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Specter Engineering

At Holt Bladeworks, we incorporate wide variety of engineering disciplines in conjunction with the best materials to produce a world class knife at a fair price.  Every detail of the Specter has been carefully crafted to meet this goal.  We do not mean to brag, but as the potential next owner of this gentleman's flipper we think you should know:

  • We utilize the highest quality of blade materials, whether that be Damasteel or Bohler M390
  • While we maybe a gentleman's folder the strength of our designs place us squarely in the bombproof  tactical flipper category.
  • We designed our pivot interface to tolerate the large lateral and radial forces that destroy weaker, hidden stop pin designs.
  • All of our fasteners come from the industry leader in folder hardware manufacturing.
  • Our shop dog claims this is the best knife ... ever.


The Specter specifications are as follows:

  • 3.6 inch blade
  • Blade steel hardened to 61C with cryogenic treatment
  • Precision sharpened blade
  • 8.125 inch over all length
  • 3.6 oz weight

Pivot Design

The hidden stop pin is a common pivot design, that is mainly popular due to its ease of manufacturing.  This design typically includes a stop pin that is pressed into the handle, with a frown shaped travel path cut out of the blade.  This design makes the blade incredibly weak - especially to lateral loads - and predisposed to fracturing.

 Common Hidden Stop Pin Design

Common Hidden Stop Pin Design

The lack of cross sectional thickness is an obvious reason for this weakness, but this issue is further compounded during the heat treat process.  To obtain the right hardness, the blade must be taken from around 2000 degrees to room temperature within a very short period of time.  The frown feature creates an unfavorable ratio of volume to surface area, which means it will reach room temperature much faster than the rest of the blade.  This rapid cooling results in a brittle pivot cross section that is prone to fracturing and possibly failing even under moderate use.

 Specter Pivot Design

Specter Pivot Design

The Specter was designed to be much more than just a letter opener.  Its' pivot is built around a quarter inch, hardened, 416 stainless axle, and its' design is reversed from the more common approach.  It uses a radial  or floating stop pin that is pressed into the blade, with a travel path milled on the inside of the handle.  This design choice maximizes the blades cross sectional thickness, which greatly increases lateral strength.  The smaller amount of surface area and greater volume means it is less susceptible to brittleness from the heat treatment process.  For those of you who require a knife that is more than just a letter opener, the Specter is designed to be up to the task.  



 Specter Detent

Specter Detent

The detent is the heart and soul of a flipper.  It is responsible for the speed and ease of blade deployment.  Months of design work went into perfecting the detent mechanism for the Specter.  The initial design used a ceramic ball, which is a popular choice among many knife makers.  When tuned properly, this design works well, but the results are not especially consistent.  Changing the depth of the ball - by even a thousandth - can have a dramatic effect on the flipping action.  This inconsistency between knives makes it a clearly undesirable design choice.  

Specter Lock Bar Inline with Handle

The current production design is an integral detent and locking system.  The Specter's detent is 3D machined directly into our hardened 440C (bearing steel) locking insert.  Machining the lock and integral detent hemisphere together means every Specter flips exactly the same. 

An added benefit of this design is cleaner visual lines, because the lock bar is kept inline with the rest of the handle.  The end result is a knife that has a lightning fast flip and a vault like lockup.  There is no substitute for proper engineering.

It was recently brought to our attention that our integral detent is very similar to that of Brian Nadeau.  We have been in contact with Brian about the similarity and have discussed the development process we went through.  The similarities were unintentional, and just a result of our own development process.  We do believe it is further evidence of a solid design when multiple people end up in the same place.  That being said, we are reworking our detent and locking system to avoid any concerns regarding duplication of work.  Rest assured, the next design will be just as good as our current.


Lock Mechanism

There are many ways to design a lock on a folder, and the most common approach on lower quality knives is to use the face of the titanium lock bar.  There are three main problems with this design.  The first is that a titanium and steel interface will suffer from galling.  Overtime, the titanium will tend to smear and snag on the lock face of the blade, producing a catchy feel.  A slight variation to this design is to apply a thin layer of carbide - carbidizing - to the titanium lock bar. While this does solve the galling issue, it does not address the other two issues with this design.

Using Titanium Lock Bar for Locking Mechanism

Lock Bar Recessed Into Handle

The second issue with this design is that the correct angle cannot easily be cut on the face of a titanium lock bar.  With this design, the titanium lock face is a 90 degree angle, and the blade lock face is machined with a slight curvature to accommodate the poor fit.  The sharp 90 degree angle creates a very small point that will absorb all of the force required for locking, and that force will cause it to wear prematurely.  This wear and compression of the titanium results in a lockup that becomes progressively late, and is what drives the need for early lockup on folding knives.  

The final issue with this approach is that there isn't a reasonable way to keep the lock bar inline with the bottom handle when closed.  When closed these folders will have a lock bar that is recesses into the handle until it makes contact with the knife.  While this does not affect the performance of the knife, it is unsightly and avoidable.  

 Specter Lock Faces - The angles are close to identical, but the angle on the handle lock face is slightly bigger.

Specter Lock Faces - The angles are close to identical, but the angle on the handle lock face is slightly bigger.

Instead of designing the Specter to accommodate these issues, we have chosen to simply design the issues out of our knives.  We insert a hardened 440C stainless steel lock and integral detent into the handle lock bar.  This solves the galling issue and it does not wear in any significant way.  Additionally, it allows the proper lock geometry to be machined on the lock face.  Finally, we use a integral detent pad to keep our lock bar perfectly aligned with the handle.

This means that the Specter will always lockup in the same place, and it will not stick when unlocked.  Most importantly, it means that the lock geometry will prevent it from unlocking unexpectedly.  All of this ensures a safe and solid lock up that does not require any break in time.



 Specter handle with lock bar.

Specter handle with lock bar.

What good would a world class blade be without some spectacular handles to keep it safe?  These handles have been thoughtfully designed to be ergonomic without hot spots, and are definitely up to the task of protecting you and the blade.  One common hot spot,on a frame locking folder, is near the lock bar cutout.  The Specter employs a shielded lock bar cutout to remove this annoyance.  Additionally, all handle edges are chamfered to give an all around smoother and more polished feeling.  


Ball Bearings and Washers

The Specter blade rides on caged ball bearings that are either 440C stainless steel or ceramic.  Hardened and polished washers are inserted between the titanium handles and the bearings.  This is important for a couple of reasons, the first being that the bearings are considerably harder than titanium.  With continued use, the bearings would quickly destroy the uniform surface on the titanium and degrade the smooth flipping action of the knife.  The second reason is that the washers provide a smooth, consistent surface for the bearings to roll against.  This same surface cannot be reproduced by a mill with titanium handles.


Blade Material

All Specter blades are made using only the highest quality and best suited blade material.  Selecting the right blade material is all about finding a balance between edge retention, corrosion resistance, and hardness.  The Specter's primary blade material is the M390 by Bohler.  It is classified as a Super Steel, and based on its' balance of edge retention, corrosion resistance, and hardness it is undeniably one of the best steels currently in production.  

Damasteel blade material is an option available in our Prestige grade Specters.  Like the M390, Damasteel is a stainless powdered metal.  A Damasteel blade has good edge retention, and corrosion resistance, but where it really stands out is its' raw beauty!  This steel has some of the most interesting patterns of any stainless Damascus.



All hardware, specifically pivot pins, bearings, washers, and screws, is purchased from companies that specialize in making it.  This allows us to focus on the areas that we specialize in - making wicked smooth flippers with rock solid engineering behind them.  We believe this directly benefits you as the consumer - you get the product faster and at a lower price.