Wrist blade mechanism using an old CD-ROM mechanism

MattyNX

Unblooded
I used a DPDT momentary-contact switch. I had the switch concealed in the palm of my hand, connected to a ring that went around my finger. I engraved a clan symbol on it and called it my "class ring".

Actually, after I first built that setup, I changed to using two DPDT lever switches. One switch is velcroed on my index finger and extends the blades. The other switch is velcroed on my middle finger and retracts the blades. I did it this way because it's easier to press a subminiature lever switch than it is to press a large toggle switch.

I could post some pictures if that would help.




So you would recommend using 2 subminianture DPDT switches as apposed to the one singular switch? i would be really grateful if you would be able to post a few pics, also did you have to modify the motor housing to that it didn't take up too much space for the blades? (i've got a an old dead cd rom drive and i've dismantled it to get to the motor but it is pretty wide so i would either have to turn so that it's loner than it is wider, it's kinda hard to explain so i've posted a pic of what the housing and motor look like.

PICT0175.JPG


PICT0174.JPG
 
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Elkman

Blooded
So you would recommend using 2 subminianture DPDT switches as apposed to the one singular switch? i would be really grateful if you would be able to post a few pics, also did you have to modify the motor housing to that it didn't take up too much space for the blades? (i've got a an old dead cd rom drive and i've dismantled it to get to the motor but it is pretty wide so i would either have to turn so that it's loner than it is wider, it's kinda hard to explain so i've posted a pic of what the housing and motor look like.
Here are a couple pictures of how the switches are wired up. They probably won't explain a lot unless I post a wiring diagram, but I won't have time to do that tonight. Here are the pictures:
SwitchWiring-01r.jpg

SwitchWiring-02r.jpg


Basically, the + and - wires from the battery connect to the common terminals on the first DPDT switch (the one with the black velcro on it). The normally open terminals go to the motor to drive it in the forward direction. So, when you close the switch, the connection is made and the motor shoots the blades forward.

Here's the interesting part: The normally-closed terminals on the first switch go to the common terminals on the second switch. Then, the normally-open terminals on the second switch are wired back to the motor connection on the first switch, but in the reverse polarity. This means that when the second switch is pressed, the connection is made in the backward direction, and the motor pulls the blades back. Actually, in this picture, the wires have fallen off the second switch, so I need to repair them.

What happens if you press both switches at the same time? That blows up the entire known universe. No, I'm just kidding -- if the first switch is pressed, then the second switch doesn't get any power, because its contacts are now open. The motor will go forward in that case. This would all be easier to explain if I had a diagram, so I'll try to get one on here in the next day or two.

As far as modifying the motor housing goes, I had to cut down the motor housing from the CD-ROM pretty significantly so I didn't have any extra plastic getting in the way of the blades or making the gauntlet too big. Basically, I only kept enough of it to include the motor, the gearing, and enough to mount it to the blade traveler block.

great idea!!! and really well made!! are you painting it soon?
I painted it a year ago, not too long after I finished building it. I presented the costume at CONvergence 2010, a science fiction convention held in July in the Minneapolis-St. Paul area. I won Best In Show at the Masquerade with it.

Actually, I've abused it enough that I need to make another cast of the top of the blade housing. I dropped the gauntlet at the Klingon party room at MarsCon. (I didn't drop the gauntlet in terms of issuing a challenge -- a Klingon vs. Predator fight would be unpleasant. No, it just fell on the floor.) The top housing cracked in a way that's going to make repairing it a pain.

SwitchWiring-01r.jpg


SwitchWiring-02r.jpg
 

MattyNX

Unblooded
Here are a couple pictures of how the switches are wired up. They probably won't explain a lot unless I post a wiring diagram, but I won't have time to do that tonight. Here are the pictures:
SwitchWiring-01r.jpg

SwitchWiring-02r.jpg


Basically, the + and - wires from the battery connect to the common terminals on the first DPDT switch (the one with the black velcro on it). The normally open terminals go to the motor to drive it in the forward direction. So, when you close the switch, the connection is made and the motor shoots the blades forward.

Here's the interesting part: The normally-closed terminals on the first switch go to the common terminals on the second switch. Then, the normally-open terminals on the second switch are wired back to the motor connection on the first switch, but in the reverse polarity. This means that when the second switch is pressed, the connection is made in the backward direction, and the motor pulls the blades back. Actually, in this picture, the wires have fallen off the second switch, so I need to repair them.

What happens if you press both switches at the same time? That blows up the entire known universe. No, I'm just kidding -- if the first switch is pressed, then the second switch doesn't get any power, because its contacts are now open. The motor will go forward in that case. This would all be easier to explain if I had a diagram, so I'll try to get one on here in the next day or two.

As far as modifying the motor housing goes, I had to cut down the motor housing from the CD-ROM pretty significantly so I didn't have any extra plastic getting in the way of the blades or making the gauntlet too big. Basically, I only kept enough of it to include the motor, the gearing, and enough to mount it to the blade traveler block.


I painted it a year ago, not too long after I finished building it. I presented the costume at CONvergence 2010, a science fiction convention held in July in the Minneapolis-St. Paul area. I won Best In Show at the Masquerade with it.

Actually, I've abused it enough that I need to make another cast of the top of the blade housing. I dropped the gauntlet at the Klingon party room at MarsCon. (I didn't drop the gauntlet in terms of issuing a challenge -- a Klingon vs. Predator fight would be unpleasant. No, it just fell on the floor.) The top housing cracked in a way that's going to make repairing it a pain.


I've tried to look on ebay for DPDT lever switches but the closest i can get is slide switches or SPDT lever switches. Can the setup be done the type of lever switch i specified? i don't want to have to fiddle with slide switches especially if i'm wearing the costumed gloves which would make it virtually impossible to activate the mechanism. Can you recommend somewhere that would sell the switches needed?

If all else fails i suppose i'd have to consider asking you if you would be able to make the motor system and track for me for which i would pay for, just give me a price and S&H costs. that's of course if you would have the time.

Cheers.

I would like to mention that i've downloaded a pep for the shoulder cannon that i will be adding to my current design just to give it that little extra length and the rounded back part which seems to be the standard design. (Pics to follow in the next day or so)

SwitchWiring-01r.jpg


SwitchWiring-02r.jpg
 

papaz

Unblooded
Elkman..excellent work, great idea.
Quick question, are you able to run the old CD/DVD motor using a battery source?..never mind...went back on reading additional post and saw that you wired it to a battery..Cool..
keep it up - I look forward to see the complete project
 

Elkman

Blooded
I used a rechargeable 12 volt sealed lead-acid battery from Batteries Plus, something like this battery. Given that the motor takes 12 volts, this seemed like the way to go at the time, although eight AA batteries in series would probably have given enough voltage as well.

More recently, I've been building these mechanisms with a Tamiya motor/gearbox driving a gear against a fixed gear rack. The Tamiya gearbox has a motor that works on 3 volts, so it's much better suited to battery power.
 

Bo Skarr

Blooded
how did you separate the ejection from the container
I seperated everything but I need help getting the motor out
 
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