Help removing handles !!without!! damaging them

[aporigine]

I have some wa-handled knives on which I wish to remove them. I have some tools but not a full shop by any means. I am asking for the sovereign procedure for taking these off without, say, getting compression damage on a horn ferrule or getting marks on the blade. How do all y’all shift the real stubborn ones?

 

[aporigine]

Cognate question.
How hot can i get a knife (oven) before beginning to affect the steel, even minutely?

 

[Just a DK]

Boiling water usually works for me. I use a thermos to keep the water hot as long as possible.

 

[sansho]

what kind of adhesive?
also, i'd guess the real question is what temp can you get the handle to before damage, not the steel. handle is probably more sensitive.

 

[HumbleHomeCook]

You can run up to around 180F or so with no issues. Put the knife on a cookie sheet or something and give it around 10mins. I like to wrap the blade in thin cardboard then lay a 1x4 or 2x4 along the blade and butted against the handle. Whack the wood with a hammer. If it doesn't go, I'll turn the oven up to 200, give it another five or so minutes and try again. Often you'll see some movement at this point so you know you're on the right track.

If it still doesn't budge, you need to start getting more creative and also wondering if it is epoxied.

 

[aporigine]

what kind of adhesive

something that scoffs at hot water
(edit) boiling

 

[aporigine]

You can run up to around 180F or so with no issues. Put the knife on a cookie sheet or something and give it around 10mins. I like to wrap the blade in thin cardboard then lay a 1x4 or 2x4 along the blade and butted against the handle. Whack the wood with a hammer. If it doesn't go, I'll turn the oven up to 200, give it another five or so minutes and try again. Often you'll see some movement at this point so you know you're on the right track.

If it still doesn't budge, you need to start getting more creative and also wondering if it is epoxied.

I am assuming it is epoxied.

However wa handles are designed to be replaced.

I know solvents that’ll give epoxy short shrift, but I worry they’d do bad things to the handle.

How do the pros do this? They must get “rehandle; return original handle” and **** the adhesive … all the time. If there’s a (not stupid expensive) tool, I’ll invest.

I am very willing to get creative within the stated limits. Handle and blade are to be separate and intact. No cutting tools.

 

[HumbleHomeCook]

I am assuming it is epoxied.

However wa handles are designed to be replaced.

I know solvents that’ll give epoxy short shrift, but I worry they’d do bad things to the handle.

How do the pros do this? They must get “rehandle; return original handle” and **** the adhesive … all the time. If there’s a (not stupid expensive) tool, I’ll invest.

I am very willing to get creative within the stated limits. Handle and blade are to be separate and intact. No cutting tools.

Just being a wa handle doesn't mean it is able to be removed. Most are but some aren't. If it's epoxied, that handle is a loss.

 

[SwampDonkey]

Usually I use a heat gun on low, it heats the tang enough to transfer down to soften adhesive and then do the Knives&Stones knocky block method. One lovely handle was like super glued on and had to be cut off. Sometimes it just be like that I guess. Getting mad at it definitely helps.

 

[aporigine]

Just being a wa handle doesn't mean it is able to be removed. Most are but some aren't. If it's epoxied, that handle is a loss.

Oh I so don’t want to be told this.
Guess it’s time for seriously unsafe chemicals.

Usually I use a heat gun on low, it heats the tang enough to transfer down to soften adhesive and then do the Knives&Stones knocky block method. One lovely handle was like super glued on and had to be cut off. Sometimes it just be like that I guess. Getting mad at it definitely helps.

I got <1 cm of tang. Dunno how to roast the tang and not get the blade too hot.

 

[SwampDonkey]

I got <1 cm of tang. Dunno how to roast the tang and not get the blade too hot.

carefully

 

[aporigine]

So the consensus is +creek , -paddle?

 

[Absolute Buffoon]

So the consensus is +creek , -paddle?

Most likely +creek, -paddle, +++++++++*****.

 

[Mr.Wizard]

Could cryogenic freezing help by making the resin brittle?

 

[ethompson]

An hour in a 190 sous vide and a surprising amount of brute force has always worked for me. Except for the one time someone used the strongest epoxy known to man and then it was just destruction

 

[Just a DK]

If epoxy i consider a loss. Other methods on epoxy risks knife.

 

[Just a DK]

also if spacers are used i consider a loss.

 

[aporigine]

Could cryogenic freezing help by making
the resin brittle?

I suspect that at 77K the wood and horn lose some suppleness. The blade should be unaffected I imagine

 

[aporigine]

An hour in a 190 sous vide and a surprising amount of brute force has always worked for me. Except for the one time someone used the strongest epoxy known to man and then it was just destruction

Last time I tried brute force, things broke.

 

[tostadas]

It really depends on how it's adhered.

Friction fit: wood and mallet
Wax: wood and mallet
Hot glue: heat gun, wood and mallet
Epoxy: good luck trying to save it and reuse

The last type not listed above is the stuff I see used on high end Sakai knives. It's not hard like epoxy, kinda soft with the consistency of old chewing gum. I managed with heat gun once but it's an absolute b**** to remove. After that I just started destroying them.

There are probably solvents you can use to dissolve or soften the epoxy, but then you should ask yourself if you're comfortable with getting that on the handle of a tool that may come in contact with the stuff you eat.

 

[aporigine]

It really depends on how it's adhered.

Friction fit: wood and mallet
Wax: wood and mallet
Hot glue: heat gun, wood and mallet
Epoxy: good luck trying to save it and reuse

The last type not listed above is the stuff I see used on high end Sakai knives. It's not hard like epoxy, kinda soft with the consistency of old chewing gum. I managed with heat gun once but it's an absolute b**** to remove. After that I just started destroying them.

There are probably solvents you can use to dissolve or soften the epoxy, but then you should ask yourself if you're comfortable with getting that on the handle of a tool that may come in contact with the stuff you eat.

As a onetime lab chemist, “hold m’beer!”

I encountered one knife that had some weird black goo as the adhesive. It yielded just fine to boiling mineral spirits.

 

[Rideon66]

Last time I tried brute force, things broke.

First see if it is one of the ones tostada listed. You can use an oven for the hot glue if you don't have a heat gun. I like the hot glue easy to use and remove.

So I have not done it yet. I am slow at getting to these things and need to finish the handle to replace with yet, but I have a blade which handle epoxied on and got some advise from Oli on this. So if it is epoxy Here is his response.

'epoxy'. Boil the handle naked in a kettle for about five minutes and then pull it off in your hands whilst twisting slightly. You may need a couple of goes with the boiling. If its proving particularly tricky then try running the blade of the knife under a cold tap immediately after boiling the handle, whilst trying to pull it off. Epoxy is very strong, it makes other glues look like olive oil, but the best ways to break an epoxy bond are; heat, torsion, and shock temperature changes

 

[tostadas]

Also if talking heat, too much can warp, melt, or crack horn. Horn is not really a great material in my opinion.

 

[Rideon66]

I was thinking that about horn. It can get soft and messed up with too much heat. I have straightened horn scales on razors by heating them in boiling water then letting them cool in the position I wanted them.

 

[aporigine]

I was thinking that about horn. It can get soft and messed up with too much heat. I have straightened horn scales on razors by heating them in boiling water then letting them cool in the position I wanted them.

I’m gonna wager that hot hydrocarbon will give me leeway. Keratin is famously water-absorbent, so a dry process might let me closer to epoxy’s glass-to-goo phase transition without swelling or softening the horn.

 

[HumbleHomeCook]

If the handle is epoxied on and there is epoxy holding the handle together (ferrule) well then...

 

[aporigine]

If the handle is epoxied on and there is epoxy holding the handle together (ferrule) well then...

… then i’ll have to reassemble the handle. No great penalty for getting it off.

 

[Rideon66]

If the handle is epoxied on and there is epoxy holding the handle together (ferrule) well then...

You could boil in a bag to keep dry. I was thinking of trying this first on mine

 

[HumbleHomeCook]

You could boil in a bag to keep dry. I was thinking of trying this first on mine

If it's all the same epoxy, anything that loosens it in one place is likely to loosen it in the other. Yes, there are thermal expansion considerations I guess but I mean, if you're going to go this far, at a minimum you should be committed to losing the handle. If you don't then cool but if you do, you'll have gone into it with proper expectations.

And if you loosen the ferrule from the handle and there's no dowel, realigning things is gonna suck.

I reckon it's all possible, just saying I think one should temper expectations of the outcome.

 

[azn_knives_4l]

As a onetime lab chemist, “hold m’beer!”

I encountered one knife that had some weird black goo as the adhesive. It yielded just fine to boiling mineral spirits.

You would have fit right in with those FDA scientists that tasted everything from radium to arsenic to cyanide.