Yet another APH in construction

Build a homemade water gun or water balloon launcher and tell us about it.
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Datum000
Posts: 9
Joined: Mon Aug 31, 2009 4:30 am

Yet another APH in construction

Post by Datum000 » Sun Sep 06, 2009 3:46 am

Well, I got all the bits for my APH, and assembled everything except the pump.
The pump is the only problem here, as I just bought the wrong size O-rings from a store 5 miles away :mad: .
So I got a .5" wooden dowel and the O-ring size was ID 1/2" OD 5/8". The OD was slightly too large for my 1/2" pvc and would not get in, or if it did, it wouldn't budge...
So what size O-ring is recommended for such pumps?

Sun
Posts: 14
Joined: Sat Sep 05, 2009 2:59 pm

Re: Yet another APH in construction

Post by Sun » Sun Sep 06, 2009 2:12 pm

Did you sand a little bit of the pump so the O-rings could fit without having to stretch out?

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Silence
Posts: 3825
Joined: Sun Apr 09, 2006 9:01 pm

Re: Yet another APH in construction

Post by Silence » Sun Sep 06, 2009 3:05 pm

As Sun said, you can cut a bit of a groove for the O-ring to sit in. Or get a 3/8" to 1/2" O-ring (or something similar; just make sure it's smaller) and stretch it to fit, thinning it in the process.

Datum000
Posts: 9
Joined: Mon Aug 31, 2009 4:30 am

Re: Yet another APH in construction

Post by Datum000 » Sun Sep 06, 2009 9:03 pm

Yes, I sanded it, but they still had to stretch over a section to reach it.
Perhaps I'll get a bundle of 9/16" OD.

Datum000
Posts: 9
Joined: Mon Aug 31, 2009 4:30 am

Re: Yet another APH in construction

Post by Datum000 » Sun Sep 27, 2009 11:18 pm

Well, 4 o-rings later, the pump stubbornly refuses to work.
I've tried to trim em and overlap them and sand them and superglue them etc.
Are there any tips on using these stupid things?
EDIT:
Silence wrote:As Sun said, you can cut a bit of a groove for the O-ring to sit in. Or get a 3/8" to 1/2" O-ring (or something similar; just make sure it's smaller) and stretch it to fit, thinning it in the process.
Actually, that sounds pretty good, I'll try that tomorrow.

Datum000
Posts: 9
Joined: Mon Aug 31, 2009 4:30 am

Re: Yet another APH in construction

Post by Datum000 » Mon Sep 28, 2009 2:55 am

Update: She LIVES!
I finally made a functional pump with sanding and WD-40, with the last o-ring I had!
There are 1 or 2 things to patch up, i.e. a reservior, a pump stop to prevent the uncommon removal of the shaft by accident, and a better nozzle (The one I have is off a bit to the right...)
Pics and vids to come when daylight does.

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