Introduction: SA OTF Xiphoid MK IV - Arm Mounted Blade

 Single Action Out the Front Xiphoid Mark Four

This is the fourth xiphoid I have made. It's pretty simple, and works very well.
This is NOT meant to be from Assassin's Creed! Though I love the game, this is UNRELATED.
Made from a drawer slide, 5 bolts, 9 nuts, strips of homemade faux leather, 4 keyrings, wire, springs, and a ring.

Thanks to Nightshade for the latch design.
Thanks to NightHawk22 for the awesome song.
Thanks to SINZA for his epic forum, you rock! 


SlashingAssassin made it! (author)2015-07-29

if you make another how much?

Udit Mathur made it! (author)2011-03-04

can you make a retractable blade??spring loaded or motorized any will work for me

Techie_Gary made it! (author)Techie_Gary2012-07-29

wanna see my concept??? its a design that allows minimal force to eject or retract a very long object, like the blade. Details are on my instructable:

Hope i helped you......

Kaiven made it! (author)Kaiven2011-03-05

I can, though I can link you to a tutorial that has already been done well.

Udit Mathur made it! (author)Udit Mathur2011-03-06

send me the link

Kaiven made it! (author)Kaiven2011-03-06

Udit Mathur made it! (author)Udit Mathur2011-03-06


curvy77 made it! (author)2011-12-05

assasins creed!!! i to am planning my own design frm that game. >=) i am working on the wrist pistol. i have the general design and have come up with a (hopefully) safe way of firing a revolver round. withou fireing off my hand too but we'll see.

BLR25 made it! (author)2011-10-25

is there any way you could make me one, i would buy it if you made it

jumper17 made it! (author)2011-09-24

Could you post specifics on either where to salvage a latch like the one shown in the video, or how to obtain/construct one? Thanks. (P.S. What is that EPIC music played in the sped up section?)

Kaiven made it! (author)Kaiven2011-09-27

I just cut it out myself from scrap metal. It's shaped like an L with a hook.

Lt. Duct Tape made it! (author)2011-07-15

Any idea where you might have gotten your springs? I used 2.4 pound springs from home depot, but they turned out to be made out of crappy material- Stretched out like nobody's business.

mulletman6 made it! (author)2011-06-03

What width draw roller do you use?

Kaiven made it! (author)Kaiven2011-06-04

Umm not sure, all the drawer slides are the same width from the hardware store...

mulletman6 made it! (author)mulletman62011-06-05

Ah fair - It looks like quite a wide one, so i shal have to have a look for a bigger one :)

knights1224 made it! (author)2011-03-29

I like it

some tips / things you could do different:
- have some sort of arm protector, that looked kind of uncomfortable with the bare screw/nuts against your arm
- have it to where you can stab and slash with out the blade retracting, because a real hidden blade can do that, so maybe have a locking pin that can be removed [see below for details]
[see above for unnecessary use of brackets with words in them]
possibly switch the ring to your ring finger and have a locking pin wire and ring on your pinky-finger. so somehow you could bring out the blade and keep it from moving when you stab, and you could also bring it back in when you wanted

I would buy a wholly completed one

alcemy_FTW made it! (author)2011-02-15

what could i use for the blade?

Kaiven made it! (author)Kaiven2011-02-16

Anything... depends on what you have.

sithstalker made it! (author)2011-02-15

av just made 1 from shin gaurds havin a bit troulbe with the latch

lilparis47 made it! (author)2011-02-02

fitting music

larslovespeace made it! (author)2010-09-05

could you post more of the specs of the design for those who want to make it? - even a project for DIY purposes.

Kaiven made it! (author)Kaiven2010-09-05

Specs like what? Everything is shown and described in the video.

EwwieImp made it! (author)EwwieImp2010-12-24

It would be helpful though if you could put the exact things such as bolt size, length, etc.

Kaiven made it! (author)Kaiven2010-12-24

I never designed it on specific measurements. EVERYTHING has to be adjusted according to materials and the wearer. The drawer slide is 10 inches, that is the only fixed measurement.

larslovespeace made it! (author)larslovespeace2010-09-06

I guess your right- I will just try to fabricate it based upon video

Sarthex made it! (author)2010-12-21

i think this is the first instructable i ever favorited O.O
awesome job man

Kaiven made it! (author)Kaiven2010-12-21


11richie21 made it! (author)2010-09-29

Where can I get or how can I make the release "thing" (metal piece that releases the blade)?

PerfectPantaloons made it! (author)PerfectPantaloons2010-12-16

i think the word you're looking for is a "latch" and you could always bend some 8 gauge heavy duty wire to fit

Kaiven made it! (author)Kaiven2010-09-29

Just cut an "L" shape from a piece of thick sheet metal and make a "barb" on it, like seen on a hook.

pkthunder made it! (author)pkthunder2010-12-14

hey just wondering... i have been looking for instructions on how to make one of these. could it be possible for you to make a tutorial?

Kaiven made it! (author)Kaiven2010-12-14

I wouldn't be able to do much besides another disassembly.

11richie21 made it! (author)11richie212010-10-02

Thank you that help! I made the piece and actually made one of these with a blade but i was going to ask how much tension your springs have? I used only one because it was around 11.5 lbs but around the same size as your larger spring. the spring I have makes it hard for me to put the blade back in :( Thanks

deathbygrandma made it! (author)deathbygrandma2010-11-28

you could just make it out of a piece of thin wood, it would work just as well and would be easy to replace

(YOUR N made it! (author)2010-11-07

Hey hey it's me again I'm shocked y arnt u wearing
That cool :) t shirt great Ible do

IneXtrikabul made it! (author)2010-10-11

Would it be too much trouble to make a tutorial for this thing? It's too awesome to not want to make!

greatnameless1 made it! (author)2010-09-16

How much should I expect to pay if I want to build one of these?

Kaiven made it! (author)Kaiven2010-10-01

I paid about $3, because I had most of the stuff. I'm not sure how much it would cost to buy all of the parts.

knex 711 made it! (author)2010-07-21

when it has a blade how will it retract automatically other things ive seen

Kaiven made it! (author)Kaiven2010-07-22

Sorry, I do not understand your comment. Please use punctuation and complete thoughts.

Pumpkin$ made it! (author)Pumpkin$2010-08-19

Hey CCK!! I love the design, it seems like retracting is the only final step, and I had an idea, you could take a Velcro ring, attach it to your shoulder, and run a cable down to the blade-deployment-mount (thing) and Extending your arm downwards could retract it and lock it into place!!

Kaiven made it! (author)Kaiven2010-08-20

An idea, yes, but I prefer relying on just my hand and the mech. Involving my shoulder brings complications when jumping over buildings. You understand, yes? :D

im_madman made it! (author)im_madman2010-08-05

What he means is..."When there is a blade, how will it automatically retract like other things ive seen?"

Harpes1 made it! (author)Harpes12010-08-14

its an out the front blade which from what i gather means its only powered on the way out, if you want one that can go both ways easily a gravity blade is probably best, but even then it's not automatic, fully automatic (out and back in again) like in the game are quite fiddly to make and are less reliable unless done correctly

apocolips85 made it! (author)2010-07-28

can you show us a video of how to mount the front lock then please???

flashcre8or made it! (author)flashcre8or2010-08-11

If you go to his youtube channel he has an earlier model of the hidden blade. That blade had a locking mechanism. Maybe you can figure it out and make it? Good luck!

Rokko8652 made it! (author)2010-08-05

So you ARE cowscankill from that forum. I was this close to asking you if you were. Anyways, very nice design. I plan on starting one that will be pretty much a clone of Nightshade's gravity Xiphoid.

Kaiven made it! (author)Kaiven2010-08-06

Good, always a nice place to start.

kidmosey made it! (author)2010-07-31

Now, you need to make it auto-retract, too. :D Not sure how to do it using strictly mechanical means, though.

Kaiven made it! (author)Kaiven2010-08-01

There is a way... look up double action out the front knives. Many switchblades use a similar design.

About This Instructable




Bio: AKA Roborovski, and Cowscankill for several years. I'm a mechanical engineering undergrad.
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