Hey guys,

I'm trying to figure out what I can use to extend my crane boom for the contest. I want to use all string. My first thought was a higher pound test fishing line. It is fairly thin and strong. My only concern is that it will stretch.

What r ur thoughts???

I use normaly kite lines.

I use nylon fishing line, it costs 1€/100m :)

be careful that it doesn't cut into the plastic!

i have used nylon strings in some cranes and heavy duty winches, and they have proven to work very well, they are strong, and its hard to stretch them, maybe you can test it, however, i think sariel made a big crane some time ago and he used fishing line, and i dont think it will stretch.

be careful that it doesn't cut into the plastic!

I didn't even think of that!! Thank you!!!!

i have used nylon strings in some cranes and heavy duty winches, and they have proven to work very well, they are strong, and its hard to stretch them, maybe you can test it, however, i think sariel made a big crane some time ago and he used fishing line, and i dont think it will stretch.

i have used nylon strings in some cranes and heavy duty winches, and they have proven to work very well, they are strong, and its hard to stretch them, maybe you can test it, however, i think sariel made a big crane some time ago and he used fishing line, and i dont think it will stretch.

Do u remember the test he used?? I'm at the store now and I'm thinking 50 lb just to be safe

http://www.touwenwinkel.nl/?p=productsMore&iProduct=1848&sName=kevlar-voor-mini-kranen-en-takelwagens

Super strong

this is the video of sariel´s crane

I saw that video, my only concern is that my fishing line is going to be in between the boom sections. I looked at the 50 lb test and it is pretty thin, and i think 50 lb will not stretch under the weight of keeping the boom up. I mean i have used 50 lb test on some nice huge fish... so i think it will work on the crane.

As for the hook cable, im just going to use nylon string. it is thin, but not as thin as the fishing line.

Edited September 14, 20159 yr by aminnich

be careful that it doesn't cut into the plastic!

Is this something to be considered about??

well, if you have a lot of load, that's rubbing over a single point... or moving fast... I wouldn't be surprised if, after a bit of use, you started seeing grooves cut into the ABS plastic

a wider, thicker string/line/cord might be safer - that's why Lego use the thicker, braided string for their heavy-load applications, like cranes, vs the thinner string for basic applications such as car winches, which usually are only wound around a single drum, and have much lower load

ok, thanks for this information, would not have thought of that until my LEGOs were destoryed. THANKS

what i've also used was a string from some good kite, it Was fantastic for the high load of a crossbow string (really hard To load) but it can be fixed trough lego pieces simply ;)

When I asked about fishing lines for my LEGO Clock, the store didn't recommend normal nylom fishing lines as they are not designed to handle static force. They recommended a special fishing line made of Kevlar fibres instead, this works great and is super strong, even for a very small diameter which was needed in my limited space available.

I've just obtained some 1mm diam black braided cord from a craft shop - used for stringing beads - only 5p per metre.

Works great on a hoist drum and self coiling.

I've used a couple of types of super-thin fishing lines. They are very, very strong and they don't stretch even a bit, but they can cut your fingers and they are kind of stiff. I found it much harder to tie a standard knot on a fishing line than or a regular string because of how stiff and slippery they are.

I've used a couple of types of super-thin fishing lines. They are very, very strong and they don't stretch even a bit, but they can cut your fingers and they are kind of stiff. I found it much harder to tie a standard knot on a fishing line than or a regular string because of how stiff and slippery they are.

On the crane that was mentioned above that you used fishing line on was outside of the boom. My concern is that it will be inside and I don't know how much room their will b. I don't want it cutting through the plastic.

EDIT: and their are special knots for fishing line, you can just google them.

Edited September 15, 20159 yr by aminnich

EDIT: and their are special knots for fishing line, you can just google them.

yes, the problem is that you can fit normal string between pins and holes or between spacers and axles but with nylion fishing line it is very difficult because of their cylindric shape and 0.1 mm remains 0.1 mm instead of a sting that can be compressed really a lot ;)

The only way to see if it works is to test it. I'm going to pick up some 50 lb test fishing long and some nylon string. And do some tests weight/stretch wise

I use a line called Dyneema Spectra Extreme Braid Fishing Line for my crane. The thickest one is .55mm and at 100lb very strong. It's also very cheap.

If you have a few runs over pulleys it can get a bit tricky keeping the line on the pulleys if your using the larger ones as you reeve the model

I am planning on using a system of pulleys for the actually hook assembly, but not to extent the boom.

I'm going to feed the fishing line through these:

I'd rather destroy those than an entire beam or something, much cheaper to replace