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"In the world of spuds today"

A place to ask general spud cannon related questions.
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Re: "In the world of spuds today"

Unread postAuthor: farcticox1 » Tue May 23, 2017 3:24 pm

Like this, I guess it does dump the chamber, if I disconnect the supply it fires (as it should do) and the chamber is empty :shock:

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Re: "In the world of spuds today"

Unread postAuthor: jackssmirkingrevenge » Wed May 24, 2017 5:43 am

The problem is that you are trying to empty the pilot area while simultaneously continuing to feed from the air supply. Ideally you want a three way valve that opens the pilot area to the atmosphere while simultaneously shutting off the main air supply:

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Re: "In the world of spuds today"

Unread postAuthor: farcticox1 » Wed May 24, 2017 3:24 pm

This is the valve I am using as a trigger, 3/2 with ported exhaust, so the main supply is cut off when the QEV is vented to atmosphere
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Re: "In the world of spuds today"

Unread postAuthor: jackssmirkingrevenge » Wed May 24, 2017 5:51 pm

That's the ticket... perhaps it has poor flow. Alternatively it would be worth checking your QEV piston/diaphragm for damage. If a QEV flutters then either the pilot valve isn't venting vast enough or air is getting past the piston from the chamber into the pilot area.
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Re: "In the world of spuds today"

Unread postAuthor: farcticox1 » Wed May 24, 2017 6:20 pm

I'm using 4mm OD tubing on the pilot lines, I'll try going to 6mm OD :idea: I have a silencer in the trigger as well, may cause a slight back pressure :idea:
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Re: "In the world of spuds today"

Unread postAuthor: jackssmirkingrevenge » Wed May 24, 2017 6:30 pm

I have a silencer in the trigger as well, may cause a slight back pressure


You mean connected to the venting port? If so I'll wager this is causing the issue.
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Re: "In the world of spuds today"

Unread postAuthor: farcticox1 » Sat Jun 03, 2017 3:40 pm

Tinkering with BFG a bit, still experimenting with sights, decided I have to move the stock a bit lower as well to get a better cheek weld. Anywho decided to finally build a decent target to catch all the BB's flying around, back stop is a thick piece of rubber which deflects them down into the bottom.

EDIT have gone back to the original sight, will finally get it to work
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Also good for tin can ally

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Re: "In the world of spuds today"

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Re: "In the world of spuds today"

Unread postAuthor: farcticox1 » Mon Jun 26, 2017 6:18 pm

A bit of vortex workImage


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Re: "In the world of spuds today"

Unread postAuthor: jackssmirkingrevenge » Tue Jun 27, 2017 5:07 am

Oooh... caliber & intended pressure?
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Re: "In the world of spuds today"

Unread postAuthor: farcticox1 » Tue Jun 27, 2017 5:18 pm

It will be for airsoft (6mm) only gonna be at 125psi ish, probably going to need more flow than I can supply at the moment, this is my long term back burner project at the moment, probably finished around 2020 :shock: I'll be happy if something comes out the barrel when I pull the trigger :P
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Re: "In the world of spuds today"

Unread postAuthor: jakethebeast » Wed Jun 28, 2017 2:33 pm

Quick question.

Brushless RC motor with a 40mm 3 blade quadcopter rotor to went a 7.8 Liter combustion chamber? Good or bad idea?
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Re: "In the world of spuds today"

Unread postAuthor: Gippeto » Wed Jun 28, 2017 5:29 pm

Won't claim to know diddly about combustions, but....you're half way to an edf already....

https://hobbyking.com/en_us/hobbykingtm ... rsion.html

Will certainly move some air. 7.8L works out to 100mm x 1m (roughly 39" of 4" pipe)....not really huge.
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Re: "In the world of spuds today"

Unread postAuthor: jakethebeast » Thu Jun 29, 2017 1:24 am

The venting is done via 2" camlock at the end of a chamber and as I want the fan to be serviceable I bet its much better to have an RC motor with 40mm rotor than a 40mm PC case fan.... Also dont feel like spending more than 5 seconds for wenting :lol:
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Re: "In the world of spuds today"

Unread postAuthor: jackssmirkingrevenge » Sun Jul 02, 2017 8:12 am

jakethebeast wrote:Also dont feel like spending more than 5 seconds for wenting :lol:


Unless you're making a semi-auto, this seems like overkill. That being said, you're an overkill sort of guy, even for a Finn :D
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Re: "In the world of spuds today"

Unread postAuthor: qwerty » Sun Jul 02, 2017 5:36 pm

Still here, arrived when I was 12 and now I'm 20. Time flies.

I swear it never leaves you, I still have an odd fascination with valves and pipes and all sorts... I'll build something someday.
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