"Disassembleable" Knives?

[Dave Larsen]

Lately Lloyd Hale said something to the effect that if one knows the combination, his knives can be taken apart. This leads right into one of my biggest concerns with the knives I make: epoxy.

Some day, epoxy will fail. People talk about never having had epoxy fail them before, but obviously none of their knives are 150 years old... If I want my knives to really be worth their salt, they need to hold together basically forever. That means to me, no glue.

So I've planned my own New Year's resolution: in 2004 I'm going to start putting my knives together, as much as possible, with screws. No glue.

This brings up a couple of questions though.

One, how will I keep water, blood, etc out from under parts like the bolsters and scales.?

And two, what screws do I use? I need hardware, step drills, taps; but I don't have a clue what sizes to use.

So how about some suggestions what hardware, drill sizes, and tap sizes to use? And where to get them - ideally the same place?

I make full sized fixed blade knives, no folders just yet. I sure appreciate any ideas. Thanks,

Dave

[Dave Larsen]

A bit ago I realized part of my thread above might sound a bit arrogant. I sure didn't mean for it to. When I said none of our knives have been around for 150 years I only meant to imply that we don't know how good epoxy really is; I did not mean to question anyone's processes but my own. Sorry if I inadvertently offended anyone; please just chalk it up to me being dumb.

With respect,
Dave

[Darren Ellis]

Dave, I sure didn't read any arrogance in your post...just a definite concern. I too, am interested in this topic as well. Could you forward any private email replies with information to me as well? ...I would sincerely appreciate it!

-Darren

[Kevin Wilkins]

Dave, nothing is forever. The steel you use will eventually rust away to nothing, the grips will rot and fall off. Ever hear that saying, "This too shall pass"?

Unless you use some type of glue or gasket under grips, liquid will capilary itself underneath and the degeneration process will go a lot faster. Epoxy is one of the best choices because it does last a long time and hold up very well.

Bolsters can be soldered on, depending what type of material they are made of.

Screws will rust too. And some guy will eventually try and remove them with the wrong screwdriver and strip 'em out, etc etc.

You may use any size and type of screw which suits your design. Screws with Torx heads tend to allow more assembly / disassembly (esspecially in the smaller sizes) than socketheads, but fine watches still use slot and Phillips heads. Operator skill is always a factor.

Drill and tap gides are printed in most toolmakers handbooks. MSC Direct in the USA sells just about everything you can image to blow your tool-buying budget well into the next century!!

[george tichbour]

If you have ever replaced a handle on a 10 year old kitchen knife you will know how important it is to have the handle sealed in place instead of just pinned or riveted.

Epoxy has not been around for a long time to evaluate it's effectiveness over long periods but modern versions are definitely better than types from 40 years ago. Given a choice I will use a waterproof epoxy rather than leave the scales loose.

[Phantom23]

I have an Aitor Survival knife (7 inch blade) I purchased about 23 years ago. It has had a lot of use.

It's handle is some type of wood and it has three brass "bolts/screws" and a thong hole in the handle. Now it is a long time since I took the handle apart but my recollections are that they are similar to the "hidden bolt fasteners" advertised at Texas Knifemaking Suppliers. They are slightly recessed into the handle.

Unscrew the three screws and off the slabs come. But I have only taken it apart about 5 times. I do not know how it would hold up if it was being taken apart every week.

Maybe that's an idea to look at.

Phantom23

[Dave Larsen]

Thanks for the replies. I absolutely do intend to seal the spaces between scales/bolsters and the knife. I'm just looking for something that isn't as permanent as epoxy. I agree that modern epoxy would be better than the first versions, and in fact might reasonably be expected to last 100 years. Still, I'll feel better if the construction of my knives doesn't rely on it.

A couple things I've considered for a seal are beeswax or heavy grease. I used to work for a natural gas compressor line, and we had some grease that was incredibly stiff and tacky, used to seal valve parts. I've also thought about the wax that toilet drains are sealed with. That stuff is also very stiff and tacky. The issue with any of these materials would be the potential to "leak" in hot weather, or to possibly contaminate game. Not cool.

As to screws, I'm hoping to get some concrete numbers so that I don't have to experiment much. I don't have the wherewithal to buy too many unneeded parts and tools.

Using smaller screws would subject them to more wear, like Kevin suggested. I'm thinking along the lines of something more robust than is used in most folders you see. But this means that to get enough threads in the metal the screws would probably have to be offset from one another, leading to design issues. I think that's probably preferable to having the parts wear out after having been taken down a couple times, but sure is something to think about. Particularly on bolsters where it would be more noticeable.

Well, this is as far as I've gotten. I do appreciate the comments and I hope you all keep them coming. Darren I'll be sure to share whatever I learn on the side with you too. (Thanks for your thoughts on the burner issue, now you have me second-guessing myself! )

[Dragon cutlery]

for small screws if you are looking at a size make shure you are geting the fine thread you will get more treads per inch and you will get better grip and less slop with the same size screw get a knife supply catalog and look trew what thay have thay usaly have the prity screws and in small to mediem sizes that way it wont look like your knife was asembled by a hardwere store employe on his lunch hour the sizes i have used in the past are 2/56 3/48 and mostly on fixed knives that i wanted to come apart for cleaning i keep whanting to make one the some one wants a fixed blade and i put it on hold agen 4/40 are ok but if you can find a 4/48 it would be more threads to hold to stuff


heres a pic of one with screws holding the scales on the bird hook slides out and i desided it should come apart after use for cleening the track
http://dragoncutlery.bravepages.com/birdtrout.jpg
sorry about the pic i was still geting used to the new lens at the time

[Shakudo]

I personally don't use expoy on my knives.the knife i make is a reproduction of an early 1800's cartouche knife.my customers want a product that is made as close to what was done in 1800 as possible.you must also consider how your knives will be used,is it going to be in a showcase or a work knife that will be used as a tool.i have added a link to an ebay auction of a purported knife from the late 1700's,if it is authentic ,it looks good for 200+ years and no epoxy.http://cgi.liveauctions.ebay.com/ws/...tem=2207217673

[OutWest]

Varnish might give you the seal you are looking for, dries hard and doesn't melt away in the sun. Maybe one of the traditonal types from a woodworking specialty supply would be the best option and certainly less "plastic" than the Poly types on most store shelves. There seems to be a lot of old furnature around with varnish still in place.

[Lloyd Hale]

Kevin is right, Nothing lasts forever and nor should it...Some of the knives I made back in 70's are little time capsules.. meaning..when the stag or micarta scales come off the owner will find that I scribed on the tang what I was thinking about at the time I put the scales on the knife... what was in the news of the day etc... I still do it .... Dave , if you use screws you incourage people to dismantle your knives...this inturn will damage the screw heads and all sorts of bad things happen... Some of my knives will have 30 to 40 seperate pieces each inter-locked starting at the front collor and going back to the pommel....
When I say they will come apart if you know the combination, this is true but rest assured you have to know where the epoxied one is and how to unlock it.... I wouldn't worry about the life expectency of epoxy We will all be dead and gone many many years before this happens and anyway then if it does happen the Collector who owns the knife can do his part by restoring it...and maybe sharing your thoughts....

[SharpByCoop]

For whatever reason, screws holding together parts on a fixed blade doesn't appeal to me. It's fairly unconventional, except for some less expensive composite material handles on combat and tactical knives But I think Dogman (Bob Doggett) is the only one I'm familiar with whose fancy knives have screws holding them together. (And I would like his even more so if they weren't done this way. But that's me.)

But that also may be the opinion of your prospective customers. I don't want to dissuade you, but be aware of what affect you might have on your current future, in spite of the future 150 years from now... !

Food for thought.

Coop

[Don Robinson]

[QUOTE]Originally posted by Dave Larsen
[ I'm thinking along the lines of something more robust than is used in most folders you see. But this means that to get enough threads in the metal the screws would probably have to be offset from one another, leading to design issues.

You don't need to offset the screws. Use 1/8" or 3/16" straight pivot pins that are used in linerlock folders. These pins have a 2-56 or 4-40 internal thread all the way thru.

Drill the tang thru and part way into each scale from the inside. the pins are 1/2" long, and will extend thru the tang partly into the scale on each side. Driil the rest of the way thru the scale holes with a drill that's clearance sized for the screw, then counterbore each hole in the scale from the outside to fit the screw head.

Use Torx button head screws.

Use the same method for the guard.

I've built weapons this way for soldiers and other people who want to dis-assemble the knife for cleaning.

For an example, go here.

http://home.rgv.rr.com/donrob/Folders%20page%202.htm


Look at the knife at the bottom of the page.

There are more on the "Fixed Blade" page.

[Dave Larsen]

Don that's exactly what I had in mind. What are your screw sizes? Now that you mentiion it I've heard about the pivot pins...called something else I think but the same thing. Thank you very much.

Lloyd and Coop, your comments are well taken. However, I still care what my stuff is going to be like when I'm dust! But the thought of someone restoring the knife is a very pleasant one - the best one yet, thanks Lloyd. :cool: I have to say, the "combinations" for taking apart your knives sound a bit like those Chinese puzzles we had when we were kids. I sometimes had a fit of a time solving those things...

I've never written anything on the tang of a knife. That's another interesting idea, and something I bet other artisians do. I once put a message inside the chimney of a doll house I built for my daughter...sort of the same thing.

Coop my interest is not esthetic, it's pragmatic. It would not work for every knife for obvious reasons - can't see screwing the scales on a SF bowie! A customer would certainly get what he asked for, and possibly the ability to take a knife down should be an option - or pins an option? I'm not entirely averse to the idea of using epoxy - just to relying on it to hold the knife together.

"Loveless" bolts over epoxied scales would probably be the ideal combination for longevity. For that matter, Micarta would probably beat most any "natural" material hands down (but then I think, this mammoth ivory is 10,000+ years old!). I like the idea of using varnish or similar for a seal too. The Neo-Tribal guys have various recipies for "cutler's resin" that has apparently proven stable over very long periods of time.

In the end I guess it all comes down to what the knife is going to be used for, what is esthetically appealing, and what the maker and customer expect from the work in terms of its life expectancy. Personally I want it all to hold together as long as the molecules in the steel are hanging in there. It's true many "primitive" knives have lasted hundreds of years, and that is exactly what I'm looking for. If the eBay knife Shakudo showed us is really that old, that maker had his act absolutely togther!

Thanks for all the great discussion,

[Don Robinson]

Originally posted by Dave Larsen
Don that's exactly what I had in mind. What are your screw sizes? Now that you mentiion it I've heard about the pivot pins...called something else I think but the same thing. Thank you very much.

You're welcome, Dave. For a full shank knife, I usually use the 1/8" pins with #2-56 threads. I use stainless Torx button head screws with them.

These pins and screws are available from, If I remember correctly, S.R Johnson, whom you may know, since he moderates this forum, Koval, Texas Knifemakers Supply, Halpern Titanium,and others. They are made for linerlock folders.

You can get the screws with 24K gold plating if you like.