Knife handle scales fasten to tang only with epoxy (vid)

[BluntCut MetalWorks]

I was looking for ways to reduce weight on my little 4" mini-petty/paring. One of the way was to eliminate hardware from handle. So, I am sharing my own little test whether epoxy + hidden epoxy pins can strongly fasten scales to tang. cma: It's not scientific nor a how-to nor claims nor [ tbd ]

:foot: if this turn out to be my ignorance, which does more harms than goods, I will gladly edit/delete content/video as appropriate.

Test subject:


Thanks for watching & comments
[video=youtube_share;EBR9Sr4AjKw]http://youtu.be/EBR9Sr4AjKw[/video]

 

[Drew Riley]

I was very impressed with how well the epoxied scales held up to the abuse. I think my biggest concernes would be after the epoxy continued to cure and eventually become more brittle, whether it be simply from age, UV exposure, or heat. I'd be curious what effect moisture/humidity would have over the long term as well.

That said, west Systems definitetly makes one of the better two part epoxies. I don't think your test would have faired as well with something like Loctite or another low cost 5, 10, or 60 minute epoxy.

 

[BluntCut MetalWorks]

More curing time could gain additional strength at the cost of toughness, so I don't know whether this trade off (strength <> brittle) is good or bad. UV exposure will be minor because the scales are opaque. Rust/time probably most concern, since by then scales will be hold together solely by short hidden epoxy pins.

Indeed West Systems (G/flex & other) is professional grade epoxy and also known to be tough/flex after cured. I still have 5 minutes 2 parts Devcon and 15 minutes 2 parts mid-cure epoxy, I'll do the same test using them when time permits.

I was very impressed with how well the epoxied scales held up to the abuse. I think my biggest concernes would be after the epoxy continued to cure and eventually become more brittle, whether it be simply from age, UV exposure, or heat. I'd be curious what effect moisture/humidity would have over the long term as well.

That said, west Systems definitetly makes one of the better two part epoxies. I don't think your test would have faired as well with something like Loctite or another low cost 5, 10, or 60 minute epoxy.

 

[BluntCut MetalWorks]

Partial handle with only 5 hidden epoxy pins

Epoxy: Devcon 2 parts 5 minutes
Wood: Mopani (Janka hardness 2940lb/f)

2 minutes video
http://youtu.be/aq11M6eIrK4

Devcon is very hard & brittle when fully cured (in 1hr). For this handle to works well, I think it needs at least 4 more hidden epoxy pins(1/4" in size). These tests (& some future tests) provide useful info for me but seem to be random noise for others, thereby thanks & respectfully lurk!

 

[ndp_2010]

it would be interesting to see how it goes with the full blade in real world abuse (prying, chopping etc) where the blade may flex and cause the epoxy to come off under different stresses than blows from the side and top- having said this - for most situations where you are not abusing the crap out of the knife it looks like the scales would hold pretty well!. Thanks for the video!

 

[Willie71]

This is consistent with my experience with Epoxy. With a properly prepped surface, and a slow cure epoxy, it typically requires destruction of the material to break the bond. I think the other thing to consider is that failure is typically not caused by a massive shock or bend, but repeated small forces over time. It is a different type of stress. Attaching a knife to a vibrating mechanism and timing it until it fails is more of a simulation for real world conditions. (Not criticizing your test, just offering thoughts.) This test will help dispel some of the myths about epoxy.