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Moonbogg
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Sat Nov 16, 2019 2:52 am

Cthulhu wrote:hahaha, alright. I always feel bad when I do that and my ideas turn into a pipe dream :oops:
Pipe dreams have a tendency to become reality at some point down the line in this hobby. I started thinking about my last project like 6 or 8 years ago or something and just recently did it. Do some sketches and stuff. It's fun. Paint is all that is needed.
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wyz2285
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Sat Nov 23, 2019 3:41 am

Balanced vs unbalanced regulators, whats the difference and why one is better than the other?
CpTn_lAw wrote: :D "yay, me wanna make big multishot pnoob with 1000 psi foot pump compressor using diamond as main material. Do you think wet bread make good sealant? " :D
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jackssmirkingrevenge
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Sat Nov 23, 2019 7:25 am

wyz2285 wrote:Balanced vs unbalanced regulators, whats the difference and why one is better than the other?
Balanced regulator:

Image

Unbalanced regulator:

Image

The difference is the way they close the inlet pressure.

In the case of the balanced regulator, you can see that when the inlet is closed, the inlet pressure exerts no force on the stem.

This means that it is better at dealing with an inlet pressure that is fluctuating.

In the case of the applications we are familiar with like paintball bottles, regulators are typically unbalanced.
hectmarr wrote:You have to make many weapons, because this field is long and short life
Haniball1337
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Mon Dec 16, 2019 1:33 pm

Hi , short questions :D Can I connect this two 4,5 mm barrels in one longer like this? I have short barrel and I want now it little longer. I will just put this two OD 6mm tubes in one 6 ID tube. Will it work? Will it ruin accuracy? Can the power decrease?
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jackssmirkingrevenge
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Mon Dec 16, 2019 9:16 pm

You will get more power, though if they aren't perfectly joined together you might lose accuracy. You could use a 4.5mm ID drill bit or similar rod as a mandrel when you glue them together.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Fri Dec 27, 2019 6:41 am

I find it a bit complicated to electrically insulate the high voltage cables from the sparks. At times it seems that only space can make the spark not jump where she wants. :? What materials do you use to insulate? Is there any special type of cable for this purpose? They tell me from these sides that silicone can be used ... any ideas? :roll:
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Sat Dec 28, 2019 10:59 pm

hectmarr wrote:I find it a bit complicated to electrically insulate the high voltage cables from the sparks. At times it seems that only space can make the spark not jump where she wants. :? What materials do you use to insulate? Is there any special type of cable for this purpose? They tell me from these sides that silicone can be used ... any ideas? :roll:
Have you tried using wire specially made for high voltage? The wiring from television flyback circuits is really heavily insulated and works well.
This weapon serves to silence the noisy speakers of the stupid of the other street! (joke) -Hectmarr
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Sun Dec 29, 2019 5:56 am

They tell me from these sides that silicone can be used


Good multimeter leads are made from silicone and look at some of the voltages they can handle. Only thing is that a good set can get pricey.
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Sun Dec 29, 2019 8:28 am

I will try to get some cable from the multimeter or the fly back for TV.
The other thing that I have to try is a good common cable inside a silicone tube, model airplane fuel hose, which has a couple of millimeters of wall thickness and is very flexible. Thanks for the answers.
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Sun Dec 29, 2019 12:27 pm

Or simply drop into a garage and ask if you can buy a couple of metres of spark plug cable. It's made for the job. I've seen the silicone hose over normal cable thing done in the model engineering world, too, it works best with multi-strand wire. Apparently (also a hint from the model enginerding lot) you can also use "push back wire" which is normally used for rewiring vintage guitars - here for example : https://www.stewmac.com/Pickups_and_Ele ... _feet.html
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Sun Dec 29, 2019 3:44 pm

Good idea. I think the spark plug wire used in cars is the easiest to get around here, I will try that.
This seems to me that it meets the requirements. It does not specify the nominal working voltage, but it is for high voltage and is not too expensive.
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Tue Mar 03, 2020 2:29 am

Okay heres a weird question that will probably be obvious in hindsight. I think it would make sense but lemme ask you guys:

So obviously there is such a thing as too tight of a barrel for a given projectile. Unless you have a pretty massive air chamber, once you start having to hammer down a projectile (in a muzzleloader) i think it's safe to say you'll be giving up velocity to friction right? What if instead of a tightbore barrel like previously described, you had a normal fitted barrel that narrows down right before the seat. Would this allow a slow-opening valve to reap the benefits of a projectile taking longer to begin moving, but also have a lower friction coeffecient going down the barrel?

This should almost act like a burst disk in that with such high friction the projectile would require a certain threshold of pressure to get it moving, such as with combustion cannons, where the projectile essentially is the valve.
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Tue Mar 03, 2020 6:10 am

Xamllew wrote:
Tue Mar 03, 2020 2:29 am
Okay heres a weird question that will probably be obvious in hindsight. I think it would make sense but lemme ask you guys:

So obviously there is such a thing as too tight of a barrel for a given projectile. Unless you have a pretty massive air chamber, once you start having to hammer down a projectile (in a muzzleloader) i think it's safe to say you'll be giving up velocity to friction right? What if instead of a tightbore barrel like previously described, you had a normal fitted barrel that narrows down right before the seat. Would this allow a slow-opening valve to reap the benefits of a projectile taking longer to begin moving, but also have a lower friction coeffecient going down the barrel?

This should almost act like a burst disk in that with such high friction the projectile would require a certain threshold of pressure to get it moving, such as with combustion cannons, where the projectile essentially is the valve.
I think any gasses getting by said projectile starting half way down the barrel to the muzzle will hinder the power by breaking the momentum created by the tight fit in the breach...

I now wonder if gasses getting by said projectile would create a vacuum effect and help pull the projectile along?
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Tue Mar 03, 2020 10:31 am

Xamllew wrote:
Tue Mar 03, 2020 2:29 am
This should almost act like a burst disk in that with such high friction the projectile would require a certain threshold of pressure to get it moving, such as with combustion cannons, where the projectile essentially is the valve.
Pretty much, as long as the projectile is properly airtight. Effectively the same as the "valveless" concept.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Tue Mar 03, 2020 4:33 pm

@JRRDW, could you explain what you mean by air getting around the projectile and slowing it down? What I had in mind was a barrel diameter that narrows by less than a millimeter, going from decently airtight, to requiring a few tamps with a ramrod to fully seat.
jackssmirkingrevenge wrote:
Tue Mar 03, 2020 10:31 am
Xamllew wrote:
Tue Mar 03, 2020 2:29 am
This should almost act like a burst disk in that with such high friction the projectile would require a certain threshold of pressure to get it moving, such as with combustion cannons, where the projectile essentially is the valve.
Pretty much, as long as the projectile is properly airtight. Effectively the same as the "valveless" concept.
I had a similar idea for a valveless, except using a mechanism like a Quick Disconnect air hose fitting to lock the projectile in place.
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