle. I watch a few great videos but still have some questions. I'll mostly be using my Northridge 2x72" grinder for handle work.

*I have a tile saw to cut the G10 to rough shape. I see on many videos some guys use a respirator with a P100 filter, some guys only wearing a simple dust mask and some wear nothing at all. Are there certain parts of the handling operation that you don't need to wear a mask of some kind? Do I just vacuum up the G10 dust for clean up?

*What type of belts and what grit do you guys use as you progress? If I use a belt I used on steel can I use it on G10 and vice versa or is that a bad idea?

*I plan on having G10 slabs attached with Acorn/Luke bolts or corby bolts and also have a nice G10 liner of a different color then the main G10 slab. Should I use the G-Flex epoxy to glue them together before attaching them to the tang? I plan on doing a little shaping to the G10 like on the front of the grips before attaching to the tang for final fitting.

*how much clamping pressure do I use when gluing the G10 together and to the tang steel? I have heard you don't what to much as you can press out the epoxy? What is the correct amount of clamping pressure?

*Lastly I'd like a good grip but also want a shine on the handle? What would be a good compromise between grippiness and a nice finished shine?

Thanks for any advice you may have for me and please feel free to add any other advice! Many thanks!

 

[kuraki]

G10 grinds so fast I don't spend any time sawing it to shape. I just saw a rectangle large enough for the scale, drill my mounting holes, pin the knife together and grind to shape with a 36 grit zirconium belt. To finish G10 I go right to a 120 grit. For a grippy surface I leave it at 220. For a smoother surface I go from the 220 belt to hand sanding 600 and 800 (wet). You can use a belt you used on steel. You can use any belt. It grinds very easy and doesn't burn like micarta or wood can.

I glue up my liner and G10 slab in rectangles and grind them to shape together. I glue them with CA glue.

When gluing to a tang with G-flex or T-88 I use small spring clamps only. I also grind or drill recesses in the liner through to the scale material to give epoxy some cavities to reside in and adhere directly to the scale. In this case using corby or acorn bolts, they are your clamps. Get your faces flat, get some epoxy in the threaded fastener to serve as loctite, screw them together until they're tight, but you don't need to go to town on tightening them. I don't have a torque value for you here. I'm really watching to see epoxy come from the entire seam so I know I have good coverage/contact and balancing that with not cranking it down so tight I have to readjust a good grip on the screwdriver and bear down on it. Just tight.

Shiny G10 is still rather grippy even wet. The only time it feels slippery to me is with dry cold hands. There isn't much compromise here. If you want it to shine you have to sand to 600-800 or further and buff.

Other advice: glue lines suck. They take what would have been a really nice looking laminate material and turn it into something that looks amateurish and poorly done. Get your tang flat. Get your liners flat. I use CA between the liner and scale because it's so thin, and when gluing them together I try to squeeze the glue out, on a hard flat surface. You won't squeeze all of your CA out, in my opinion. Let the scale and liner cure fully. Flatten it again. The key to avoiding glue lines is flat flat flat.

 

[SkagSig40]

Thank you very much for all the great information! When you say get your G 10 flat and your tang flat how do you accomplish this? I was assuming they are already extremely flat from the factory? Just eyeballing my knife tang and handle material they look pretty flat to me.
Also what is CA glue? thanks again!

 

[kuraki]

It's not. It's very close. Closer than a lot of other materials you're working with, but not really flat. I use a piece of glass that I cut into a 12x12 piece and I lay a sheet of sandpaper on it, then sand the side of the scale in a figure 8 motion. This is the best way of getting something dead flat without a surface grinder. Your tang needs to be flat too. You don't want to rely on clamping pressure to mate your scales and tang. It might work, but you'll also have a knife that's built in a constrained state, rather than one that is adhered in a relaxed state.

CA glue is the colloquial term used here for any type of cyanoacrylate glue (super glue). Whether is thick gel, medium thick gap filling, thin, CA glue. Lots of different brands out there. I use this brand, works well, available on Amazon:

The spray can is an accelerator. It makes adhesion instant. I don't necessarily recommend using that on laminating scales and liners, because sometimes the glue can cure too fast to get it clamped down. I have a knife sitting on my bench that I did this on, with beautiful clean liners on one side and ugly messy poorly fit liners on the other because of this. Now I just glue them, clamp them to my bench and do something else for an hour or so.

 

[Drew Riley]

Any respirator/dust mask is better than nothing, but I normally prefer a half mask or my resp-o-rator. Any particle filter should be adequate.

Kuraki pretty much nailed everything else. For liners, I'll spread a few dabs of CA glue just to stick them together for drilling and roughing in, trace my handle profile and cut close with my bandsaw. I then use some sort of 2-part epoxy to go on the tang, but this is more of a moisture barrier than anything, as I rely on mechanical fasteners to keep it in place (corbies, peened pins, etc..). I'll normally run the insides of my scales over a surface plate with some rough grit sand paper. This does two things: roughs the surface for glue up, and also helps to ensure flatness.

Spring clamps should provide more than enough pressure. Just double check for separation/glue lines, especially if you're pushing in a lanyard tube or something. The rivets should pull the rest together pretty nicely. I also like to drill "glue holes" in my tangs as it gives excess glue somewhere else to go, and helps to create a better bond (not that I rely on that to hold the scales in place).

As for shaping, I usually just use a 120 grit and finish with a 220 or similar. I may polish it with some 400 to 600 grit paper and or hit it on the buffer for a second or two, but it really just depends on the knife.

 

[kuraki]

I forgot about the respirator. I wear my full face whenever working with G10, micarta, wood, carbon fiber. The only time I don't when working G10 is when I'm hand sanding wet. And I keep it wet so there is no dust.

 

[noseoil]

Above is good advice. I typically do the liners when assembling the wood, G10 or micarta all at the same time. Holes are drilled to size, parts all laid out & cleaned with acetone & the epoxy (G-Flex) is mixed. Assembly starts with the blade being coated on one side (a thin coating), then the 1st liner, the finished scale & fastener is inserted from that side. The other side is glued the same & then the fasteners are tightened.

I coat each surface on every part that will be glued. Flat parts, cleaned fasteners & all surfaces to glue & coarse sand paper to give the epoxy a surface to key into. If you do this each & every time, it always works & makes a good bond. If you cheat & skip a step, there can be problems. Surface prep, flatness & cleaning will give a good bond on flat parts.

Lately I've been using pins or tubes & small "C" clamps to hold things in place, then putting the assembly in my heater (truck outside in the sun). This bumps the epoxy enough to set a bit faster & in Tucson it works in the winter, unless it's a cloudy day. Then it's just a box with a small shop light in a reflector set to warm things up. Epoxy can be slow in cooler temps, so it's nice to kick it off with some heat.

Clean up with the regular belts, but I use old belts for cleaning up epoxy, micarta & steel, new ones are for steel. I made a few sanding blocks from conveyor belt for flats & curves. They weren't thick enough, so some solvent based contact cement worked to get them the right thickness. Flat blocks for flats, curved ones for curves.

Above posts are very good for what you're going to do, but we want to see pictures when they're finished!

 

[Stacy E. Apelt - Bladesmith]

G-10 is fiberglass in a hard resin. When sanding/grinding G-10 you are making very finely powdered glass fibers. These will get on skin and make you itch. If inhaled, they are very bad for the lungs, In the eyes they can cause a bad itch and other problems. AVOID all these.

Have good dust extraction when cutting and sanding. Doing it wet is the best way. When done, vacuum everything within three feet very well, and wipe down with a damp cloth or tack rag to remove all the dust you can.
OUTSIDE, blow or dust off your clothes, and toss them in the washer as soon as you go in and change.
You need a good respirator with a P100 filter and preferably full faced. Wear it all the time you are in the shop working on G-10, not just when grinding or sawing. The fine particles will float in the air for a good while.