Kitchen knife frame handle questions

[Hubert S.]

I just completed my first knife with a frame handle. This was a small petty knife made from 0.06" thick AEB-L and I used a black G10 spacer between paper micarta for the handle. This turned out pretty nice and was pretty quick to do, so I want to make more. I have a few questions that I hope some of you can help me with.

The first questions is about the tolerance I should aim for between the spacer and the knife tang. For the petty knife, I happened to have a G10 liner that was a couple of thou thicker than the tang. I have two other knives I would like to use this technique on where I don't have anything close in size, and no combination of liners I have will get me there. I looked online and the closest I saw is around 10-15 thou oversize. I know epoxy will fill this gap, but I am a bit concerned about the racing stripe down the handle not being aligned with the blade. What tolerance do you think is acceptable? I can't think of a good way to reduce the thickness of a G10 liner uniformly with the tools I have. Is there a good method for this?

My second question is about the minimum height of the frame above and below the tang. I have right around 3mm on the knife I made. Does that sound reasonable? Can I go even lower? I trimmed a bit of the handle I made off the end as I had left it too long and ended up with a 3mm cut-off that I put in the vice and broke with a hammer. It took a lot more force than expected and while it failed at the glue line, about half the fracture surface had micarta on it, the other half looked shiny. I used West Systems 105 epoxy for the glue up and it appears that the glue joint is about as strong as the material.

My third question is about the best way to get a small pin in the handle like shown in the little sketch. Do you drill the hole in the tang first and try to drill the hole through the handle in the right place, or do you drill the hole in the handle first and then transfer that to the blade and drill it with a carbide bit? Or do you assemble only half of the frame handle and use the hole in the tang as a template for drilling? Also, how much metal do I need to leave above and below the hole in order not to weaken the tang excessively? Would a 3/16" hole be ok in a 3/8" tang?

As always, any help is greatly appreciated.

 

[FredyCro]

I did it just once and also used micarta as a spacer. I cut a slice off the block, one side was flat, the other one I finished as uniformly as possible first on the disk grinder and then by hand, it went quickly and I managed to get a good fit, I stopped maybe twice to measure the thickness with calipers. Once I had it down to 0.1 mm difference all around I stopped.

As for drilling, my first knife was a split block of wood, frame style but no middle piece. I used the knife as template to drill through one piece, put it all together and then drilled through whole block. I don't think you need to worry much about tang strength if you put the pin like in your pics.

 

[Cushing H.]

following (I might like to try this some day soon )

 

[imill3567]

For kitchen knives I don't use pins but I've been doing all my hidden tangs frame style for awhile now. I would say that 10thou is maybe as far as you want to go with size difference before the gap will be pretty visible up front, not sure about the misalignment. Drilling pin holes I first glue the handle up trying not to use a ton of extra epoxy and do a "bedding". Now you have a glued handle separate from the knife, I square up the front and get the knife fit in snugly. I then drill the handle for the pin hole with the tang location layed out. Put the knife in the handle held in with a clamp and go into the hole with a carbide bit if it's SS for carbon I torch anneal the tang so it can be drilled. Now you have a pin and you can get most of the shaping done without the knife in the way then glue everything up and flush up the pin and finish sand after final glue up.

 

[Stacy E. Apelt - Bladesmith]

If you use a good resin and a pin, some slop is acceptable, The resin will fill all the void. As the previous post noted, unless you use a tight bolster piece, make the front a snug fit.

 

[Hubert S.]

I did it just once and also used micarta as a spacer. I cut a slice off the block, one side was flat, the other one I finished as uniformly as possible first on the disk grinder and then by hand, it went quickly and I managed to get a good fit, I stopped maybe twice to measure the thickness with calipers. Once I had it down to 0.1 mm difference all around I stopped.

As for drilling, my first knife was a split block of wood, frame style but no middle piece. I used the knife as template to drill through one piece, put it all together and then drilled through whole block. I don't think you need to worry much about tang strength if you put the pin like in your pics.

Thank you, Fredy. I have been thinking about cutting spacers to size on the table saw. The micarta cuts pretty nicely, even though it smells quite bad. The scales I cut only needed a bit of roughing up to be ready for glue up.

I might try a handle without a spacer and mill slots for the tang in each half. That would make it easy to drill the hole for the pin in one side like you describe. Another option I thought about was gluing up a scale with a 0.06" spacer before milling the slots. The blade would be a bit thicker than the spacer, but as long as it is symmetric it would probably not look too bad.

 

[Hubert S.]

For kitchen knives I don't use pins but I've been doing all my hidden tangs frame style for awhile now. I would say that 10thou is maybe as far as you want to go with size difference before the gap will be pretty visible up front, not sure about the misalignment. Drilling pin holes I first glue the handle up trying not to use a ton of extra epoxy and do a "bedding". Now you have a glued handle separate from the knife, I square up the front and get the knife fit in snugly. I then drill the handle for the pin hole with the tang location layed out. Put the knife in the handle held in with a clamp and go into the hole with a carbide bit if it's SS for carbon I torch anneal the tang so it can be drilled. Now you have a pin and you can get most of the shaping done without the knife in the way then glue everything up and flush up the pin and finish sand after final glue up.

Thank you. I have to get some small carbide bits, or at least figure out a way to mark the hole location on the tang, and then drill it with a slightly larger bit after pulling the blade out.

 

[Hubert S.]

If you use a good resin and a pin, some slop is acceptable, The resin will fill all the void. As the previous post noted, unless you use a tight bolster piece, make the front a snug fit.

Thank you, Stacy. Maybe I should stick to the 0.06" blades with this method for now as I have a liner that gives me a tight fit.

I am wondering if a surface grinding attachment could be used to grind G10 liners down in thickness evenly, maybe with some double sided tape or a couple drops of superglue. I have been thinking about getting one of those for a while.

 

[Hubert S.]

following (I might like to try this some day soon )

The other day I mentioned to a colleague that I am a member here. So today, he told me that he looked me up and found some posts by me about using handle shaping templates and then said that there was some other guy who posted the most amazing wa handle pictures in the same thread. He could not remember the name, so I asked: "Cushing?". He said, "Yes, that's him". Those handles looked really good.

 

[Nick-D]

I finished one recently, I went with a spacer that was just slightly undersized. Then just tapered the tang roughly until I got a nice fit. Was easy enough and only took a few minutes.

 

[FredyCro]

I really like this method because it is much easier to have a really tight fit and have everything square from the very start. You also don't need a step down on the tang. Next time I will pop couple of 2mm hidden pins (stainless bycicle spokes cut to size) in the frame although I don't think they are necessary with quality epoxy. I wills use the middle piece as the guide for the holes.

Thank you, Fredy. I have been thinking about cutting spacers to size on the table saw. The micarta cuts pretty nicely, even though it smells quite bad. The scales I cut only needed a bit of roughing up to be ready for glue up.

I might try a handle without a spacer and mill slots for the tang in each half. That would make it easy to drill the hole for the pin in one side like you describe. Another option I thought about was gluing up a scale with a 0.06" spacer before milling the slots. The blade would be a bit thicker than the spacer, but as long as it is symmetric it would probably not look too bad.

One cool tip I got from YT, if you bandsaw the block, do not flatten it, the cut in the middle should align perfectly on the glue up and not show a glue line when finished.

 

[Cushing H.]

The other day I mentioned to a colleague that I am a member here. So today, he told me that he looked me up and found some posts by me about using handle shaping templates and then said that there was some other guy who posted the most amazing wa handle pictures in the same thread. He could not remember the name, so I asked: "Cushing?". He said, "Yes, that's him". Those handles looked really good.

Lol. Thank you.

 

[Hubert S.]

I really like this method because it is much easier to have a really tight fit and have everything square from the very start. You also don't need a step down on the tang. Next time I will pop couple of 2mm hidden pins (stainless bycicle spokes cut to size) in the frame although I don't think they are necessary with quality epoxy. I wills use the middle piece as the guide for the holes.



One cool tip I got from YT, if you bandsaw the block, do not flatten it, the cut in the middle should align perfectly on the glue up and not show a glue line when finished.

The one I made was a good bit quicker than the hidden dowel method. Unlike other shortcuts I've tried, I really like the way it looks and will be making more.

Not sure about that bandsaw trick, I'll probably stick with the table saw and a bit of hand sanding on the surface plate.

 

[Hubert S.]

Ok, I was thinking about Stacy's post some more and he mentioned a bolster and it took a while for me to understand that you can combine the two. I have some nice scale scraps that are a bit too short for a full handle, but long enough with a bolster. So, I'd like to try something like shown in the sketch. I am wondering if this will be strong enough since there is no wooden dowel to hold the two parts together, just the tang. Do I need a pin and/or shoulders on the tang?

 

[HSC ///]

Ok, I was thinking about Stacy's post some more and he mentioned a bolster and it took a while for me to understand that you can combine the two. I have some nice scale scraps that are a bit too short for a full handle, but long enough with a bolster. So, I'd like to try something like shown in the sketch. I am wondering if this will be strong enough since there is no wooden dowel to hold the two parts together, just the tang. Do I need a pin and/or shoulders on the tang?

It’s strong enough. Glue up a scrap of 2 wood blocks and try to break it apart. U will find it’s plenty strong enough. I make this style all the time

 

[Hubert S.]

It’s strong enough. Glue up a scrap of 2 wood blocks and try to break it apart. U will find it’s plenty strong enough. I make this style all the time

It was one of your posts in another thread that inspired me to try this. I chickened out, though, and used epoxy instead of superglue.

My concern is the end grain joint between bolster and main (frame) handle. Is that the test you are suggesting, end grain to end grain? In my case, it would be ebony end grain glued to micarta. I can't imagine that joint being particularly strong without reinforcement, so in my mind at least, the tang and epoxy would be what's holding the handle together.

 

[A.McPherson]

Good epoxy is ridiculously strong, as long as everything is clean when you glue it up.

If you're really concerned, use some small pins between the bolster and handle.

 

[HSC ///]

It was one of your posts in another thread that inspired me to try this. I chickened out, though, and used epoxy instead of superglue.

My concern is the end grain joint between bolster and main (frame) handle. Is that the test you are suggesting, end grain to end grain? In my case, it would be ebony end grain glued to micarta. I can't imagine that joint being particularly strong without reinforcement, so in my mind at least, the tang and epoxy would be what's holding the handle together.

You are overthinking this.
any test...
Try several samples and prove to yourself

the glue bond is stronger than the wood

 

[Hubert S.]

Ok, so I made a frame handle with bolster and no dowel. It turned out really nice, but I had milled the slot a tiny bit too narrow and cracked the bolster... Anyway, I ground the handle to have something to test the joint strength. Just a few taps on the work bench and the bolster came right off at the glue joint. The end grain joint is definitely weaker than the material (paper micarta/ebony). I used West Systems 105 resin with the 205 hardener, the surfaces were roughed up with 60 grit, everything cleaned meticulously. I coated both surfaces with plain epoxy to let the wood and micarta wick up as much as they wanted, and then used epoxy thickened with colloidal silica for the glue up. The epoxy was cured for three days. Without a tenon, this joint is definitely not strong enough. If anything in my procedure is wrong, I'd really like to know.

Below is a picture of what I did. You can see the crack in the micarta. This picture was taken after I had knocked the bolster off, I just put the two pieced back on the tang. That's why there is a small gap.

I am no longer sure whether I was overthinking this or not. Maybe the tang and a lot of epoxy would have reinforced this joint sufficiently. I don't really know what I've learned from this experiment, other than to mill the slot for the tang wide enough so it is not a press fit.

 

[HSC ///]

Ok, so I made a frame handle with bolster and no dowel. It turned out really nice, but I had milled the slot a tiny bit too narrow and cracked the bolster... Anyway, I ground the handle to have something to test the joint strength. Just a few taps on the work bench and the bolster came right off at the glue joint. The end grain joint is definitely weaker than the material (paper micarta/ebony). I used West Systems 105 resin with the 205 hardener, the surfaces were roughed up with 60 grit, everything cleaned meticulously. I coated both surfaces with plain epoxy to let the wood and micarta wick up as much as they wanted, and then used epoxy thickened with colloidal silica for the glue up. The epoxy was cured for three days. Without a tenon, this joint is definitely not strong enough. If anything in my procedure is wrong, I'd really like to know.

Below is a picture of what I did. You can see the crack in the micarta. This picture was taken after I had knocked the bolster off, I just put the two pieced back on the tang. That's why there is a small gap.

I am no longer sure whether I was overthinking this or not. Maybe the tang and a lot of epoxy would have reinforced this joint sufficiently. I don't really know what I've learned from this experiment, other than to mill the slot for the tang wide enough so it is not a press fit.

Try 2p-10 fast glue