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Timer circuit/555 board

Posted: Mon Oct 15, 2007 7:20 pm
by ShowNoMercy
Its kind of early to be posting this since I get my parts on the 18th but I have made a prototype of a bolt actuated paint ball gun similar to an auto cocker and as of now my controller is a Lego RSX :oops: . It controls two relays which in turn operate a solenoid to fire and a solenoid to work the bolt. I am not to educated at the making of a circuit to replace this and I was wondering if anyone can point me in the right direction? It needs to have this loop;
1. trigger pressed
2. main solenoid fired
3. 2 second wait, bolt solenoid operated
4. main solenoid fired
steps 2 3 and 4 will be in a loop as long as the trigger is held

Any ideas?

Posted: Mon Oct 15, 2007 7:29 pm
by iPaintball
Ask Jimmy101, he seem sto know the most about electronics on this forum. Good luck!

Posted: Mon Oct 15, 2007 7:30 pm
by HaiThar
Are you sure you can do that with a Lego thing? :\ Sounds like you want a microcontroller there....

Posted: Mon Oct 15, 2007 7:31 pm
by ShowNoMercy
Have you ever seen the internals of an autococker?

And yea it works fine with the RSX, I can program it and stuff so it has been a lot of help.

Posted: Mon Oct 15, 2007 7:36 pm
by Hubb
ShowNoMercy wrote:Have you ever seen the internals of an autococker?

Posted: Mon Oct 15, 2007 7:37 pm
by ShowNoMercy
How much does that three way valve run?

Posted: Mon Oct 15, 2007 8:11 pm
by pyrogeek
Check eBay, they have some for $1 from Barbs paintball.

Posted: Mon Oct 15, 2007 8:18 pm
by singularity
i would have to agree with the earlier post, your going to need something like a PIC micro controller or ATMega/ATtiny micro controller... which means your going to need a programmer and know how to do some coding. if you do it the ghetto way it should cost $25 or less

Posted: Mon Oct 15, 2007 8:23 pm
by ShowNoMercy
So there is no way I could rig up a timer circuit that would actuate the relays?

Posted: Tue Oct 16, 2007 7:29 am
by dewey-1
--

Posted: Tue Oct 16, 2007 9:13 am
by Tom
I think this will be much more easy to make whit a little bit of creativity :D .
GR.Tom
http://nerfhaven.com/forums/index.php?showtopic=9706

Posted: Tue Oct 16, 2007 11:45 am
by ShowNoMercy
Both the solenoids operate at around 12 volts so the relay or transistor needs to handle that. The timing I will figure out when I get my parts in and hook it all up with the RSX as a processor. I will try and get it working that way and then figure something out using transistors and some timer circuits. I choose relays now because they were cheap and easy to use. No soldering needed and I can detach and reatach leads..

Posted: Tue Oct 16, 2007 6:06 pm
by TurboSuper
I have an interesting idea which may or may not work, if someone could verify it that would be nice:

The output of a 555 timer, provided it has no DC offset, will have a positive stage and a negative stage. I was thinking that if you could connect 2 diodes in parallel with the timer, in opposing directions, you could isolate the positive cycle in one, and the negative in the other.

After that, it would just be a simple matter of connecting one solenoid in series with one diode, and the other solenoid in series with the other (or the appropriate buffer circuit).

Anyone else think this would work?

Posted: Tue Oct 16, 2007 9:33 pm
by ShowNoMercy
Could you explain that in a bit simpler terms? I understand the diodes but the whole 555 chip is confusing me. :cry:

Posted: Wed Oct 17, 2007 4:55 am
by TurboSuper
Okay, well I was reading up on 555 timers, and it turns out they don't have a negative cycle...so mabye of you switched the diodes for a NOT gate?

Oh, and just google '555 timer', and you'll see what I mean.