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Fasttrack
08-03-2012, 09:01 PM
I'd like to make a cable reel to organize (12) 100 ft long 22 awg, 26 conductor cables. Each cable is terminated with a DB25 connector.

Some details:
Imagine a wooden cart with cabinet doors and a steel chassis with two wheel barrow wheels and a pad/peg. To move it, one picks up one end and maneuvers it into place. Once in place, the pad height is adjustable so one can level the cart on uneven ground. The cabinet doors can open to reveal the spool and some additional storage. The reel has an external hand wheel to wind the cables. I'd like to keep each of the 12 cables separated in such a way that I can wind them all at once but be able to unwind one at a time, if I so desired. Finally, I'd like to keep the cart as light as possible. My goal is to have it light enough once loaded that two men can pick it up and put it in the bed of a pickup truck. The load consists of the cable, two boxes that are on the order of 10-15 lbs each and some additional misc cables, notebooks, etc. The final constraint is that I would like to do this as cheaply as possible while maintaining functionality and durability.

The cart dimensions would be approximately 36" height from ground, 42" long and maybe 18" deep.

I thought about using three pieces of 1/2" EMT conduit to make the reel so I could easily "tangle" the ends of the cable in the reel to start winding. I'd like some round discs to keep the cables separate, though. These discs could then have slots cut in them to catch the other end of the cable once it was wound, allowing one to unwind a different cable without disturbing the first. I may need a hanger at one or more places along the conduit in order to have enough rigidity to support the weight of the cables. If I do this design, I will have to come up with an easy method of attaching the discs to the reel.

Regardless of design, I think I will want discs between the cables. The question is then: what material should I use? I was thinking about aluminum but that can get costly. Maybe some 1/8" Masonite would work? What do you guys think? Any creative (i.e. cheap!) resources jump to mind?


(For those of you curious about the application, I'd like to make a "shooting station" for pyrotechnic displays. Wired systems are some of the fastest and most reliable firing systems used in pyrotechnics, but that means you have to contend with a considerably rats nest of cable. This is a pain during tear down, which typically happens around or after midnight (with little to no light) after spending all day in the heat setting up the show. Having a mobile cart to set the firing panel and notes on during the show is super handy. Having a reel in that cart that allows one to connect up the bus lines and crank away would be invaluable. I'm envisioning something that I can roll out of the truck/trailer into the field and have all the pieces I need to setup the firing system and shoot the show from)

kf2qd
08-03-2012, 09:38 PM
I see one small problem - 1200 feet of 26 conductor cable may already fail your weight condition. Seperate reels for the cables would probably work out better, Reels stored side by side need to be rolled in opposite direstions to keep them from all unrolling when you pull on any single cable. Then you have about the same mess as if they were all just thrown in a box. Individual reels can be set in a box and you could easily have a "peg" mounted to the truck/trailer to unspool them.

For winding the cables, a piece of plywood 24 inches long with a curved cutout in each end makes a great way to organize cables and it doesn't unroll when you don't want it to. You just walk with the cable and shake the plywood a little and the cable will feed out nicely.

something like this -http://i250.photobucket.com/albums/gg244/kf2qd/CordHolder.jpg

Fasttrack
08-03-2012, 09:56 PM
I see one small problem - 1200 feet of 26 conductor cable may already fail your weight condition.

Nah, all the cable combined weighs 99 lbs. My goal is to keep this at 300 lbs or less, so there is still some room for additional weight!

I forgot about those cable board things. Thanks! I've seen those in the field before, and I may end up doing that ... but I'm hoping for something with a little more "cool" factor without being completely impractical. To be honest, I get along alright just winding the cables on my arm... but it would be much easier/faster if I could wind all the bus lines at one go.

armedandsafe
08-03-2012, 10:41 PM
Design/install a spring-loaded latch on the hub of each reel, so each reel can freely turn to unwind, but the latch (pawl) locks when the shaft is rotated. You would have to place your reels far enough apart that no one reel would touch another when unwinding. All reels turn when winding the shaft lever/handle, but only one turns when pulling on its cable.

We did something similar when recovering irigation line before harvest of ground crops.

Pops

Fasttrack
08-03-2012, 10:45 PM
Design/install a spring-loaded latch on the hub of each reel, so each reel can freely turn to unwind, but the latch (pawl) locks when the shaft is rotated. You would have to place your reels far enough apart that no one reel would touch another when unwinding. All reels turn when winding the shaft lever/handle, but only one turns when pulling on its cable.

We did something similar when recovering irigation line before harvest of ground crops.

Pops


A little more complicated than I had intended, but great idea! Thanks!

mechanicalmagic
08-03-2012, 10:57 PM
I have good luck sandwiching 1" Styro building insulation between 1/8" plywood. Can be used for the box, or the reels. Cheap too.

DJ

Evan
08-04-2012, 01:57 AM
Dollar store stainless steel pie plates/ pizza plates. Two, face to face, between each cable. Some have very low rims, just right and rust free.

Fasttrack
08-04-2012, 11:18 AM
Dollar store stainless steel pie plates/ pizza plates. Two, face to face, between each cable. Some have very low rims, just right and rust free.

Hmm ... I need to find a dollar store! Thanks.

Thanks DJ, for the foam suggestion, too.