A coil gun missing part problem

[IanP]

To fully charge 5000µF capacitor through 1kΩ resistor you will need roughly 5 * R * C = 25s .. see picture below ..

If there is no voltage on one or more of these caps check SCRs as they may be ON and current through 1kΩ resistor will be enough to keep them ON .. If you have an oscilloscope take a look at C5 (SCR2) and C8 (SCR3) on power on ..
BTW, which caps are not charged: C3 or C6/C7?

Try this: disconnect SCRs (anode) and measure voltage on caps ..

Regards,
IanP

 

[Terminator Electricity]

hey man , one more question

if we decided to weld the project

where can we find the circuit suitable for welding

in order 2 print it on the board ?

 

[IanP]

"welding" <=> "soldering"
Is this what you have in mind?

Regards,
IanP

 

[Terminator Electricity]

yes man

i have told that i should have a circuit buid on eagle or something in order to print it on a board

but i dont know how 2 do it

how can i have it ?

 

[Terminator Electricity]

any one ??!!!!!

 

[Terminator Electricity]

plz i need a help with the coil gun

wen i press the trigger , the capacitor is discharged , but the projectile (nail) is not even moving

wat could be the problem

i used the coil at 4 cm long , one turn

note : the capacitor charges untill 27 v

plz help me fast , the engineering day is approaching

 

[IanP]

Was the cap charged to 27V?

If it was, and you had discharged it through that coil and nothing happened then somethnig has to be wrong with the coil ..
5000µF at 27V is a lot of energy ..

Regards,
IanP

 

[Terminator Electricity]

my coil was 4 cm long with one layer

the diameter was about 1 mm

is there any thing wrong with that ?

 

[Buriedcode]

Hi,

my coil was 4 cm long with one layer

the diameter was about 1 mm

is there any thing wrong with that ?

Not entirely sure what you mean. With that cap charged, as IanP siad, thats a fair bit of energy. What determines how powerful the magnetic field is is current and number of turns. Although, even a few turns around a plastic tube should make a nail near it twitch.

The more turns you have, the more resistance the coil has, the less current can flow (I=V/R). Its a careful balance, so thick wire would be a good idea, to lower the resistance, and allow for lots and lots of turns. Maybe gauge #28?

1mm diameter? of the wire? or of the entire coil? Thats VERY small for a coil in this sort of application. I would put together a simple 'test' coil to check that your circuit is working correctly......THEN you can design a coil for your app.

An obvious thing to check would be, is your projectile magnetic? Most nails are iron, so that shouldn't be a problem. Also, connect your coil to a 12V supply, keep the current low, say, 1A. Now you have a solenoid, move some iron things around it to check if the field is there/how strong it is, you also might want to check that the coil is actually conducting

If you've tried the above, and it makes a good solenoid, a decent electromagnet, then the problem is with your circuit. The cap may be disacharging via some other path.

Is the coil wrapped around a non-magnetic former? I can only assume you want a hollow coil, with a nail just outside of it, so that when you discharge your cap through the coil, the nail is pulled into the coil and thrown out the other side. I once used a spool of gauge 28, I bought from an electronics shop. Its the spool the wire came on, I just soldered the wires to my circuit and let her rip.

Some examples of what your coil should look-like/do:
http://www.global-defence.com/1997/High-speed/CoilgunLG.jpg
**broken link removed**
http://www.sampson-jeff.com/rsoh/010420/rsoh05.jpg


So, just to recap, some simple checks you can do:
Check continuity of coil.
Check power of magnetic field with the coil carrying DC
Check if projectile is magnetic (although, an aluminium ring WILL move)
Check diodes around the coil, one might have blown and be shunting the power, bypassing the coil.

Once you have a working circuit, that can create a magnetic pulse, then you can worry about your 'ejecter seat' mechanism.

I hope this helps in some way. I'm sorry if I'm asking questions that are obvious, or have been asked before, but once I get a good idea of what you want, and what your coil looks like, then I can try and help you solve your problems.

 

[H_u_n_t_e_r]

the capacitor is discharged , but the projectile (nail) is not even moving

wat could be the problem

projectile should be stay near at input of the coil not inside

 

[Terminator Electricity]

here is my coil

**broken link removed**

**broken link removed**

**broken link removed**

should i have more number of turns ? longer coil ? etc .............

 

[IanP]

My gut feeling is that you should have about 5-8 layers and ≈30 turns per layer ..

Regards,
IanP

 

[H_u_n_t_e_r]

longer coil means low discharge current ..so.. slow projectile speed 4 layer enough i think

ps: 640x480 enough for picture res.

 

[Terminator Electricity]

hey again

10x 4 the advise about the coil , my new coil works

i just now have 2 adjust few things (n,l etc)

i have now a new problem

the transmitter and reciever i have bought have low range (max of one cm appart)

wat can i do to extend the range ?

10x,

 

[Terminator Electricity]

i was advised to connect some emmitors im parallel

any other suggestions ?

 

[IanP]

Having 2 or 3 emitters working together may help ..
But don't connect them in parallel, each of them should have its own "+5V" resistor ..

Regards,
IanP

 

[Terminator Electricity]

10x 4 ur help , the coilgun has worked very good infact

now all i have 2 do is to to print the map on the board using eagle and then begin soldering

but i have faced a little problem using eagle , especially with the timer circuit ,

**broken link removed**

i have faced many trobles connecting ICs

how would u connect the IC as shown in the circuit without altering the course of the metallic line ?

 

[Terminator Electricity]

hey, watever it is , i really need an answer to this]

this is my scr : SSC TY 6010 78029

plz could u tell me how to read it and how to connect it in the circuit ?

 

[IanP]

TY6010 is similar to TYN610 ..
Its data sheet can be dowloaded at:
http://www.datasheetcatalog.com/datasheets_pdf/T/Y/N/6/TYN610.shtml

Regards,
IanP

 

[Terminator Electricity]

hey,

A ,being the ground, shoulnt be connected to the ground in our circuit ?