Sharp pointy things

[Maz]

Im going to try making some wristblades, for me and a friend.
I made these today (from cardboard woo!) because i was bored and i wanted to get a feel for them in real life. I used a template in Don Jarr's thread about his wristblades.

The finnished ones im hoping to make will probally be made from a metal (probally stainless) and be retractable using an electromagnet and a spring, the friend i mentioned will make the "casing" / the actual gauntlet.

 

[Dahdtoudi]

Those look wicked man!! Great job!! Question... how'd you get such a clean cut?? Every time I make a pair out of cardboard, the edges look like I was drunk when I cut them..

 

[Maz]

Question... how'd you get such a clean cut??

I used a craft knife, i find if you use sizzors it roughs up the edges and bends them a little, you also get loads of straight edges rather than a smooth curve.

Moral of story: Use craft knife

 

[Dahdtoudi]

Kool. Thanks man!!

 

[Maz]

Does anyone know what voltage you have to use with an electromagnet to get it to work off batterys? I tried it earlier with 1.5 volts (small i know but its all i had around the house) and it diddnt work, did try a car battery and the wire melted but it did permantly magnitise the metal rod i was using, so somewhere between the two...

Anyone know anything about electromagnets?

 

[esdain]

lol, you used a car battery???? awesome. stupid but awesome. also, if the car battery had worked you plan on strapping it your back or wheel it about on a trolley? i think even the workers ligh batteries you get on road cones would be too big, they are something like 24volts, i doubt a single 9volt would be enough but you could try 2. depends how easy the thing you are pulling slides to, bearings maybe, a greased rail perhaps? you'll need something

 

[Maz]

stupid but awesome. also, if the car battery had worked you plan on strapping it your back or wheel it about on a trolley?

I knew it would happen, i just wanted to have some fun (it only took 5 miniutes to make so why not?) i wasent counting on it earthing through my thum when it melted though...
If it needed a battery like that i would scrap the idea, a motorbike battery i could but up with perhaps... (hide it in the medkit!) i dont know i havent looked in to this too much yet.

 

[Ei luj]

esdain, all

Now you got me thinking......
I poked around Google looking for solenoids, etc. and ran across this....

http://www.firgelliauto.com/product_info.p...products_id=132

they have miniature linear actuators that run on 12v and take less than 2 amps... 1.5 inches per second on the fast one.

If thats too slow, maybe a spring to slide out and electronics to pull back....

---
Ei'uj

 

[Maz]

Thats a pretty good idea, i might run with that, spring out and electrics to pull back in, might be a bit slow though, dont know how you would get it to stay in without keeping them on. Its worth checking out anyway.

 

[vampss]

cool but what about the gauntlet

 

[Maz]

the friend i mentioned will make the "casing" / the actual gauntlet.

cool but what about the gauntlet

Chris you know perfectly well that that friend is you.

 

[Ei luj]

Thats a pretty good idea, i might run with that, spring out and electrics to pull back in, might be a bit slow though, dont know how you would get it to stay in without keeping them on. Its worth checking out anyway.

Electronics would only be active when needed, the mechanical part needs to tell the tron when to act and when to let the mech take over (not the BORG )

--
Ei'uj

 

[Maz]

Really?

Say i had it set up like this then; Spring launches them out to full length, actuators on, blades come back in, actuators off, blades stay in.

They would work like that then? If they do, how do i turn off the actuators locking mechanism to let the spring launch blades out? (if you havent guessed i havent had time to look up stuff on actuators, im in me tests at the mo..)

 

[Ei luj]

Q: how do i turn off the actuators locking mechanism to let the spring launch blades out?

Actuator off command could come via the trigger (in my case fishing line) when its pulled. Pulling it lets the spring do its job....

I wonder how big those hobby motors are... Rc control cars etc.

---
Ei'luj

 

[BANE]

you can also use curved scissors, as used in the radio contro cars/trucks and planes, very sturdy scissors, and shard can cut thru .060 lexan wich is pretty thick in the rc world, that's what i used to cut my proto blade out with fron a plastic storage caontainer lid, cuts easily around the curved edges, and can also be used in the straights, dubro makes them.

r/c car motors are 540 to 550 size cans, in the 1'th scale cars and trucks, and of course he brushless motors but not for this application, you can get smaller motors, ranging from 280 - 340 sized motor cansthese are much smaller motors and are used in the 1/18th scale and smaller r/c vehicles.


example of size of r/c car motors
do you know anyone that has children and have powerwheels? okay the motors on powerwheels vehicles are 550 sized motor cans, also used in r/c car and trucks, the cheap r/c vehicles you find at wal-mart usually carry a 280 sized motor, they just doll it up with over sizing the vehicle. your basic turns are stock can 27 turn an average speed and torque, and the motors go way slower down to 85 turns, which are used in the rc rock crawler vehicles, slow turning but very torquie. most of the motors i have mentioned above usually look identical, but the differences are in the winds(turns) and can size, lower the number on the motor the faster it will go, visa versa for the larger numbered motors, .

 

[DannyinTexas]

I was looking closely at P1, and there seem to be two "pistons" attached to the blades mid-point. I bet those are the actual mechanical extender/retractors. I also bet they come from some other everday device...

 

[Garo Predator]

Nice now put them on a gaunt