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Fnord
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Wed Aug 05, 2015 7:52 pm

vng21092 wrote:How safe is this?
Depends on the manufacturer's standards.
You might eventually screw up the seals and cause leaks but it's unlikely to explode. The brass valves from Harbor freight are rated for 600 but can fail around 1000psi (personal experience).

You can probably find a more suitable valve on ebay for under $20, look for a 1/4" stainless or hydraulic equivalent.
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vng21092
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Thu Aug 13, 2015 6:41 pm

its alright, i reconfigured my setup to work with the new tank. I'm having it line fed now since I'm going to charge the new tank to about 2500 psi. I just don't feel comfortable using a tank at that pressure as a cheek weld, if the safety burst disk goes off for whatever reason I'll probably go deaf and have a good chunk of high pressure air hit my face, no thanks. Check out the new config, 55 bar, 24 inch x 8mm barrel. I'm considering building my own QEV since these blocks fail pretty often at 55 bar, which isn't surprising at all since they're rated at less than 1/4 of what I'm putting into it . But I like it, looks neat (still gotta paint the barrel though). When it's up and running I'll try to put up a video :D

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Doodmens
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Thu Aug 20, 2015 6:10 pm

Quick question: can I get schrader valves from China or Europe or America with a BSPPT thread on it?
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Sat Aug 29, 2015 7:37 pm

Planning a piston hybrid with about a 2" piston, with my current design I only have the chamber pressure operating on about .6 in3 of the piston's face, I was wondering if this was safe, or if it wasn't enough of area
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vng21092
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Sun Aug 30, 2015 3:49 pm

so... I finally got around to building my own QEV since the block ones kept failing at 800 PSI (yeah I know, what was I thinking), and I'd like to say it worked really well.
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My last reading off the chrono app on my phone gave me 630 fps, just 10 minutes ago I got a reading of 780 fps, I'd say this is due to the fact that I have more air in the chamber now (all 3/8 fittings) and maybe it works better? :roll: Anyways, it worked so well that, my barrel flew out of the PVC it was sleeved in. Yep, no piston failure this time. I took a shot, and my barrel had at least 3 feet of flight
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Does this mean my epoxy didn't cure correctly? What to do?
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Tue Sep 15, 2015 11:37 am

Anyone have any idea how this 5/2 solenoid works? It doesn't seems to work as normal 5/2 solenoids.
I checked the model number, didn't dig up any diagram or manual. It also has a weird exhaust port (no thread, the one with brass particle filter) that is leaking (or it's supposed to do so, can't understand why it exists).
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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 Sep 16, 2015 6:39 am

Some sort of spool I guess?

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hectmarr wrote:You have to make many weapons, because this field is long and short life
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wyz2285
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Wed Sep 16, 2015 8:28 am

Yeah I thought it was a pneumatically piloted spool, but the leak from that hole never keeps the spool pressurized so the pilot does nothing at all. I'm gonna return this back to the store..
Edit: faulty valve, the store gave me a replacement, working perfectly now :D
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
vng21092
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Mon Sep 21, 2015 7:36 pm

Hey guys, if I need pieces of tubing with very specific dimensions, what good websites can you recommend that provide such a service? I need it to be precise as well, I've looked on Amazon and they don't seem to have what I'm looking for.
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Mon Sep 21, 2015 8:12 pm

If it's under .5" id talk to a gunsmith.
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Mon Sep 21, 2015 8:15 pm

Define "precise" as it applies to your requirement...

I buy 4130 tubing from Aircraft Spruce and Specialty...comes in a variety of diameters and wall thicknesses.
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vng21092
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Mon Sep 21, 2015 8:38 pm

I need the outer diameter to be 0.300''. I'm not too concerned about the wall thickness, though I'd like it to be 1mm. As far as length goes I only need about 4'' but I'd settle to purchase a foot just to have some extra.
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Sat Sep 26, 2015 11:49 am

Start with McMaster-Carr., they have an extremely wide selection. Search on tubing, then select the material and you should get a nice table of all the available ID and ODs. If they have it then you might want to look somewhere else to actually buy since McMaster can be a bit pricey.
http://www.mcmaster.com/#standard-metal ... es/=z3w9me
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Fri Dec 25, 2015 4:55 pm

Sorry if this is the wrong place to ask a question but there are no options for posting a question only posting a reply. Can anyone tell what is up with TheUltimateSpudGun website. When I click my bookmark it goes to (This domain has expired.). This is really freaking me out because I have hundreds of dollars and much time invested in building a BL-520 and have a long way to go and USG is the only place I know of to buy the parts. They didn't return emails even when the site was up. I have a phone number from a receipt from Hawaii but will wait until after Christmas to call. Any info in the meantime would be appreciated.
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Sun Dec 27, 2015 9:04 am

I can verify that it doesn't work for me either. They haven't been posting many new products over the past couple of years and I haven't been seeing the advertisements around either, looks like you'll be stuck improvising.

Post up your progress if you'd like some help from here. Odds are there's a part or something you can make rather simply to do what you're trying to do.
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