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A place for general potato gun questions and discussions.
hectmarr
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Fri Aug 03, 2018 2:36 pm

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farcticox1
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Fri Aug 03, 2018 7:19 pm

hectmarr wrote:Does anyone know what this red knob is for?
That's what I used for the trigger :shock:
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Sat Aug 04, 2018 7:33 am

A beautiful trigger and I unknowingly ... :wink:
Last edited by hectmarr on Sat Aug 04, 2018 7:51 pm, edited 1 time in total.
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farcticox1
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Sat Aug 04, 2018 3:45 pm

Makes for an easy trigger :idea:
hectmarr
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Sat Aug 04, 2018 8:04 pm

farcticox1 wrote:Makes for an easy trigger :idea:
I was improvising this little semiautomatic thing to shoot 6mm plastic balls, I work a couple of hours. That's why it was the question. I operated the shot with the solenoid, but now that I know what the orange button is for, I shot from there, as you explain.
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hectmarr
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Thu Aug 23, 2018 10:09 am

What standard should a steel tube with an inner diameter and about 1.5 mm - 2 mm in wall thickness, manufactured for high pressure?
Can it be ASTM 312 SCH 5S?
I mean what kind of steel tube do you use?
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jackssmirkingrevenge
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Mon Aug 27, 2018 4:40 am

Are you trying to calculate the burst pressure?

This is a good calculator to use, of course you need to know the grade of steel used but you can at least make an approximate determination.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Mon Aug 27, 2018 8:59 am

jackssmirkingrevenge wrote:Are you trying to calculate the burst pressure?

This is a good calculator to use, of course you need to know the grade of steel used but you can at least make an approximate determination.
Yes, just that. I have to buy a steel tube to build some more pressure. The calculator is very useful. Thanks Jack :)
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Tue Aug 28, 2018 4:50 pm

I found this table ... It seemed useful to me and that is why I leave it to everyone's consideration. I put colors to those that interest me, only this.
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jackssmirkingrevenge
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Tue Aug 28, 2018 5:54 pm

The obligatory question is what kind of mix numbers will you be burning?
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Tue Aug 28, 2018 7:51 pm

In my case, low level of mixing pressure, how much 10X, although I have projected 8X for the new camera that I will build. It would be about 1100 psi, 80 bar, as pressure peak approximately, surely less, It would be within the working pressure that tolerates a seamless tube sch 5 of 3/4 "and 1.6 mm of wall.The sch 40 tolerates much more, and is easier to get from these sides :roll:
The problem is that the tubes I am using have a thickness of 0.8 mm and have laminated and polished seam ... I feel uncomfortable when passing 6X, and it would be a serious flaw with the weapon so close to my face. It's not worth risking.
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wyz2285
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Tue Nov 27, 2018 6:00 pm

Anybody knows how a gas ram/ spring works? I tried to make a gas ram powered bolt action but no matter what I do it leaks over time, I made sure the surfaces are smooth, free float and right size o-ring (two of them even!) and it just leaks...
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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farcticox1
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Wed Nov 28, 2018 5:26 am

A bit like a gas ram that holds up a car tail gate.
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wyz2285
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Wed Nov 28, 2018 5:30 am

I know, but how does the inside looks like?
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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Wed Nov 28, 2018 9:03 am

farcticox1 wrote:A bit like a gas ram that holds up a car tail gate.
That's more or less what it is, here is the relevant patent.

Personally, I think such devices are of limited relevance to the average spudder because of the need to retain large amounts of stored mechanical energy on a single point, in a manner similar to a crossbow. It can be done, but it's easier and more practical to store that energy as pressurized gas that is released by a valve. If you look at commercial airguns, there is a fairly low upper limit that such configurations can achieve in terms of energy in the 30 ft lbs range, while precharged pneumatics can be an order of magnitude more powerful.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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