Here a few shot of some custom tubes that I had made.
These were made from a mag D cell flashlight for prototype purposes.
I use one for survival items and the other for first aid items.
![](http://farm5.static.flickr.com/4083/5199801303_53b07c776b.jpg)
Custom aluminum tube
![](http://farm6.static.flickr.com/5083/5199801249_f72012256d.jpg)
These threads were cut on a manual lathe.
![](http://farm6.static.flickr.com/5165/5200394006_0ed6273fd0.jpg)
Each cap has an o-ring which make the tube water tight
(I have tested to the depth of my bath tub
![cool cool](/images/graemlins/default/cool.gif)
for over ten hours - dry as a bone inside).
I liked these so much I decided to commission a run of some tubes of my own design.
Here are some initial 3D renderings of my design. Material for consideration is 6061 Aluminum.
![](http://farm6.static.flickr.com/5170/5200394150_cd37e95557.jpg)
Tube - view 1
![](http://farm5.static.flickr.com/4083/5200394174_b2d994c066.jpg)
Tube - view 2
The caps will thread down onto the tube and will be sealed with an o-ring.
![](http://farm6.static.flickr.com/5082/5199801397_31bf681597.jpg)
Cap - view 1
![](http://farm6.static.flickr.com/5008/5199801415_55849bb82d.jpg)
Cap - View 2
![](http://farm6.static.flickr.com/5005/5199801441_2363dbfe2e.jpg)
Cap - View 3