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View Full Version : Out-gassing in sh*t pipe---should I be concerned?



John Kasaian
29-Oct-2004, 12:33
Since 7" wide roll film has gon out to lunch and never returned, I have the added chore of cutting down 9-1/2" wide roll film to 7" in order to feed my Keystone F-8 aerial camera. I've been collecting 7" spools and now have a small supply of cut down film to spool up. The problem is once I load the spools I need a dark container to put them in until needed. The 9-1/2" canisters are so much bigger I'm afraid the spool will get damaged by rattling around inside them. Perhaps the worst case scenario would be that the roll of film would become untaped and unspool itself inside the container and somehow damage the emulsion. To solve the problem I bought some ABS black sewer pipe and end fittings---one side capped and the other a threaded clean out plug---and after cutting to fit the length of the spools I used the recommended cement to glue two sh*t pipe "cannisters" together.

They look kind of like home made bombs and will certainly be instrumental in securing some notariety for yours truly at the airport, but thats another issue.

My concern is that the cement recommended stinks! I've left the two home made casings out in the yard to "air-out" for the past three days and finally there the stink is gone. My concern is that the plastic might possibly be outgassing and if so, that it might damage the film.

The cement contains methyl ethyl keytone 78-93-3 and ABS resin.

Should I be concerned? Any thoughts?

Thanks!

pico
29-Oct-2004, 12:46
You would have had no worries if you had rolled a paper around the finished roll of film and padded the remainder with a little newspaper. Be a bit concerned about the plastic pipe outgassing - not a worry if you use it soon enough. I think you were better off with the original milspec tubes.

Donald Qualls
29-Oct-2004, 14:26
I use tubes similar to your storage units to develop my 9x12 cm and Minolta 16 film -- ABS drain pipe cemented with ABS cement, a solvent weld cement most likely the same composition you used, and "transition cement" which bonds ABS to PVC (and probably is of similar composition with the addition of some PVC).

I haven't seen any effect on film in developing, though I did leave the glued parts open for several days and wash with dishwashing detergent ("Dawn" brand, for hand washing) before using the pipes for developing tanks.

FWIW, if outgassing is a major concern, you might experiment with simply friction fitting the caps on the pipe -- if seated solidly, the tubes I have won't pull straight off, wet or dry; I have to twist them to break the static friction before they'll come off the tube (though I haven't flown with them; pressure changes on an airliner flight could possibly pop a cap off if it's airtight but retained only by friction). Generally, however, I wouldn't expect problems after you can no longer smell the MEK; that solvent has a very distinct odor, and closing the tube for 24 hours will tell you if it's still outgassing enough to be a problem.

As you say, though, your pipe tubes are almost certain to attract unwanted attention in airports; I'd recommend foil wrapping the film rolls inside the tubes so you can open at least one in daylight and show that they're innocuous; otherwise, inspectors are almost certain to demand either x-ray or opening the tubes, fogging the film either way.

bob carnie
29-Oct-2004, 15:48
John
I'm curious as to how you are cutting the roll of film down, My needs are to cut down large rolls of paper into smaller rolls and am struggling with a way of doing this.
your help would be appreciated

Neil_4793
29-Oct-2004, 17:31
John why not make a 1, 1/2" spacer for your 9" rig. Bob you may want to try cutting rolls of paper with a miter saw and 40+ tooth carbide blade,works great on any thing with a ridgid core.

John Kasaian
29-Oct-2004, 21:32
Thanks everyone for your input.

Pico---I could use the original milspec cans and use some kind of padding inside but I don't have any extras at present. I wish I could find some of the original 7" cans though.

Donald---Thanks for the suggestions.

Bob---I've been playing with making jigs for cutting down film but I haven't found a really workable way to slit long lengths of the stuff yet. You can make a jig using a length of laminate particle board from Home Depot and a piece of aluminium angle "iron" that will hold down and overlap the film edge the distance to be trimmed, then simply run a razor blade against the metal edge. Any piece longer than a couple of feet in length is a real handful for me(and, of course I'm quite lazy!)

The last batch of film I bought from Ed "Mr Foto" on eBay, was slit by a lab that was doing custom work for Ed but unfortunately soon after the service became available the slitting machine apparently gave up the ghost.

Photo Warehouse offers custom cut film but its film base material is too thick to work in the F8.

Neil---The problem I have with the 9" camera is that its so heavy that I've already sprained my back :-( and might have contributed to having to have a hernia repaired:-0 Perhaps if Ed McMahan sends me that publishers clearing house deal so I can rent a roomy B-25 to shoot from it will be worth my while, but a cramped Cessna or Super Cub requires too much gymnastics for this old guy, so I've downsized to a 7" wide spiffy Keystone F8 and cut the wieght and bulk (and chemicals come to think of it) in half:-)

Bill_1856
30-Oct-2004, 14:33
"What can go wrong, will go wrong," Murphy.

Chad Jarvis
30-Oct-2004, 18:20
On a side note...is a Keystone F-8 related to a Fairchild in anyway?

John Kasaian
30-Oct-2004, 21:15
Chad,

Heck if I know. All the U.S. aerial cameras of that era seem to have a strong family resemblance though so it could be.

----Cheers!

Conrad Hoffman
31-Oct-2004, 07:16
I've built a variety of small vacuum chambers and other stuff from PVC pipe. The outgassing is certainly bad for the first couple weeks, but eventually the smell goes away and they settle down. Just wait a while and you should be fine. I don't think the solvents have much effect on film once the joints are cured.

jantman
31-Oct-2004, 16:51
It doesn't need to be an air-tight seal. You could always use epoxy to secure the end caps, or some other type of more neutral sealant, or even duct-tape them on.