DIY Video Housing a success...

[Bobby_M]

cyclical,
I wouldn't use polycarb because it scratches too easily. It's actually "stronger" in that it doesn't shatter, but to do that it has to be more soft. If I were building a 6" diameter window, I'd probably go with 3/4 or 1" acrylic since it's a larger span. Freckleface.com is the cheapest source I know of for both polycarb and acrylic.

My next step is figuring out how to machine some flats on the housing where the latches screw on. It would be nice to have them sit flat.

Bobby

Bobby

 

[cyclical]

cyclical,
I wouldn't use polycarb because it scratches too easily. It's actually "stronger" in that it doesn't shatter, but to do that it has to be more soft. If I were building a 6" diameter window, I'd probably go with 3/4 or 1" acrylic since it's a larger span. Freckleface.com is the cheapest source I know of for both polycarb and acrylic.

My next step is figuring out how to machine some flats on the housing where the latches screw on. It would be nice to have them sit flat.

Bobby

Bobby

Freckleface.com is where I was going to purchase it from... the cheapest I have found anywhere. Thanks for the tip on scratching easily, I guess I will prob. go with some 3/4" stuff then acrylic.

Im going to try to cut it with a jigsaw and some very good patience. Let me know when you pressure test your set up, many have said sched 40 has worked to around 100+ feet with no problems. This would decrease my overall expense considerably.

 

[Bobby_M]

A quick update for those thinking about building one of these. Tapping threads into PVC doesn't work too well. It taps ok, but the screws don't hold very well. I decided to use nurled threaded inserts instead. These act a bit like a drywall anchor. You drill a 3/16" hole in your PVC, insert the metal insert, and then screw in the screw. So far, it seems like a much more solid attachment which is important since your sping latches have to apply a pretty great force to seat the Oring. I'll have some pics available soon. My next step is to figure out how to apply the PVC cement and get the pieces together without making a mess all over my acrylic ports. I was thinking of try to be conservative and then shoot in some extra cement with a hypo neddle afterwards. Any hints?

Bobby

 

[Padipro]

I don't know why you're having trouble with the screws there Bobby but I've never had a bit of trouble with them after building 2 video housings and at least 3 light canisters. Granted PVC is soft so if you try to really tighten the screws down you can strip out the threads but then again you don't need to tighten them down that much. Here's what I do. First, predrill the screw holes, making sure that the hole is smaller then the screw threads so there is enough material for the screw to grab on to. Then install all of the screws in the predrilled holes without the latch, (Installing the screw in the hole will cause some of the material around the hole to rise up so you'll need to use a counter sink to remove it inorder for the latch to sit flush). Then, when you're ready to permantially install the latchs put a dab of epoxy glue on the screw threads and install the screws. You'll be lucky to get the screw back out without breaking off the head once the epoxy dries.

I've used this method on every housing and canister I've built and have never had a single problem with screws, unless you count the head I twisted off one screw trying to get it out after the epoxy had dried.

 

[Bobby_M]

Scott,
Thanks for the tip. I was actually drilling and tapping the threads with a tap and not formng the threads with the screw itself. I suppose that may have made a difference. The dab of epoxy is an obvious solution that I overlooked thinking I'd have some need to unscrew perhaps to swap the latches to a later generation design. I've already mounted the threaded metal inserts for the latch body, but I'll probably use your method for the catches. Another interesting tidbit.. 1/4" screws are too short and 3/8" are a bit too long. Obiously you don't want them to penetrate the inner pipe wall, but the 3/8" only requires a 1/16" deep hole in that inner wall so I think it would be OK to remove that material as long as the drill doesn't get away from me.

Bobby

 

[Padipro]

You're right about the screw length, I solved this problem by installing a small piece of PVC inside the canister to add a little more thickness to the wall. Since the battery pack is semi square the added piece of PVC didn't get in the way of the battery and actually helped hold it in place so it didn't flop around inside the canister. I was also using wood screws to mount the latches instead of machine screws. The wood screws have a more agressive thread then the machine screws and hold better. When I upgraded the canister and needed to remove the latches from the old one it was a little tough to remove the screws due to the epoxy but all came out except for one and the head just twisted off that screw and allowed me to remove the latch. I wasn't planning on using the old canister again so it wasn't a real big deal to me.

You can just see the piece I added inside the canister if you look below the catch on the lid. It's a square piece of PVC tubing about 1.5 X 1.5 inches sanded flat on the inside face. Since it's made from the same sized tubing I used to make the canister the curve fits the inside of the canister and after I sanded the one side flat it allows clearance for the battery pack. I just slopped a bunch of glue on it and clamped it in place inside the canister where the screws were going to come through the wall. Of course I measure the lenght of the screws to make sure they wouldn't go all the way through and then mounted the latches as I discribed above.

 

[Bobby_M]

I really have no idea why I chose machine screws over sheet metal/wood screws. Here's a shot of those inserts I was talking about:

You can also see how I machined a bit of a "flat" into the PVC coupling so the latch wouldn't rock. All my screw locations are in doubled up PVC areas anyway. On the cap side, I used a short ring of 4" PVC inside as a backing. On the body side, it is screwing in to an ouside ring (pvc coupling cutoff) glued on to the body.

Here's a shot of my clamping method when I glued the acrylic disc inside the 4" PVC coupling. Progresso soup can and 10lb weight. I used IPS Weldon #16 which is a thickened acrylic solvent adhesive. The IPS website suggested this is one of the appropriate adhesives for acrylic to PVC bonding. I hope they are right.

I need to get this thing done for a test run before my June Ft Lauderdale trip ;-)

Bob

 

[MATTKINZ]

Mattkinz,

That looks great what did you use to glue the plexi to the side of the pvc?

Both Plexiglass and PVC will weld both with PVC cement and with superglue. I began with PVC cement and used a medical syringe with small needle to add superglue to cappilary fill any gaps. Worked like a charm.

I just finished housing with paint and built a simple leak detection system using 2 plates of Stainless steel separated by toilet tissue as a switch. see pics.
Any kind of metal works, even aluminum foil on popsicle sticks. Tape a wire from the batteries to one plate and the wire to the bulb to the other. Insulated with tissue , you can tape the plates together and 1 drop of seawater will light your LED bulb.

 

[hilk]

Both Plexiglass and PVC will weld both with PVC cement and with superglue. I began with PVC cement and used a medical syringe with small needle to add superglue to cappilary fill any gaps. Worked like a charm.

I just finished housing with paint and built a simple leak detection system using 2 plates of Stainless steel separated by toilet tissue as a switch. see pics.
Any kind of metal works, even aluminum foil on popsicle sticks. Tape a wire from the batteries to one plate and the wire to the bulb to the other. Insulated with tissue , you can tape the plates together and 1 drop of seawater will light your LED bulb.

how you construct the O ring groove and what type of o ring used ????

 

[426Scuba]

Both Plexiglass and PVC will weld both with PVC cement and with superglue. I began with PVC cement and used a medical syringe with small needle to add superglue to cappilary fill any gaps. Worked like a charm.

I just finished housing with paint and built a simple leak detection system using 2 plates of Stainless steel separated by toilet tissue as a switch. see pics.
Any kind of metal works, even aluminum foil on popsicle sticks. Tape a wire from the batteries to one plate and the wire to the bulb to the other. Insulated with tissue , you can tape the plates together and 1 drop of seawater will light your LED bulb.

That thing looks awesome! I wish I had time to work on my housing the HONEY DO list just keeps getting bigger. I have a new bandsaw that has been unopen for 2 months. I also need to find some 6" pvc (all I can find is a supplier that will sell me 20')