Open back design: Why does it earn praise?

[Bolster]

I see a lot of positive mentions regarding "open back" knife designs on this forum, such as the Sage, the Yojimbo, the Military, etc. I don't understand, why is open back design held in such high regard? (Or is it?) What are its advantages and disadvantages?

[amen74]

One advantage is for easier cleaning of the knife.

[A.P.F.]

No disadvantages that I have discovered and as Amen mentioned, it is easier to clean.

[The Deacon]

Some folks feel there's less chance of debris getting caught in the handle. That is probably a valid point with hard use knives carried afield. Others feel there more chance for foreign objects to either damage the edge or get wedged between the blade and handle. That is probably a valid point for knives carried in a pocket with other items like keys and coins. Biggest disadvantage for me personally, is that open back construction is incompatible with the front lock, and that's my lock of choice. :D

[Brad S.]

You actually lose quite a bit of stifness in the handle with an open back design. Allowing flex between the two sides. That said. Some of the most hardcore knives and knifemakers I know use open back. I personally like the lightwieghtness of it. I know my cricket's blade gets some damage from coins.

Maybe Sal can chime in here and explain some things we dont know.

[dalefuller]

I spend as much time in the outdoors with my dogs as I can. Holidays for us are all camping/hiking, so my knives do get used outside, sometimes in dirty conditions. Open frame knives stay cleaner to begin with and are easier to clean when necessary.

The fact that I prefer open frame knives probably has a lot to do with the fact that I also prefer full liners. As Tricod mentioned, an open back knife loses some rigidity without full liners and I like my knife handles to be rock solid. I don't ever carry anything in my knife pocket except my knife, so change and keys are not a problem for me with an open frame knife.

[Jeff Tanner]

I'm betting the primary reason for the design choice in the first place is for weight reduction.

A full length stainless back spacer is tough to beat for maximum stiffness factor. The D'Allara is a beautiful example...one uninterrupted hunk milled stainless from the bolster right round the butt.

[Agent Starling]

Big knife w/out the heft is my guess...makes the new Superhawk a big knife without the clunkiness factor...

Agent Starling

[Simple Man]

I much prefer a closed back because as Deacon said, my keys get carried in the same pocket as my knife and I have hsd the edge destroyed before just riding in my pocket. I even made a cover of sorts for the end of my Millie back when I carried it to keep the keys off the tip.

The G-10 (and even SS) E4 solved many of those issues for me.

[huugh]

Some folks feel there's less chance of debris getting caught in the handle. That is probably a valid point with hard use knives carried afield. Others feel there more chance for foreign objects to either damage the edge or get wedged between the blade and handle. That is probably a valid point for knives carried in a pocket with other items like keys and coins. Biggest disadvantage for me personally, is that open back construction is incompatible with the front lock, and that's my lock of choice. :D

Well, if you look carefully inside the most lockbacks, you will see there is quite a gap between lockbar and liners, so the dirt can easily get there (indeed, in most cases, if there was no gap, the lockbar would get stuck). However, with "closed back", i.e. full backspacer, there should be no gap. And I still think e.g. Military would deserve a full backspacer - like this one (unfortunately, not mine ):

[brj]

Both open & closed back construction folders can be cleaned equally well, but when you do rinse them with water the open back allows for faster drying.
I prefer open construction because I can avoid certain possible cosmetic flaws this way (the backspacer is usually made out of delrin or some cheap plastic and it may not be perfectly flush with the scales) and because it helps me identify burrs faster (through the open back the light reflects only from the cutting edge and not from the whole blade). On the other hand, I carry only my knife in my RF pocket, where there isn't much of a chance of some coins/keys/debris ruining the blade, so open construction makes the knife a little less bulkier, aka 'better'.

[RIOT]

I see a lot of positive mentions regarding "open back" knife designs on this forum, such as the Sage, the Yojimbo, the Military, etc. I don't understand, why is open back design held in such high regard? (Or is it?) What are its advantages and disadvantages?

i actually agree, im not really into it, the sage & the superhawk the design doesnt work for me, im too old fashioned and like spydercos roots

too each their own

[sal]

I guess I have to agree with all that has been said. Advantagaes and disadvantages. Funny how that happens.

The design of a product will often have parameters that are connected to "basics" in the design of those products. In the world of knives, those basics would include:

Blade size - often decided very early in the design concept.
Lock type - which can determine design limitations such as with a back lock.
Purpose - determines materials and stength requirements of those materials.

In the case of open backs, for my own designs, I'm generally getting rid of weight, or as Colin Chapman would say: "add lightness". That's why we've gone to skeletonized liners in our models, especially the lock-backs which require a spring-holder, which becomes a full back-strap.

In these hi-tech times, ridgidity is not a factor. We can make it as ridgid as is necessary for the design. At 4.28 oz (122gms), The Superhawk offers strength, a 4mm thick 3.5" blade, full ergos, clip and lightness, and it's open back.

thanx for the input. It;s good information. I think I'll try a synthesis on the next open backed model.

sal

[SoCal Operator]

Sal, I'm really glad you're able to quote Colin Chapman.

[rlw1979777]

Weight. It reduces its weight by a lot. Look at the difference in weight between a military and a manix.

[jujigatame]

Sal, I'm really glad you're able to quote Colin Chapman.

I got a kick out of that too. Of course, when thinking of Chapman at the same time as Spydercos the next logical step in my mind was...a knife with handles sporting the classic John Player Special livery from the Lotus grand prix cars. That's what happens when two of my primary interests collide.

[Detdaddy]

It's funny this question was posted. This week I was playing with several different knives and comparing what I liked most about each. One of the things I noticed about most of my favorites is that they are open back (Military, Para, Dodo, Spin, Cricket, Yojimbo). I can't say that that alone is what makes them some of my favorites. But I would say that the weight (or lack of weight) is one of the reason I prefer these knives over some others.

I started looking at some of the closed back and tried to imagine how they would be as an open back, aside from the lock issue. My Manix and Mini Manix are also favorites of mine. Those two I would not want changed. There are days I don't choose to carry them due to the weight. But when I do pick one of them to carry, I like the weight of them.

So I guess weight is one of the top reasons I like them. But I do like to vary, depending on the task and clothes I'm wearing.

Oh, and does anyone else think a G10 flat grind Endura and Delica would be sweet as an open back?

[Ian UK]

Cant say I had given it much thought till this thread started I only have 2 open backs both Microtech Socom Elites and as I say had not thought much about it but I have just realised over the last few weeks I have been constantly cleaning out my Native (granted 1st gen **** that I just use for parcels and boxes) as it has been getting clogged up on the inside between the closed balde and back plate. Not that its a hardship!

But I can now see the logic and disadvantages in an open back. :)

[Capt. Carl]

I work a lot in the field on a farm. It gets pretty dirty and open backed knives like frame locks always seem to work the best and keep nice and clean. All I need to do to clean it up a bit is give it a quick blow through the scales and I'm done!

[Slatts]

Can't say I've given much thought to the pros of open back before this thread. My favorite open frame knives are my sebenzas...they are just hard to beat. My Benchmade 690s are just phenomenal and they are classics too. The Sage from Spyderco that I carry is destined for a good ride I think.

I like a good solid back knife though. Looking at my recently acquired green Manix makes me like it all the more. It's done so well that the spacer and scales are completely seamless. Looks like one solid piece of steel there in the middle. Very tight tolerances on classic Spyderco.