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Labtecpower
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Sat Jan 15, 2011 10:10 am

You can ask questions here, not worth having their own topic.

Do not answer on a question already answered, unless you have very relevant or imporant information.
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Labtecpower
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Sat Jan 15, 2011 10:15 am

I will kick off. doesn't count as a double post, does it?

I want to make a 6 mm musket, with the barrel having an OD of 8 mm.
It will be a barrel sealing tee-piston valve.
The valve seat will be a 12 mm copper pipe, (10mm ID)
The piston will be a small aluminium tube (10,00 mm OD).
I'm going to pilot it by some sort of hammer actuated presta valve, wich will also be the filling valve.
If everything turns out the way I want, the pilot area will be <5 CC.

Will this piston valve actuate?
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jrrdw
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Sat Jan 15, 2011 3:12 pm

Try again.......

Edit:
Will this piston valve actuate?
It's hard to tell looking at paper (so to speak). Build a rough model and try it.
Look if you must.
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Labtecpower
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Sat Jan 15, 2011 4:58 pm

Cleaned up a bit I see :wink:

Well, the whole point of asking some experienced gun builders, was to avoid having to build it, without knowing if I would get it to work.
(as I have quite limited refunds)

JSR has a lot of experience with small caliber piston valves. maybe he could help.

If needed, I could do some high precision measuring of the piston, and the piston seat. (accuracy 0,01 mm)
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jrrdw
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Sat Jan 15, 2011 5:42 pm

The valve seat will be a 12 mm copper pipe, (10mm ID)
The piston will be a small aluminium tube (10,00 mm OD).
I just cought this at second look. Wont the piston have to be smaller then 10mm?
Look if you must.
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Vincenzo
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Sat Jan 15, 2011 7:34 pm

jrrdw wrote:I just cought this at second look. Wont the piston have to be smaller then 10mm?
Stick to moderating :lol: jk :D
It would have to be more than 10mm, that way it's bigger than the valve seat and the chamber pressure can push it open.
more_eggs wrote:My teachers hated this one:
Teacher: "Matt, take your iPod out in class"
Me: "beg your pardon sir? I can't hear you, I'm listening to my iPod"
:P
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ilovefire
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Sat Jan 15, 2011 8:06 pm

could you at least draw what you mean?
why make it if it dosent shoot?
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Vincenzo
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Sat Jan 15, 2011 8:10 pm

Let's start with you drawing what you mean...
more_eggs wrote:My teachers hated this one:
Teacher: "Matt, take your iPod out in class"
Me: "beg your pardon sir? I can't hear you, I'm listening to my iPod"
:P
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jrrdw
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Sat Jan 15, 2011 8:22 pm

Vincenzo wrote:
jrrdw wrote:I just cought this at second look. Wont the piston have to be smaller then 10mm?
Stick to moderating :lol: jk :D
It would have to be more than 10mm, that way it's bigger than the valve seat and the chamber pressure can push it open.
The seat is 8mm OD, so the piston has to be >10mm or the cylinder has to be <10mm. Other wise the piston wont fit in the cylinder.
Look if you must.
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Vincenzo
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Sat Jan 15, 2011 8:32 pm

Labtecpower wrote:The valve seat will be a 12 mm copper pipe, (10mm ID)
So if the piston is 10mm then it won't work...
more_eggs wrote:My teachers hated this one:
Teacher: "Matt, take your iPod out in class"
Me: "beg your pardon sir? I can't hear you, I'm listening to my iPod"
:P
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saefroch
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Sat Jan 15, 2011 10:00 pm

Neither of the fittings will be exactly 10mm, and even if they don't fit together you can sand down one of them until they fit.
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jackssmirkingrevenge
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Sat Jan 15, 2011 11:51 pm

short answer: yes (assuming tight fit)
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Labtecpower
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Sun Jan 16, 2011 3:27 am

might be a bit confused with the valve seat and stuff... :D

Here is my drawing of the whole piston area..

Image

(click to view full size)

I know the piston won't fit if both the cylinder and the piston are 10 mm.

I can eventually turn a piston out of nylon at my school, and add O-rings.
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jrrdw
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Sun Jan 16, 2011 6:20 am

Labtecpower wrote:I will kick off. doesn't count as a double post, does it?

I want to make a 6 mm musket, with the barrel having an OD of 8 mm.
It will be a barrel sealing tee-piston valve.
The valve seat will be a 12 mm copper pipe, (10mm ID)
The piston will be a small aluminium tube (10,00 mm OD).
I'm going to pilot it by some sort of hammer actuated presta valve, wich will also be the filling valve.
If everything turns out the way I want, the pilot area will be <5 CC.

Will this piston valve actuate?
2 problems here, 1) I have to pay more attennsion to what I'm reading, 2) I your building a "barrel sealing tee-piston valve" with the OD of the barrel being "8mm" then that will be the size of the seat, not 12mm.

You would have to add 2mm more of copper to get the seat to measure 12mm.
Look if you must.
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Labtecpower
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Sun Jan 16, 2011 7:32 am

Well, that was the whole confusion I was talking about :wink:

Okay; valve seat: 8 mm. piston :10 mm.
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