Adding vents to Smiley bags
JS
Smiley bags (AS-W27). I can't get all the air out of these bags with
the usual foot pump. The factory bags were vented and held more water
but look fragile and already leak.
Alternatively, parts and procedures for DIY.
Thanks,
Jim
T8
Um, maybe you need to fill your non-vented bags like everyone else
does? Wing tip down, detach hose from valve, use funnel and extension
hose. Fill, burp, repeat...
Inelegant, but works.
Tip: use McMaster Carr latex hose in preference to tygon. Much
softer, easier to work with, especially when cold.
I plugged the vents on my vented Smileys.
-Evan Ludeman / T8
JS
and fill both wings simultaneously, vacuuming first especially if the
bags are not vented. This worked for the LS-4 (both vented and
unvented bags), LS-6 (unvented), AS-W20 (vented), another AS-W27
(vented), but of course not the Nimbus 3. Never flew with water in the
AS-W17 or AS-H26.
The funnel sounds a bit 70s. I don't like to support one wing full
of water on a wing stand either, as I've seen people squash the foam
core that way.
This set of bags doesn't vacuum as well as others. Perhaps they just
need removing/replacing using the correct facial expressions and
abusive phrases? Would it help to drill more holes in the inner pipes?
The factory bags are vented and fill easily, but look like water bed
material. After having a similar bag break in flight - filling the
cockpit with water - there's a preference to use heavy duty bags. At
least the factory bags are not shower curtains as removed from the 4
and the 17!
Somebody may know how to vent the Smileys...
Jim
T8
> The funnel sounds a bit 70s. I don't like to support one wing full
> of water on a wing stand either, as I've seen people squash the foam
> core that way.
That's avoided by putting the stand at the tip only. It helps to have
a stand that can go a foot or two higher than normal. As second wing
fills, it will drop to the ground.
Good luck on your project.
-T8
bumper
>
> -Evan Ludeman / T8
Evan,
What about using silicone rubber tubing from McMaster-Carr . . .
unlike "latex", excellent weather and ozone resistance, better
temperature range too. In my experiece, which doesn't include smiley
bag applications, latex doesn't last all that long when exposed to the
elements.
bumper
zz (lower case, Paul:c)
Minden
QV and MKIV
T8
(sorry about the hijack...) The tubing I am using is #5234K61 1 x
1-1/4, black. Shore 35A (very soft, stretchy, doesn't take a set).
It's more durable than you think, and I think many people would
mistake it for silicone. Two seasons, doesn't look any different than
new. Nothing wrong with silicone in general, but I don't see anything
in the catalog that I'd use in preference to the latex.
-Evan Ludeman / T8
Andy
You don't want to vent the bags. What you need is an effective way to
fully evacuate them before filling.
On my ASW-19b I modified the bag root end fittings to include a "T" to
a small bore tube. The dump fittings were connected to the delivery
stand pipe by means of a "Y" fitting.
I purged all air from the fill hoses then attached them to the the
fill/dump ports with the dump valves closed. I then sucked the air
out of the small bore tubes with a harbor freight hand operated
sunction/siphon pump. It took 10-20 seconds for each bag. After the
bags were evauated I pinched off the small bore tubes and opened the
glider dump valves.
The neat part about my fill system was the recirculating stand pipe.
I had the only completely unattended fill system that I have ever
seen. I'd suck the bags, start the fill, and then go the pilot's
meeting. When I came back at the end of the meeting the bags were
full and all I had to do was close the dump valves and disconnect the
fill hoses. No burping, no wing down filling, no water in the
cockpit. no trapped air. Just walk away and forget it.
With this system I could even fill the glider while towing it to the
contest grid and did several times.
Andy
JS
flight things like washing the glider or uploading a task are much
easier with a standpipe fill.
I'd like to see your "recirculating" standpipe Andy, could you send
an image to staniforthjim?yahoo?com removing the questionable bits and
replacing with the usual?
The 27 bags are in two sections to prevent sloshing. Inner and outer
sections are connected by an internal pipe. Wondering if the bag gets
sucked down onto the pipe and an area of the bag with no holes in the
pipe traps the air. That's an easy fix! Perhaps I'll pull one out
today and have a look.
The factory bag vent tubes are left outside the cockpit for filling
and then connected to the T fitting in the top of the fuselage.
Jim
Andy
> I'd like to see your "recirculating" standpipe Andy, could you send
> an image to staniforthjim?yahoo?com removing the questionable bits and
> replacing with the usual?
I'll try to remember to send it this evening. If you don't receive it
drop me an email using the "reply to author". My profle email is
valid.
The only picture I have may not show all the details and the system is
long gone.
The basic idea was was as follows. I had a 50 gallon tank in the bed
of my Malibu station wagon. A marine bilge pump fed the water to the
base of a 2 (?) inch pvc stand pipe that located on the hinge line of
the tail gate. The base of the stand pipe had 2 ports - the inlet,
and the outlet to the glider fill hose. The top of the pipe located
on the tailgate glass latch pin. About 3 inches from the top of the
standpipe was a T fitting and a pipe fed from that T back to the top
of the ballast tank.
The recirculating stand pipe will only work with a tank system. For
use off a faucet I had intended to design a stand pipe with a header
tank and float valve but never needed it and never built it.
Andy