Looking for a pic of a Jib component.
 

Does anyone have a closeup pic of the tension knob on a jib? I'm building my second jib/crane and this is the only piece I haven't figured out. It's the knob the locks the arm in place. Like on the Jimmy Jib...

Here's a 3d pic of the design I'm building.

http://www.sunrushmusic.com/micro35/armassembly.jpg

Thanks for any help!!

hi james,
not sure whether this would help. http://cgi.ebay.com/ws/eBayISAPI.dll...tem=3849203643
there is one pic of mid section of the jib close up.

ed

Skycrane
 

Hello James,

Bob Jones here from Skycrane mini DV camera jibs.

If you'll go to my website www.skycrane.com, you'll find some close up shots that my help in your endevour to build a jib.

HAPPY HOILDAYS...

Bob Jones

Hi James. I have a couple of questions. First, how are you going to keep you camera level? Robert Jones does it using a cable/pulley system that requires the operator to use to keep the camera level, or not. A better way, IMHO, is the classic method developed by Chapman cranes in use by the motion picture industry forever. Their nifty solution was to add a second beam similar in length to the main arm, and by connecting this second beam to the main arm, they could create a platform that remains level at all times. It's easier explained by a picture than my clumsy words. Go to www.chapman-leonard.com and click on the products page. Then, take a look at any of their big cranes, such as the Nike/Electra. This will give you a good idea what I am talking about. Then, check out any of their jibs, such as the Lenny Arm, which are designed to be used with a hot head, and you will see that they use this same double arm design.

Of course, using this double arm design means you need a hot head type device to control the camera movement on the camera platform. So, you might want to use the cable system, like Robert. Just so long as you have this in mind in your design.

The brake is usually designed into the joint where the arm connects to the fulcrum (or post), and is almost always a very simple friction design. Since the arm should always be balanced with the camera mounted on the jib, you don't need a very sophisticated braking system.

Good luck
Wayne Orr, SOC

Thanks everyone for your responses.

The ebay pics help! And I've ran across the skycam site many times! Clean looking product!

My first jib used the parallel bar. It is an 8ft that can reach up to 9 ft. It's a great indoor jib, and from the camera view, that 9 ft looks very high. After seeing the larger jibs on several sets, I decided to build one. And it was perfect for testing out my new machine shop tools I've purchased. I'm wanting to build mini35 type devices for the general public so building the jib first would help me perfect my tool skills. Here's a shot of my current jib. I've recently changed up the design to use a different post (centered) that I can mount on a tripod.

http://www.sunrushmusic.com/micro35/jameyjib2.jpg

The new design is going a bit further. I'll be using a cable to keep things level similar to the jimmy jib design. I'll use tension cables as well. I'm also building the a motorized pan/tilt mechanism. I'm actually building the pan/tilt arm first since it's the most difficult. Everything is ready to go, I've just got to get it all welded up. I turned the bearing sleeves etc on my new mini-lathe. It's been alot of fun.... Especially building it in solidworks first to make sure everything fits together and then having 'plans' to build from!

Back to the original subject. I'm still kind of in the dark in how the break works. Is there a nut or a rubber stop on the end of the knob/bolt? And is the post threaded? So turning it counter-clockwise engage the break?

Thanks guys!!

nice design, i have a skycrane jr. and i love it, i just built a pretty solid dolly out of plate steel.

the only thing i want to change is to find a more solid way of mounting it to the dolly without having all three legs of the tripod taking up space.

how did/are you going to build the column to hold up the crane?

i wish the skycrane people who make dollys, if they were half as good as the skycrane jr. i wouldn't have to be building my own!

the ultimate for me would be a hydraulic column that i could raise/lower that wasn't $5,000

matthew

I'll be using a square or round post with cables and turnbuckles. This should allow me to set it up and break it down fast.

Thanks for the comments!