ISC Spring Lock or CMI Stainless??

[Marquis]

I currently have a CMI Stainless and has sevred me well, though it's starting to show some where and tear. Just wondering if anyone knows how the ISC Aluminum Block with the spring lock on it works?

 

[TreeWhitelock]

block

Yes the spring block is where it's at! You dont have to worry about it unthreading and its lightweight. 2.5 ton is the best.

 

[beowulf343]

I may be wrong, but i thought someone told me a while ago that the wwl on the spring locks is less than it is for the same sized stainless.

 

[Blakesmaster]

I may be wrong, but i thought someone told me a while ago that the wwl on the spring locks is less than it is for the same sized stainless.

I thought it was the opposite so I looked it up in the new Sherrill. There is a light duty ISC block for 3/4" line that will only handle 2.4 ton as opposed to the stainless 3/4's advertised 3 ton, but the heavy duty 3/4" and regular 5/8ths" line ISC blocks will will handle 4.5 and 2.4 ton respectively versus the stainless 3 and 2 ton ratings. So, we were both right depending on which block you buy. I would shy away from purchasing the light duty, smaller ISC block for 3/4 inch line but would highly recommend the other ISC blocks. They're rated for more, are lighter and easier to use than the steel versions.

 

[Marquis]

Alright, thanks a bunch for the info guys. they don't run cheap though, huh? I'll probably try the ISC and then I'll have both and will be able to make my own opinion. Thanks again guys!

 

[beowulf343]

I thought it was the opposite so I looked it up in the new Sherrill. There is a light duty ISC block for 3/4" line that will only handle 2.4 ton as opposed to the stainless 3/4's advertised 3 ton, but the heavy duty 3/4" and regular 5/8ths" line ISC blocks will will handle 4.5 and 2.4 ton respectively versus the stainless 3 and 2 ton ratings. So, we were both right depending on which block you buy. I would shy away from purchasing the light duty, smaller ISC block for 3/4 inch line but would highly recommend the other ISC blocks. They're rated for more, are lighter and easier to use than the steel versions.

You are right, according to sherrill. One of our guys in the office pulled this up for me.

http://www.woodlandint.com/products/arborist___tree_care/blocks_and_lowering_devices/

 

[Blakesmaster]

You are right, according to sherrill. One of our guys in the office pulled this up for me.

http://www.woodlandint.com/products/arborist___tree_care/blocks_and_lowering_devices/

Huh. Wonder if it's a typo or totally different block. I'll have to check mine tomorrow. I assume the WLL is listed right on the block.

 

[kevin bingham]

my CMI block has outlasted and outperformed the ISC block. cheaper and a simpler more straight foward design.

 

[TimberMcPherson]

One thing to keep in mind is that alumium is more prone to getting damaged by being dropped from a height on hard surface like concrete, they can get hairline cracks and you will never know.

I dont know if the blocks are more or less subseptable to that sort of damage but its something I always think about when rigging gear is dropped out of a tree.