Interesting and useful items.

A place for general potato gun questions and discussions.
User avatar
Gippeto
First Sergeant 3
First Sergeant 3
Venezuela
Posts: 2503
Joined: Sat Jan 19, 2008 10:14 am
Location: Soon to be socialist shit hole.
Has thanked: 2 times
Been thanked: 17 times

Donating Members

Fri Apr 26, 2013 12:14 am

Have been doing a bit of googling this evening, and came across this interesting device...at least I found it interesting. :)



And this too:

http://www.rotaryforum.com/forum/attach ... 1241078276
"It could be that the purpose of your life is to serve as a warning to others" – unknown

Liberalism is a mental disorder, reality is it's cure.
User avatar
jackssmirkingrevenge
Five Star General
Five Star General
Posts: 26179
Joined: Thu Mar 15, 2007 11:28 pm
Has thanked: 543 times
Been thanked: 319 times

Donating Members

Fri Apr 26, 2013 12:22 am

Veeeeery interesting.... so 30 x 150 psi means 4500 psi from your average compressor? I'm guessing it does very low volumes though, and from what I can tell is the equivalent of fitting a pneumatic diaphragm to drive a shock pump.

Not cheap, $55 for a slide valve?! http://bogertaviation.com/index.php?pag ... &Itemid=23

Is that you with the autogyro?
hectmarr wrote:You have to make many weapons, because this field is long and short life
User avatar
Gippeto
First Sergeant 3
First Sergeant 3
Venezuela
Posts: 2503
Joined: Sat Jan 19, 2008 10:14 am
Location: Soon to be socialist shit hole.
Has thanked: 2 times
Been thanked: 17 times

Donating Members

Fri Apr 26, 2013 12:49 am

No, not I. Would only be caught dead in one of those. :lol:

The diaphragm chamber is a service brake chamber from a big truck...it's actually 30 in2 effective area (Type 30)... the long stroke chambers(Type 30LS) have a 3" stroke.

Considering they're VERY common, the cost is also VERY low...have seen them online for ~$20-30
"It could be that the purpose of your life is to serve as a warning to others" – unknown

Liberalism is a mental disorder, reality is it's cure.
User avatar
jackssmirkingrevenge
Five Star General
Five Star General
Posts: 26179
Joined: Thu Mar 15, 2007 11:28 pm
Has thanked: 543 times
Been thanked: 319 times

Donating Members

Fri Apr 26, 2013 1:14 am

Staying with PVC, 150 psi on say a 4" piston is a force of 1885 lbs... hooked up to say a 0.5" head diameter pump, that gives you a maximum pressure potential of OVER 9000 PSI!

Slide valve and QEV to power every stroke...
hectmarr wrote:You have to make many weapons, because this field is long and short life
User avatar
Gippeto
First Sergeant 3
First Sergeant 3
Venezuela
Posts: 2503
Joined: Sat Jan 19, 2008 10:14 am
Location: Soon to be socialist shit hole.
Has thanked: 2 times
Been thanked: 17 times

Donating Members

Fri Apr 26, 2013 11:08 am

Safety note...if using a brake chamber, use a service brake chamber...the "double chamber" brake pots contain the parking brake spring, which requires special tools and knowledge to work with...VERY dangerous....as in "crushed rib cage" kind of dangerous.

Priced out a Type 30LS service brake chamber locally @ $40+tax
"It could be that the purpose of your life is to serve as a warning to others" – unknown

Liberalism is a mental disorder, reality is it's cure.
User avatar
Kilash
Private 4
Private 4
Posts: 70
Joined: Thu Jan 21, 2010 12:20 am

Thu May 09, 2013 3:53 pm

I'm guessing this works through hydraulic leverage?
User avatar
Gippeto
First Sergeant 3
First Sergeant 3
Venezuela
Posts: 2503
Joined: Sat Jan 19, 2008 10:14 am
Location: Soon to be socialist shit hole.
Has thanked: 2 times
Been thanked: 17 times

Donating Members

Thu May 09, 2013 10:02 pm

Not familiar with your terminology, but I suspect the answer is yes.

Pressure(100psi) acting upon surface area (30 in2) to generate force (3000lbs)...that force acting upon a reduced surface area (1 in2 to generate a higher pressure (3000psi).
"It could be that the purpose of your life is to serve as a warning to others" – unknown

Liberalism is a mental disorder, reality is it's cure.
User avatar
jrrdw
Moderator
Moderator
United States of America
Posts: 6569
Joined: Wed Nov 16, 2005 5:11 pm
Location: Maryland
Has thanked: 39 times
Been thanked: 22 times
Contact:

Donating Members

Fri May 10, 2013 3:11 am

5 tools to get 1 job done!
User avatar
Gippeto
First Sergeant 3
First Sergeant 3
Venezuela
Posts: 2503
Joined: Sat Jan 19, 2008 10:14 am
Location: Soon to be socialist shit hole.
Has thanked: 2 times
Been thanked: 17 times

Donating Members

Fri May 10, 2013 8:18 am

:lol:
"It could be that the purpose of your life is to serve as a warning to others" – unknown

Liberalism is a mental disorder, reality is it's cure.
User avatar
jackssmirkingrevenge
Five Star General
Five Star General
Posts: 26179
Joined: Thu Mar 15, 2007 11:28 pm
Has thanked: 543 times
Been thanked: 319 times

Donating Members

Fri May 10, 2013 9:26 am

loving the BB shotgun at 2:37 :D
hectmarr wrote:You have to make many weapons, because this field is long and short life
PVC Arsenal 17
Staff Sergeant 3
Staff Sergeant 3
Posts: 1762
Joined: Mon Mar 27, 2006 4:18 pm
Location: United States

Fri May 10, 2013 11:42 pm

This looks like something that could easily be duplicated using two air cylinders of different bores. The one with the larger bore, of course, drives the one with the smaller bore. In fact, that's quite similar to what they seem to have done with an earlier model:

http://bogertaviation.com/index.php?pag ... &Itemid=23

Although I suspect that here, there is a single shaft with duel pistons, one for each size bore.
User avatar
wyz2285
First Sergeant 2
First Sergeant 2
Austria
Posts: 2385
Joined: Sat Mar 06, 2010 7:50 am
Location: Porto, Portugal
Has thanked: 1 time
Been thanked: 3 times
Contact:

Sat May 11, 2013 9:39 am

Pressure(100psi) acting upon surface area (30 in2) to generate force (3000lbs)...that force acting upon a reduced surface area (1 in2 to generate a higher pressure (3000psi).
Assuming that the input air used to push the strock is then exhausted by the slide valve... for each amount of effective charge, 30 times more air is wasted :?
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
User avatar
Gippeto
First Sergeant 3
First Sergeant 3
Venezuela
Posts: 2503
Joined: Sat Jan 19, 2008 10:14 am
Location: Soon to be socialist shit hole.
Has thanked: 2 times
Been thanked: 17 times

Donating Members

Sat May 11, 2013 2:45 pm

It takes energy to do work.

The operational cost of such a unit is still very low compared to any alternatives I have available. Even a box of doughnuts for the firehall to get a fill is going to cost more than using this.

That I could use it at home in my garage to keep my tanks full on MY schedule is a huge bonus IMO.
"It could be that the purpose of your life is to serve as a warning to others" – unknown

Liberalism is a mental disorder, reality is it's cure.
User avatar
wyz2285
First Sergeant 2
First Sergeant 2
Austria
Posts: 2385
Joined: Sat Mar 06, 2010 7:50 am
Location: Porto, Portugal
Has thanked: 1 time
Been thanked: 3 times
Contact:

Sat May 11, 2013 3:06 pm

I don't have any large size compressor, so use my hill mk3 pump is still easier than pumping a bike pump a couple million times :p
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
User avatar
Gippeto
First Sergeant 3
First Sergeant 3
Venezuela
Posts: 2503
Joined: Sat Jan 19, 2008 10:14 am
Location: Soon to be socialist shit hole.
Has thanked: 2 times
Been thanked: 17 times

Donating Members

Thu May 23, 2013 8:32 pm

:)

Collect some stuff...

Image

Do some work...

Image


A little more...

Image

Image

Bored the brass cylinder liner to final after work...no pic. With a little luck, I'll be testing by next weekend. :)
Last edited by Gippeto on Fri Jun 14, 2013 8:39 pm, edited 1 time in total.
"It could be that the purpose of your life is to serve as a warning to others" – unknown

Liberalism is a mental disorder, reality is it's cure.
Post Reply