Axiom Home Page Forums General Discussion The Water Cooler Looking for black cord

I am working on my projection screen masking system (to cover up the top and bottom "gray" bars on the screen).

Anyway, I found a really simple system that uses 2 pulleys (one on the left, and one on the right) that allows for the top and bottom "masks" to move together, so if I lower the top mask, it pulls on the cord, over the pulley, and pulls up the bottom mask as well.

Anyway, I picked up the smallest pulleys I could find, but they still aren't really small. Now I need some cord, rope, string, whatever, in black to connect everything up. I am having a hard time finding anything. I would think that it would need to be 3mm - 5mm in width, and I need about 20 feet of it to make sure that I have enough.

I've seen various types of materials used, but does anyone know what would be strong yet fall within the 3mm-5mm width, and of course be black, and fairly cheap? I know it is a crazy request, but Dr. Google is helping me find stuff, but I am not sure what materials would work best.

You could try black parachute cord for about $4 for 50 feet.

http://www.vtarmynavy.com/parachute_cord.htm

Not sure if the diameter would work.

Nick you may want to try using braided fishing line, something like PowerPro ... it is extremely thin, flexible, comes in various colors and is readily available at just about any store that sells fishing supplies.
PowerPro

If you go to a marine supply store, you should find all kinds of choices.

Of course, I just realized you are in Iowa and there are probably not many Marine Supply stores around in a landlocked state. Online maybe?

I'm sure you will find something but if not, just let me know what you want and how long and I can pick it up for you and ship it to you. My buddy runs a marine shop so pricing should be decent.

The parachute cord is pretty good, but it will run me about $15 for something that might not work due to its size and the web site claims that it may be "flat" which might "jam" in the pulley.

The braided fishing linemay work, but I am concerned that the color would come off as noted in the "cons" section of the bottom of the page. It would run about $15-$20 once factoring in shipping.

These do give me a few other ideas to look in to. Murph, I'll let you know if I need something. Do you have any links to the type of stuff you are talking about?

Nick,

Find some white cotton rope in the exact size you need.

Then dye it black with RIT dye...

Just my .02...

WhatFurrer

I was thinking of some 3 strand Marlow line or some 3 strand polyester rope. It often comes as small as 4mm. Any 3 strand line actually. You could even just go get some at a hardware store. Although, I might avoid nylon unless you like splinters. Color might be the only issue at a hardware store.

I say three strand because then you can do a 3 strand eye splice so you don't have a big knot running through the pulleys all the time.

I had a second thought about the marine supply stores though. They tend to sell in bulk by the reel so it would be costly and you would end up with 300' plus. Maybe you could go into the screen retractor business???

I'll fire my buddy off an email to see if he has 20' scraps of 4 to 6 mm black line laying around, just in case.

Slightly off-topic here, but do you mean you found a plan online for building a screen masking system?

Nick

If there is a web site associated with the pulley system you found could you post the link. I don’t have a projector yet but a DIY masking system is one less reason not get one.


@ Amie

Screen masks are usually black material that covers the top, bottom and or sides of your HT screen so that only the reflective area that is exactly the same size as the picture you are projecting is uncovered. Without the mask the unused part of the screen will likely show up as gray bars above, below or to the sides of the picture rather than a nice sharp black boarder as I the pictures in the link below.

http://www.projectorcentral.com/235_home_theater.htm

Sort of. It took a lot of searching, and it could be tweaked to be better, but for a start, it is pretty simple...

Now for my "master" MSPaint skills...
Basically, the screen is gray, the "masks" are black (I made them a little larger for the diagram to differentiate them more, the pulleys are blue at the top, and the "string" or cord is also blue.

The top and bottom should be fairly evenly weighed out. When the top moved down, it makes the bottom move up and vice versa.